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  • richardmitnick 7:22 am on June 6, 2015 Permalink | Reply
    Tags: , EuroCirCol, , , Particle Physics   

    From CERN- “EuroCirCol: A key to New Physics” This Is Big News 

    CERN New Masthead

    Mon 08 Jun 2015
    Johannes Gutleber

    Monday 1 June saw the start of EuroCirCol, the EC-funded part of the FCC study that will develop the conceptual design for an energy-frontier hadron collider.

    1
    Attendees at the EuroCirCol meeting at CERN.

    The EuroCirCol kick-off event at CERN on 2 to 4 June brought together 62 participants to constitute governance bodies, commit to the project plan and align the organisation, structures and processes of 16 institutions from 10 countries. The goal of the project is to conceive a post-LHC research infrastructure around a 100 km circular energy-frontier hadron collider capable of reaching 100 TeV collisions. The project officially started on 1 June and will run for four years. The total estimated budget of 11.2 MEUR includes a 2.99 MEUR contribution from the Horizon 2020 programme dedicated to the development of new world-class research infrastructures.

    EuroCirCol will deliver a design for a hadron collider as part of the broader Future Circular Collider (FCC) study. It will provide input to an accelerator infrastructure roadmap taking into account European and global interests by the time of the next update of the European Strategy for Particle Physics in 2018. It was the only one of 39 submissions to receive the maximum number of points from reviewers, a clear sign that high-energy physics remains a top priority for the European Commission.

    EuroCirCol is organised around four technical work packages: the first two relate to the development of the collider’s lattice and beam optics, including the experimental regions. A third is for the development of prototypes and will test a novel cryogenic beam vacuum system that can respond to the challenges of the high synchrotron radiation expected at such a collider. This work also pioneers collaboration between the particle physics light source communities, with opportunities to improve existing synchrotron radiation facilities and to reduce the cost and improve performance of fourth- or fifth-generation light sources. The last work package will study a viable design for a 16 Tesla accelerator magnet as part of a worldwide study of conductor R&D for the HL-LHC project and the FCC study.

    The EuroCirCol project creates opportunities for doctoral and post-doctoral assignments in the areas of beam optics and accelerator technologies in the participating institutes. It also provides excellent training opportunities for next-generation accelerator physicists under the guidance of world-renowned experts in the field.

    EuroCirCol is a building block in the globally coordinated strategy of the FCC study to produce a global design for a global machine. The main outcome of EuroCirCol will be the laying of foundations for subsequent research infrastructure development that will strengthen Europe as a leader in global research cooperation over the coming decades.

    See the full article here.

    Please help promote STEM in your local schools.

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    Meet CERN in a variety of places:

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New
    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New

    LHC

    CERN LHC New
    CERN LHC Grand Tunnel

    LHC particles

    Quantum Diaries

     
  • richardmitnick 6:41 am on June 6, 2015 Permalink | Reply
    Tags: , , , , , Particle Physics   

    From ATLAS at CERN’s LHC: “Setting Off To New Energy Horizons” 

    CERN New Masthead

    June 4, 2015
    Andreas Hoecker & Marumi Kado, CERN

    1
    Display of a proton-proton collision event recorded by ATLAS on 3 June 2015, with the first LHC stable beams at a collision energy of 13 TeV. Tracks reconstructed by the tracking detector are shown as light blue lines, and hits in the layers of the silicon tracking detector are shown as colored filled circles. The four inner layers are part of the silicon pixel detector and the four outer layers are part of the silicon strip detector. The layer closest to the beam, called IBL, is new for Run 2. In the view in the bottom right it is seen that this event has multiple pp collisions. The total number of reconstructed collision vertices is 17 but they are not all resolvable on the scale of this picture..

    After a shutdown of more than two years, Run 2 of the Large Hadron Collider (LHC) is restarting at a centre-of-mass energy of 13 TeV for proton–proton collisions and increased luminosity. This new phase will allow the LHC experiments to explore nature and probe the physical laws governing it at scales never reached before.

    In this first long shutdown, during which the LHC was consolidated, the ATLAS experiment saw a flurry of activity ranging from upgrades and repairs of the detector, its electronics and the trigger system, to a reappraisal of the computing and software used for the data reconstruction and analysis. ATLAS physicists have also used the time without beam to finalise and improve their analyses of the Run-1 data. In spite of the small relative amount of data collected, only 1% of the total dataset expected for the entire LHC programme, the data recorded by ATLAS with collision energies up to 8 TeV have provided a wealth of physics results and led to more than four hundred scientific publications.

    The expectations were high for this unique experimental endeavour represented by the LHC and its ultra-sophisticated particle detectors of which ATLAS is the largest one. The tera (1012) electron-Volt energy scale to which the LHC collisions of high-energetic protons are sensitive was sought to reveal new particles or phenomenon related to the mechanism that gives mass to elementary particles. The most anticipated and acclaimed scenario, and key prediction of the Standard Model, was the Brout-Englert-Higgs mechanism that predicted a spin-zero Higgs boson with a mass in reach of the LHC. Such a boson was discovered in 2012 by the ATLAS and CMS experiments successfully culminating decades of experimental and theoretical effort. This discovery, and a plethora of other important results pushing the frontier of our knowledge, made the LHC Run-1 an astounding success.

    2
    Standard Model of Particle Physics. The diagram shows the elementary particles of the Standard Model (the Higgs boson, the three generations of quarks and leptons, and the gauge bosons), including their names, masses, spins, charges, chiralities, and interactions with the strong, weak and electromagnetic forces. It also depicts the crucial role of the Higgs boson in electroweak symmetry breaking, and shows how the properties of the various particles differ in the (high-energy) symmetric phase (top) and the (low-energy) broken-symmetry phase (bottom).

    What’s next? It doesn’t take long, when ambling the corridors along the ATLAS offices at CERN, to realise the suspense that reigns among the physicists running the experiment and preparing the analysis of the first Run-2 collisions. The new data, initially produced at 60% higher collision energy and promising to be several times more abundant than before, have the potential to dramatically extend the results from Run-1. The Higgs boson properties will be measured to much better precision, and new production and decay channels may be observed, further revealing the nature of this particle. Higgs physics will continue to be at the heart of Run-2, but the new data will also allow ATLAS to measure Standard Model processes at unprecedented energies and level of accuracy at hadron colliders, and detect yet unobserved rare processes. High-precision measurements of the masses and couplings of the heaviest known particles, are particularly important as they are indirectly sensitive to new phenomena entering the observed particle reactions through so-called virtual processes.

    These measurements, however, are challenging and will take time to complete. Yet the excitement felt in the ATLAS offices is due to another virtue of the higher collision energy in Run-2: the possibility of directly creating new, heavy particles in the most energetic proton–proton collisions owing to the proportionality relation between energy and mass. There are several reasons to conjecture the existence of such particles. Among these is dark matter, a phenomenon believed to involve physics beyond the Standard Model. Dark matter, if it couples to the known particles, could be produced at the LHC and detected by ATLAS in events with an apparent energy imbalance due to energy taken away by invisible (dark matter) particles. These particles could have any mass and couplings, and we neither know whether the LHC can produce them, nor whether the experiments can detect them, even if they existed. Another motivation for new phenomena beyond the Standard Model lies in an apparent shortcoming of the Higgs mechanism itself. Unlike matter particles, which by virtue of an underlying symmetry appear naturally light with respect to the extremely high energies that are thought to have existed during the earliest moments of the big bang, spin-zero particles such as the Higgs boson in the Standard Model do not have such a protective symmetry. It thus appears unnatural that the Higgs boson is so much lighter than these early energy scales where new phenomena are expected to govern physical laws. A new symmetry, such as the co-called “supersymmetry”, could solve that problem.

    Supersymmetry standard model
    Standard Model of Supersymmetry

    Other mechanisms exist; all have in common to introduce new particles of which some may be observable at the LHC, and these new particles could potentially play the role of dark matter as well. ATLAS physicists will therefore mine the new data to deeply and comprehensively search for new physics. The higher collision energy will help to rapidly surpass the sensitivity of the searches conducted during Run-1.

    Ample opportunities but also significant challenges are facing the experimentalists. Critical attention and patience are required for a precise understanding of the new data before drawing conclusions. ATLAS is ready for it.

    See the full article here.

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    Meet CERN in a variety of places:

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New
    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New

    LHC

    CERN LHC New
    CERN LHC Grand Tunnel

    LHC particles

    Quantum Diaries

     
  • richardmitnick 6:11 am on June 5, 2015 Permalink | Reply
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    From LC Newsline: “Future large colliders in Asia – a personal perspective” 

    Linear Collider Collaboration header
    Linear Collider Collaboration

    28 May 2015
    Prof. Jie Gao, Institute of High Energy Physics, CAS, China

    1
    Qinghuada is the potential site for the Chinese collider.

    With the discovery of the Higgs particle at the Large Hadron Collider at CERN in July 2012, after more than 50 years of searching, particle physics has finally entered the era of the Higgs, and the door for human beings to understand the unknown part of the Universe is wide open!

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

    The Standard Model theory of particle physics is now gloriously complete: all particles that it has predicted have been found through experimental discovery with particle colliders.

    2
    Standard Model of Particle Physics. The diagram shows the elementary particles of the Standard Model (the Higgs boson, the three generations of quarks and leptons, and the gauge bosons), including their names, masses, spins, charges, chiralities, and interactions with the strong, weak and electromagnetic forces. It also depicts the crucial role of the Higgs boson in electroweak symmetry breaking, and shows how the properties of the various particles differ in the (high-energy) symmetric phase (top) and the (low-energy) broken-symmetry phase (bottom).

    Now is the time to nail it down with precision and to match to new theories to cover the unknown components of the Universe, such as Dark Matter and Dark Energy, through Higgs with its field stretched out to the whole Universe space. The Higgs couples not only to known fundamental particles in the Standard Model but might also couple to unknown parts of the Universe. To understand the whole Universe, with 5% of known Standard Model particles, 27% of Dark Matter and 68% Dark Energy, on the basis of the fundamental principles, the key of keys is to understand the 125-GeV Higgs with great precision. In fact, this task has great importance in science in terms of the fundamental understanding the Universe as a whole, including its beginning, its current status and its evolution. It is in this sense that studying the Higgs with great precision becomes one of the top subjects of big science.

    Different from a hundreds years ago, big science requires big instruments, a big scientific community, and big collaborations, especially in particle physics, which is becoming one of the precious cultures in human beings’ scientific activities. Different from a hundreds years ago, big science requires big investment in terms of both finance and human resources. However, just like a hundred years ago, big science rewards human beings in all aspects of life and activities on this planet and in space, such as electricity, nuclear power, and the World Wide Web as a (big!) byproduct out of big science research activity. And who knows, maybe (in at least philosophical point of view) human beings might one day be able to collide Dark Matter with the Higgs to release energy just like what we have done to hit atomic nucleus with neutrons to release nuclear energy.

    Concerning precise Higgs studies and beyond, the International Linear Collider (ILC), baptised by the International Committee of Future Accelerators (ICFA) in 2004, is one of such future big instruments. It is an electron-positron linear collider based on superconducting linear accelerator technology, with a potential of exploring centre-of-mass energies up to 1 TeV. In 2013, the ILC team finished its Technical Design Report (TDR), and Japan is considering to become its hosting country.

    In September 2012, right after the Higgs was found at the LHC, Chinese scientists proposed a circular electron-positron collider in China at 240 GeV centre of mass for Higgs studies with two detectors situated in a very long tunnel at least twice the size of the LHC at CERN. It could later be used to host a proton-proton collider well beyond LHC energy potential to reach a new energy frontier.

    From 12 to 14 June 2013, the 464th Fragrant Hill Meeting was held in Beijing about the strategy of Chinese high energy physics development after Higgs discovery, and the following consensuses were reached: 1) support ILC and participate to ILC construction with in-kind contributions, and request R&D fund from Chinese government; 2) as the next collider after BEPCII in China, a circular electron-positron Higgs factory(CEPC) and a Super proton-proton Collier (SppC) afterwards in the same tunnel is an important option and a historical opportunity, and corresponding R&D is needed.

    BEPII Beijing Electron Positron Collider
    BEPII Beijing Electron Positron Collider interior
    BEPII

    The vision of the 464th Fragrant Hill Meeting consensuses is that firstly, ILC is the right machine to be built globally in the world with its centre- of-mass energy potential up to 1 TeV, and China will be one of its important participants and contributors, and secondly, China should contribute not only through ILC collaboration and participation, but also make contributions to precise Higgs measurement through CEPC jointly with ILC for a period of time as a combined instrument with three detectors taking data during ILC and CEPC operation to ensure the excellent joint precision, and thirdly, shifts from CEPC operation to SppC construction and operation to explore physics in energy frontier as long term contribution.

    In fact, ILC and CEPC are complementary, and the complementarity between ILC and CEPC manifests itself not only through more detectors to increase joint measurement precision, but also through their energy region running scenarios. The ILC and CEPC are planning starting times that are almost the same. The ILC runs only at 500 and 350 GeV in the first five years, while CEPC during this time is running at 240GeV. After 5 to 7 years running, CEPC will start its shift to SppC, while the ILC continues a 20-year programme running at 500GeV, with possible upgrades to 1TeV and beyond.

    Finally, the fact that Japan and China, both Asian countries, having strong willingness to contribute to the high-energy physics community and science in general with world participation, one for hosting ILC and another for CEPC, is really excellent, it responds well to the fact that we have entered the era of the Higgs, and ILC and CEPC are a needed united big instrument to have excellent joint precision for Higgs study and beyond.

    See the full article here.

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    The Linear Collider Collaboration is an organisation that brings the two most likely candidates, the Compact Linear Collider Study (CLIC) and the International Liner Collider (ILC), together under one roof. Headed by former LHC Project Manager Lyn Evans, it strives to coordinate the research and development work that is being done for accelerators and detectors around the world and to take the project linear collider to the next step: a decision that it will be built, and where.

    Some 2000 scientists – particle physicists, accelerator physicists, engineers – are involved in the ILC or in CLIC, and often in both projects. They work on state-of-the-art detector technologies, new acceleration techniques, the civil engineering aspect of building a straight tunnel of at least 30 kilometres in length, a reliable cost estimate and many more aspects that projects of this scale require. The Linear Collider Collaboration ensures that synergies between the two friendly competitors are used to the maximum.

    Linear Collider Colaboration Banner

     
  • richardmitnick 9:05 am on June 4, 2015 Permalink | Reply
    Tags: , , , , , Particle Physics,   

    From DOE via FNAL: “U.S. joins the world in a new era of research at the Large Hadron Collider” 

    FNAL Home

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

    The following news release about the restart of the Large Hadron Collider is being issued by the U.S. Department of Energy’s Fermi National Accelerator Laboratory on behalf of the U.S. scientists working on the LHC. Fermilab serves as the U.S. hub for the CMS experiment at the LHC and the roughly 1,000 U.S. scientists who work on that experiment, including about 100 Fermilab employees. Fermilab is a Tier 1 computing center for LHC data and hosts a Remote Operations Center to process and analyze that data. Read more information about Fermilab’s role in the CMS experiment and the LHC. See a list of Fermilab scientists who can speak about the LHC.

    1
    One of the first collisions in the CMS detector at the record-high energy of 13 TeV, taken during testing for the second run of the Large Hadron Collider in late May. Image: CMS/CERN

    New LHC data gives researchers from around the world their best chance yet to study the Higgs boson and search for dark matter and new particles.

    Today scientists at the Large Hadron Collider at CERN, the European research facility, started recording data from the highest-energy particle collisions ever achieved on Earth.

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

    This new proton collision data, the first recorded since 2012, will enable an international collaboration of researchers that includes more than 1,700 U.S. physicists to study the Higgs boson, search for dark matter and develop a more complete understanding of the laws of nature.

    “Together with collaborators from around the world, scientists from roughly 100 U.S. universities and laboratories are exploring a previously unreachable realm of nature,” said James Siegrist, the U.S. Department of Energy’s associate director of science for high-energy physics. “We are very excited to be part of the international community that is pushing the boundaries of our knowledge of the universe.”

    The Large Hadron Collider, the world’s largest and most powerful particle accelerator, reproduces conditions similar to those that existed immediately after the big bang. In 2012, during the LHC’s first run, scientists discovered the Higgs boson—a fundamental particle that helps explain why certain elementary particles have mass. U.S. scientists represent about 20 percent and 30 percent, respectively, of the ATLAS and CMS collaborations, the two international teams that co-discovered the Higgs boson. Hundreds of U.S. scientists played vital roles in the Higgs discovery and will continue to study its remarkable properties.

    CERN ATLAS New
    ATLAS

    CERN CMS Detector
    CMS

    Scientists will use this new LHC data to pin down properties of the Higgs boson and search for new physics and phenomena such as dark matter particles—an invisible form of matter that makes up 25 percent of the entire mass and energy of the universe. Physicists will also endeavor to answer questions such as: Why is there more matter than antimatter? Why is the Higgs boson so light? Are there additional types of Higgs particles? What did matter look like immediately after the big bang?

    NSF-funded researchers at ATLAS, CMS and LHCb are investigating some of nature’s most fundamental properties at collision energies never before explored.

    CERN LHCb New II
    LHCb

    The potential for transformative discoveries is profound,” said Denise Caldwell, NSF’s division director for physics. “We eagerly look forward to LHC operation at almost twice the energy of any other particle accelerator on Earth.”

    The LHC was turned off in early 2013, and engineers spent two years preparing the machine to collide particles at a much higher energy and intensity. During the shutdown, U.S. scientists and their international collaborators installed several new components in the four LHC detectors. These components, together with other upgrades, will allow physicists to record more information about the particles produced during the high-energy collisions.

    These upgrades included a new detector in the heart of the ATLAS experiment, several new muon detectors on the outer shell of the CMS experiment, a new calorimeter inside the ALICE experiment and an innovative new data sorting system for the LHCb experiment.

    CERN ALICE New II
    ALICE

    U.S. scientists played vital roles in the design and instrumentation of these new systems and will operate several of the detector components throughout the next three years of data collection.

    Once collected at CERN in Geneva, Switzerland, the new LHC data travels the globe. New fiber optic cables recently installed by the U.S. Department of Energy bring the data to computers and data centers at 18 U.S. institutions, which provide 35 percent of the worldwide computing power for the CMS experiment and 23 percent for the ATLAS experiment.

    The upgraded LHC will also generate data at a much faster rate. Scientists predict they will match the amount of data generated throughout the collider’s first three-year run within the next five months, eventually accumulating 10 times more data by the end of 2017. These collisions will also produce Higgs bosons 25 percent faster and will increase the chances of seeing other theoretical particles, such as those predicted for supersymmetry, by over 40 percent.

    “The first three-year run of the LHC, which culminated with major discovery in July 2012, was only the start of our journey. It is time for new physics!” said CERN Director-General Rolf Heuer. “We have seen first data beginning to flow. Let’s see what they will reveal to us about how our universe works.”

    CERN, the European Organization for Nuclear Research, is the world’s leading laboratory for particle physics. It has its headquarters in Geneva. At present, its Member States are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a Candidate for Accession. Serbia is an Associate Member in the pre-stage to Membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Union, JINR and UNESCO have Observer Status.

    The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

    The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2015, its budget is $7.3 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 48,000 competitive proposals for funding and makes about 11,000 new funding awards. NSF also awards about $626 million in professional and service contracts yearly.

    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 5:03 am on June 2, 2015 Permalink | Reply
    Tags: , , , , Particle Physics   

    From ATLAS at CERN: Fast Forward tp Physics 

    CERN New Masthead

    As ATLAS gears up to record data from proton collisions delivered by the Large Hadron Collider (LHC) at an unprecedented energy level, here are glimpses from the last two years of preparations. For more information about the ATLAS Experiment please visit the official outreach page at http://www.atlas.ch

    Watch, enjoy, learn.

    See the full article here.

    Please help promote STEM in your local schools.

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    Meet CERN in a variety of places:

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New
    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New

    LHC

    CERN LHC New
    CERN LHC Grand Tunnel

    LHC particles

    Quantum Diaries

     
  • richardmitnick 9:55 am on May 29, 2015 Permalink | Reply
    Tags: , , , , Particle Physics   

    From CERN: “Major work to ready the LHC experiments for Run 2″ 

    CERN New Masthead

    29 May 2015
    Corinne Pralavorio

    1
    A magnet is lowered through the ALICE cavern for work on the Large Hadron Collider during Long Shutdown 1 (Image: Maximilien Brice/CERN)

    2
    Installation of a new layer of pixels in the ATLAS tracker (Image: Claudia Marcelloni/CERN)

    3
    The installation of the new pixel luminosity telescope in the CMS detector (Image: Maximilien Brice/CERN)

    4
    The reinstallation of the beam pipe in the LHCb detector (Image: LHCb)

    Next week, the experiments at the Large Hadron Collider (LHC) will be back in action, taking data for the accelerator’s second run. The experiments were shut down two years ago for maintenance and refurbishment in preparation for collisions at the higher energy of 13 teraelectronvolts (TeV).

    Long Shutdown 1 (LS1) saw hundreds of collaboration members working in and around the experiment caverns on improvements to the detectors. Four of these detectors – ALICE, ATLAS, CMS and LHCb – are enormous, sophisticated machines measuring up to 40 metres long and 20 metres long and made up of dozens of subdetectors, themselves composed of millions of sensitive sensors. Each subdetector is designed to determine the characteristics of one or more types of particle emerging from the particle collisions. These subdetectors include trackers, which reveal the paths of charged particles, and calorimeters, which measure the energy of some particles. All the data collected is grouped and analysed with a view to understanding what happened at the moment of collision. During the second run, up to one billion proton collisions could occur every second in the detectors. Most of the collisions do not yield interesting results and given the enormous quantities of data generated, it can’t all be logged. The trigger system therefore sorts the collisions, keeping just the most interesting events – several hundred per second. The data-acquisition system then records the data and sends it to the Worldwide LHC Computing Grid to be analysed by physicists. During the long shutdown, all these systems were verified and some were renovated or upgraded. Below is an overview of the main work projects that took place in the detector caverns ahead of the big restart.

    ALICE

    This experiment, which studies quark-gluon plasma – the matter present in the first moments of the universe’s existence – made improvements to most of its 19 subdetectors. One of these was the electromagnetic calorimeter, which measures the energy of the electrons, positrons and photons produced by the collisions. Its range of detection was extended with the addition of the new di-jet calorimeter. Modules were also added to other subdetectors, and tens of kilometres of cables were replaced as part of a complete overhaul of the electrical infrastructure. In terms of computing, ALICE doubled its data-logging capacity with improvements to the trigger and data-acquisition systems carried out by the collaboration’s IT experts.

    ATLAS

    The ATLAS detector can now see even better, thanks to a fourth layer of pixels in its pixel tracker, the subdetector closest to the collisions and whose function is to reconstruct the particle trajectories. Improvements were also made to the muon detectors and calorimeters, as well as to the entire basic infrastructure (including the electrical power supply and the cooling systems). Sections of the beam pipe, in which the protons circulate and collide, were replaced to reduce the background noise in the detector. With new, more efficient trigger and data-acquisition systems, ATLAS is ready to log more data than before: it will be capable of recording a thousand events every second – more than double its capacity during Run 1. In addition, an improvement plan to upgrade the simulation, reconstruction and data-analysis software used by physicists to conduct their research was carried out.

    CMS

    The CMS collaboration carried out important work on its tracker so that it can function at lower temperatures: it was fitted with a new leak-tightness system and a refurbished cooling system. The central section of the beam tube, where the collisions take place, was replaced with a tube of a smaller diameter to allow a new pixel tracker to be installed during the next long shutdown. A brand-new subdetector, the pixel luminosity telescope, was installed on either side of the detector and will enhance the experiment’s ability to measure luminosity (a measure of the number of collisions produced in the experiment). New muon chambers were installed and the hadron calorimeter, which measures the energy of particles containing quarks, was fitted with upgraded photodetectors. Last but not least, the trigger system was improved and the software and computing systems underwent a significant overhaul to reduce the time needed to produce analysis datasets.

    LHCb

    LHCb, the experiment that investigates beauty particles, added a HeRSChel detector along the beam line in order to identify rare processes in which particles are observed inside the detector but not along the beam line itself. The experiment’s beam pipe was also replaced, as was the pipe’s supporting structure, which is now lighter and more “transparent”. The experiments are constantly striving to achieve transparency as the detectors must detect without influencing the results, for example by intercepting particles that they’re not supposed to stop or by altering the trajectories.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

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    Meet CERN in a variety of places:

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New
    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New

    LHC

    CERN LHC New
    CERN LHC Grand Tunnel

    LHC particles

    Quantum Diaries

     
  • richardmitnick 4:08 pm on May 26, 2015 Permalink | Reply
    Tags: , , Particle Physics, , ,   

    From Symmetry: “A goldmine of scientific research” 

    Symmetry

    May 26, 2015
    Amelia Williamson Smith

    1
    Photo by Anna Davis

    The underground home of the LUX dark matter experiment has a rich scientific history.

    There’s more than gold in the Black Hills of South Dakota. For longer than five decades, the Homestake mine has hosted scientists searching for particles impossible to detect on Earth’s surface.

    It all began with the Davis Cavern.

    In the early 1960s, Ray Davis, a nuclear chemist at Brookhaven National Laboratory designed an experiment to detect particles produced in fusion reactions in the sun. The experiment would earn him a share of the Nobel Prize in Physics in 2002.

    Davis was searching for neutrinos, fundamental particles that had been discovered only a few years before. Neutrinos are very difficult to detect; they can pass through the entire Earth without bumping into another particle. But they are constantly streaming through us. So, with a big enough detector, Davis knew he could catch at least a few.

    Davis’ experiment had to be done deep underground; without the shielding of layers of rock and earth it would be flooded by the shower of cosmic rays also constantly raining from space.

    Davis put his first small prototype detector in a limestone mine near Akron, Ohio. But it was only about half a mile underground, not deep enough.

    “The only reason for mining deep into the earth was for something valuable like gold,” says Kenneth Lande, professor of physics at the University of Pennsylvania, who worked on the experiment with Davis. “And so a gold mine became the obvious place to look.”

    But there was no precedent for hosting a particle physics experiment in such a place. “There was no case where a physics group would appear at a working mine and say, ‘Can we move in please?’”

    Davis approached the Homestake Mining Company anyway, and the company agreed to excavate a cavern for the experiment.

    BNL funded the experiment. In 1965, it was installed in a cavern 4850 feet below the surface.

    The detector consisted of a 100,000-gallon tank of chlorine atoms. Davis had predicted that as solar neutrinos passed through the tank, one would occasionally collide with a chlorine atom, changing it to an argon atom. After letting the detector run for a couple of months at a time, Davis’ team would flush out the tank and count the argon atoms to determine how many neutrino interactions had occurred.

    “The detector had approximately 1031 atoms in it. One argon atom was produced every two days,” Lande says. “To design something that could do that kind of extraction was mind-boggling.”

    2
    Ray Davis. Courtesy of: Brookhaven National Laboratory

    A different kind of laboratory

    During the early years of the Davis experiment, around 2000 miners worked at the mine, along with engineers and geologists. The small group of scientists working on the Davis experiment would travel down into the mine with them.

    To go down the shaft to the 4850-foot level, they would get into what was called the “cage,” a 4.4-foot by 12.5-foot metal conveyance that held 36 people. The ride down, lit only by the glow of a couple of headlamps, took about five minutes, says Tom Regan, former operations safety manager and now safety consultant, who worked as a student laborer in the mine during the early years of the Davis experiment.

    Once they reached the 4850-foot level, the scientists walked across a rock dump. “It was guarded so a person couldn’t fall down the hole,” Regan says. “But you had to sometimes wait for a production train of rock or even loads of supplies or men or materials.”

    The Davis Cavern was 24 feet long, 24 feet wide, and 30 feet high. A small room off to the side held the group’s control system. “We were basically out of touch with the rest of the world when we were underground,” Lande says. “There was no difference between day and night, heat and cold, and snow and sunshine.”

    The miners and locals from Lead, South Dakota—the community surrounding the mine—were welcoming of the scientists and interested in their work, Lande says. “We’d go out to dinner at the local restaurant and we’d hear this hot conversation in the next booth, and they would be discussing black holes and neutron stars. So science became the talk of the small town.”

    4
    Davis Cavern, during the solar neutrino experiment. Photo by: Anna Davis

    The solar neutrino problem

    As the experiment began taking data, Davis’ group found they were detecting only about one-third the number of neutrinos predicted—a discrepancy that became known as the “solar neutrino problem.”

    Davis described the situation in his Nobel Prize biographical sketch: “My opinion in the early years was that something was wrong with the standard solar model; many physicists thought there was something wrong with my experiment.”

    However, every test of the experiment confirmed the results, and no problems were found with the model of the sun. Davis’ group began to suspect it was instead a problem with the neutrinos.

    This suspicion was confirmed in 2001, when the Sudbury Neutrino Observatory experiment [SNO] in Canada determined that as solar neutrinos travel through space, they oscillate, or change, between three flavors—electron, muon and tau. By the time neutrinos from the sun reach the Earth, they are an equal mixture of the three types.

    Sudbury Neutrino Observatory
    SNO

    The Davis experiment was sensitive only to electron neutrinos, so it was able to detect only one-third of the neutrinos from the sun. The solar neutrino problem was solved.

    5
    Davis Cavern, during a more recent expansion. Photo by: Matthew Kapust, Sanford Underground Research Facility

    A different kind of gold

    The Davis experiment ran for almost 40 years, until the mine closed in 2003.

    But the days of science in the Davis Cavern weren’t over. In 2006, the mining company donated Homestake to the state of South Dakota. It was renamed the Sanford Underground Research Facility.

    In 2009, many former Homestake miners became technicians on a $15.2 million project to renovate the experimental area. They completed the new 30,000-square-foot Davis Campus in 2012.

    Although scientists still ride in the cage to get down to the 4850-foot level of the mine, once they arrive it looks completely different.

    “It’s a very interesting contrast,” says Stanford University professor Thomas Shutt of SLAC National Accelerator Laboratory. “Going into the mine, it’s all mining carts, rust and rock, and then you get down to the Davis Campus, and it’s a really state-of-the-art facility.”

    The campus now contains block buildings with doors and windows. It has its own heating and air conditioning system, ventilation system, humidifiers and dust filters.

    The original Davis Cavern has been expanded and now houses the Large Underground Xenon experiment, the most sensitive detector yet searching for what many consider the most promising candidate for a type of dark matter particle.

    LUX Dark matter
    LUX

    Shielded from distracting background particles this far underground, scientists hope LUX will detect the rare interaction of dark matter particles with the nucleus of xenon atoms in the 368-kilogram tank.

    Another cavern nearby was excavated as part of the Davis Campus renovation project and now holds the Majorana Demonstrator experiment, which will soon start to examine whether neutrinos are their own antimatter partners.

    Majorano Demonstrator Experiment
    Majorano Demonstrator Experiment

    LUX began taking data in 2013. It is currently on its second run and will continue through spring 2016.

    After its current run, LUX will be replaced by the LUX-ZEPLIN, or LZ, experiment, which will be 50 times bigger in usable mass and several hundred times more sensitive than the current LUX results.

    LZ project
    LZ

    Science in the mine is still the talk of the town in Lead, says Carmen Carmona, an assistant project scientist at the University of California, Santa Barbara, who works on LUX. “When you go out on the streets and talk to people—especially the families of the miners from the gold mine days—they want to know how it is working underground now and how the experiment is going.”

    The spirit of cooperation between the mining community, the science community and the public community lives on, Regan says.

    “It’s been kind of a legacy to provide the beneficial space and be good neighbors and good hosts,” Regan says. “Our goal is for them to succeed, so we do everything we can to help and provide the best and safest place for them to do their good science.”

    6
    In 2010, Sanford Lab enlarged the Davis Cavern to support the Large Underground Xenon experiment. Matthew Kapust, Sanford Underground Research Facility

    7
    This cavern is being outfitted for the Compact Accelerator System Performing Astrophysical Research. CASPAR will use a low-powered accelerator to study what happens when stars die. Matthew Kapust, Sanford Underground Research Facility

    8
    Davis Cavern undergoes outfitting for the LUX experiment. Matthew Kapust, Sanford Underground Research Facility

    9
    Each day scientists working at the the Davis Campus pass this area, known as the Big X. The entrance to the Davis Campus is to the left; Yates Shaft is to the right. Matthew Kapust, Sanford Underground Research Facility

    10
    LUX researchers install the detector at the 4850 level. Matthew Kapust, Sanford Underground Research Facility

    11
    The Majorana Demonstrator experiment requires a very strict level of cleanliness. Researcher work in full clean room garb and assemble their detectors inside nitrogen-filled glove boxes. Matthew Kapust, Sanford Underground Research Facility

    12
    The LUX detector was built in a clean room on the surface and then brought underground. Matthew Kapust, Sanford Underground Research Facility

    See the full article here.

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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 8:28 am on May 22, 2015 Permalink | Reply
    Tags: , , , , , Particle Physics   

    From CERN: “First images of collisions at 13 TeV” 

    CERN New Masthead

    21 May 2015
    Cian O’Luanaigh

    1
    Test collisions continue today at 13 TeV in the Large Hadron Collider (LHC) to prepare the detectors ALICE, ATLAS, CMS, LHCb, LHCf, MOEDAL and TOTEM for data-taking, planned for early June (Image: LHC page 1)

    Last night, protons collided in the Large Hadron Collider (LHC) at the record-breaking energy of 13 TeV for the first time. These test collisions were to set up systems that protect the machine and detectors from particles that stray from the edges of the beam.

    A key part of the process was the set-up of the collimators. These devices which absorb stray particles were adjusted in colliding-beam conditions. This set-up will give the accelerator team the data they need to ensure that the LHC magnets and detectors are fully protected.

    Today the tests continue. Colliding beams will stay in the LHC for several hours. The LHC Operations team will continue to monitor beam quality and optimisation of the set-up.

    This is an important part of the process that will allow the experimental teams running the detectors ALICE, ATLAS, CMS, LHCb, LHCf, MOEDAL and TOTEM to switch on their experiments fully. Data taking and the start of the LHC’s second run is planned for early June.

    2
    Protons collide at 13 TeV sending showers of particles through the ALICE detector (Image: ALICE)

    3
    Protons collide at 13 TeV sending showers of particles through the CMS detector (Image: CMS)

    4
    Protons collide at 13 TeV sending showers of particles through the ATLAS detector (Image: ATLAS)

    5
    Protons collide at 13 TeV sending showers of particles through the LHCb detector (Image: LHCb)

    6
    Protons collide at 13 TeV sending showers of particles through the TOTEM detector (Image: TOTEM)

    See the full article here.

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    Meet CERN in a variety of places:

    Cern Courier

    THE FOUR MAJOR PROJECT COLLABORATIONS

    ATLAS
    CERN ATLAS New
    ALICE
    CERN ALICE New

    CMS
    CERN CMS New

    LHCb
    CERN LHCb New

    LHC

    CERN LHC New
    CERN LHC Grand Tunnel

    LHC particles

    Quantum Diaries

     
  • richardmitnick 2:53 pm on May 13, 2015 Permalink | Reply
    Tags: , , , , , , Particle Physics   

    From FNAL: “Two Large Hadron Collider experiments first to observe rare subatomic process” 

    FNAL Home

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

    May 13, 2015
    MEDIA CONTACTS
    Andre Salles, Fermilab Office of Communication, 630-840-3351, media@fnal.gov
    Sarah Charley, US LHC/CERN, +41 22 767 2118, sarah.charley@cern.ch

    SCIENCE CONTACTS
    Joel Butler, CMS experiment, Fermilab, 630-651-4619, butler@fnal.gov
    Sarah Scalese, LHCb experiment, Syracuse University, 315-443-8085, sescales@syr.edu

    1
    2
    Event displays from the CMS (above) and LHCb (below) experiments on the Large Hadron Collider show examples of collisions that produced candidates for the rare decay of the Bs particle, predicted and observed to occur only about four times out of a billion. Images: CMS/LHCb collaborations

    Two experiments at the Large Hadron Collider [LHC] at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland, have combined their results and observed a previously unseen subatomic process.

    CERN LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC

    As published in the journal Nature this week, a joint analysis by the CMS and LHCb collaborations has established a new and extremely rare decay of the Bs particle (a heavy composite particle consisting of a bottom antiquark and a strange quark) into two muons. Theorists had predicted that this decay would only occur about four times out of a billion, and that is roughly what the two experiments observed.

    CERN CMS Detector
    CMS

    CERN LHCb New II
    LHCb

    “It’s amazing that this theoretical prediction is so accurate and even more amazing that we can actually observe it at all,” said Syracuse University Professor Sheldon Stone, a member of the LHCb collaboration. “This is a great triumph for the LHC and both experiments.”

    LHCb and CMS both study the properties of particles to search for cracks in the Standard Model, our best description so far of the behavior of all directly observable matter in the universe.

    3
    Standard Model of Particle Physics. The diagram shows the elementary particles of the Standard Model (the Higgs boson, the three generations of quarks and leptons, and the gauge bosons), including their names, masses, spins, charges, chiralities, and interactions with the strong, weak and electromagnetic forces. It also depicts the crucial role of the Higgs boson in electroweak symmetry breaking, and shows how the properties of the various particles differ in the (high-energy) symmetric phase (top) and the (low-energy) broken-symmetry phase (bottom).

    The Standard Model is known to be incomplete since it does not address issues such as the presence of dark matter or the abundance of matter over antimatter in our universe. Any deviations from this model could be evidence of new physics at play, such as new particles or forces that could provide answers to these mysteries.

    “Many theories that propose to extend the Standard Model also predict an increase in this Bs decay rate,” said Fermilab’s Joel Butler of the CMS experiment. “This new result allows us to discount or severely limit the parameters of most of these theories. Any viable theory must predict a change small enough to be accommodated by the remaining uncertainty.”

    Researchers at the LHC are particularly interested in particles containing bottom quarks because they are easy to detect, abundantly produced and have a relatively long lifespan, according to Stone.

    “We also know that Bs mesons oscillate between their matter and their antimatter counterparts, a process first discovered at Fermilab in 2006,” Stone said. “Studying the properties of B mesons will help us understand the imbalance of matter and antimatter in the universe.”

    That imbalance is a mystery scientists are working to unravel. The big bang that created the universe should have resulted in equal amounts of matter and antimatter, annihilating each other on contact. But matter prevails, and scientists have not yet discovered the mechanism that made that possible.

    “The LHC will soon begin a new run at higher energy and intensity,” Butler said. “The precision with which this decay is measured will improve, further limiting the viable Standard Model extensions. And of course, we always hope to see the new physics directly in the form of new particles or forces.”

    This discovery grew from analysis of data taken in 2011 and 2012 by both experiments. Scientists also saw some evidence for this same process for the Bd particle, a similar particle consisting of a bottom antiquark and a down quark. However, this process is much more rare and predicted to occur only once out of every 10 billion decays. More data will be needed to conclusively establish its decay to two muons.

    The U.S. Department of Energy Office of Science provides funding for the U.S. contributions to the CMS experiment. The National Science Foundation provides funding for the U.S. contributions to the CMS and LHCb experiments. Together, the CMS and LHCb collaborations include more than 4,500 scientists from more than 250 institutions in 44 countries.

    The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

    The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2015, its budget is $7.3 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 48,000 competitive proposals for funding, and makes about 11,000 new funding awards. NSF also awards about $626 million in professional and service contracts yearly.

    CERN, the European Organization for Nuclear Research, is the world’s leading laboratory for particle physics. It has its headquarters in Geneva. At present, its Member States are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a Candidate for Accession. Serbia is an Associate Member in the pre-stage to Membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Union, JINR and UNESCO have Observer Status.

    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 6:44 pm on May 12, 2015 Permalink | Reply
    Tags: , Particle Physics,   

    From phys.org: “New shield makes certain types of searches for first time” 

    physdotorg
    phys.org

    May 12, 2015
    No Writer Credit

    1
    Inner three layers of the magnetic shield (also known as the insert), and the cylindrical layer with 780 copper rods. The cylindrical layer is used to generate a very uniform magnetic field, which is necessary for EDM experiments. Also shown are two measurement devices: A mercury magnetometer is placed between the wooden support structure, and a high precision pendulum device, which is used for the absolute alignment of conventional magnetic field probes, is on top of the support table. Credit: Technische Universität Müchen

    The Standard Model of particle physics, sometimes called “The Theory of Almost Everything,” is the best set of equations to date that describes the universe’s fundamental particles and how they interact.

    2
    Standard Model of Particle Physics. The diagram shows the elementary particles of the Standard Model (the Higgs boson, the three generations of quarks and leptons, and the gauge bosons), including their names, masses, spins, charges, chiralities, and interactions with the strong, weak and electromagnetic forces. It also depicts the crucial role of the Higgs boson in electroweak symmetry breaking, and shows how the properties of the various particles differ in the (high-energy) symmetric phase (top) and the (low-energy) broken-symmetry phase (bottom).

    Yet the theory has holes—including the absence of an adequate explanation for gravity, the inability to explain the asymmetry between matter and antimatter in the early universe, which gave rise to the stars and galaxies, and the failure to identify fundamental dark matter particles or account for dark energy.

    Researchers now have a new tool to aid in the search for physics beyond the good, but yet incomplete Standard Model. An international team of scientists has designed and tested a magnetic shield that is the first to achieve an extremely low magnetic field over a large volume. The device provides more than 10 times better magnetic shielding than previous state-of-the art shields. The record-setting performance makes it possible for scientists to measure certain properties of fundamental particles at higher levels of precision—which in turn could reveal previously hidden physics and set parameters in the search for new particles.

    The researchers describe the new magnetic shield in a paper in the Journal of Applied Physics.

    High precision measurements are one of three frontiers to search for physics beyond the Standard Model, explained Tobias Lins, a doctoral student who worked on the new magnetic shield in the research lab of Professor Peter Fierlinger at the Technische Universität München in Germany. The precision measurements complement other methods to search for new physics, including slamming particles together in a collider to generate new, high-energy particles, and peering into space to catch signals from the early universe.

    “Precision experiments are able to probe nature up to energy scales which might not be accessible by current and next generation collider experiments,” Lins said. That’s because the existence of exotic new particles can slightly alter the properties of already known particles. A tiny deviation from the expected properties may indicate that an as-yet-undiscovered fundamental particle inhabits the “particle zoo.”

    2
    An international team of physicists has developed a shielding that dampens low frequency magnetic fields more than a million-fold. Using this mechanism, they have created a space that boasts the weakest magnetic field of our solar system. The physicists now intend to carry out precision experiments there. Credit: Astrid Eckert / TUM

    Constructing the Shield

    The researchers built the new shield out of several layers of a special alloy, composed of nickel and iron, that has a high degree of magnetic permeability—meaning it can act like a sponge to absorb and redirect an applied magnetic field, like the earth’s own magnetic field or fields generated by equipment such as motors and transformers.

    “The apparatus might be compared to cuboid Russian nesting dolls,” Lins said. “Like the dolls, most layers can be used individually and with an increasing number of layers the inside is more and more protected.”

    The team’s big breakthrough came from in-depth numerical modeling of the arrangement of the precision treated magnetizable alloy, resulting in significantly optimized design details, like thickness, connections and spacing of layers.

    The materials in magnetic shields change their magnetization due to environmental influences, like temperature changes and vibrations caused by passing cars, and these shifts can be passed to the inside of the shield. The thinner sheets in the new design enabled a better balancing of the magnetic field in the metal, resulting in the smallest and most homogenous magnetic field ever created within the shielded space, even beating the average ambient magnetic field of the interstellar medium.

    New Experiments Ahead

    Plans are already underway to use the new magnetic shield in an experiment to test limits for the distribution of charges (called the electric dipole moment or EDM) of an isotope of xenon. An EDM that is higher than predicted by the Standard Model could signal the existence of a new particle whose mass is linked to the amount by which the EDM deviates from the expected value.

    The researchers also want to use a modified SQUID detector—which can detect extremely subtle magnetic fields—to search for long theorized, but never detected magnetic monopoles. Within the magnetically quiet space inside the shield, a monopole passing by the SQUID might produce a magnetic field higher than the background noise level, Lins said.

    See the full article here.

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    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

     
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