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  • richardmitnick 12:37 pm on November 29, 2016 Permalink | Reply
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    From Don Lincoln at FNAL: Higgs Boson 2016 Video 

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    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    FNAL Don Lincoln
    From Don Lincoln of FNAL

    Published on Nov 16, 2016

    CERN CMS Higgs Event
    CERN CMS Higgs Event

    The Higgs boson burst into the public arena on July 4, 2012, when scientists working at the CERN laboratory announced the particle’s discovery. However the initial discovery was a bit tentative, with the need to verify that the discovered particle was, indeed, the Higgs boson. In this video, Fermilab’s Dr. Don Lincoln looks at the data from the perspective of 2016 and shows that more recent analyses further supports the idea that the Higgs boson is what was discovered.

    Watch, enjoy, learn.

    The data presented in this video can be seen in a technical form in this paper: http://cds.cern.ch/record/2158863/fil…. Figure 19 is a more accurate version.

    See the full article here .

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    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 3:23 pm on November 12, 2016 Permalink | Reply
    Tags: , Accelerator Science: Circular vs. Linear, Don Lincoln,   

    From Don Lincoln at FNAL: “Accelerator Science: Circular vs. Linear “ 

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    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.
    Nov 10, 2016

    FNAL Don Lincoln
    Don Lincoln

    Particle accelerator are scientific instruments that allow scientists to collide particles together at incredible energies to study the secrets of the universe. However, there are many manners in which particle accelerators can be constructed. In this video, Fermilab’s Dr. Don Lincoln explains the pros and cons of circular and linear accelerators.

    See the full article here .

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 8:00 am on October 8, 2016 Permalink | Reply
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    From Don Lincoln at FNAL: “Eight is enough” 

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    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    October 7, 2016

    FNAL Don Lincoln
    Don Lincoln

    1
    In the search for new physics, no stone can be left unturned. In this analysis, scientists looked for a new particle that underwent a cascade of decays, resulting in eight distinct particles. No image credit.

    While the LHC was built for many purposes, one of the key reasons it was created was to investigate the most energetic collisions possible. The basic idea is that high-energy collisions have the best chance of unveiling phenomena never before observed.

    In particle physics, low-energy things happen all the time, while high-energy things are extremely rare. To give a sense of scale, the lowest-energy collisions that we study occur about a billion times more often than the highest-energy collisions we can create.

    Now if you want to study very high-energy things, you want to use the strongest force available to you. That’s because a strong force makes many collisions, and if you make many collisions, you are more likely to see the rare and very high-energy type of event you are looking for. In particle physics terminology, that means that you need to use events that use the strong nuclear force.

    That works out as a good strategy at the LHC because the LHC collides protons together, and protons are full of quarks and gluons, both of which interact via the strong force. The basic idea is that a quark or gluon from one proton will interact with a quark or gluon from the other proton, merge into some new and undiscovered particle, and then decay and be observed in the detector. Now the CMS experiment has already looked into the case where this new particle decayed directly into two ordinary particles.

    CERN/CMS Detector
    CERN/CMS Detector

    It has also looked into the case where the new particle decayed into two new (but different) particles that then each decayed into two ordinary particles. In this scenario, there would be four ordinary particles hitting the detector. Neither of these analyses led to the discovery of new physics.

    However, there is no reason that these should be the only two possible scenarios. It could be that LHC collisions would make one new particle, which then decayed into two new but lower-mass particles, each of which subsequently decayed into two more new and even lighter particles, resulting in four, which each finally decayed into two ordinary particles, producing eight. Thus the CMS experiment went looking for events in which eight ordinary particles simultaneously hit the detector.

    CMS was searching for particles called “jets,” which are actually collections of even more particles, but we can use algorithms to reduce a jet to looking like a single particle. So they were looking for events that produced eight jets.

    So far so good. The problem with this analysis arises because, even without new physics, the strong nuclear force makes lots of events in which there are eight or more jets, so it is pretty hard to identify events with eight jets that are made by new physics. But there is one saving grace. The collisions in which eight jets are made by ordinary physics have the same basic distribution of total energy as the ones in which only two jets are made. So they use the well-understood two-jet data to make predictions of eight-jet data and then compare it to the measurements all eight-jet data. If too many eight-jet events are found, then maybe they’ve made a discovery.

    Sadly, no excess was found. But this was a clever technique and one that might well be worth pursuing in the future. The most recent paper was for data recorded at a collision energy of eight trillion electronvolts of energy (back in 2012), and we’ve recorded data with 13 trillion electronvolts. Maybe with the new data, this technique will lead to a different result.

    See the full article here .

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 10:39 am on September 20, 2016 Permalink | Reply
    Tags: , Don Lincoln, , , Luminosity vs. Energy, ,   

    From Don Lincoln at FNAL- “Accelerator Science: Luminosity vs. Energy” 

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    FNAL Art Image by Angela Gonzales

    Sep 19, 2016

    FNAL Don Lincoln
    Don Lincoln

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    In the world of high energy physics there are several parameters that are important when one constructs a particle accelerator. Two crucial ones are the energy of the beam and the luminosity, which is another word for the number of particles in the beam. In this video, Fermilab’s Dr. Don Lincoln explains the differences and the pros and cons. He even works in an unexpected sporting event.

    Watch, enjoy, learn.

    See the full article here .

    Please help promote STEM in your local schools.

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 10:02 am on September 8, 2016 Permalink | Reply
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    From Don Lincoln for CNN: “Something is wrong with dark matter” 

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    CNN

    September 7, 2016

    FNAL Don Lincoln
    Don Lincoln

    Dr. Don Lincoln is a senior physicist at Fermilab and does research using the Large Hadron Collider. He has written numerous books and produces a series of science education videos. He is the author of The Large Hadron Collider: The Extraordinary Story of the Higgs Boson and Other Things That Will Blow Your Mind. Follow him on Facebook. The opinions expressed in this commentary are solely those of the author.

    Nearly a mile under the Black Hills of South Dakota sits a canister of the atomic element xenon, chilled cold enough to turn it to liquid. The canister is the Large Underground Xenon, or LUX, detector — the most sensitive dark matter detector in the world.

    SURF logo
    Sanford Underground levels
    Sanford Underground Research Facility
    LUX Dark matter Experiment at SURF
    LUX Dark matter Experiment at SURF

    But the results of a new analysis by the LUX Collaboration has left scientists perplexed about a substance that has guided the formation of the stars and galaxies since the cosmos began: dark matter.

    Since the 1930s, scientists have known that there was something unexplained about the heavens. Swiss astronomer Fritz Zwicky studied the Coma Cluster, a group of about a thousand galaxies, held together by their mutual gravitational interactions.

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    A map of the Coma cluster. http://www.atlasoftheuniverse.com

    There was only one problem: The galaxies were moving so fast that gravity shouldn’t have been able to hold them together. The cluster should have been ripped apart. In the 1970s, astronomers Vera Rubin and her collaborator Kenneth Ford studied the rotation rates of individual galaxies and came to the same conclusion. There appeared to be no way the observed matter contained in galaxies would generate enough gravity to keep the stars locked in their stately orbits.

    These observations, combined with many other independent lines of evidence, led scientists to consider several possible explanations. These explanations included the possibility that Newton’s familiar laws of motion might be wrong, or that our understanding of gravity needed to be modified. Both these proposals, though, have been largely ruled out.

    Another idea was that there was somehow invisible matter that was generating more gravity. Initial ideas centered on the possibility of black holes, brown dwarf stars or rogue planets roaming the cosmos, but those explanations have also been dismissed. Using a ruthless process of elimination worthy of Sherlock Holmes, astronomers have come to believe the explanation for all of the gravitational anomalies is that there must be some sort of new and undiscovered type of matter in the universe, which Zwicky in 1933 named “dunkle materie,” or dark matter.

    For decades, scientists have tried to work out the properties of dark matter and, while we don’t know everything, we know a lot. From astronomical observations, we know there is five times more dark matter in the universe than all the “billions and billions” of stars and galaxies mentioned in Carl Sagan’s oft-quoted phrase. We also know that dark matter cannot have electrical charge, otherwise it would interact with light and we would have seen it. In fact, by a process of elimination, we know that dark matter is not any known form of matter. It is something new. Of this, scientists are sure.

    However, scientists are less sure about the details.

    For decades now, the most popular theoretical idea was that dark matter was a WIMP, short for weakly interacting massive particle. A WIMP would have a mass in the range of 10 to perhaps 100 times heavier than the familiar proton. It was a particle like a heavy neutron (but definitely not a neutron), massive, electrically neutral, and stable on time scales long compared to the lifetime of the universe.
    The WIMP was popular for two main reasons.

    First, when cosmologists modeled the Big Bang and included WIMPs in the calculation, the WIMPs actively participated in the earliest phases of the birth of the universe but, as the universe expanded and cooled, the space between them grew large enough that they stopped interacting with one another. When scientists calculated how much mass should be tied up in the relic WIMPs, they found it was five times as much mass as ordinary matter, exactly the amount of dark matter seen by astronomers.

    The second reason for the popularity of the WIMP idea is that it explained a mystery in particle physics. The recently discovered Higgs boson has a mass of about 130 times that of the proton. Theoretical considerations predicted a much larger mass, but if a WIMP exists, it is easy to reconcile the prediction and measurement. These two reasons account for the popularity of the WIMP idea and are called “the WIMP miracle.”

    The LUX measurement is simply the most recent and most powerful of a long line of searches for dark matter. They found no evidence for the existence of dark matter and were able to rule out a significant range of possible WIMP properties and masses.

    Now this doesn’t mean the WIMP idea is dead or that dark matter has been disproven. There remain WIMP masses that haven’t been ruled out, and there exist other possible dark matter candidates, including objects called sterile neutrinos, which are possible cousins of the well-known neutrinos generated in nuclear reactors and in the sun. Another recurring proposed dark matter particle is the axion, suggested in the 1970s to explain mysteries in the asymmetry of subatomic processes. (Although neither sterile neutrinos, nor axions, have been observed).

    Nobody knows what the final answer will be. That’s why we do research. But there is no question that there is a mystery in the cosmos. Galaxies don’t act as we expect. The LUX measurement is a powerful new bit of information for astronomers to consider and has added to the general confusion, forcing scientists to take another look at ideas other than WIMPs.

    All this reminds me of the old Buffalo Springfield song: “There’s something happening here. What it is ain’t exactly clear …”

    See the full article here .

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  • richardmitnick 2:27 pm on August 25, 2016 Permalink | Reply
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    From Don Lincoln via CNN: “A new planet in our neighborhood — how likely is life?” 

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    CNN

    August 24, 2016

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    Dr. Don Lincoln is a senior physicist at Fermilab and does research using the Large Hadron Collider. He has written numerous books and produces a series of science education videos. He is the author of Alien Universe: Extraterrestrial Life in Our Minds and in the Cosmos. Follow him on Facebook. The opinions expressed in this commentary are solely those of the author.

    Space. The final frontier.

    These words inspired many young people to enter science (including me), but I’ll bet that’s especially true for the team who announced Wednesday that they had found evidence of an Earth-like planet orbiting Proxima Centauri, our closest star. This planet is tentatively called Proxima b.

    Pale Red Dot
    Pale Red Dot project at ESO

    Scientists working at the European Southern Observatory (ESO), using the La Silla telescope, claim to have discovered the closest exoplanet to Earth.

    ESO 3.6m telescope & HARPS at LaSilla
    ESO 3.6m telescope & HARPS at LaSilla, Chile

    Exoplanet, of course, means planets orbiting stars other than the Sun. Over 3,000 exoplanets have been discovered by facilities like the ESO and the Kepler orbiting observatory. Most of them are huge planets orbiting very near their star — Jupiter-like planets heated to temperatures guaranteed to sterilize them of life as we know it.

    In recent years, instrumentation has improved to the point that not only can individual planets be found, but even complete solar systems, consisting of many planets. This has been a heady time for planet hunters.

    The goal of those inspired by Star Trek’s opening words has not been to find planets, but to find planets that are like Earth — meaning at a temperature on which liquid water could be present and which could theoretically support some form of life. This is what astronomers call “the habitable zone.” In addition, we’d like to find a planet that is nearby.

    After all, space is huge and human spacecraft using current technology would take tens of thousands of years to get to even this, our closest celestial neighbor. To give a sense of scale, that’s longer than human civilization has existed. There are plans under discussion that might reduce travel time to a more manageable duration, even less than a single human lifespan.

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    Related article: Proxima b: Closest rocky planet to our solar system found

    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker
    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker

    So what might this newly discovered planet look like? Well, even though its temperature is thought to be such that liquid water could exist, you shouldn’t imagine a lush and verdant world, with lovely blue waters, sandy beaches, lush and green plants, with an excited alien fish occasionally breaching the waters. There are lots of reasons why these are unreasonable expectations.

    Setting aside the possibility of life for a moment, Proxima Centauri is a red dwarf, which is the most common type of star in the galaxy. Red dwarfs are much smaller than our Sun. For instance, Proxima Centauri is only about 1.5 times larger than Jupiter. Red dwarfs are very dim. For instance, in the visible spectrum that we use to see, Proxima Centauri gives off 0.0056% as much as light as the Sun.

    Most of the light given off by Proxima Centauri is in the infrared region, but even if you compare all of the light emitted by Proxima Centauri in all wavelengths to the amount emitted by the Sun, Proxima Centauri still emits only 0.17% as much light as our own life-giving stellar companion. The star also emits as much x-rays as our own Sun, but Proxima b is much closer to its stellar parent, so the surface receives far more x-rays than Earth.

    In addition to being a very dim star, Proxima Centauri is known to be a “flare star,” which means the star periodically gives off far more light than usual. During these flares, the x-ray emission can go up tenfold.

    Because of the star’s small size, a planet in the habitable zone will have to be in a very small orbit, taking under two weeks to complete a single orbit. Any planet that close to a star will be “tidally locked,” which means that one face of the planet will constantly face the star. This is just like the Earth and Moon, where we see only one side of the Moon throughout the course of the Month. Proxima Centauri’s planetary companion will likely have one side in perpetual daylight, while the other is in perpetual night.

    So what about life? Are there any chances that an alien lizard might bask in Proxima Centauri’s light or try to find shade under an alien tree? Well, given the instability of the light emitted by the parent star, the answer is likely no, although the real answer to that question is obviously something for observations to answer.

    Given the very dim light output of the star, it is likely that any hypothetical plants would have to be black, as black is the most light-absorbent color. “Sunlight” would be precious and evolution would drive alien plants to find ways to collect every bit of energy that falls on them.

    Realistically, the prospect of life is improbable. This planet is unlikely to be a haven for people trying to escape the ecological issues of Earth, so we should not view this discovery as a way to ignore our own ecosystem.

    Still, the question of extraterrestrial life is a fascinating one, so astronomers are devising techniques to look at the planet’s atmosphere. Certain chemicals, like oxygen or methane, cannot exist long in a planet’s atmosphere without being constantly replenished by living organisms. Observing them would be strong evidence for life.

    So, what’s the bottom line? First, the discovery, if confirmed is extremely exciting. The existence of a nearby planet in the habitable zone will perhaps increase the interest in efforts like Project Starshot, which aims to send microprobes to Proxima Centauri with a transit time of about twenty years. It may well be that this discovery will excite an entirely new generation of the prospect “to boldly go where no one has gone before.”

    See the full article here .

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  • richardmitnick 10:32 am on July 25, 2016 Permalink | Reply
    Tags: , Don Lincoln, , , Possible fifth force?,   

    From Don Lincoln of FNAL on livescience: “A Fifth Force: Fact or Fiction” 

    Livescience

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    FNAL

    FNAL Don Lincoln
    Don lincoln

    July 5, 2016

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    Has a Hungarian lab really found evidence of a fifth force of nature? Credit: Jurik Peter / Shutterstock.com

    Science and the internet have an uneasy relationship: Science tends to move forward through a careful and tedious evaluation of data and theory, and the process can take years to complete. In contrast, the internet community generally has the attention span of Dory, the absent-minded fish of Finding Nemo(and now Finding Dory) — a meme here, a celebrity picture there — oh, look … a funny cat video.

    Thus people who are interested in serious science should be extremely cautious when they read an online story that purports to be a paradigm-shifting scientific discovery. A recent example is one suggesting that a new force of nature might have been discovered. If true, that would mean that we have to rewrite the textbooks.

    A fifth force

    So what has been claimed?

    In an article submitted on April 7, 2015, to the arXiv repository of physics papers, a group of Hungarian researchers reported on a study in which they focused an intense beam of protons (particles found in the center of atoms) on thin lithium targets. The collisions created excited nuclei of beryllium-8, which decayed into ordinary beryllium-8 and pairs of electron-positron particles. (The positron is the antimatter equivalent of the electron.)

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    The Standard Model is the collection of theories that describe the smallest experimentally observed particles of matter and the interactions between energy and matter. Credit: Karl Tate, LiveScience Infographic Artist

    They claimed that their data could not be explained by known physical phenomena in the Standard Model, the reigning model governing particle physics. But, they purported, they could explain the data if a new particle existed with a mass of approximately 17 million electron volts, which is 32.7 times heavier than an electron and just shy of 2 percent the mass of a proton. The particles that emerge at this energy range, which is relatively low by modern standards, have been well studied. And so it would be very surprising if a new particle were discovered in this energy regime.

    However, the measurement survived peer review and was published on Jan. 26, 2016, in the journal Physical Review Letters, which is one of the most prestigious physics journals in the world. In this publication, the researchers, and this research, cleared an impressive hurdle.

    Their measurement received little attention until a group of theoretical physicists from the University of California, Irvine (UCI), turned their attention to it. As theorists commonly do with a controversial physics measurement, the team compared it with the body of work that has been assembled over the last century or so, to see if the new data are consistent or inconsistent with the existing body of knowledge. In this case, they looked at about a dozen published studies.

    What they found is that though the measurement didn’t conflict with any past studies, it seemed to be something never before observed — and something that couldn’t be explained by the Standard Model.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.
    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth

    New theoretical framework

    To make sense of the Hungarian measurement, then, this group of UCI theorists invented a new theory.

    The theory invented by the Irvine group is really quite exotic. They start with the very reasonable premise that the possible new particle is something that is not described by existing theory. This makes sense because the possible new particle is very low mass and would have been discovered before if it were governed by known physics. If this were a new particle governed by new physics, perhaps a new force is involved. Since traditionally physicists speak of four known fundamental forces (gravity, electromagnetism and the strong and weak nuclear forces), this hypothetical new force has been dubbed “the fifth force.”

    Theories and discoveries of a fifth force have a checkered history, going back decades, with measurements and ideas arising and disappearing with new data. On the other hand, there are mysteries not explained by ordinary physics like, for example, dark matter. While dark matter has historically been modeled as a single form of a stable and massive particle that experiences gravity and none of the other known forces, there is no reason that dark matter couldn’t experience forces that ordinary matter doesn’t experience. After all, ordinary matter experiences forces that dark matter doesn’t, so the hypothesis isn’t so silly.

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    There is no reason dark matter couldn’t experience forces that ordinary matter doesn’t experience. Here, in the galaxy cluster Abell 3827, dark matter was observed interacting with itself during a galaxy collision. Credit: ESO

    There are many ideas about forces that affect only dark matter and the term for this basic idea is called “complex dark matter.” One common idea is that there is a dark photon that interacts with a dark charge carried only by dark matter. This particle is a dark matter analog of the photon of ordinary matter that interacts with familiar electrical charge, with one exception: Some theories of complex dark matter imbue dark photons with mass, in stark contrast with ordinary photons.

    If dark photons exist, they can couple with ordinary matter (and ordinary photons) and decay into electron-positron pairs, which is what the Hungarian research group was investigating. Because dark photons don’t interact with ordinary electric charge, this coupling can only occur because of the vagaries of quantum mechanics. But if scientists started seeing an increase in electron-positron pairs, that might mean they were observing a dark photon.

    The Irvine group found a model that included a “protophobic” particle that was not ruled out by earlier measurements and would explain the Hungarian result. Particles that are “protophobic,” which literally means “fear of protons,” rarely or never interact with protons but can interact with neutrons (neutrophilic).

    The particle proposed by the Irvine group experiences a fifth and unknown force, which is in the range of 12 femtometers, or about 12 times bigger than a proton. The particle is protophobic and neutrophilic. The proposed particle has a mass of 17 million electron volts and can decay into electron-positron pairs. In addition to explaining the Hungarian measurement, such a particle would help explain some discrepancies seen by other experiments. This last consequence adds some weight to the idea.

    Paradigm-shifting force?

    So this is the status.

    What is likely to be true? Obviously, data is king. Other experiments will need to confirm or refute the measurement. Nothing else really matters. But that will take a year or so and having some idea before then might be nice. The best way to estimate the likelihood the finding is real is to look at the reputations of the various researchers involved. This is clearly a shoddy way to do science, but it will help shade your expectations.

    So let’s start with the Irvine group. Many of them (the senior ones, typically) are well- regarded and established members of the field, with substantive and solid papers in their past. The group includes a spectrum of ages, with both senior and junior members. In the interest of full disclosure, I know some of them personally and, indeed, two of them have read the theoretical portions of chapters of books I have written for the public to ensure that I didn’t say anything stupid. (By the way, they didn’t find any gaffes, but they certainly helped clarify certain points.) That certainly demonstrates my high regard for members of the Irvine group, but possibly taints my opinion. In my judgment, they almost certainly did a thorough and professional job of comparing their new model to existing data. They have found a small and unexplored region of possible theories that could exist.

    On the other hand, the theory is pretty speculative and highly improbable. This isn’t an indictment … all proposed theories could be labeled in this way. After all, the Standard Model, which governs particle physics, is nearly a half century old and has been thoroughly explored. In addition, ALL new theoretical ideas are speculative and improbable and almost all of them are wrong. This also isn’t an indictment. There are many ways to add possible modifications to existing theories to account for new phenomena. They can’t all be right. Sometimes none of the proposed ideas are right.

    However, we can conclude from the reputation of the group’s members that they have generated a new idea and have compared it to all relevant existing data. The fact that they released their model means that it survived their tests and thus it remains a credible, if improbable, possibility.

    What about the Hungarian group? I know none of them personally, but the article was published in Physical Review Letters — a chalk mark in the win column. However, the group has also published two previous papers in which comparable anomalies were observed, including a possible particle with a mass of 12 million electron volts and a second publication claiming the discovery of a particle with a mass of about 14 million electron volts. Both of these claims were subsequently falsified by other experiments.

    Further, the Hungarian group has never satisfactorily disclosed what error was made that resulted in these erroneous claims. Another possible red flag is that the group rarely publishes data that doesn’t claim anomalies. That is improbable. In my own research career, most publications were confirmation of existing theories. Anomalies that persist are very, very, rare.

    So what’s the bottom line? Should you be excited about this new possible discovery? Well…sure…possible discoveries are always exciting. The Standard Model has stood the test of time for half a century, but there are unexplained mysteries and the scientific community is always looking for the discovery that points us in the direction of a new and improved theory. But what are the odds that this measurement and theory will lead to the scientific world accepting a new force with a range of 12 fm and with a particle that shuns protons? My sense is that this a long shot. I am not so sanguine as to the chances of this outcome.

    Of course, this opinion is only that…an opinion, albeit an informed one. Other experiments will also be looking for dark photons because, even if the Hungarian measurement doesn’t stand up to scrutiny, there is still a real problem with dark matter. Many experiments looking for dark photons will explore the same parameter space (e.g. energy, mass and decay modes) in which the Hungarian researchers claim to have found an anomaly. We will soon (within a year) know if this anomaly is a discovery or just another bump in the data that temporarily excited the community, only to be discarded as better data is recorded. And, no matter the outcome, good and better science will be the eventual result.

    See the full article here .

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  • richardmitnick 3:40 pm on July 6, 2016 Permalink | Reply
    Tags: , Don Lincoln, , , Quantum Color   

    From Don Lincoln at FNAL: “Quantum Color” 

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    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    From Don Lincoln, Fermilab

    FNAL Don Lincoln
    Don Loncoln

    Published on Jun 17, 2016 [Just made it to social media]

    The strongest force in the universe is the strong nuclear force and it governs the behavior of quarks and gluons inside protons and neutrons. The name of the theory that governs this force is quantum chromodynamics, or QCD. In this video, Fermilab’s Dr. Don Lincoln explains the intricacies of this dominant component of the Standard Model.

    Watch, enjoy learn.

    See the full article here .

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    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 5:57 pm on June 20, 2016 Permalink | Reply
    Tags: , Don Lincoln, , , QCD: Quantum Chromodynamics   

    From Don Lincoln at FNAL: “QCD: Quantum Chromodynamics” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    FNAL Don Lincoln
    Don Lincoln

    The strongest force in the universe is the strong nuclear force and it governs the behavior of quarks and gluons inside protons and neutrons. The name of the theory that governs this force is quantum chromodynamics, or QCD. In this video, Fermilab’s Dr. Don Lincoln explains the intricacies of this dominant component of the Standard Model.

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    Watch, enjoy, learn.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
  • richardmitnick 5:11 pm on June 17, 2016 Permalink | Reply
    Tags: , , Don Lincoln, , ,   

    From Don Lincoln at FNAL: “The triumphant Standard Model” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    June 17, 2016

    FNAL Don Lincoln
    Don Lincoln

    In high-end research, there are a couple of deeply compelling types of data analyses that scientists do. There are those that break the existing scientific understanding and rewrite the textbooks. Those are exciting. But there are also those in which a highly successful theory is tested in a regime never before explored. There can also be two types of outcome. If the theory fails to explain the data, we have a discovery of the type I mentioned first. But it is also possible that the theory explains the data perfectly well. If so, that means that you’ve proven that the existing theory is even more successful than was originally known. That’s a different kind of success. It means that predictions made in one realm taught scientists enough to understand far more.

    In the LHC, pairs of protons are collided together with the unprecedented energy of 13 trillion electronvolts of energy.

    CERN/LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN

    Before 2015, when the data in this analysis was recorded, the highest energy ever studied by humanity was only 8 trillion electronvolts. So, already we know that the new data is 63 percent higher in terms of energy reach as compared to the old data. To get a visceral sense of what that means, imagine that your bank told you that they made a mistake and that for every dollar you thought you had in your account, you actually had $1.63. I’m guessing you’d start planning for an awesome vacation or perhaps an earlier retirement.

    When the protons collide, most commonly, a quark or gluon from each proton hits a quark or gluon from the other proton and knocks them out of the collision area into the detector. As the quarks and gluons leave the collision area, they convert into sprays of particles that travel in roughly the same direction. These are called jets. Physicists study the location and energy of the jets in the detector and compare them to the predicted distribution.

    CMS scientists studied the production patterns of jets at a collision energy of 13 trillion electronvolts and found that they agreed with the predictions of the Standard Model with the same level of precision seen at lower energy measurements.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.
    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth

    This result comes with a small sadness because this means that new physics hasn’t been discovered. On the other hand, it is a resounding endorsement of the theory of quantum chromodynamics, or QCD, which is the portion of the Standard Model that deals explicitly with quark and gluon scattering. QCD, first worked out nearly half a century ago, continues its decades-long track record of success.

    2
    Scientists are constantly exploring the universe, seeing what happens when existing theories are tested in new realms. In today’s analysis, scientists put the leading theory of quark scattering to the test, studying what happens when it is compared to data taken at energies over 60 percent higher than ever before achieved.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
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