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PDF Version for Printing Fermilab Today Friday, March 12, 2010 Subscribe | Contact Us | Archive | Classifieds | Guidelines | Help Search Calendar CMS Result of the Month Recovery Act Feature Have a safe day! The strangest thing we’ve ever Wilson Hall to receive new Friday, March 12 seen emergency generator 11 a.m. Special Joint Experimental- Theoretical Physics Seminar - One West Speakers: Matthew Herndon, University of Wisconsin, Gregorio Bernardi, LPNHE, University of Paris Title: Joint CDF/DZero Seminar: New Results (to be) Presented at Winter Conferences 3:30 p.m. Fermilab obtained the current emergency DIRECTOR'S COFFEE generators in Wilson Hall as government surplus from the Korean War. BREAK - 2nd Flr X-Over 4 p.m. CMS has observed the Ξ baryon by looking for After close to 60 years in service, the Joint Experimental-Theoretical events containing both lambda baryons and pi emergency backup generators in Wilson Hall Physics Seminar - One West mesons. If these two particles are observed and will retire this spring. came from a single parent particle, we expect to Speaker: Clem Pryke, see a narrow peak in our data. This measurement First used in the Korean War in the 1950s, University of Chicago used data taken in December, including the data Fermilab obtained the two generators in 1975 Title: First Direct Search for taken during the period when the LHC ran at from government surplus and made them key Gravitation Modes in the CMB record-breaking energy, 20 percent higher than the components in the emergency power system Polarization Tevatron. in Wilson Hall. But after years of ever- Some things are far stranger than others, and increasing maintenance and questionable Monday, March 15 this week I’m reporting on the strangest thing reliability, Fermilab will remove the two THERE WILL BE NO CMS has seen so far. “Strange” in this context generators and replace them with a single, PARTICLE ASTROPHYSICS doesn’t mean “weird” but rather describes diesel-powered one. SEMINAR THIS WEEK something about the quarks inside the newly 3:30 p.m. rediscovered particle. “The generators run our fire pumps and are a DIRECTOR'S COFFEE very important safety unit in case of an BREAK - 2nd Flr X-Over There are many particles that are produced at emergency,” said Fermilab engineer Jim 4 p.m. the LHC. One particular type is called the Niehoff. “Replacing the old generators with a All Experimenters' Meeting - baryon. Baryons are a class of particles that single unit will greatly increase reliability.” Curia II contain exactly three quarks. The most familiar Special Topics: Completion of baryons are the proton and neutron, which are With funding provided by the American ArgoNeuT Run; NuMI Target made of up and down quarks. Indeed, the up Recovery & Reinvestment Act, Fermilab Pile Cooling and down quarks are all that is necessary to purchased the new generator from Patten make up our universe. However, we know that Industries, a local distributor for Caterpillar, for Click here for NALCAL, four other kinds of quarks exist: strange, roughly $150,000. Fermilab awarded the a weekly calendar with charm, bottom and top. Finding particles with contract for the excavation and removal of the links to additional these additional quarks is an important way- old generators and the installation of the new information. station in the CMS collaboration’s journey to one to Pandecon, Inc. in North Aurora for roughly $260,000. Upcoming conferences fully understanding our detector. Campaigns One interesting particle is the Ξ (the Greek Similar to the type of emergency generator letter xi) baryon. Discovered in 1964, this type that hospitals use, the new unit will provide emergency power to Wilson Hall for 24 to 36 of particle is also called the cascade particle hours, depending on the electrical demand in because of its distinctive decay pattern. All the building. “If the electricity gets cut off, the baryons contain three quarks, but in order to generator automatically comes on in 10 file:///U|/wwwdocs/pub/v5_0/today/archive_2010/today10-03-12.html (1 of 4)3/12/2010 10:18:55 AM Fermilab Today be a Ξ baryon, two of those quarks must be seconds,” said Greg Klyczek of Patten Take Five strange quarks. Scientists observe these Industries. particles by their decay into a π (pi) meson A crew of 14 workers from Pandecon, Inc. will Tune IT Up λ and a (lambda) baryon. The lambda baryon first remove the old generators and then install contains a single strange quark and CMS the new one, which weighs about 30,000 collaborators observed the lambda baryon in pounds and is roughly the size of a small train H1N1 Flu December. car. It will reside outside Wilson Hall, adjacent to the southwest corner of the building. Visual CMS physicists searched in their data, looking For information about H1N1, screening and landscaping will be added after for collisions in which lambda baryons and pi visit Fermilab's flu information the construction project is complete. site. mesons were created. They then asked the question “If these two particles were the decay Excavation of the area is scheduled to begin Weather product of a single particle, what would be the next week. Drivers and pedestrians should mass of the parent particle?” They then plotted take caution and be aware of the construction the mass of the potential parent. If the two that will occur on the west side of the building. Showers particles didn’t have a single parent, all 55°/41° masses would occur with nearly equal Pandecon, Inc. expects to hook up the new frequency. However, if they had a single Extended Forecast generator in June. parent, we expect to see a narrow peak on a Weather at Fermilab wide background. As seen in the figure above, -- Elizabeth Clements Current Security these scientists clearly observed the Ξ baryon Status with the mass we expect from earlier Announcements measurements. Secon Level 3 Watch your mail station for the With this success, CMS continues its arrival of your Fermilab Statement of Wilson Hall Cafe rediscovery of the Standard Model. Benefits Friday, March 12 -- Don Lincoln Employee Discount at Batavia - Chorizo burrito Rosati's - Chunky vegetable soup w/ orzo Harlem Globetrotters Special Ticket - Buffalo chicken wings - Cajun breaded catfish Price - April 15 - Teriyaki pork stir-fry Qi Gong, Mindfulness and Tai Chi - Honey mustard ham & swiss panini Easy for Stress Reduction - Assorted slices of pizza - Carved turkey These physicists from the University of Colorado, Fermilab Management Practices Boulder, performed this search for Ξ baryons. seminar beginning Feb. 11 Wilson Hall Cafe menu Chez Leon International Folk Dancing, Thursday evenings at Kuhn Barn Wednesday, March 17 Lunch Argentine Tango through March 31, - Orange-herb game hens student discount - Buttered green beans - New potatoes Hiring summer students for 2010 - Key lime pie Calling all softball players Thursday, March 18 Dinner Robert Oppenheimer play at - Bacon, potato & gruyere Waubonsee in Sugar Grove - March 20 souffle - Medallions of beef with morel Influence and Motivation: The sauce Empowering Leader course offered - Parmesan orzo March 24 - Steamed asparagus - Creme brulee PowerPoint 2007 Advanced course offered March 25 Chez Leon menu file:///U|/wwwdocs/pub/v5_0/today/archive_2010/today10-03-12.html (2 of 4)3/12/2010 10:18:55 AM Fermilab Today Call x3524 to make your English country dancing - Sunday, reservation. March 28 Archives Requesting donations for Fermi Maternity Closet Fermilab Today Excel Programming with VBA class offered March 30 and April 1 Result of the Week March 31 deadline to enroll young adult dependents Safety Tip of the Week Intermediate/Advanced Python User University Profiles Programming offered May 19-21 Interpersonal Communication Skills ILC NewsLine offered March 16 Word 2007 Advanced class offered Info March 16 Fermilab Today Fermilab Blood drive had a $100 gas is online at: card winner www.fnal.gov/today/ DreamWeaver CS3: Intro offered Send comments and March 16 suggestions to: These physicists played important roles in track [email protected] reconstruction in the first collisions at CMS. Facilitating Meetings That Work Efficient track reconstruction makes this and many course offered March 17 Visit the Fermilab other analyses possible. In the News home page Additional activities A first look at the Earth interior from the Gran Sasso Submit an announcement underground laboratory From INFN, posted Mar. 11, 2010 Classifieds Find new classified ads on Fermilab Today. The Borexino Collaboration announced the observation of geo-neutrinos at the underground Gran Sasso National Laboratory of Italian Institute for Nuclear Physics (INFN), Italy. The data reveal, for the first time, a definite anti-neutrino signal with the expected energy spectrum due to radioactive decays of U and Th in the Earth well above background. The International Borexino Collaboration, with institutions from Italy, US, Germany, Russia, Poland and France, operates a 300-ton liquid- scintillator detector designed to observe and study low-energy solar neutrinos. The low background of the Borexino detector has been key to the detection of geo-neutrinos. Technologies developed by Borexino Collaborators have achieved very low background levels. The central core of the Borexino scintillator is now the lowest background detector available for these observations. The ultra-low background of file:///U|/wwwdocs/pub/v5_0/today/archive_2010/today10-03-12.html (3 of 4)3/12/2010 10:18:55 AM Fermilab Today Borexino was developed to make the first measurements of solar neutrinos below 1 MeV and has now produced this first, firm observation of geo-neutrinos. Read more file:///U|/wwwdocs/pub/v5_0/today/archive_2010/today10-03-12.html (4 of 4)3/12/2010 10:18:55 AM.
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