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August 27, 2008
iSGTW Feature - Tevatron Higgs update August 08

Feature - Tevatron brings Higgs one step closer The Tevatron at Fermilab in Batavia, Illinois, U.S.. Image courtesy of Fermilab. On June 4 we reported that teams from CDF and DZero at Fermilab, aided by processing power from the Open Science Grid, had jointly amassed enough data at that time to state with 90% certainty that the Higgs boson, the particle that could help explain dark matter, dark energy and why particles have mass, does not have the expected mass of 160 GeV/c2. This hot topic in particle physics is getting hotter. Here we give an update.Scientists from the CDF and DZero collaborations at the Tevatron at Fermilab presented results which for the first time exclude, with 95% probability, a mass for the Higgs of 170 GeV/c2. This value lies near the middle of the possible mass range for the particle established by earlier experiments. “These results mean that the Tevatron experiments are very much in the game for finding the Higgs,” said Pier Oddone, director of Fermilab. Combining results from the two coll

August 20, 2008
iSGTW - Image of the Week: One view of the LHC

  Image of the week - One view of the LHC (Click on this link or the photo above to get the rotating, 360-degree, panoramic view, with natural sound.)One view of the Large Hadron Collider To give an idea of the enormity of the project at CERN, Peter McCready took a series of panoramic views of each of the  experiments. Last week, we showed ALICE, here's a view of one portion of the LHC. McCready creates these images using digital cameras mounted atop a customized tripod apparatus that allows him to take wrap-around images of up to a complete 360 rotation. Each image requires more than one hundred separate, individual photoraphs to be shot, which are then stitched together to form one seamless spherical image. The completed photo takes up 40MP. Image courtesy of Peter McCready    

August 20, 2008
iSGTW Feature - People behind the LHC grid: Jamie Shiers

Feature - People behind the LHC grid: Jamie Shiers Some of the different projects involved, from across the globe. Image courtesy of Jamie Shiers Jamie Shiers is part of grid support for the Large Hadron Collider, and has been working on the LHC for 16 of his 25 years at CERN. Dressed in sneakers and jeans, and looking tan after a recent grid conference in Brazil, he talked with iSGTW at CERN’s Restaurant 1.  iSGTW: What first got you interested in physics? JS: It could be something in the genes, I suppose. I and two of my three brothers  became physicists—and we’ve all passed through CERN.  For me, what helped to get me hooked was a book about physics, called “Mister Tompkins in Wonderland,” that I read at age 14 or 15, by George Gamow—a Russian physicist who worked with Niels Bohr. He wrote about a world in which light was slowed down enough that you could see the effects of relativity. It was a great book that turned me on to physics . . . that, and the old c

August 13, 2008
iSGTW Feature - Almost starting-up the LHC

Feature - (Almost) starting up the LHC: a view from the front lines A welder works on the interconnection between two of the LHC's superconducting magnet systems, in the LHC tunnel, earlier this year. Image courtesy of CERN On Thursday, 8 August, CERN announced that it would make the first attempt to circulate a beam in the Large Hadron Collider (LHC) on 10 September, with the first test scheduled for the weekend of 9 August.To find out what it is like from the point of view of those actually building the LHC and installing the equipment, iSGTW caught up with Mike Lamont of LHC Machine Operations for a few minutes, just  before workers were about to start the initial steps of a preliminary, low-energy, “pre-startup.” iSGTW: What are your feelings, after all this time and effort?Lamont: “At the moment, my general feeling is an overwhelming one of relief, actually. We’ve pulled all the bits together; we’ve got the ring more or less cooled now; we’re underway.”“We’re up t

July 9, 2008
Image of the Week - Back to the big bang at the LHC

Image of the week - Back to the Big Bang Image courtesy of Neason O'Neill Last week the Royal Society held its annual Summer Science exhibition in central London. With 23 science exhbitis, two art exhibits and two history of science exhibits, several thousand visitors got the chance to meet and talk to the researchers behind the best of the UK’s science and technology research.This year the Large Hadron Collider and the grid were on display with the “Back to the Big Bang? At the Large Hadron Collider” exhibit organised by the UK’s Science and Technology Facilities Council.Full details of all the science on display this year is available on the exhibition’s Web site http://www.summerscience.org.uk/. Next year’s Summer Science Exhibition will take place from Tuesday 30 June to Saturday 4 July 2009.. 

June 4, 2008
iSGTW Feature - Higgs search at Tevatron

Feature - Friendly but fierce competition for the Higgs This diagram plots the limit (at 95% confidence level) of Higgs production (y-axis) for different possible Higgs masses (x-axis). Each mark along the y-axis is a multiple of the Standard Model rate of Higgs production, and this rate is shown as a straight line at "1." The more data Fermilab scientists collect, the closer their observed limits will get to the Standard Model rate.  Notice that the "observed" line comes vertically closest to 1, the Standard Model rate, at 160 on the x-axis. Fermilab physicists have amassed nearly enough data to make a statement about whether the Higgs exists at the mass value 160 GeV/c2.Image courtesy of the  Tevatron New Phenomena & Higgs Working Group on behalf of CDF and D0. The two Tevatron experiments at Fermilab, CDF and D0, have nearly ruled out the hoped-for mass value for the Higgs boson—the particle regarded by some as one of the last big mysteries of the universe. Its disc

May 21, 2008
iSGTW Feature - CMS data transfer

Feature - CMS readies network links for LHC data CMS data transfer rate in MB/s during the data transer debugging task, from September through November 2007.Image courtesy of CMS. Transfer 300 thousand million bytes (300 Gigabytes) per day for six out of seven consecutive days and move a total of 2.3 Terabytes during that same seven-day period—that’s 2.3 million million bytes—these are the criteria that each major network link in the Compact Muon Solenoid’s computing structure must satisfy when the Large Hadron Collider turns on this summer. Together they will transfer tens of Terabytes a day.The CMS computing structure comprises an internationally distributed system of services and resources that interact over the network through the Worldwide LHC Computing Grid (WLCG). The three-tiered architecture, fetchingly illustrated in a Flash animation from the GridCafe, functions as a single coherent system. Data collected at CERN, the top tier (dubbed Tier-0), is distributed to a set of seven

May 14, 2008
iSGTW Feature - No business like show business

Feature - No business like show business: Final rehearsal for WLCG Before the show can go on, there must be extensive, full-scale dress rehearsals. For the Worldwide LHC Computing Grid, that means several Common Computing Readiness Challenges.Stock image courtesy of sxc.chu  Rehearsal, rehearsal Opening night Like a theatrical company on the eve of a big new production, CERN's Computing Centre and its partner computing sites are preparing for their opening night.  This summer, the two stars of their show will mark their debuts: The Large Hadron Collider ─ largest particle accelerator built to date ─  will start up, and the Worldwide LHC Computing Grid (WLCG) will collect, move and process the massive amount of data the LHC generates. In the next few months, final touches will be added to ensure that the WLCG and the people involved with it can put on their best performance, says Jamie Shiers, responsible for overall coordination of the system’s practice runs ─

May 7, 2008
iSGTW Feature - Cell biologists dig new DiGS

  Feature - Cell biologists dig new DiGS Cell biologists at the University of Edinburgh and University of Oxford are using grid technology called DiGS to support their investigation into the transport and anchoring of mRNA in Drosophila flies. Image courtesy of Wikipedia As cell biology moves from labs to computer desktops, researchers must deal with increasingly vast volumes of data. Traditional ways of sharing this data—such as physically shipping hard drives—just cannot keep up. UK Quantum Chromodynamics has been working to solve these data management challenges using grid technology since 2002, developing QCDGrid to share, publish and preserve their large datasets. And although UKQCD are a physics outfit, they’ve made their software—renamed DiGS or Distributed Grid Storage—available to the wider scientific community.First off the block: biology“The EPCC team focused initially on the needs of particle physicists,” explains George Beckett of the Edinburgh P

May 7, 2008
iSGTW Feature - Testing the limits of the Standard Model

  Feature - Testing the limits of the Standard Model This frame is from an animation illustrating the typical four-dimensional structure of gluon-field configurations used by Sugar and his research group. Image courtesy of Derek Leinweber, CSSM, University of Adelaide. Questions about the Standard Model of physics have stymied scientists for decades, but now, thanks to supercomputing grid technology, Robert Sugar believes we’ll have answers in just five to ten years.Sugar, a professor of physics at the University of California, U.S., is a TeraGrid user and member of the MILC Collaboration, one of the largest users of open-science computing in the world. MILC first turned to computers for their calculations in the 1980s, believing only supercomputers could solve their intractable problems. “There was a long period where people were developing the tools and algorithms, but not producing results that were accurate enough to have an impact on experiments,” Sugar recalls. “But that&rsq

April 23, 2008
iSGTW Feature - International Summer School on Grid Computing: looking back, one year on

  Opinion - International Summer School on Grid Computing: looking back, one year on Thanks to his ISSGC’07 experience, Andrew Jamieson and his colleagues are actively pursuing the possibility of gridifying aspects of their medical research work.Image courtesy of Andrew Jamieson Deadlines for the 2008 International Summer School on Grid Computing close on 5 May. Here, former student Andrew Jamieson reflects on his experiences at the 2007 summer school, held in Sweden. In 2007, with the aid of the Open Science Grid, I attended the International Summer School on Grid Computing in Sweden. Today, just over a year later, I am still involved in grid computing.My scientific background as a medical physicist researcher involves developing accurate computer-aided diagnosis (CAD) algorithms for breast mass lesions in X-ray mammography, ultra sound and MRI images. My colleagues and I are interested in using grid computing to push CAD and image analysis to a new level of exploratory power and scientific evalua

April 23, 2008
iSGTW Link of the week - Salute to SALUTE

 

Link of the week - Salute to SALUTE

The Bulgarian team in charge of the SALUTE project is developing algorithms for studying quantum effects in semiconductor structures. These effects influence the design of nano-devices with improved performance.Images courtesy of SALUTE and Obscura

SALUTE—or Stochastic ALgorithms for Ultra-fast Transport in sEmiconductors—is a pilot grid application developed to solve computationally intensive problems in semiconductor physics.
Semiconductors—materials that can both conduct and insulate electricity—are invaluable to modern electronics. Their ability to conduct depends on the ability of “carriers”—electrons or phonons—to transport electrical charge.This carrier transport occurs on a quantum level: the temporal scale is so short it is measured in femtoseconds, where one femtosecond is 10-15 seconds, or one millionth of a nanosecond.
Simulations on this sort of scale rely on complicated integral eq

April 9, 2008
iSGTW Image of the week: FOCUS on fire

Image of the week - FOCUS on fire This image shows a flame held by a flameholder. The FOCUS project simulations have demonstrated that taking radiation into consideration when making calculations modifies the dynamics of the flame. Image courtesy of FOCUS Combustion is hot stuff, playing a part in more than 80 percent of primary energy conversion processes worldwide; however, the way things burn remains a complex phenomenon, characterized by instabilities and side effects, such as pollutant formation and radiative heat transfer.Hot computingComplex numerical simulations are used to aid the design of industrial combustors, and now a team of researchers is using Europe’s DEISA e-infrastructure to make these simulations even more accurate.The team, a collaboration between Olivier Gicquel’s team at the EM2C laboratory of the Ecole Centrale Paris and the IDRIS team at CNRS in France, say CPU-power fueled their results. “The DEISA project gave us access to the coupling technology that we required,” says Gicquel. “It also provided u

March 5, 2008
iSGTW Feature - Introducing TRIUMF: Canada's Tier-1 on the worldwide grid

  Feature - Introducing TRIUMF: Canada’s Tier-1 on the worldwide grid Lead system administrator Denice Deatrich and networking administrator Chris Payne examining the dCache servers at the TRIUMF Tier-1 center.Image courtesy of TRIUMF When the Large Hadron Collider starts up at CERN in 2008, the world will be waiting to receive the data it produces. In Canada, researchers will be looking to TRIUMF, Canada’s particle and nuclear physics national laboratory. TRIUMF is host to one of eleven Tier-1 centers, forming an integral part of the Worldwide LHC Computing Grid collaboration and supporting the particle detector experiment, ATLAS, one of the LHC-powered experiments.With its experience supplying 24/7 service to international collaborations, TRIUMF provides the facilities required for the large-scale, data-intensive analysis that LHC data will require, while attracting expertise in the operation of the facilities as well as for user-support. High-density, liquid-cooled   Uniquely, TRIUMF’s Tier-1 cente

February 6, 2008
iSGTW Feature - Computing the unseen: the search for dark matter

  Feature - Computing the unseen: the search for dark matter Researchers are using the Collider Detector at Fermilab detector to help in the search for dark matter, hoping to observe a Bs particle decay, which could provide evidence of supersymmetry and dark matter. Image courtesy of FermilabThink you’ve seen it all? Think again. Everything we can see and detect makes up only four percent of the universe, according to Michael Weinberger, a physicist at Texas A&M University and member of the Collider Detector at Fermilab collaboration. Weinberger and his CDF colleagues are conducting a search that could shed light on the universe’s “dark matter”—material that doesn’t emit or reflect radiation but is predicted by astrophysical observations to outnumber visible matter by nearly six-to-one—and they are using grid technology to expedite their hunt. The elusive Bs decayThe key to the search is the ability to measure the rate at which Bs particles decay to form two muons. According to t

January 16, 2008
iSGTW Feature - I2U2: educational e-Labs for real pre-college e-science

  Feature - I2U2: educational e-Labs for real pre-college e-science Students participating in an I2U2 QuarkNet e-Lab must construct their own cosmic ray detector, devise their own research questions and decide how to analyze their data and what to do with the results. More than 290 QuarkNet units are in place in schools around the U.S., with another 40 scattered in schools around the world. Image courtesy of QuarkNet Taking science out of the lab and injecting it into schools, Interactions in Understanding the Universe—better known as I2U2—is transforming pre-college education.  An Open Science Grid virtual organization dedicated to providing teachers and students with the data and tools used by large scientific collaborations, I2U2 also introduces high school students to the power of grid-enabled e-research. Real science, real data, real grids“The aim is to foster the experience of participating in scientific enterprise and the scientific community,” explains Tom Loughran, I2U2 education program l

December 5, 2007
iSGTW Feature - Open Science Grid crunches through CMS simulations

  Feature - Open Science Grid crunches through CMS simulations OSG-based event production accounting for over half of all fully simulated CMS events produced in 2007. The remaining production was done by regional teams working on LCG sites. The CMS collaboration involves 37 countries, 155 institutes and more than 2000 scientists. Images courtesy of Open Science Grid In the lead-up to the launch of the Large Hadron Collider and the four massive physics projects that depend on it, scientists around the world have been giving their data-processing muscle a serious workout, with superb results.As part of the Compact Muon Solenoid experiment, Open Science Grid scientists are crunching through Monte Carlo simulations of what might happen when protons collide inside the CMS detector. Millions of proton collisions must be simulated to gather a meaningful result.The use of OSG resources to simulate these events continues to be a spectacular success, with OSG-based event production accounting for over half of all fully simulated CMS e

November 14, 2007
iSGTW Links of the week: The latest on the Large Hadron Collider

Links of the week - The latest on the Large Hadron Collider The LHC project is the first large-scale scientific endeavor to depend on the success of grid computing for its own success. Screen shot courtesy of US/LHC The latest on the Large Hadron Collider—which is set to become the world’s most powerful particle accelerator when it starts up in 2008—is increasingly available in living rooms around the planet.LHC news, updates and resources are now available from an international trio of Web sites produced by CERN, the UK and the most recent, released last month by the U.S.You can also track the progress of the project using LHC milestones. Coming to proton-crunch time For more than a decade, an international team of thousands of scientists, engineers, technicians and students has been designing, constructing and assembling the 27-kilometer-long LHC and the four huge experiments it will host. Alongside this effort, a slightly smaller, but no less dedicated, team of computer scientists and computing-savvy phy

November 14, 2007
iSGTW Opinion - Me, my friends, our grid: bringing people together for great science

  Opinion - Me, my friends, our grid: bringing people together for great science “The biggest challenges in grid technology are not technological; they’re social. Building new communities is as important as building new computer centers.” Image courtesy of Graham Ramsay Frank Würthwein is a particle physicist with University of California San Diego and a user of Open Science Grid. He is also the OSG applications coordinator and a member of the CMS collaboration at the Large Hadron Collider, and says grids are as much about sociology as they are about science.As the clock ticks towards startup for the Large Hadron Collider, particle physics draws ever closer to what many hope will be a revolution for the field: a giant step forward in our understanding of the universe.For many physicists, the greatest fear is that we will find the Higgs Boson, and that in the wake of this success, nothing will change. More exciting, more fascinating, is the possibility that finding the Higgs will bring with it a new pa

November 7, 2007
iSGTW Image of the week - All about ALICE

Image of the week - All about ALICE Recreating the conditions that existed microseconds after the Big Bang, ALICE aims to unlock a new understanding of the fundamental nature of matter and the universe.Image courtesy of Peter McCready Also known as A Large Ion Collider Experiment, ALICE is a massive physics experiment that will help physicists learn more about how matter was created and what it is made of.ALICE will allow researchers to study the primordial “soup” of elementary particles that existed microseconds after the Big Bang.Called Quark-Gluon Plasma, this cosmic “soup” is created when protons and neutrons melt into new forms of matter. This occurs at temperatures 100,000 times hotter than the center of the Sun, and under enormous pressures: so great that the pyramid of Kheops could be compressed into a pinhead. Enter the LHCThese extraordinary conditions will be created inside the Large Hadron Collider, an underground particle accelerator that will become the world’s largest machine when it st

October 17, 2007
iSGTW Announcement - LHCathome makes new home in the UK

  Announcement - LHC@home makes new home in the UK LHC@home seeks to engage the community in the global effort to further physics, enabling volunteers to run SixTrack simulations of physics inside the Large Hadron Collider from the comfort of their own home.Images courtesy of LHC@home Researchers in the UK are gearing themselves up for an influx of help with the recent arrival of the successful LHC@home volunteer computing project at the Queen Mary University of London in England. Forty thousand people from more than 100 countries have already contributed the equivalent of about 3000 years on a single computer to LHC@home, which is migrating from its first home at CERN, the European particle physics laboratory in Geneva, Switzerland. Running off the BOINC platform, LHC@home uses volunteer computing power to model the progress of sub-atomic particles traveling at nearly the speed of light around Europe’s newest particle accelerator, the Large Hadron Collider (LHC).Lyn Evans, head of the LHC project, says that, &ldqu

September 26, 2007
iSGTW Feature - Fusion of disciplines powers Russian grid infrastructure

  Feature - Fusion of disciplines powers Russian grid infrastructure The Fusion_RDIG virtual organization works to help Russian researchers working on the international ITER project. The ITER fusion device has been designed to produce 500 MW of fusion power; construction should commence in 2008.Image courtesy of ITER Established in September 2003, development of RDIG, or the Russian Data Intensive Grid, was at first driven by the high energy physics community, which still remains the largest user of the RDIG infrastructure.Four years on, demand for RDIG infrastructure is now coming from scientists in nanotechnology, computational chemistry, biology, earth sciences, business and more. The feasibility of fusion powerIgor Semenov, head of the Department of Physics and Engineering Problems at Russian Research Center “Kurchatov Institute” (RRC KI), Russia’s lead governmental organization for nuclear research, says grid computing has been a boon for his team’s research.“The load on RRC KI computing re

September 19, 2007
iSGTW Feature - ATLAS: the data chain works

  Feature - ATLAS: the data chain works Tracks recorded in the muon chambers of the ATLAS detector can now be expressed to physicists all over the world, enabling simultaneous analysis at sites across the globe. The European and U.S. sites are connected via the Enabling Grids for E-sciencE and Open Science Grid infrastructures.Image courtesy of ATLAS This month particle physics experiment ATLAS went “end-to-end” for the first time. Buried in Switzerland, 90 meters under the ground at the base of the French Jura mountains, ATLAS (A Torroidal LHC ApparatuS) is one of four high energy physics experiments attached to the Large Hadron Collider, a 27-kilometer particle accelerator nearing the final stages of completion.When the LHC is turned on, physicists worldwide will be waiting by their computers. They’ll be expecting express and non-stop delivery of massive amounts of data, streamed in a virtually seamless sequence direct to their doorstep.And this month, for the first time, ATLAS proved that this data dist

September 19, 2007
iSGTW Feature - Coming ready or not: will we be ready for the LHC?

  Feature - Coming ready or not: will we be ready for the LHC? The GridPP team are assessing the readiness of clusters across the UK, including this cluster at Birmingham University, part of SouthGrid.Image courtesy of GridPP With the Large Hadron Collider starting up next year, grid sites worldwide are ramping up their equipment and service levels in preparation for an expected flood of data. But, will they be ready—and can any problems they’re having be fixed in time? GridPP tests its readinessIn the UK, a team from GridPP, the UK particle physics grid, has recently completed a round of visits to 17 GridPP sites, aiming to assess how ready they are for the onslaught of data that will mark the beginning of the Large Hadron Collider experiment. Dave Britton, GridPP’s Project Manager, coordinated the process. “We wanted to check that each site would be ready for next year, and find out how we could help with any difficulties. The best way to do this was to visit each site individually, so we could tal

September 12, 2007
iSGTW Feature - Six petabytes: Fermilab hits new record

Feature - Six petabytes: Fermilab hits new record The volume of data sent from the Tier-1 Fermilab computing center to Tier-2 sites continues to increase. The sites form part of the international grid being constructed in readiness for the start-up of the Large Hadron Collider.Image courtesy of FermilabThe U.S. national accelerator laboratory Fermilab recently reached a record six petabytes—six million gigabytes—of data permanently recorded on tape, while data sent from the lab exceeded two petabytes, more than double the amount leaving the lab three months earlier.“Our traffic has been growing in terms of the amount of bytes we move onto the site as the Large Hadron Collider and Compact Muon Solenoid experiments ramp up,” said Matt Crawford, the department head for Data Movement and Storage in Fermilab’s Computing Division.Prior to a year ago, traffic never exceeded a fourth of a petabyte in a month, Crawford said. He attributes the increase in both outgoing and incoming data to CMS, DZero and Collid