Retired
Dimitris Loukas is head of the Solid-State Detector Instrumentation Laboratory (DIL), working within the Institute of Nuclear and Particle Physics (INPP). He is currently acting as group leader of the INPP CMS group, working for the development, characterization and evaluation of silicon sensors and associated electronics for the upgrade of the CMS Tracker detector foreseen for 2024. His group designed and developed various front-end VLSI circuits for solid state sensors while his research interests include, interaction of radiation with matter, physics of solid-state sensors, read out electronics and data analysis. The group obtained the first ever diagram of x-ray powder diffraction with silicon microstrip sensors. Participation in publications in international scientific journals number more than 90 articles in the subject of radiation detectors and associated electronics as well as more than 900 articles in the subject of the physics of elementary particles, with more than 58k citations. He speaks English and French.
Infrastructure of DIL includes, semiautomatic wire bonder (Delvotec 5430), automatic probe station (Carl Suss PA 150), equipment for electrical characterization of microelectronic devices (HP4092A, Keithley 6517A), climatic chamber (Weiss WKS 3-180/40/5) and various peripheral instruments. The group is involved in the conception, design and development of solid-state sensors and associated electronics since its foundation at the beginning of the 1990s. It was involved in the design and development of silicon microstrip and pixel sensors for the initial phase of the LHC experiments at CERN. In collaboration with the nanoscience institute developed prototypes of silicon sensors for particle physics and x-ray applications along with associated VLSI read out electronics. This joint effort resulted in the design, development and fabrication of strip sensors that are currently installed in the Preshower detector of the CMS experiment at CERN. The contribution to the Preshower project includes the assembly of one quarter of the total number (5200) of the micromodules (assembly of mechanical support, silicon sensor and readout hybrid) as well as the supervision of the production of the total number of hybrids from a Greek company.
Research Interests: I have been doing research mainly in Yang-Mills Field Theory, QCD, physics beyond the standard model and String Theory.
In 1977 I have predicted existence of the chromomagnetic gluon condensation. This discovery was based on the calculation of the effective Lagrangian in Yang-Mills theory, which represents the generalization of the Heisenberg-Euler quantum Lagrangian. The other areas of research includes:
exact solution of renormalization group equations for the effective Lagrangian in Abelian and non-Abelian gauge theories in terms of the beta function and the expression of the intensity of the chromomagnetic gluon condensate to all orders of perturbation theory. The vacuum solutions of Yang-Mills theory have been found in the form of nonlinear plane waves and non-integrability and dynamical stochasticity of these solutions established. The concept of Yang-Mills Classical and Quantum mechanics was introduced.
Application of Ergodic theory to the problem of integrability of classical Yang-Mills equations and demonstration that it is a maximally chaotic dynamical system.
Quantization of relativistic membrane in the light-cone gauge and its duality with the Yang-Mills classical mechanics. Notion of self-dual membrane. I suggested a linear model for QCD string by extending the Feynman path integral to an integral over the surfaces, with the action which is proportional to the linear size of the surface, this is the so called Gonihedric String. This new concept was used in statistical physics to define a new class of Ising type spin systems with the partition function which is a sum over random surfaces with Gonihedric action.
Geometrical nature of the system allows to perform the duality transformation and to find out a new class of gauge spin systems, which are similar to the 3D Ising ferromagnet and Wegner 3D gauge spin systems. In Astrophysics I have been studding N-body problem by means of the Maupertuis principle reducing it to the study of the behavior of the geodesic flow on a Reimannian manifold. Negativity of the corresponding curvature allows to establish the exponential instability of the geodesic trajectories and to compute the relaxation time for the stellar systems like galaxies and globular clusters. That time is substantially smaller than binary, Chandrasekhar relaxation time. In Computational mathematics we have suggested to use maximally chaotic dynamical systems of Kolmogorov-Anosov-Artin type to generate pseudo-random numbers for the Monte-Carlo simulations of physical systems. The concrete realization of the MIXMAX generator has large entropy, is fast and has good spectral properties. The generator was implemented into the main CERN toolkits: Gean4/CLHEP, ROOT and CMS experiment.
Dr Georgios Fanourakis is currently retired Director of Research at the Institute of Nuclear and Particle Physics (INPP) of the National Center for Science Research "Demokritos", Agia Paraskevi (Athens area), Greece.
PhD (1980) on low energy antineutrino interactions with protons (a Brookhaven Bubble chamber experiment) - University-of-Athens/NCSR-Demokritos / Univ-of-Wisconsin-Madison.
Expertise:
Research in experimental Particle Physics since 1975, participating in experiments at Brookhaven National Laboratory (USA), Fermi National Laboratory (USA) and CERN (Europe). He has had significant contributions to the design, construction and operation as well as in data analysis of several experiments and research projects such as: E613 (1978-1983) – neutrinos from charmed meson production, E706 (1983-1993) – direct photon production, D0 (1987-1993) – Fermilab general purpose Collider experiment, NESTOR (2003-2006) - deep sea neutrino telescope tests, DELPHI (1996-2002) – LEP general purpose experiment, CMS (1997-2001) – LHC general purpose experiment, ROSE (1997-2003) – radiation hard silicon detectors, CAST (2001-2015) – search for solar axions, Micromegas detector development (2001-present) for X-ray detection, particle detection and low background physics. Leading and/or contributing to novel Micromegas detector designs and tests (2001-present). Involved in the Electric Dipole Moment of the proton in a storage ring (srEDM) proposal and especially in the design of a Micromegas polarimeter (since 2008). He is a member of the ATLAS LHC general purpose experiment (2017-present). He is currently the Greek group scientific responsible for the ESSnuSB project, involving the design of a high intensity neutrino beam at ESS and a detector setup to measure the CP violation in the leptonic sector (2018- present).
Academic posts - Teaching:
Specialist in Physics (1978-1980) and Research Associate (1980-1983), at the University of Wisconsin, Madison, USA. Research Associate (1983-1985) and Senior Research Associate (1985-1993) at the University of Rochester, USA. Visiting Associate Professor (1993-1996), at the University of Crete, Greece. Principal Researcher (1996-2003), at the Institute of Nuclear Physics of the National Center for Science Research ‘Demokritos’ in Greece (INPP). Director of Research (2003-present), at INPP.
He has taught several University courses (University of Crete, 1993-1996, Hellenic Open University, 2001-2017) and post graduate courses (National Technical University of Athens - Demokritos graduate program, 1997- present) and has delivered numerous lectures to younger students and to the public.
Distinctions etc:
Vice director of INPP (2011-2016). Chairman and/or member of the Scientific Council of INPP (2003-2018). Director of the Education Office of NCSR Demokritos (2013-2018). Chair of the Greek Society for High Energy physics (2009–2010). He has co-authored more than 400 papers in refereed scientific journals and many more in conference proceedings. He is referee in various scientific journals and proposals. He has organized, co-organized or has been a member of the scientific committees of more than 30 scientific and/or educational and outreach International conferences and workshops since 2000.
Dennis Bonatsos received his B.Sc. in Physics at the University of Patras, Greece in 1979 and his Ph.D. in Theoretical Nuclear Physics at the University of Pennsylvania, USA in 1985. He has held positions at the ECT* (Trento, Italy), as well as at the universities of Fribourg (Switzerland), Tuebingen (Germany), Oxford (UK), and Paris XI (Orsay, France). He joined NCSR Demokritos in 1996 as a tenured Senior Researcher and has been a Director of Research since 2002. He has served as a regular member of the Board of Directors of NCSR Demokritos for 8 years, as the Deputy Director of INPP and as the Secretary of the Board of the Nuclear Physics Division of the European Physical Society. He has taught postgraduate courses at the National Technical University of Athens, as well as at the universities of Oxford and Fribourg and has supervised 11 Ph.D. theses (plus 3 ongoing) and 7 M.Sc. theses. He has participated in more than 70 international conferences and schools and he has written 2 books, more than 120 articles in refereed journals, more than 120 articles in international conference proceedings, more than 250 referee reports in more than 30 international journals, has more than 3000 citations and a h-index of 31. Selected recent publications "Advanced Quantum Mechanics", D. Bonatsos (Kostarakis, Athens, 2017). Postgraduate textbook, 470 pages. "Prolate over oblate dominance in deformed nuclei as a consequence of the SU(3) symmetry and the Pauli principle", D. Bonatsos, Letter to the Editor, Eur. Phys. J. A 53 (2017) 148. "Analytic predictions for nuclear shapes, the prolate dominance and the prolate-oblate shape transition in the proxy-SU(3) model", D. Bonatsos, I. E. Assimakis, N. Minkov, A. Martinou, S. Sarantopoulou, R. B. Cakirli, R. F. Casten, and K. Blaum, Phys. Rev. C 95 (2017) 064326. "Proxy-SU(3) symmetry in heavy deformed nuclei", D. Bonatsos, I. E. Assimakis, N. Minkov, A. Martinou, R. B. Cakirli, R. F. Casten, and K. Blaum, Phys. Rev. C 95 (2017) 064325.