Graduate Physics Research Center Building
Position: Assistant Professor
B.Sc. 1991, University of Athens, Greece
M.A., Ph.D., 1998, University of Texas, Austin, TX
Experimental High Energy Physics, Physics beyond the Standard Model, Extra dimensions, Rare Decays, Particle detectors, Scientific computing, GRID technologies.
The particle physics group at Hampton University works at the energy frontier in particle physics with the ATLAS experiment at the CERN Large Hadron Collider (LHC) (http://www.cern.ch and http://atlas.ch). The LHC first began to operate in 2008, and at the end of its first running period in 2009 set a new world record by recording collisions at 2.36 TeV. The LHC provides proton-proton collisions at a center-of-mass energy expected to reach14 TeV. Together, the LHC and ATLAS will open a new window to exciting discoveries about the nature of space, time, and matter. Possibilities include discovery of extra dimensions, creation of mini-black holes, and new particles predicted by the idea of super-symmetry. The physics goals include also the search for the elusive Higgs boson, very high statistics top and bottom quark studies, and searches for evidence of physics beyond the Standard Model, such as super-symmetry, technicolor, or any other signature, as yet imagined or not.
The design and construction of the ATLAS detector was an extremely challenging task. The particle physics group at Hampton University participated in the design, construction and commissioning of one of the tracking detectors in ATLAS detector: the Transition Radiation Tracker (TRT). At present, the group is working in ATLAS detector performance studies, and searches for high momentum di-lepton exotic signatures that could lead to physics discoveries beyond the standard model.
To analyze the data produced by this most complex apparatus, we will use state-of-the-art computing techniques, including multiple CPU clusters of computers and grid distributed computing. A Particle Physics Computing Facility (PPCF) has been built and operated at Hampton University with over 500 CPU cores and 120 TB disk space. It serves as a Tier3 ATLAS computing facility and a simulation computing center.
Dr. Vassilakopoulos is an experimental particle physicist who is working in the ATLAS detector the last decade. He is the Deputy Director of the COSM and he administers and operates the Particle Physics Computing Facility. His most recent research interests focus in the scientific computing and include scalable clustered computer systems, distributed collaborative infrastructure, distributed data management and analysis frameworks, distributed software development useful to High Energy Physics (HEP) experiments and particle accelerators, software project management tools, visualization and software environments appropriate for physics analysis, algorithms and software tools for pattern recognition and optimization of data analysis and tools for improvements to the performance, verification and validation of large software codes, such as found in the LHC experiments.
- Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics.By The ATLAS Collaboration: G. Aad et al.. e-Print: arXiv:0901.0512[hep-ex] (2009).
- The ATLAS Experiment at the CERN Large Hadron Collider. By ATLAS Collaboration: G. Aad et al.. JINST 3:S08003 (2008).
- Combined performance tests before installation of the ATLAS Semiconductor and Transition Radiation Tracking Detectors. E. Abat et al. Aug 2008. JINST 3:P08003 (2008).
- The ATLAS TRT barrel detector. By ATLAS TRT Collaboration (E. Abat et al.). JINST 3:P02014 (2008).
- The ATLAS Transition Radiation Tracker (TRT) proportional drift tube: Design and performance. By ATLAS TRT Collaboration (E. Abat et al.). JINST 3:P02013 (2008).
- ATLAS transition radiation tracker test-beam results. T. Akesson et al., Nucl. Instrum. Meth. A522, 50 (2004).
- X-ray scanner for ATLAS barrel TRT modules. By Taeksu Shin, O.K. Baker, K.W. McFarlane, and Vassilios I. Vassilakopoulos. Proc. 24th International Conf. on Physics in Collision (PIC 2004).
- Recent aging studies for the ATLAS transition radiation tracker. M. Capeans et al., IEEE Trans.Nucl.Sci.51:960-967 (2004).
- An X-ray scanner for wire chambers, By the ATLAS TRT Collaboration: T. Akesson et al., Nucl. Instrum. Meth. A507:622-635 (2003).
- Improved branching ratio measurement for the decay K0(L) --> mu+ mu-. By E871 Collaboration (D. Ambrose et al.). Phys.Rev.Lett.84:1389-1392 (2000).
- New limit on muon and electron lepton number violation from K0(L) --> mu+- e-+ decay. By BNL Collaboration (D. Ambrose et al.). Phys.Rev.Lett.81:5734-5737 (1998).
- A Technique of direct tension measurement of a strung fine wire. By K. Lang, J. Ting, V. Vassilakopoulos, DOE-ER40757-111, Nucl.Instrum.Meth.A420:392-401 (1999).
- First observation of the rare decay mode K0(L) --> e+ e-. By BNL E871 Collaboration (D. Ambrose et al.). Phys.Rev.Lett.81:4309-4312 (1998).