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ATLAS Experiment ATLAS Experiment Control room ATLAS building M. Barnett – February 2008 1 Final piece of ATLAS lowered last Friday (the second small muon wheel) M. Barnett – February 2008 2 M. Barnett – February 2008 3 Still to be done Connecting: Cables, Fibers, Cryogenics M. Barnett – February 2008 4 Celebrations M. Barnett – February 2008 5 News Coverage News media are flooding CERN well in advance of startup "Particle physics is the unbelievable in pursuit of the unimaginable. To pinpoint the smallest fragments of the universe you have to build the biggest machine in the world. To recreate the first millionths of a second of creation you have to focus energy on an awesome scale." The Guardian M. Barnett – February 2008 6 Three full pages in New York Times M. Barnett – February 2008 7 New York Times M. Barnett – February 2008 8 National Geographic Magazine M. Barnett – February 2008 9 National Geographic Magazine M. Barnett – February 2008 10 National Geographic Magazine M. Barnett – February 2008 11 M. Barnett – February 2008 12 M. Barnett – February 2008 13 M. Barnett – February 2008 14 M. Barnett – February 2008 15 M. Barnett – February 2008 16 M. Barnett – February 2008 17 M. Barnett – February 2008 18 M. Barnett – February 2008 19 M. Barnett – February 2008 20 M. Barnett – February 2008 21 M. Barnett – February 2008 22 And on television (shortened version) M. Barnett – February 2008 23 An ATLAS expert explains the Higgs evidence to a layperson. M. Barnett – February 2008 24 US-LHC Student Journalism Program April 2-7, 2008 (overlapping Open Days) Six teams of high school students (3 students/1 teacher) are going to CERN to report on the LHC startup. They will have all major expenses paid. The student/teacher teams will learn about the LHC, ATLAS and CMS experiments by interviewing physicists and engineers and seeing the experiments up close. Teams will act as news reporters to students in their home communities and across the US. These high school journalists will share the excitement with many others via blogs, websites, etc. Each will prepare a video about their visit and the LHC. M. Barnett – February 2008 25 Large Hadron Collider Numbers The biggest most sophisticated detectors ever built Recording the debris from 600 million proton collisions per second requires building gargantuan devices that measure particles with 0.001 cm precision. The most extensive computer system in the world Analyzing the data requires tens of thousands of computers around the world using the Grid. M. Barnett – February 2008 26 ATLAS Experiment Numbers Weight of ATLAS detector A hundred 747 jets (empty) Size of ATLAS detector About half the Notre Dame Cathedral Superconducting wire in magnets Is 122 km (76 miles) long, plus 3000 km (1865 miles) of ordinary cables elsewhere. Data recorded each year 3200 terabytes, equivalent to 7 km (4 miles) of CDROMs stacked on top of each other. Electronic channels About 100 million M. Barnett – February 2008 27 Who builds and operates ATLAS? 2100 scientists from 167 universities and labs in 37 countries 19 M. Barnett – February 2008 28 M. Barnett – February 2008 29 Microscopic Black Hole Event M. Barnett – February 2008 30 Raising the Alarm Google News – Just look under: “CERN black hole” M. Barnett – February 2008 31 Are Microscopic Black Holes Dangerous? Cosmic rays are continuously bombarding Earth's atmosphere with far more energy than protons will have at the LHC, so cosmic rays would produce everything LHC can produce. They have done so throughout the 4.5 billion years of the Earth's existence, and the Earth is still here! The LHC just lets us see these processes in the lab (though at a much lower energy than some cosmic rays). M. Barnett – February 2008 32 − + μ μ How a Higgs boson event might look in ATLAS H → Z Z e− e+ Z → e− e+ Z → μ− μ+ M. Barnett – February 2008 33 New Higgs Event Images M. Barnett – February 2008 34 New Higgs Event Images M. Barnett – February 2008 35 Three Users organizations are going to DC March 12-14 ¾Legislative: Capitol Hill ¾Executive: OMB/OSTP ¾Agencies: DOE and NSF M. Barnett – February 2008 36 M. Barnett – February 2008 37 M. Barnett – February 2008 38 Going to DC M. Barnett – February 2008 39 LHC Physics in Art and Literature M. Barnett – February 2008 40 Extra Dimensions in Art M. Barnett – February 2008 41 Extra Dimensions in Art in art SALVADOR DALI – TO RESEARCH OF THE 4TH DIMENSION (Dora Maar series) M. Barnett – February 2008 42 Extra Dimensions in Literature in literature Narnia M. Barnett – February 2008 43 http://atlas.ch title M. Barnett – February 2008 44 title M. Barnett – February 2008 45 ATLAS Multimedia M. Barnett – February 2008 46 ATLAS on YouTube YouTube.com/TheATLASExperiment 18 videos now. Most viewed has 11,000 viewings. Most have 4.5 of 5 stars ratings M. Barnett – February 2008 47 Hits on ATLAS Website Year Hits 1999 112,694 +++ 2000 183,669 +++++ 2001 287,992 ++++++++ 2002 390,541 ++++++++++ 2003 505,549 +++++++++++++ 2004 519,731 +++++++++++++ 2005 579,186 +++++++++++++++ 2006 911,122 +++++++++++++++++++++++ 2007 1,263,358 ++++++++++++++++++++++++++++++++ M. Barnett – February 2008 48 LHC Schedule M. Barnett – February 2008 49 LHC Schedule M. Barnett – February 2008 50 LHC Commissioning M. Barnett – February 2008 51 LHC Schedule M. Barnett – February 2008 52 LHC Commissioning M. Barnett – February 2008 53 LHC Commissioning M. Barnett – February 2008 54 LHC Commissioning Later stage M. Barnett – February 2008 55 450 GeV Collisions? Will be provided for a limited period only (2/3 shifts, maximum a weekend) during the commissioning for 7 TeV Common view of the experiments: such a run is not required by the experiments. However, collisions at 900 GeV would be useful, mostly for time alignment. A short period with such beam conditions is therefore interesting, provided these beam conditions are safe (no compromise on machine & experiment protection) and stable beam conditions declared. The experiments would not require their magnets to be ON for this short 900 GeV run. M. Barnett – February 2008 56 Maximum Energy ? The general approach is that they only drop from 7 TeV if there is a problem with a magnet (could be a weak dipole or quad causing problems as push toward11,700 A). There are limited gains for machine protection by dropping to 6 TeV, for example. (Factor of two reduction in quench level for an energy reduction of 10% ) Operational procedures will allow to drop from 7 TeV should they need to. M. Barnett – February 2008 57 M. Barnett – February 2008 58 LHC Commissioning All the 182 commissionable SC circuits of S45 were tested A very important first milestone is now achieved Sector45 is commissioned at 5.3TeV with the efforts of many high qualified people in a tough but very friendly environment and now… …let’s continue: Sector56 is at 4K M. Barnett – February 2008 59 ATLAS Critical Path items Pixel Detector – Cables done, Fibers and Cryogenics remain Tile Calorimeter – drawer refurbishment Liquid Argon Cal – Front end boards Magnet system tests Similar issues in CMS M. Barnett – February 2008 60 From M Kotamaki Critical Path (to Closing of Beam Pipe) Feb '08 Mar '08 Apr '08 May '08 Jun '08 56 7 891011 12 1314 15 16 17 18 19 20 2122 23 24 25 26 Finish EO TGC services TGC services JF Close EBA, wheel Side A JD-A and Side A ECT-A SW-A services Small Wheel A Wheel Small LUCID Barrel Calo A electronics repair Pixel A connection & testing closing Barrel Full Magnet tests Barrel T-C hea Pixel C connection & testing closing Barrel Calo C electronics repair ID access to Calo & No SW-C services pipe closed Beam Close EBC, JD-C LUCID Side C and ECT-A Side C TGC Finish EO TGC services JF services C Wheel Small wheel 5 678910111213 14 15 16 1718 19 20 2122 23 24 25 26 Feb '08 Mar '08 Apr '08 May '08 Jun '08 M. Barnett – February 2008 15/02/2008 PJ ATLAS Plenary 61 Conclusions Early Conditions Compared to design conditions • Beam energy likely below 7 TeV. – 6 TeV? – 6.5 TeV? • Fewer protons per bunch • Many fewer bunches • Head-on collisions M. Barnett – February 2008 62 Definitions and Luminosity Design Luminosity L: 33 −2 −1 “Initial” L = 2×10 cm s 34 −2 −1 After three years L = 10 cm s femto = 10−15 pico = 10−12 Assume nano = 10−9 Luminosity L = 1033 cm−2 s−1 1 barn = 10−24 cm2 1 year = 3×107 s (but not all useable) 1033 x 10−24 → 10 fb−1 y−1 (if year = 1×107 s) M. Barnett – February 2008 63 Definitions and Luminosity Assuming L = 1033 cm−2 s−1 1 year → 10 fb−1 1 month → 1 fb−1 1 week → 0.2 fb−1 = 200 pb−1 Initial 2008 run Assuming L = 1031 cm−2 s−1 3 months → 0.03 fb−1 = 30 pb−1 but this is a guess. M. Barnett – February 2008 64 Typical Year M. Barnett – February 2008 65 The First Years? 2007→ 2008 ~ 3 1028 ~ 2 1031 ~ 1 1032 A slide I made in 2005. ~ 4 1032 2008 ~ 2 1033 Works well if you add ~ 7 1032 on one year ~ 2 1033 ~ 5 1033 2009 ~ 5 1033 2010 1034 2011 M. Barnett – February 2008 66 2008 Integrated Luminosity? • Very hard to estimate. • Roughly 30 pb-1 • What physics can be done? 108 events for 30 pb−1 These rates should be multiplied by branching 105 events ratios and efficiencies. for 30 pb−1 100 events for 30 pb−1 LHC M. Barnett – February 2008 67 Some Rates for year 1 and year 2 30 pb-1 (pilot run) 300 pb-1 (year 2?) Channel # of Events # of Events W → µ ν 200,000 2,000,000 Z → µµ 30,000 300,000 t tbar → µ + X 2400 24,000 QCD jets PT>150 GeV 30,000 (for 10% of 300,000 (for 10% of trigger bandwidth) trigger bandwidth) Minimum bias Trigger limited gluino-gluino, M~ 1TeV 30-300 300-3000 Taken from table in hep-ph/0504221 M.
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