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تسجيل مستخدم جديدNew vertex reconstruction algorithms for CMS
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The reconstruction of interaction vertices can be decomposed into a pattern recognition problem (``vertex finding) and a statistical problem (``vertex fitting). We briefly review classical methods. We introduce novel approaches and motivate them in the framework of high-luminosity experiments like at the LHC. We then show comparisons with the classical methods in relevant physics channels
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The PHOBOS experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is studying interactions of heavy nuclei at the largest energies available in the laboratory. The high multiplicity of particles created in heavy io
n collisions makes precise vertex reconstruction possible using information from a spectrometer and a specialized vertex detector with relatively small acceptances. For lower multiplicity events, a large acceptance, single layer multiplicity detector is used and special algorithms are developed to reconstruct the vertex, resulting in high efficiency at the expense of poorer resolution. The algorithms used in the PHOBOS experiment and their performance are presented.
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Starting in the middle of November 2002, the CMS experiment undertook an evaluation of the European DataGrid Project (EDG) middleware using its event simulation programs. A joint CMS-EDG task force performed a stress test by submitting a large number
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