Particle Data Group(Nakamura, K. et al), & Hernandez-Rey, J. J. (2010). Review of Particle Physics. J. Phys. G, 37(7a), 1–1422.
Abstract: This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2158 new measurements from 551 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. Among the 108 reviews are many that are new or heavily revised including those on neutrino mass, mixing, and oscillations, QCD, top quark, CKM quark-mixing matrix, V-ud & V-us, V-cb & V-ub, fragmentation functions, particle detectors for accelerator and non-accelerator physics, magnetic monopoles, cosmological parameters, and big bang cosmology. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.1b1.gov.
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Barenboim, G., & Panotopoulos, G. (2010). Gravitino dark matter in the constrained next-to-minimal supersymmetric standard model with neutralino next-to-lightest superpartner. J. High Energy Phys., 09, 011–20pp.
Abstract: The viability of a possible cosmological scenario is investigated. The theoretical framework is the constrained next-to-minimal supersymmetric standard model (cNMSSM), with a gravitino playing the role of the lightest supersymmetric particle (LSP) and a neutralino acting as the next-to-lightest supersymmetric particle (NLSP). All the necessary constraints from colliders and cosmology have been taken into account. For gravitino we have considered the two usual production mechanisms, namely out-of equillibrium decay from the NLSP, and scattering processes from the thermal bath. The maximum allowed reheating temperature after inflation, as well as the maximum allowed gravitino mass are determined.
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ATLAS Collaboration(Adragna, P. et al), Castelo, J., Castillo Gimenez, V., Cuenca, C., Ferrer, A., Fullana, E., et al. (2010). Measurement of pion and proton response and longitudinal shower profiles up to 20 nuclear interaction lengths with the ATLAS Tile calorimeter. Nucl. Instrum. Methods Phys. Res. A, 615(2), 158–181.
Abstract: The response of pions and protons in the energy range of 20-180 GeV, produced at CERN's SPS H8 test-beam line in the ATLAS iron-scintillator Tile hadron calorimeter, has been measured. The test-beam configuration allowed the measurement of the longitudinal shower development for pions and protons up to 20 nuclear interaction lengths. It was found that pions penetrate deeper in the calorimeter than protons. However, protons induce showers that are wider laterally to the direction of the impinging particle. Including the measured total energy response, the pion-to-proton energy ratio and the resolution, all observations are consistent with a higher electromagnetic energy fraction in pion-induced showers. The data are compared with GEANT4 simulations using several hadronic physics lists. The measured longitudinal shower profiles are described by an analytical shower parametrization within an accuracy of 5-10%. The amount of energy leaking out behind the calorimeter is determined and parametrized as a function of the beam energy and the calorimeter depth. This allows for a leakage correction of test-beam results in the standard projective geometry.
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AGATA Collaboration, Doncel, M., Recchia, F., Quintana, B., Gadea, A., & Farnea, E. (2010). Experimental test of the background rejection, through imaging capability, of a highly segmented AGATA germanium detector. Nucl. Instrum. Methods Phys. Res. A, 622(3), 614–618.
Abstract: The development of highly segmented germanium detectors as well as the algorithms to identify the position of the interaction within the crystal opens the possibility to locate the gamma-ray source using Compton imaging algorithms. While the Compton-suppression shield, coupled to the germanium detector in conventional arrays, works also as an active filter against the gamma rays originated outside the target, the new generation of position sensitive gamma-ray detector arrays has to fully rely on tracking capabilities for this purpose. In specific experimental conditions, as the ones foreseen at radioactive beam facilities, the ability to discriminate background radiation improves the sensitivity of the gamma spectrometer. In this work we present the results of a measurement performed at the Laboratori Nazionali di Legnaro (LNL) aiming the evaluation of the AGATA detector capabilities to discriminate the origin of the gamma rays on an event-by-event basis. It will be shown that, exploiting the Compton scattering formula, it is possible to track back gamma rays coming from different positions, assigning them to specific emitting locations. These imaging capabilities are quantified for a single crystal AGATA detector.
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Blanes, S., Casas, F., Oteo, J. A., & Ros, J. (2010). A pedagogical approach to the Magnus expansion. Eur. J. Phys., 31(4), 907–918.
Abstract: Time-dependent perturbation theory as a tool to compute approximate solutions of the Schrodinger equation does not preserve unitarity. Here we present, in a simple way, how the Magnus expansion (also known as exponential perturbation theory) provides such unitary approximate solutions. The purpose is to illustrate the importance and consequences of such a property. We suggest that the Magnus expansion may be introduced to students in advanced courses of quantum mechanics.
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Yamagata-Sekihara, J., Cabrera, D., Vicente Vacas, M. J., & Hirenzaki, S. (2010). Formation of phi Mesic Nuclei. Prog. Theor. Phys., 124(1), 147–162.
Abstract: We consider the structure and formation of the phi mesic nuclei to investigate the experimental feasibility of the observation of signals of the phi mesic nucleus formation. phi mesic nuclei are considered to be very important objects to study the in-medium modification of the phi-meson spectral function at finite density. We consider ((p) over bar, phi), (gamma, p) and (pi(-), n) reactions to produce a phi-meson inside the nucleus and evaluate the effects of its medium modifications to the reaction cross sections. We also estimate the consequences of the uncertainties of the in-medium (K) over bar self-energy to the phi-nucleus interaction. We find that it may be possible to see peak structures in the reaction spectra for the strong attractive potential cases. On the other hand, for strong absorptive interaction cases with relatively weak attraction, it is very difficult to observe clear peaks and we may need to know the spectrum shape in a wide energy region to deduce the properties of phi.
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AGATA Collaboration, Farnea, E., Recchia, F., Bazzacco, D., Kroll, T., Podolyak, Z., et al. (2010). Conceptual design and Monte Carlo simulations of the AGATA array. Nucl. Instrum. Methods Phys. Res. A, 621(1-3), 331–343.
Abstract: The aim of the Advanced GAmma Tracking Array (AGATA) project is the construction of an array based on the novel concepts of pulse shape analysis and gamma-ray tracking with highly segmented Ge semiconductor detectors. The conceptual design of AGATA and its performance evaluation under different experimental conditions has required the development of a suitable Monte Carlo code. In this article, the description of the code as well as simulation results relevant for AGATA, are presented.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Measurement of d sigma/dy of Drell-Yan e(+)e(-) pairs in the Z mass region from p(p)over-bar collisions at root s=1.96 TeV. Phys. Lett. B, 692(4), 232–239.
Abstract: We report on a CDF measurement of the total cross section and rapidity distribution, d sigma/dy, for gamma*/Z -> e(+)e(-) events in the Z boson mass region (66 < M-ee < 116 GeV/c(2)) produced in p (p) over bar collisions at root s = 1.96 TeV with 2.1 fb(-1) of integrated luminosity. The measured cross section of 257 +/- 16 pb and d sigma/dy distribution are compared with Next-to-Leading-Order (NLO) and Next-to-Next-to-Leading-Order (NNLO) QCD theory predictions with CTEQ and MRST/MSTW parton distribution functions (PDFs). There is good agreement between the experimental total cross section and d sigma/dy measurements with theoretical calculations with the most recent NNLO PDFs.
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Llosa, G., Barrio, J., Lacasta, C., Bisogni, M. G., Del Guerra, A., Marcatili, S., et al. (2010). Characterization of a PET detector head based on continuous LYSO crystals and monolithic, 64-pixel silicon photomultiplier matrices. Phys. Med. Biol., 55(23), 7299–7315.
Abstract: The characterization of a PET detector head based on continuous LYSO crystals and silicon photomultiplier (SiPM) arrays as photodetectors has been carried out for its use in the development of a small animal PET prototype. The detector heads are composed of a continuous crystal and a SiPM matrix with 64 pixels in a common substrate, fabricated specifically for this project. Three crystals of 12 mm x 12 mm x 5 mm size with different types of painting have been tested: white, black and black on the sides but white on the back of the crystal. The best energy resolution, obtained with the white crystal, is 16% FWHM. The detector response is linear up to 1275 keV. Tests with different position determination algorithms have been carried out with the three crystals. The spatial resolution obtained with the center of gravity algorithm is around 0.9 mm FWHM for the three crystals. As expected, the use of this algorithm results in the displacement of the reconstructed position toward the center of the crystal, more pronounced in the case of the white crystal. A maximum likelihood algorithm has been tested that can reconstruct correctly the interaction position of the photons also in the case of the white crystal.
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ANTARES Collaboration(Aguilar, J. A. et al), Bigongiari, C., Dornic, D., Emanuele, U., Gomez-Gonzalez, J. P., Hernandez-Rey, J. J., et al. (2010). Performance of the front-end electronics of the ANTARES neutrino telescope. Nucl. Instrum. Methods Phys. Res. A, 622(1), 59–73.
Abstract: ANTARES is a high-energy neutrino telescope installed in the Mediterranean Sea at a depth of 2475 m. It consists of a three-dimensional array of optical modules, each containing a large photomultiplier tube. A total of 2700 front-end ASICs named analogue ring samplers (ARS) process the phototube signals, measure their arrival time, amplitude and shape as well as perform monitoring and calibration tasks. The ARS chip processes the analogue signals from the optical modules and converts information into digital data. All the information is transmitted to shore through further multiplexing electronics and an optical link. This paper describes the performance of the ARS chip: results from the functionality and characterization tests in the laboratory are summarized and the long-term performance in the apparatus is illustrated.
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