the alpha particles experiment

What is the 'Gold Foil Experiment'? The Geiger-Marsden experiments explained

Physicists got their first look at the structure of the atomic nucleus.

J.J. Thomson model of the atom

Gold foil experiments, rutherford model of the atom.

• The real atomic model

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Bibliography.

The Geiger-Marsden experiment, also called the gold foil experiment or the α-particle scattering experiments, refers to a series of early-20th-century experiments that gave physicists their first view of the structure of the atomic nucleus and the physics underlying the everyday world. It was first proposed by Nobel Prize -winning physicist Ernest Rutherford.

As familiar as terms like electron, proton and neutron are to us now, in the early 1900s, scientists had very little concept of the fundamental particles that made up atoms . 

In fact, until 1897, scientists believed that atoms had no internal structure and believed that they were an indivisible unit of matter. Even the label "atom" gives this impression, given that it's derived from the Greek word "atomos," meaning "indivisible." 

But that year, University of Cambridge physicist Joseph John Thomson discovered the electron and disproved the concept of the atom being unsplittable, according to Britannica . Thomson found that metals emitted negatively charged particles when illuminated with high-frequency light. 

His discovery of electrons also suggested that there were more elements to atomic structure. That's because matter is usually electrically neutral; so if atoms contain negatively charged particles, they must also contain a source of equivalent positive charge to balance out the negative charge.

By 1904, Thomson had suggested a "plum pudding model" of the atom in which an atom comprises a number of negatively charged electrons in a sphere of uniform positive charge,  distributed like blueberries in a muffin. 

The model had serious shortcomings, however — primarily the mysterious nature of this positively charged sphere. One scientist who was skeptical of this model of atoms was Rutherford, who won the Nobel Prize in chemistry for his 1899 discovery of a form of radioactive decay via α-particles — two protons and two neutrons bound together and identical to a helium -4 nucleus, even if the researchers of the time didn't know this.

Rutherford's Nobel-winning discovery of α particles formed the basis of the gold foil experiment, which cast doubt on the plum pudding model. His experiment would probe atomic structure with high-velocity α-particles emitted by a radioactive source. He initially handed off his investigation to two of his protégés, Ernest Marsden and Hans Geiger, according to Britannica . 

Rutherford reasoned that if Thomson's plum pudding model was correct, then when an α-particle hit a thin foil of gold, the particle should pass through with only the tiniest of deflections. This is because α-particles are 7,000 times more massive than the electrons that presumably made up the interior of the atom.

Marsden and Geiger conducted the experiments primarily at the Physical Laboratories of the University of Manchester in the U.K. between 1908 and 1913. 

The duo used a radioactive source of α-particles facing a thin sheet of gold or platinum surrounded by fluorescent screens that glowed when struck by the deflected particles, thus allowing the scientists to measure the angle of deflection. 

The research team calculated that if Thomson's model was correct, the maximum deflection should occur when the α-particle grazed an atom it encountered and thus experienced the maximum transverse electrostatic force. Even in this case, the plum pudding model predicted a maximum deflection angle of just 0.06 degrees. 

Of course, an α-particle passing through an extremely thin gold foil would still encounter about 1,000 atoms, and thus its deflections would be essentially random. Even with this random scattering, the maximum angle of refraction if Thomson's model was correct would be just over half a degree. The chance of an α-particle being reflected back was just 1 in 10^1,000 (1 followed by a thousand zeroes). 

Yet, when Geiger and Marsden conducted their eponymous experiment, they found that in about 2% of cases, the α-particle underwent large deflections. Even more shocking, around 1 in 10,000 α-particles were reflected directly back from the gold foil.

Rutherford explained just how extraordinary this result was, likening it to firing a 15-inch (38 centimeters) shell (projectile) at a sheet of tissue paper and having it bounce back at you, according to Britannica  

Extraordinary though they were, the results of the Geiger-Marsden experiments did not immediately cause a sensation in the physics community. Initially, the data were unnoticed or even ignored, according to the book "Quantum Physics: An Introduction" by J. Manners.

The results did have a profound effect on Rutherford, however, who in 1910 set about determining a model of atomic structure that would supersede Thomson's plum pudding model, Manners wrote in his book.

The Rutherford model of the atom, put forward in 1911, proposed a nucleus, where the majority of the particle's mass was concentrated, according to Britannica . Surrounding this tiny central core were electrons, and the distance at which they orbited determined the size of the atom. The model suggested that most of the atom was empty space.

When the α-particle approaches within 10^-13 meters of the compact nucleus of Rutherford's atomic model, it experiences a repulsive force around a million times more powerful than it would experience in the plum pudding model. This explains the large-angle scatterings seen in the Geiger-Marsden experiments.

Later Geiger-Marsden experiments were also instrumental; the 1913 tests helped determine the upper limits of the size of an atomic nucleus. These experiments revealed that the angle of scattering of the α-particle was proportional to the square of the charge of the atomic nucleus, or Z, according to the book "Quantum Physics of Matter," published in 2000 and edited by Alan Durrant.  

In 1920, James Chadwick used a similar experimental setup to determine the Z value for a number of metals. The British physicist went on to discover the neutron in 1932, delineating it as a separate particle from the proton, the American Physical Society said . 

What did the Rutherford model get right and wrong?

Yet the Rutherford model shared a critical problem with the earlier plum pudding model of the atom: The orbiting electrons in both models should be continuously emitting electromagnetic energy, which would cause them to lose energy and eventually spiral into the nucleus. In fact, the electrons in Rutherford's model should have lasted less than 10^-5 seconds. 

Another problem presented by Rutherford's model is that it doesn't account for the sizes of atoms. 

Despite these failings, the Rutherford model derived from the Geiger-Marsden experiments would become the inspiration for Niels Bohr 's atomic model of hydrogen , for which he won a Nobel Prize in Physics .

Bohr united Rutherford's atomic model with the quantum theories of Max Planck to determine that electrons in an atom can only take discrete energy values, thereby explaining why they remain stable around a nucleus unless emitting or absorbing a photon, or light particle.

Thus, the work of Rutherford, Geiger  (who later became famous for his invention of a radiation detector)  and Marsden helped to form the foundations of both quantum mechanics and particle physics. 

Rutherford's idea of firing a beam at a target was adapted to particle accelerators during the 20th century. Perhaps the ultimate example of this type of experiment is the Large Hadron Collider near Geneva, which accelerates beams of particles to near light speed and slams them together. 

• See a modern reconstruction of the Geiger-Marsden gold foil experiment conducted by BackstageScience and explained by particle physicist Bruce Kennedy . 
• Find out more about the Bohr model of the atom which would eventually replace the Rutherford atomic model. 
• Rutherford's protege Hans Gieger would eventually become famous for the invention of a radioactive detector, the Gieger counter. SciShow explains how they work .

Thomson's Atomic Model , Lumens Chemistry for Non-Majors,.

Rutherford Model, Britannica, https://www.britannica.com/science/Rutherford-model

Alpha particle, U.S NRC, https://www.nrc.gov/reading-rm/basic-ref/glossary/alpha-particle.html

Manners. J., et al, 'Quantum Physics: An Introduction,' Open University, 2008. 

Durrant, A., et al, 'Quantum Physics of Matter,' Open University, 2008

Ernest Rutherford, Britannica , https://www.britannica.com/biography/Ernest-Rutherford

Niels Bohr, The Nobel Prize, https://www.nobelprize.org/prizes/physics/1922/bohr/facts/

House. J. E., 'Origins of Quantum Theory,' Fundamentals of Quantum Mechanics (Third Edition) , 2018

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Robert Lea is a science journalist in the U.K. who specializes in science, space, physics, astronomy, astrophysics, cosmology, quantum mechanics and technology. Rob's articles have been published in Physics World, New Scientist, Astronomy Magazine, All About Space and ZME Science. He also writes about science communication for Elsevier and the European Journal of Physics. Rob holds a bachelor of science degree in physics and astronomy from the U.K.’s Open University

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Experimental Evidence for the Structure of the Atom

George sivulka march 23, 2017, submitted as coursework for ph241 , stanford university, winter 2017, introduction.

The Rutherford Gold Foil Experiment offered the first experimental evidence that led to the discovery of the nucleus of the atom as a small, dense, and positively charged atomic core. Also known as the Geiger-Marsden Experiments, the discovery actually involved a series of experiments performed by Hans Geiger and Ernest Marsden under Ernest Rutherford. With Geiger and Marsden's experimental evidence, Rutherford deduced a model of the atom, discovering the atomic nucleus. His "Rutherford Model", outlining a tiny positively charged atomic center surrounded by orbiting electrons, was a pivotal scientific discovery revealing the structure of the atoms that comprise all the matter in the universe.

The experimental evidence behind the discovery involved the scattering of a particle beam after passing through a thin gold foil obstruction. The particles used for the experiment - alpha particles - are positive, dense, and can be emitted by a radioactive source. Ernest Rutherford discovered the alpha particle as a positive radioactive emission in 1899, and deduced its charge and mass properties in 1913 by analyzing the charge it induced in the air around it. [1] As these alpha particles have a significant positive charge, any significant potential interference would have to be caused by a large concentration of electrostatic force somewhere in the structure of the atom. [2]

Previous Model of the Atom

The scattering of an alpha particle beam should have been impossible according to the accepted model of the atom at the time. This model, outlined by Lord Kelvin and expanded upon by J. J. Thompson following his discovery of the electron, held that atoms were comprised of a sphere of positive electric charge dotted by the presence of negatively charged electrons. [3] Describing an atomic model similar to "plum pudding," it was assumed that electrons were distributed throughout this positive charge field, like plums distributed in the dessert. However, this plum pudding model lacked the presence of any significant concentration of electromagnetic force that could tangibly affect any alpha particles passing through atoms. As such, alpha particles should show no signs of scattering when passing through thin matter. [4] (see Fig. 2)

The Geiger Marsden Experiments

Testing this accepted theory, Hans Geiger and Ernest Marsden discovered that atoms indeed scattered alpha particles, a experimental result completely contrary to Thompson's model of the atom. In 1908, the first paper of the series of experiments was published, outlining the apparatus used to determine this scattering and the scattering results at small angles. Geiger constructed a two meter long glass tube, capped off on one end by radium source of alpha particles and on the other end by a phosphorescent screen that emitted light when hit by a particle. (see Fig. 3) Alpha particles traveled down the length of the tube, through a slit in the middle and hit the screen detector, producing scintillations of light that marked their point of incidence. Geiger noted that "in a good vacuum, hardly and scintillations were observed outside of the geometric image of the slit, "while when the slit was covered by gold leaf, the area of the observed scintillations was much broader and "the difference in distribution could be noted with the naked eye." [5]

On Rutherford's request, Geiger and Marsden continued to test for scattering at larger angles and under different experimental parameters, collecting the data that enabled Rutherford to further his own conclusions about the nature of the nucleus. By 1909, Geiger and Marsden showed the reflection of alpha particles at angles greater than 90 degrees by angling the alpha particle source towards a foil sheet reflector that then would theoretically reflect incident particles at the detection screen. Separating the particle source and the detector screen by a lead barrier to reduce stray emission, they noted that 1 in every 8000 alpha particles indeed reflected at the obtuse angles required by the reflection of metal sheet and onto the screen on the other side. [6] Moreover, in 1910, Geiger improved the design of his first vacuum tube experiment, making it easier to measure deflection distance, vary foil types and thicknesses, and adjust the alpha particle stream' velocity with mica and aluminum obstructions. Here he discovered that both thicker foil and foils made of elements of increased atomic weight resulted in an increased most probable scattering angle. Additionally, he confirmed that the probability for an angle of reflection greater than 90 degrees was "vanishingly small" and noted that increased particle velocity decreased the most probably scattering angle. [7]

Rutherford's Atom

Backed by this experimental evidence, Rutherford outlined his model of the atom's structure, reasoning that as atoms clearly scattered incident alpha particles, the structure contained a much larger electrostatic force than earlier anticipated; as large angle scattering was a rare occurrence, the electrostatic charge source was only contained within a fraction of the total volume of the atom. As he concludes this reasoning with the "simplest explanation" in his 1911 paper, the "atom contains a central charge distributed through a very small volume" and "the large single deflexions are due to the central charge as a whole." In fact, he mathematically modeled the scattering patterns predicted by this model with this small central "nucleus" to be a point charge. Geiger and Marsden later experimentally verified each of the relationships predicted in Rutherford's mathematical model with techniques and scattering apparatuses that improved upon their prior work, confirming Rutherford's atomic structure. [4, 8, 9] (see Fig. 1)

With the experimentally analyzed nature of deflection of alpha rays by thin gold foil, the truth outlining the structure of the atom falls into place. Though later slightly corrected by Quantum Mechanics effects, the understanding of the structure of the the atom today almost entirely follows form Rutherford's conclusions on the Geiger and Marsden experiments. This landmark discovery fundamentally furthered all fields of science, forever changing mankind's understanding of the world around us.

© George Sivulka. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.

[1] E. Rutherford, "Uranium Radiation and the Electrical Conduction Produced By It," Philos. Mag. 47 , 109 (1899).

[2] E. Rutherford, "The Structure of the Atom," Philos. Mag. 27 , 488 (1914).

[3] J. J. Thomson, "On the Structure of the Atom: an Investigation of the Stability and Periods of Oscillation of a Number of Corpuscles Arranged at Equal Intervals Around the Circumference of a Circle; with Application of the Results to the Theory of Atomic Structure," Philos. Mag. 7 , 237 (1904).

[4] E. Rutherford, "The Scattering of α and β Particles by Matter and the Structure of the Atom," Philos. Mag. 21 , 669 (1911).

[5] H. Geiger, "On the Scattering of the α Particles by Matter," Proc. R. Soc. A 81 , 174 (1908).

[6] H. Geiger and E. Marsden, "On a Diffuse Reflection of the α-Particles," Proc. R. Soc. A 82 , 495 (1909).

[7] H. Geiger, "The Scattering of the α Particles by Matter," Proc. R. Soc. A 83 , 492 (1910).

[8] E. Rutherford, "The Origin of α and β Rays From Radioactive Substances," Philos. Mag. 24 , 453 (1912).

[9] H. Geiger and E. Marsden, "The Laws of Deflexion of α Particles Through Large Angles," Philos. Mag. 25 , 604 (1913).

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Who did the Gold Foil Experiment?

The gold foil experiment was a pathbreaking work conducted by scientists Hans Geiger and Ernest Marsden under the supervision of Nobel laureate physicist Ernest Rutherford that led to the discovery of the proper structure of an atom . Known as the Geiger-Marsden experiment, it was performed at the Physical Laboratories of the University of Manchester between 1908 and 1913.

The prevalent atomic theory at the time of the research was the plum pudding model that was developed by Lord Kelvin and further improved by J.J. Thomson. According to the theory, an atom was a positively charged sphere with the electrons embedded in it like plums in a Christmas pudding.

With neutrons and protons yet to be discovered, the theory was derived following the classical Newtonian Physics. However, in the absence of experimental proof, this approach lacked proper acceptance by the scientific community.

What is the Gold Foil Experiment?

Description.

The method used by scientists included the following experimental steps and procedure. They bombarded a thin gold foil of thickness approximately 8.6 x 10 -6 cm with a beam of alpha particles in a vacuum. Alpha particles are positively charged particles with a mass of about four times that of a hydrogen atom and are found in radioactive natural substances. They used gold since it is highly malleable, producing sheets that can be only a few atoms thick, thereby ensuring smooth passage of the alpha particles. A circular screen coated with zinc sulfide surrounded the foil. Since the positively charged alpha particles possess mass and move very fast, it was hypothesized that they would penetrate the thin gold foil and land themselves on the screen, producing fluorescence in the part they struck.

Like the plum pudding model, since the positive charge of atoms was evenly distributed and too small as compared to that of the alpha particles, the deflection of the particulate matter was predicted to be less than a small fraction of a degree.

Observation

Though most of the alpha particles behaved as expected, there was a noticeable fraction of particles that got scattered by angles greater than 90 degrees. There were about 1 in every 2000 particles that got scattered by a full 180 degree, i.e., they retraced their path after hitting the gold foil.

Simulation of Rutherford’s Gold Foil Experiment Courtesy: University of Colorado Boulder

The unexpected outcome could have only one explanation – a highly concentrated positive charge at the center of an atom that caused an electrostatic repulsion of the particles strong enough to bounce them back to their source. The particles that got deflected by huge angles passed close to the said concentrated mass. Most of the particles moved undeviated as there was no obstruction to their path, proving that the majority of an atom is empty.

In addition to the above, Rutherford concluded that since the central core could deflect the dense alpha particles, it shows that almost the entire mass of the atom is concentrated there. Rutherford named it the “nucleus” after experimenting with various gases. He also used materials other than gold for the foil, though the gold foil version gained the most popularity.

He further went on to reject the plum pudding model and developed a new atomic structure called the planetary model. In this model, a vastly empty atom holds a tiny nucleus at the center surrounded by a cloud of electrons. As a result of his gold foil experiment, Rutherford’s atomic theory holds good even today.

Rutherford’s Atomic Model

Rutherford’s Gold Foil Experiment Animation

• Rutherford demonstrated his experiment on bombarding thin gold foil with alpha particles contributed immensely to the atomic theory by proposing his nuclear atomic model.
• The nuclear model of the atom consists of a small and dense positively charged interior surrounded by a cloud of electrons.
• The significance and purpose of the gold foil experiment are still prevalent today. The discovery of the nucleus paved the way for further research, unraveling a list of unknown fundamental particles.
• Chemed.chem.purdue.edu
• Chem.libretexts.org
• Large.stanford.edu
• Radioa ctivity.eu.com

Article was last reviewed on Friday, February 3, 2023

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5 responses to “Gold Foil Experiment”

Super very much helpful to me,clear explanation about every act done by our Rutherford that is under different sub headings ,which is very much clear to ,to study .very much thanks to the science facts.com.thank u so much.

Good explanation,very helpful ,thank u ,so much

very clear and helpful, perfect for my science project!

Thank you for sharing the interactive program on the effects of the type of atom on the experiment! Looking forward to sharing this with my ninth graders!

Rutherford spearheaded with a team of scientist in his experiment of gold foil to capture the particles of the year 1911. It’s the beginning of explaining particles that float and are compacted . Rutherford discovered this atom through countless experiments which was the revolutionary discovery of the atomic nuclear . Rutherford name the atom as a positive charge and the the center is the nucleus.

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What is the Rutherford gold-foil experiment?

A piece of gold foil was hit with alpha particles , which have a positive charge. Most alpha particles went right through. This showed that the gold atoms were mostly empty space. Some particles had their paths bent at large angles. A few even bounced backward. The only way this would happen was if the atom had a small, heavy region of positive charge inside it.

Related Questions

Alpha particles and alpha radiation: Explained

Alpha particles are also known as alpha radiation.

What are alpha particles?

Rutherford's gold foil experiment explained, what is alpha decay and how does it happen, alpha radiation charge and penetrating power, uses of alpha radiation, dangers of alpha radiation, additional resources.

Alongside beta particles, gamma rays , and neutrons, alpha particles are a type of radiation, also called alpha radiation. As with most forms of radiation, alpha particles are emitted from radioactive elements.

Alpha particles are relatively heavy and slow compared to their companions, so they pose little danger to humans unless ingested. 

They are, however, frequently used in research — alpha particles were crucial in Ernest Rutherford's discovery of the atomic nucleus, which was the foundation of his atomic model.

Alpha particles are positively charged particles that comprise two protons, two neutrons, and zero electrons . A single particle's mass is 4 amu (6.642×10−4 g),  according to Britannica  Alpha particles are emitted from heavy radioactive elements (both naturally occurring and man-made), including uranium, radium, and plutonium. Because of this, these elements are also called alpha emitters.

An alpha particle is commonly represented by the symbol α, the Greek letter alpha for which the particle is named. It was the first type of nuclear radiation to be discovered, before beta particles and gamma rays. But because an alpha particle is identical to the nucleus of a helium-4 atom, it is sometimes represented as He2+, that is, a doubly ionized helium-4 atom. 

Between 1898 and 1899, physicist Ernest Rutherford, who was studying radioactivity at Cambridge University in England, determined that there were at least two types of radiation , which he named alpha and beta. The alpha particle would lead to his discovery of the atomic nucleus — and help him develop the Rutherford atomic model, a radical shift in humanity's understanding of atoms .

In 1911, Rutherford officially published a paper declaring the existence of a positively charged nucleus at the center of an atom (though he didn't formally call it a nucleus at this point). Since 1907, Rutherford, Hans Geiger, and Ernest Marsden had been performing a series of Coulomb scattering experiments at the University of Manchester in England. Those experiments involved shooting alpha particles at thin gold foil, then observing where those particles went after colliding with the foil.

At the time, J. J. Thompson's "plum pudding" atomic model was the dominant theory of atomic structure — it suggested atoms were perfect spheres of positively charged material in which negative electrons floated about with relatively even distribution.

If that model were true, alpha particles would have passed through the foil in Rutherford's Coulomb experiments. But Rutherford and his colleagues observed that a few of the alpha particles bounced off the foil in different directions. Rutherford then theorized that atoms had a dense nucleus surrounded by orbiting electrons — the alpha particles went through the space between the electrons and bounced off the nucleus.

Alpha decay is the process by which alpha particles are formed , according to Britannica. Unstable radioactive elements called radionuclides emit particles from their nuclei to become more stable, transforming from the original element into a new one. Those emissions are radiation — in the case of alpha decay, alpha particles are emitted from the nuclei of heavy radioactive elements. 

Alpha radiation has a positive charge of two. Of the main types of radiation, alpha particles are the heaviest and slowest, with a mass of 4 amu and ejection speeds of approximately 12,400 miles per second (20,000,000 km per second) according to the Australian Radiation Protection and Nuclear Safety Agency .

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Despite being highly energetic, alpha particles expend most of that energy immediately after emission, so they do not travel farther than a few inches at most. They also have extremely low penetrating power — they cannot penetrate a human's epidermis, or outer layer of skin. Even a piece of paper is enough to block an alpha particle per the United States Nuclear Regulatory Committee .

Commercially, alpha radiation is primarily used in smoke detectors (smoke reduces the alpha particles in the detector, triggering the alarm) and static eliminators (alpha ionizers). 

There is also ongoing research into developing alpha-particle therapy to treat cancer — clinical trials have found some success in treating metastatic, castration-resistant prostate cancer. For research purposes, alpha particles are used as projectiles, as in the case of Rutherford's gold foil experiment. 

Alpha radiation is not dangerous to humans externally due to its low penetrating power; alpha particles cannot penetrate your skin. They can, however, cause damage to your cornea . 

The real danger occurs inside the body. If an alpha emitter (that is, a radioactive element) enters your body via ingestion, inhalation, a wound, or any other means, great damage could be done internally to living tissue. 

Read more about Rutherford's work with alpha particles in this online exhibition by the American Institute of Physics' Center for History. You can also learn more on his biography page from the Nobel Foundation — Rutherford was awarded the Nobel Prize in Chemistry in 1908 "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances." 

Bibliography

Australian Radiation Protection and Nuclear Safety Agency ( ARPANSA ), "Alpha particles." 

Britannica, "Alpha decay." 

Britannica , "Alpha particle." 

United States Environmental Protection Agency (EPA), "Radiation Basics." 

United States Nuclear Regulatory Commission (USNRC), " Radiation Basics. " 

Center for History, American Institute of Physics, " Rutherford's Nuclear World ."  

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• Alpha-Particle Scattering and Rutherford’s Nuclear Model of Atom

In 1911, Rutherford, along with his assistants, H. Geiger and E. Marsden, performed the Alpha Particle scattering experiment , which led to the birth of the ‘nuclear model of an atom ’ – a major step towards how we see the atom today.

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J.j thomson’s plum-pudding model.

In 1897-98, the first model of an atom was proposed by J.J. Thomson. Famously known as the Plum-pudding model or the watermelon model, he proposed that an atom is made up of a positively charged ball with electrons embedded in it. Further, the negative and positive charges were equal in number , making the atom electrically neutral.

Figure 1 shows what Thomson’s plum-pudding model of an atom looked like. Ernest Rutherford, a former research student working with J.J. Thomson, proposed an experiment of scattering of alpha particles by atoms to understand the structure of an atom.

Rutherford, along with his assistants – H. Geiger and E. Marsden – started performing experiments to study the structure of an atom. In 1911, they performed the Alpha particle scattering experiment, which led to the birth of the ‘nuclear model of an atom’ – a major step towards how we see the atom today.

Figure 1. Source: Wikipedia

Browse more Topics under Atoms

• Atomic Spectra
• Bohr Model of the Hydrogen Atom

The Alpha Particle Scattering Experiment

They took a thin gold foil having a thickness of 2.1×10 -7 m and placed it in the centre of a rotatable detector made of zinc sulfide and a microscope. Then, they directed a beam of 5.5MeV alpha particles emitted from a radioactive source at the foil. Lead bricks collimated these alpha particles as they passed through them.

After hitting the foil, the scattering of these alpha particles could be studied by the brief flashes on the screen. Rutherford and his team expected to learn more about the structure of the atom from the results of this experiment.

Source: Wikipedia

Observations

Here is what they found:

• Most of the alpha particles passed through the foil without suffering any collisions
• Around 0.14% of the incident alpha particles scattered by more than 1 o
• Around 1 in 8000 alpha particles deflected by more than 90 o

These observations led to many arguments and conclusions which laid down the structure of the nuclear model on an atom.

Conclusions and arguments

The results of this experiment were not in sync with the plum-pudding model of the atom as suggested by Thomson. Rutherford concluded that since alpha particles are positively charged, for them to be deflected back, they needed a large repelling force. He further argued that for this to happen, the positive charge of the atom needs to be concentrated in the centre, unlike scattered in the earlier accepted model.

Hence, when the incident alpha particle came very close to the positive mass in the centre of the atom, it would repel leading to a deflection. On the other hand, if it passes through at a fair distance from this mass, then there would be no deflection and it would simply pass through.

He then suggested the ‘nuclear model of an atom’ wherein the entire positive charge and most of the mass of the atom is concentrated in the nucleus. Also, the electrons are moving in orbits around the nucleus akin to the planets and the sun. Further, Rutherford also concluded from his experiments that the size of the nucleus is between 10 -15 and 10 -14 m.

According to Kinetic theory, the size of an atom is around 10 -10 m or around 10,000 to 100,000 times the size of the nucleus proposed by Rutherford. Hence, the distance of the electrons from the nucleus should be around 10,000 to 100,000 times the size of the nucleus.

This eventually implies that most of the atom is empty space and explains why most alpha particles went right through the foil. And, these particles are deflected or scattered through a large angle on coming close to the nucleus. Also, the electrons having negligible mass, do not affect the trajectory of these incident alpha particles.

Alpha Particle Trajectory

The trajectory traced by an alpha particle depends on the impact parameter of the collision. The impact parameter is simply the perpendicular distance of each alpha particle from the centre of the nucleus. Since in a beam all alpha particles have the same kinetic energy, the scattering of these particles depends solely on the impact parameter.

Hence, the particles with a small impact parameter or the particles closer to the nucleus, experience large angle of scattering. On the other hand, those with a large impact parameter suffer no deflection or scattering at all. Finally, those particles having ~zero impact parameter or a head-on collision with the nucleus rebound back.

Coming to the experiment, Rutherford and his team observed that a really small fraction of the incident alpha particles was rebounding back. Hence, only a small number of particles were colliding head-on with the nucleus. This, subsequently, led them to believe that the mass of the atom is concentrated in a very small volume.

Electron Orbits

In a nutshell, Rutherford’s nuclear model of the atom describes it as:

• A small and positively charged nucleus at the centre
• Surrounded by revolving electrons in their dynamically stable orbits

The centripetal force that keeps the electrons in their orbits is an outcome of:

• The positively charged nucleus and
• The negatively charged revolving electrons.

Solved Example for You

Question: Rutherford, Geiger and Marsden, directed a beam of alpha particles on a foil of which metal

Solution: Gold

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Before Ernest Rutherford's landmark experiment with a few pieces of metal foil and alpha particles, the structure of the atom was thought to correspond with the plum pudding model. In summary, the plum pudding model was hypothesized by J.J. Thomson (the discoverer of the electron) who described an atom as being a large positively charged body that contained small, free–floating, negatively charged particles called electrons. The plum pudding model also states that the negative charge of the electrons is equivalent to the positive charge of the rest of the atom. The two charges cancel each other and cause the electrical charge of the atom to be zero (or neutral). The faulty aspect of this model is that it was constructed before the nucleus of an atom (and it's composition) was discovered, which is where Rutherford's research comes in.

In 1911, Ernest Rutherford conducted an experiment that proved that the mass of an atom is concentrated in the center (nucleus) of an atom. It also proved that an atom is mostly empty space.

When he shot a beam of alpha particles at a sheet of gold foil, a few of the particles were deflected. He concluded that a tiny, dense nucleus was causing the deflections.

Rutherford carried out a series of experiments using very thin foils of gold and other metals as targets for a particles from a radioactive source. They observed that the majority of particles penetrated the foil either undeflected or with only a slight deflection. But every now and then a particle was scattered (or deflected) at a large angle. In some instances, a particle actually bounced back in the direction from which it had come! This was a most surprising finding, in Thomson's model the positive charge of the atom was so diffuse that the positive a particles should have passed through the foil with very little deflection.

Rutherford was later able to explain the results of the α-scattering experiment in terms of a new model for the atom. According to Rutherford, most of the atom must be empty space. This explains why the majority of a particles passed through the gold foil with little or no deflection. The atom's positive charges, Rutherford proposed, are all concentrated in the nucleus, which is a dense central core within the atom. Whenever a particle came close to a nucleus in the scattering experiment, it experienced a large repulsive force and therefore a large deflection. Moreover, a particle traveling directly towards a nucleus would be completely repelled and its direction would be reversed.

Rutherford Explanations on gold foil experiment :

• Since most of the alpha particles pass straight through the gold foil without any deflection, it shows there is a lot of empty space in an atom.
• Those positively charged alpha particles deflected by large angles–some even backward, nearly in the direction from which they had come, which shows that there is a positive charge in center which is not distributed uniformly inside the atom.

• Around 1 in 8000 alpha particles were deflected by very large angles (over 90°), while the rest passed straight through with little or no deflection. From this, Rutherford concluded that the majority of the mass was concentrated in a central core.
• An atom has a tiny positively charged core (nucleus) which contains most of the mass over 99.9% of the mass of the atom.
• The electrons revolve around the nucleus in circular paths similar to the planets revolve around the Sun (solar system). The electrostatic force of attraction between the nucleus and electron provides centripetal force.
• He estimated that the radius of the nucleus was at least 1/100000 times smaller than that of the radius of the atom. Scientists imagined the size of the nucleus with the following similarity, if the size of the atom is that of Earth then the nucleus would have the size of an apple.
• The amount of positive charge in the nucleus is equal to the amount of negative charge on the electrons. So, the atom as a whole is electrically neutral.

One of the most important limitation of Rutherford model is that Rutherford's model failed to explain stability of atoms or why electrons which revolve around the nucleus do not lose energy and finally fall into the nucleus. Stability of atoms is explained by Bohr model of atom.

Rutherford Scattering ( AQA GCSE Physics )

Revision note.

Physics Project Lead

Rutherford Scattering

Alpha scattering.

• Physicist, Ernest Rutherford was instructing two of his students, Hans Geiger and Ernest Marsden to carry out the experiment
• They were directing a beam of alpha particles (He 2+ ions) at a thin gold foil
• They expected the alpha particles to travel through the gold foil, and maybe change direction a small amount
• Most of the alpha particles passed straight through the foil
• Some of the alpha particles changed direction but continued through the foil
• A few of the alpha particles bounced back off the gold foil
• The bouncing back could not be explained by the Plum Pudding model, so a new model had to be created

When alpha particles are fired at thin gold foil, most of them go straight through, some are deflected and a very small number bounce straight back

The Nuclear Model

• Ernest Rutherford made different conclusions from the findings of the experiment
• The table below describes the findings and conclusions of A, B and C from the image above:

Alpha Scattering Findings and Conclusions Table

• Rutherford proposed the nuclear model of the atom
• Nearly all of the mass of the atom is concentrated in the centre of the atom (in the nucleus)
• The nucleus is positively charged
• Negatively charged electrons orbit the nucleus at a distance
• The nuclear model could explain experimental observations better than the Plum Pudding model

The Nuclear model replaced the Plum Pudding model as it could better explain the observations of Rutherford’s Scattering Experiment

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August 26, 2024

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Experiment sets new record in search for dark matter

by Lauren Biron, Lawrence Berkeley National Laboratory

Figuring out the nature of dark matter, the invisible substance that makes up most of the mass in our universe, is one of the greatest puzzles in physics. New results from the world's most sensitive dark matter detector, LUX-ZEPLIN (LZ), have narrowed down possibilities for one of the leading dark matter candidates: weakly interacting massive particles, or WIMPs.

LZ, led by the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), hunts for dark matter from a cavern nearly one mile underground at the Sanford Underground Research Facility in South Dakota. The experiment's new results explore weaker dark matter interactions than ever researched before and further limit what WIMPs could be.

"These are new world-leading constraints by a sizable margin on dark matter and WIMPs," said Chamkaur Ghag, spokesperson for LZ and a professor at University College London (UCL). He noted that the detector and analysis techniques are performing even better than the collaboration expected.

"If WIMPs had been within the region we searched, we'd have been able to robustly say something about them. We know we have the sensitivity and tools to see whether they're there as we search lower energies and accrue the bulk of this experiment's lifetime."

The collaboration found no evidence of WIMPs above a mass of 9 gigaelectronvolts/c 2 (GeV/c 2 ). (For comparison, the mass of a proton is slightly less than 1 GeV/c 2 .) The experiment's sensitivity to faint interactions helps researchers reject potential WIMP dark matter models that don't fit the data, leaving significantly fewer places for WIMPs to hide.

The new results were presented at two physics conferences on August 26: TeV Particle Astrophysics 2024 in Chicago, Illinois, and LIDINE 2024 in São Paulo, Brazil. A paper will be published in the coming weeks.

The results analyze 280 days' worth of data: a new set of 220 days (collected between March 2023 and April 2024) combined with 60 earlier days from LZ's first run. The experiment plans to collect 1,000 days' worth of data before it ends in 2028.

"If you think of the search for dark matter like looking for buried treasure, we've dug almost five times deeper than anyone else has in the past," said Scott Kravitz, LZ's deputy physics coordinator and a professor at the University of Texas at Austin. "That's something you don't do with a million shovels—you do it by inventing a new tool."

LZ's sensitivity comes from the myriad ways the detector can reduce backgrounds, the false signals that can impersonate or hide a dark matter interaction. Deep underground, the detector is shielded from cosmic rays coming from space.

To reduce natural radiation from everyday objects, LZ was built from thousands of ultraclean, low-radiation parts. The detector is built like an onion, with each layer either blocking outside radiation or tracking particle interactions to rule out dark matter mimics. And sophisticated new analysis techniques help rule out background interactions, particularly those from the most common culprit: radon.

This result is also the first time that LZ has applied "salting"—a technique that adds fake WIMP signals during data collection. By camouflaging the real data until "unsalting" at the very end, researchers can avoid unconscious bias and keep from overly interpreting or changing their analysis.

"We're pushing the boundary into a regime where people have not looked for dark matter before," said Scott Haselschwardt, the LZ physics coordinator and a recent Chamberlain Fellow at Berkeley Lab who is now an assistant professor at the University of Michigan. "There's a human tendency to want to see patterns in data, so it's really important when you enter this new regime that no bias wanders in. If you make a discovery, you want to get it right."

Dark matter, so named because it does not emit, reflect, or absorb light, is estimated to make up 85% of the mass in the universe but has never been directly detected, though it has left its fingerprints on multiple astronomical observations. We wouldn't exist without this mysterious yet fundamental piece of the universe; dark matter's mass contributes to the gravitational attraction that helps galaxies form and stay together.

LZ uses 10 tons of liquid xenon to provide a dense, transparent material for dark matter particles to potentially bump into. The hope is for a WIMP to knock into a xenon nucleus, causing it to move, much like a hit from a cue ball in a game of pool. By collecting the light and electrons emitted during interactions, LZ captures potential WIMP signals alongside other data.

"We've demonstrated how strong we are as a WIMP search machine, and we're going to keep running and getting even better—but there's lots of other things we can do with this detector," said Amy Cottle, lead on the WIMP search effort and an assistant professor at UCL.

"The next stage is using these data to look at other interesting and rare physics processes, like rare decays of xenon atoms, neutrinoless double beta decay, boron-8 neutrinos from the sun, and other beyond-the-Standard-Model physics. And this is in addition to probing some of the most interesting and previously inaccessible dark matter models from the last 20 years."

LZ is a collaboration of roughly 250 scientists from 38 institutions in the United States, United Kingdom, Portugal, Switzerland, South Korea, and Australia; much of the work building, operating, and analyzing the record-setting experiment is done by early career researchers.

The collaboration is already looking forward to analyzing the next data set and using new analysis tricks to look for even lower-mass dark matter. Scientists are also thinking through potential upgrades to further improve LZ, and planning for a next-generation dark matter detector called XLZD.

"Our ability to search for dark matter is improving at a rate faster than Moore's Law," Kravitz said. "If you look at an exponential curve, everything before now is nothing. Just wait until you see what comes next."

Provided by Lawrence Berkeley National Laboratory

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Notes from the Field

The arctic radiation-cloud-aerosol-surface interaction experiment (arcsix) in greenland.

May 25, 2024 Some 25 of us were up before 6 a.m. to head out on the bus from the hotel to Burlington International Airport to catch the C-130 aircraft, a military transport plane repurposed for NASA fieldwork, to begin our 7-hour flight to Pituffik.

Several mountains of baggage, including scientific instruments and personal luggage, separate us from the less-well-heated economy cabin, which was probably reserved for graduate students, though we are far too collegial a group to check seat assignments. As we head north and east, the landscape out the window is vast, entirely gray-scale, and unforgiving: sea ice with streaks and patches of open water as far as one can see in every direction.

About halfway through the flight, we cross the Arctic Circle. Here the scene is often reduced to pure gray, and one cannot tell what is sea ice, snow, or cloud. This is the challenge we have long faced when attempting to interpret our remote sensing imagery; now, as an early gift of the expedition, I experience it directly.

May 26, 2024

The site is halfway between Washington and Moscow. Most or all of the buildings were prefabricated, brought here by ship in the summer, and mounted on stilts due to the permafrost. Some rough grasses are the only apparent vegetation.

In some ways, the base is well appointed. There is a sports center with an abundance of every conceivable exercise machine, also a tanning machine and a perpetual pool, a huge gym, and a yoga room. There is a recreation center with a movie theater, a lounge area with free apples, tea, and coffee, a game room that is more like an arcade with multiple video machines, and a craft center that has sewing machines (including a state-of-the-art Serger), rock cutting and polishing machines, computer graphics, and printers.

This is a remote place. The site is protected by a thousand kilometers of ice in nearly all directions, and the only ways to get here are by air or by boat for a couple of months of the year, when the sea is not frozen. With full daylight all day and “night,” the times-of-day are marked only by artificial clocks; the natural ones are essentially absent.

May 27, 2024

This was mostly a flight-planning day, getting ready for the first science flight of the campaign. It turned cold, windy, and snow fell today. This was more like what I expected but didn’t experience during the first two days. But now it is sunny again, around 6 p.m., and near-freezing, so there is still standing water on the roadways, and we are past the season when it is safe to walk on the ice-bound bay. The severe environment calls for some specific adaptations.

For example, the outer doors have latches that seal upward, so a bear pushing down on the handle will be unable to open the door. The walkways are made of open steel grids, so snow and mud will drip through. Boots are to be brushed before entering buildings, and plastic boot covers are provided in an effort to limit the amount of dirt that is tracked in.

I took a late-night walk. It’s daylight anyway, though overcast, windy, cold, and flurrying. Pretty much what I expected here. 

The power went out twice today. Everything goes down, including the internet. I’m trying to keep everything charged, in case it happens again. Today’s weather represents “Condition Alpha” for storm warnings. That means just be on alert, in case things change. Condition Bravo means you cannot go outdoors without a buddy, or drive alone without a radio. Condition Charlie means you can’t walk out at all; there is a base taxi for urgent movement. Condition Delta: shelter in place. 

The pipes are all above-ground because of the freeze-thaw cycle that would destroy the pipes. I guess they must be heated and insulated. They cross the road by going overhead. 

Car and truck engines must be heated to avoid freezing and cracking. So, many of the buildings have power cords hanging out in front to run electric engine-block heaters. I didn’t take the last picture quite at midnight, but the scene doesn’t change much during the night.

I think I mentioned that it is mud season here. This is no joke. The place has a very industrial feel, and the only place to walk is on the mud roads. I’ve heard it will get worse as the mud deepens, and mosquitoes come out. Something to look forward to…

May 28, 2024

We had our first flight with the P3 today, and it was far better than I had expected. There was a rare case of cloud-free atmosphere over sea ice in one area north of Greenland where some buoys had been deployed, which allowed for both surface ice and aerosol characterization. Also, a nearly 3-hour run at ~500 feet captured aerosol properties over open water along the northern part of Baffin Bay. Among our objectives are learning the sources and properties of aerosols in the Arctic, their evolution as they age, and their impact on clouds. Others are especially interested in the properties of sea ice as it melts. So, this gives us a start on those objectives.

May 29, 2024

The wind is a force of nature. Today it has been blowing at something like 40 miles per hour, with gusts considerably higher. It literally takes your breath away—and this is just Condition Alpha. 

Gusts create the sensation of blowing you away. All this under a relatively clear sky, bright sun, just a few clouds. It is somewhat other-worldly to one who has lived a life at lower latitudes. The temperature is only a few degrees below freezing, but the weather today gives new meaning to the term “wind chill.” 

June 1, 2024

Today was an official day off, and in particular, a mental health day for the forecasters. Several of the military folks on the base arranged to take a group of us on a hike over the Greenland Ice Cap. There were 15 of us in five trucks. The trip involved a fair amount of driving on gravel roads in trucks—about half the time driving, half hiking – 5 hours total. The hike itself was about 5 or 6 miles, and we walked around and then on the glacier, though we never did find the Starbucks.

In addition to the stark beauty of the rock fields and ice, the sky is unlike anything we normally see at lower latitudes. The surface is cold, and the atmosphere is no colder (and sometimes is even warmer) than the surface, i.e., it is stably stratified—the “warm” air is already up, so there is not a lot of warm air rising and mixing that typically happens when the surface is heated directly by the Sun.

The glaciers have brought an enormous diversity of stones that litter the ground, and every piece of wood here was carried in from somewhere else. There are little clumps of vegetation, just enough to satisfy the appetites of musk oxen. 

So far, I’ve seen Arctic fox (no pictures—they disappeared too quickly), musk ox in the distance, Arctic hare, and snow goose. No polar bears—and no complaints about that. 

June 7, 2024

This evening I took a long walk out to the ice-bound pier… AND I SAW AN OTTER!!!

June 4, 2024

The Arctic foxes are molting. They were very cute when their coats were all white. Now they are losing their winter coats and turning brown. I did see a couple of full white coats, but was too slow to get a photo. 

June 8, 2024

The project rented a van, and ten of us went off to climb the Dundas, that imposing rock feature not far from the base, though to get there without walking on thin ice (here the term is not merely a metaphor), one has to drive about 30 minutes over rocky and sometimes quite steep roads around the frozen bay.

The angle of repose is the angle a pile of dry sand (or salt) will make if you dump a bucket of it on the ground. It is generally steep (depends in part on the grain size and shape of the sand particles). Dundas is about 725 feet high; it appears to be the remnant of a glacial moraine—rock pushed here by an advancing ice sheet at least that high, that remained after the ice melted away. It is loose sand and rock, mostly gravel and cobble-sized. The climb up was, frankly, arduous, as there are not a lot of footholds. 

The first part was steep enough that going on all fours was necessary in places, and the sand and small rocks would slip easily down the slope as one persevered upward. The final part was up a sheer rock wall that was graced, mercifully, with a sturdy rope. My pictures are lacking for the entire traverse, as all my effort went into the climb itself. I did stop part way up the rock wall to check my life insurance policy.

 The view from the top was spectacular, but truthfully, there are so many great vistas in this rugged place that the main reward was accomplishing the ascent itself. 

The way down was similarly fraught, except that below the rock wall, I had pretty much no choice but to slide down bit by bit—the loose surface material would give way at every step. So, on my back, lift up my rear, slide a few feet using my boots to stop, and repeat. There was some interesting vegetation on the slope—tiny plants and lichen, which I did photograph. I’m told that some of these plants can be hundreds of years old. 

In the distance, we saw some dark spots that the binoculars suggested were seals. (Oh, yes—someone here said that my otter from last night was actually a ring seal; not sure that is authoritative, but…).

June 9, 2024

I agreed to join this afternoon’s walk up the edge of the Greenland Ice Sheet. 

The slope is moderate by Dundas standards, and the path is completely snow-covered. The walk up is of course uphill, and a steady wind of 30–40 mph (the katabatic wind), with significantly higher gusts, blows off the ice. This guaranteed that however far we got up the ice sheet, we would certainly be able to make it down, either on foot or airborne.

There were pools of water within ice basins at the base. They look a beautiful shade of blue. We saw this in Alaska as well. I think it must be that ice either absorbs all the longer wavelengths, or it preferentially scatters blue, or both. The optics here are stunning, at least to me. Probably because they are unfamiliar. 

One way painters provide a sense of distance in a painting is with “atmospherics,” that is, they increasingly blur the edges of more distant objects to account for light scattering by atmospheric gas and aerosols. Mountain climbers experience the opposite, in the thinner atmosphere, remote objects are sharper than they would in everyday experience, so more distant objects appear closer than they actually are. This is true here in Greenland as well, though we are not at a very high elevation along the coast. I expect the phenomenon in this case is due to a very clean atmosphere. 

June 11, 2024 Today I got to fly on the P-3. Every satellite scientist should be required to take at least one such flight to see what the Earth is really like. We flew across northern Greenland and over sea ice. In the two weeks since the campaign deployment began, the depth of the sea ice, and the snow upon it, both decreased at those buoys (where it was measured), and, of course, most everywhere else as well.

A field campaign is a layered operation. Aircraft flight scientists build, run, and maintain the twenty or so instruments that measure particle composition, gas concentration, cloud properties, surface reflectivity, and upwelling and downwelling energy. They are awake by 4 a.m. to prepare their instruments for flight, worry about power supplies and calibration, then sit on the plane for six or seven hours, noting what they see from their measurements and out the window.

The number of leads (i.e., openings in the ice) has increased in places. We flew at high elevation to survey the area, measure the overall surface topography and reflectance, and sample aerosol layers aloft, then descended to 300 feet above the ice to capture aerosols emanating from the surface. The photos tell an accessible part of the story. The rest must be teased out of the data in the coming months and years. But my ride is over for now—there is an aerosol forecast due tomorrow.

June 12, 2024

It was flurrying this evening, and my walk carried me down toward the pier. But you might be pleased to know, I did not go all the way; several seals have now been seen on the ice at the pier. My otter or seal in the water was the first anyone saw, and although they say it is relatively rare for bears to go near the base, seals are their primary food. I figured, after a long winter hibernation, a bear might not count me as even a light snack, but in consideration that I had already booked my flight home, I turned around before getting very near the water’s edge. 

June 14, 2024

I should say that the food here is okay. Better than I expected. Of course, in such circumstances, it pays to begin with low expectations: hardtack, pemmican, and beef jerky. The cafeteria serves a lot of beef and pork, but there is also chicken, a reasonable salad bar, excellent, fresh bread (the highlight in my opinion), always two of THE three kinds of fruit (apples, oranges, and bananas—so yes, they mix apples and oranges), and of course, Danish, at least in the morning. 

In the evening I took a walk, as usual, and ended up in one of the dozens of prefab buildings on the base, with the suggestive label “Heritage Hall.” The door was not locked, and the lights turned on as you entered each room. The place is a sort of museum, a repository for things discarded from the 1950s and 60s.

They have a computer punch-card machine, a vacuum-tube TV set, and a radar scope you will recognize from science-fiction movies. Also some notebooks with photos of the army’s Camp Tuto (now abandoned—only remnants of the airfield remain) and the presumptive city “Camp Century” they built into the ice in the 1950s. The walls flowed at glacial speed but ultimately collapsed.

Thule base was established in 1951, succeeding three waves of Inuit who inhabited the area, apparently beginning 4,500 years ago. The most recent came around 900 CE, met the Norse about 100 years later, and were moved to a new village 60 miles to the north in 1953. There is even a Life Magazine cover showing ships delivering material to the base in September 1952. 

Ralph Kahn , an emeritus research scientist at NASA’s Goddard Space Flight Center now at the Laboratory for Atmospheric and Space Physics at the University of Colorado Boulder, spent three weeks at Pituffik Space Base in northern Greenland in the summer of 2024. He was one of dozens of scientists who participated in ARCSIX ( Arctic Radiation-Cloud Aerosol-Surface Interaction Experiment ), a NASA-sponsored field campaign that made detailed observations of clouds and atmospheric particles to better understand the processes that affect the seasonal melting of Arctic sea ice. These excerpts from his emails home to family provide a glimpse of what life was like on one of the world’s most northern scientific outposts in the world. Photos were taken by Kahn or Gary Banzinger, a NASA videographer who also participated in the campaign. Kahn, an atmospheric scientist, worked with colleagues to provide daily aerosol forecasts that were used to help plan flights.

Tags: aerosols , climate change , clouds , Greenland , ice , NASA , sea ice

This entry was posted on Friday, August 23rd, 2024 at 3:40 pm and is filed under Arctic Radiation Cloud Aerosol Surface Interaction Experiment (ARCSIX) . You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

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Effects of high-grain diet on performance, ruminal fermentation, and rumen microbial flora of lactating holstein dairy cows.

Simple Summary

1. introduction, 2. materials and methods, 2.1. experimental design and animal management, 2.2. sample collection and analyses, 2.3. dna extraction and 16s rrna gene sequencing, 2.4. bioinformatics analysis of the sequence data, 2.5. statistical analysis, 3.1. feed intake and lactation performance, 3.2. ruminal fermentation characteristics, 3.3. sequencing and diversity measures, 3.4. ruminal microbiota composition, 3.5. correlation analysis of rumen fermentation parameters and major bacteria, 3.6. functional prediction of the microbial community structure, 4. discussion, 5. conclusions, supplementary materials, author contributions, institutional review board statement, informed consent statement, data availability statement, conflicts of interest.

• Luo, D.; Gao, Y.; Lu, Y.; Qu, M.; Xiong, X.; Xu, L.; Zhao, X.; Pan, K.; Ouyang, K. Niacin alters the ruminal microbial composition of cattle under high-concentrate condition. Anim. Nutr. 2017 , 3 , 180–185. [ Google Scholar ] [ CrossRef ]
• Plaizier, J.C.; Krause, D.O.; Gozho, G.N.; McBride, B.W. Subacute ruminal acidosis in dairy cows: The physiological causes, incidence and consequences. Vet. J. 2008 , 176 , 21–31. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Dai, H.; Ma, N.; Chang, G.; Aabdin, Z.U.; Shen, X. Long-term high-concentrate diet feeding induces apoptosis of rumen epithelial cells and inflammation of rumen epithelium in dairy cows. Anim. Biotechnol. 2022 , 33 , 289–296. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Zhang, R.; Ye, H.; Liu, J.; Mao, S. High-grain diets altered rumen fermentation and epithelial bacterial community and resulted in rumen epithelial injuries of goats. Appl. Microbiol. Biotechnol. 2017 , 101 , 6981–6992. [ Google Scholar ] [ CrossRef ]
• Gomez, D.E.; Arroyo, L.G.; Costa, M.C.; Viel, L.; Weese, J.S. Characterization of the Fecal Bacterial Microbiota of Healthy and Diarrheic Dairy Calves. J. Vet. Intern. Med. 2017 , 31 , 928–939. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• McCann, J.C.; Elolimy, A.A.; Loor, J.J. Rumen Microbiome, Probiotics, and Fermentation Additives. Vet. Clin. N. Am. Food Anim. Pract. 2017 , 33 , 539–553. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Li, Y.; Ma, N.; Ren, L.; Wang, M.; Hu, L.; Shen, Y.; Cao, Y.; Li, Q.; Li, J.; Gao, Y. Microbiome-Metabolome Responses in Ruminal Content and Feces of Lactating Dairy Cows With N-Carbamylglutamate Supplementation Under Heat Stress. Front. Vet. Sci. 2022 , 9 , 902001. [ Google Scholar ] [ CrossRef ]
• Steele, M.A.; Penner, G.B.; Chaucheyras-Durand, F.; Guan, L.L. Development and physiology of the rumen and the lower gut: Targets for improving gut health. J. Dairy Sci. 2016 , 99 , 4955–4966. [ Google Scholar ] [ CrossRef ]
• NRC. Nutrient Requirements of Dairy Cattle ; National Academies Press: Washington, DC, USA, 2021; p. 502. [ Google Scholar ]
• Jiang, M.C.; Datsomor, O.; Cheng, Z.Q.; Meng, Z.T.; Zhan, K.; Yang, T.Y.; Huang, Y.H.; Yan, Q.; Zhao, G.Q. Partial Substitution of Alfalfa Hay by Stevia ( Stevia rebaudiana ) Hay Can Improve Lactation Performance, Rumen Fermentation, and Nitrogen Utilization of Dairy Cows. Front. Vet. Sci. 2022 , 9 , 899148. [ Google Scholar ] [ CrossRef ]
• Jiang, M.C.; Zhang, X.L.; Wang, K.X.; Datsomor, O.; Li, X.; Lin, M.; Feng, C.Y.; Zhao, G.Q.; Zhan, K. Effect of Slow-Release Urea Partial Replacement of Soybean Meal on Lactation Performance, Heat Shock Signal Molecules, and Rumen Fermentation in Heat-Stressed Mid-Lactation Dairy Cows. Animals 2023 , 13 , 2771. [ Google Scholar ] [ CrossRef ]
• Wolff, S.M.; Ellison, M.J.; Hao, Y.; Cockrum, R.R.; Austin, K.J.; Baraboo, M.; Burch, K.; Lee, H.J.; Maurer, T.; Patil, R.; et al. Diet shifts provoke complex and variable changes in the metabolic networks of the ruminal microbiome. Microbiome 2017 , 5 , 60. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Wu, Z.Z.; Peng, W.C.; Liu, J.X.; Xu, G.Z.; Wang, D.M. Effect of chromium methionine supplementation on lactation performance, hepatic respiratory rate and anti-oxidative capacity in early-lactating dairy cows. Anim. Int. J. Anim. Biosci. 2021 , 15 , 100326. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Chen, S.F.; Zhou, Y.Q.; Chen, Y.R.; Gu, J. fastp: An ultra-fast all-in-one FASTQ preprocessor. Bioinformatics 2018 , 34 , 884–890. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Edgar, R.C. UPARSE: Highly accurate OTU sequences from microbial amplicon reads. Nat. Methods 2013 , 10 , 996–998. [ Google Scholar ] [ CrossRef ]
• Nilsson, R.H.; Larsson, K.H.; Taylor, A.F.S.; Bengtsson-Palme, J.; Jeppesen, T.S.; Schigel, D.; Kennedy, P.; Picard, K.; Glockner, F.O.; Tedersoo, L.; et al. The UNITE database for molecular identification of fungi: Handling dark taxa and parallel taxonomic classifications. Nucleic Acids Res. 2019 , 47 , D259–D264. [ Google Scholar ] [ CrossRef ]
• Altschul, S.F.; Gish, W.; Miller, W.; Myers, E.W.; Lipman, D.J. Basic local alignment search tool. J. Mol. Biol. 1990 , 215 , 403–410. [ Google Scholar ] [ CrossRef ]
• Ondov, B.D.; Bergman, N.H.; Phillippy, A.M. Interactive metagenomic visualization in a Web browser. BMC Bioinform. 2011 , 12 , 385. [ Google Scholar ] [ CrossRef ]
• Cao, T.; Li, Q.; Huang, Y.; Li, A. plotnineSeqSuite: A Python package for visualizing sequence data using ggplot2 style. BMC Genom. 2023 , 24 , 585. [ Google Scholar ] [ CrossRef ]
• Spindel, J.; Begum, H.; Akdemir, D.; Virk, P.; Collard, B.; Redona, E.; Atlin, G.; Jannink, J.L.; McCouch, S.R. Genomic selection and association mapping in rice ( Oryza sativa ): Effect of trait genetic architecture, training population composition, marker number and statistical model on accuracy of rice genomic selection in elite, tropical rice breeding lines. PLoS Genet. 2015 , 11 , e1004982. [ Google Scholar ] [ CrossRef ]
• Liu, X.; Wang, L.; Zhuang, H.; Yang, Z.; Jiang, G.; Liu, Z. Promoting intestinal IgA production in mice by oral administration with anthocyanins. Front. Immunol. 2022 , 13 , 826597. [ Google Scholar ] [ CrossRef ]
• Lei, Z.; Wu, H.; Yang, Y.; Hu, Q.; Lei, Y.; Liu, W.; Nie, Y.; Yang, L.; Zhang, X.; Yang, C.; et al. Ovariectomy Impaired Hepatic Glucose and Lipid Homeostasis and Altered the Gut Microbiota in Mice with Different Diets. Front. Endocrinol. 2021 , 12 , 708838. [ Google Scholar ] [ CrossRef ]
• Di Giorgio, E.; Clocchiatti, A.; Piccinin, S.; Sgorbissa, A.; Viviani, G.; Peruzzo, P.; Romeo, S.; Rossi, S.; Dei Tos, A.P.; Maestro, R.; et al. MEF2 is a converging hub for histone deacetylase 4 and phosphatidylinositol 3-kinase/Akt-induced transformation. Mol. Cell. Biol. 2013 , 33 , 4473–4491. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Douglas, G.M.; Maffei, V.J.; Zaneveld, J.R.; Yurgel, S.N.; Brown, J.R.; Taylor, C.M.; Huttenhower, C.; Langille, M.G.I. PICRUSt2 for prediction of metagenome functions. Nat. Biotechnol. 2020 , 38 , 685–688. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Giallongo, F.; Hristov, A.N.; Oh, J.; Frederick, T.; Weeks, H.; Werner, J.; Lapierre, H.; Patton, R.A.; Gehman, A.; Parys, C. Effects of slow-release urea and rumen-protected methionine and histidine on performance of dairy cows. J. Dairy Sci. 2015 , 98 , 3292–3308. [ Google Scholar ] [ CrossRef ]
• Chen, Q.; Wu, C.; Yao, Z.; Cai, L.; Ni, Y.; Mao, S.; Zhao, R. Whole transcriptome analysis of RNA expression profiles reveals the potential regulating action of long noncoding RNA in lactating cows fed a high concentrate diet. Anim. Nutr. 2021 , 7 , 1315–1328. [ Google Scholar ] [ CrossRef ]
• Kim, Y.H.; Nagata, R.; Ohtani, N.; Ichijo, T.; Ikuta, K.; Sato, S. Effects of Dietary Forage and Calf Starter Diet on Ruminal pH and Bacteria in Holstein Calves during Weaning Transition. Front. Microbiol. 2016 , 7 , 1575. [ Google Scholar ] [ CrossRef ]
• Auffret, M.D.; Dewhurst, R.J.; Duthie, C.A.; Rooke, J.A.; John Wallace, R.; Freeman, T.C.; Stewart, R.; Watson, M.; Roehe, R. The rumen microbiome as a reservoir of antimicrobial resistance and pathogenicity genes is directly affected by diet in beef cattle. Microbiome 2017 , 5 , 159. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Harthan, L.B.; Cherney, D.J.R. Okara as a protein supplement affects feed intake and milk composition of ewes and growth performance of lambs. Anim. Nutr. 2017 , 3 , 171–174. [ Google Scholar ] [ CrossRef ]
• Ben Meir, Y.A.; Nikbachat, M.; Portnik, Y.; Jacoby, S.; Adin, G.; Moallem, U.; Halachmi, I.; Miron, J.; Mabjeesh, S.J. Effect of forage-to-concentrate ratio on production efficiency of low-efficient high-yielding lactating cows. Anim. Int. J. Anim. Biosci. 2021 , 15 , 100012. [ Google Scholar ] [ CrossRef ]
• Cui, Q.; Lin, L.; Lai, Z.; Mao, S. Effects of high-grain diet feeding on fatty acid profiles in milk, blood, muscle, and adipose tissue, and transcriptional expression of lipid-related genes in muscle and adipose tissue of dairy cows. J. Anim. Sci. Biotechnol. 2023 , 14 , 41. [ Google Scholar ] [ CrossRef ]
• Yang, Y.; Ferreira, G.; Teets, C.L.; Corl, B.A.; Thomason, W.E.; Griffey, C.A. Effects of feeding hulled and hull-less barley with low-and high-forage diets on lactation performance, nutrient digestibility, and milk fatty acid composition of lactating dairy cows. J. Dairy Sci. 2018 , 101 , 3036–3043. [ Google Scholar ] [ CrossRef ]
• O’Callaghan, T.F.; Vázquez-Fresno, R.; Serra-Cayuela, A.; Dong, E.; Mandal, R.; Hennessy, D.; McAuliffe, S.; Dillon, P.; Wishart, D.S.; Stanton, C.; et al. Pasture Feeding Changes the Bovine Rumen and Milk Metabolome. Metabolites 2018 , 8 , 27. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Hu, X.; Li, S.; Mu, R.; Guo, J.; Zhao, C.; Cao, Y.; Zhang, N.; Fu, Y. The Rumen Microbiota Contributes to the Development of Mastitis in Dairy Cows. Microbiol. Spectr. 2022 , 10 , e0251221. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Bach, A.; Baudon, M.; Elcoso, G.; Viejo, J.; Courillon, A. Effects on rumen pH and feed intake of a dietary concentrate challenge in cows fed rations containing pH modulators with different neutralizing capacity. J. Dairy Sci. 2023 , 106 , 4580–4598. [ Google Scholar ] [ CrossRef ]
• Zhang, F.; Wang, Y.; Wang, H.; Nan, X.; Guo, Y.; Xiong, B. Calcium Propionate Supplementation Has Minor Effects on Major Ruminal Bacterial Community Composition of Early Lactation Dairy Cows. Front. Microbiol. 2022 , 13 , 847488. [ Google Scholar ] [ CrossRef ]
• Wang, L.; Zhang, G.; Li, Y.; Zhang, Y. Effects of High Forage/Concentrate Diet on Volatile Fatty Acid Production and the Microorganisms Involved in VFA Production in Cow Rumen. Anim. Open Access J. 2020 , 10 , 223. [ Google Scholar ] [ CrossRef ]
• Aschenbach, J.R.; Penner, G.B.; Stumpff, F.; Gabel, G. Ruminant nutrition symposium: Role of fermentation acid absorption in the regulation of ruminal pH. J. Anim. Sci. 2011 , 89 , 1092–1107. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Li, M.; Zhou, M.; Adamowicz, E.; Basarab, J.A.; Guan, L.L. Characterization of bovine ruminal epithelial bacterial communities using 16S rRNA sequencing, PCR-DGGE, and qRT-PCR analysis. Vet. Microbiol. 2012 , 155 , 72–80. [ Google Scholar ] [ CrossRef ]
• Steele, M.A.; Vandervoort, G.; AlZahal, O.; Hook, S.E.; Matthews, J.C.; McBride, B.W. Rumen epithelial adaptation to high-grain diets involves the coordinated regulation of genes involved in cholesterol homeostasis. Physiol. Genom. 2011 , 43 , 308–316. [ Google Scholar ] [ CrossRef ]
• Zhou, M.; Hernandez-Sanabria, E.; Guan, L.L. Characterization of variation in rumen methanogenic communities under different dietary and host feed efficiency conditions, as determined by PCR-denaturing gradient gel electrophoresis analysis. Appl. Environ. Microbiol. 2010 , 76 , 3776–3786. [ Google Scholar ] [ CrossRef ]
• Plaizier, J.C.; Mulligan, F.J.; Neville, E.W.; Guan, L.L.; Steele, M.A.; Penner, G.B. Invited review: Effect of subacute ruminal acidosis on gut health of dairy cows. J. Dairy Sci. 2022 , 105 , 7141–7160. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Guo, Y.; Xiao, L.; Jin, L.; Yan, S.; Niu, D.; Yang, W. Effect of commercial slow-release urea product on in vitro rumen fermentation and ruminal microbial community using RUSITEC technique. J. Anim. Sci. Biotechnol. 2022 , 13 , 56. [ Google Scholar ] [ CrossRef ]
• Li, F.; Feng, Y.; Liu, H.; Kong, D.; Hsueh, C.Y.; Shi, X.; Wu, Q.; Li, W.; Wang, J.; Zhang, Y.; et al. Gut Microbiome and Metabolome Changes in Mice with Acute Vestibular Deficit. Front. Cell. Infect. Microbiol. 2022 , 12 , 821780. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Ma, S.; Qin, J.; Hao, Y.; Fu, L. Association of gut microbiota composition and function with an aged rat model of senile osteoporosis using 16S rRNA and metagenomic sequencing analysis. Aging 2020 , 12 , 10795–10808. [ Google Scholar ] [ CrossRef ] [ PubMed ]
• Liu, Z.; Wang, K.; Nan, X.; Cai, M.; Yang, L.; Xiong, B.; Zhao, Y. Synergistic Effects of 3-Nitrooxypropanol with Fumarate in the Regulation of Propionate Formation and Methanogenesis in Dairy Cows In Vitro. Appl. Environ. Microbiol. 2022 , 88 , e0190821. [ Google Scholar ] [ CrossRef ]
• Wang, Y.; Xia, H.; Yang, Q.; Yang, D.; Liu, S.; Cui, Z. Evaluating Starter Feeding on Ruminal Function in Yak Calves: Combined 16S rRNA Sequencing and Metabolomics. Front. Microbiol. 2022 , 13 , 821613. [ Google Scholar ] [ CrossRef ]
• Lamendella, R.; Domingo, J.W.; Ghosh, S.; Martinson, J.; Oerther, D.B. Comparative fecal metagenomics unveils unique functional capacity of the swine gut. BMC Microbiol. 2011 , 11 , 103. [ Google Scholar ] [ CrossRef ]
• Khafipour, E.; Li, S.; Plaizier, J.C.; Krause, D.O. Rumen microbiome composition determined using two nutritional models of subacute ruminal acidosis. Appl. Environ. Microbiol. 2009 , 75 , 7115–7124. [ Google Scholar ] [ CrossRef ]
• Christensen, L.; Vuholm, S.; Roager, H.M.; Nielsen, D.S.; Krych, L.; Kristensen, M.; Astrup, A.; Hjorth, M.F. Prevotella Abundance Predicts Weight Loss Success in Healthy, Overweight Adults Consuming a Whole-Grain Diet Ad Libitum: A Post Hoc Analysis of a 6-Wk Randomized Controlled Trial. J. Nutr. 2019 , 149 , 2174–2181. [ Google Scholar ] [ CrossRef ]
• Pal, D.; Naskar, M.; Bera, A.; Mukhopadhyay, B. Chemical synthesis of the pentasaccharide repeating unit of the O-specific polysaccharide from Ruminococcus gnavus. Carbohydr. Res. 2021 , 507 , 108384. [ Google Scholar ] [ CrossRef ]

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Wang, K.; Song, D.; Zhang, X.; Datsomor, O.; Jiang, M.; Zhao, G. Effects of High-Grain Diet on Performance, Ruminal Fermentation, and Rumen Microbial Flora of Lactating Holstein Dairy Cows. Animals 2024 , 14 , 2522. https://doi.org/10.3390/ani14172522

Wang K, Song D, Zhang X, Datsomor O, Jiang M, Zhao G. Effects of High-Grain Diet on Performance, Ruminal Fermentation, and Rumen Microbial Flora of Lactating Holstein Dairy Cows. Animals . 2024; 14(17):2522. https://doi.org/10.3390/ani14172522

Wang, Kexin, Damin Song, Xuelei Zhang, Osmond Datsomor, Maocheng Jiang, and Guoqi Zhao. 2024. "Effects of High-Grain Diet on Performance, Ruminal Fermentation, and Rumen Microbial Flora of Lactating Holstein Dairy Cows" Animals 14, no. 17: 2522. https://doi.org/10.3390/ani14172522

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