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Agarwalla, S. K., Blennow, M., Fernandez-Martinez, E., & Mena, O. (2011). Neutrino probes of the nature of light dark matter. J. Cosmol. Astropart. Phys., 09(9), 004–19pp.
Abstract: Dark matter particles gravitationally trapped inside the Sun may annihilate into Standard Model particles, producing a flux of neutrinos. The prospects of detecting these neutrinos in future multi-kt neutrino detectors designed for other physics searches are explored here. We study the capabilities of a 34/100 kt liquid argon detector and a 100 kt magnetized iron calorimeter detector. These detectors are expected to determine the energy and the direction of the incoming neutrino with unprecedented precision allowing for tests of the dark matter nature at very low dark matter masses, in the range of 10-25 GeV. By suppressing the atmospheric background with angular cuts, these techniques would be sensitive to dark matter-nucleon spin-dependent cross sections at the fb level, reaching down to a few ab for the most favorable annihilation channels and detector technology.
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Pierre Auger Collaboration(Abreu, P. et al), & Pastor, S. (2011). The effect of the geomagnetic field on cosmic ray energy estimates and large scale anisotropy searches on data from the Pierre Auger Observatory. J. Cosmol. Astropart. Phys., 11(11), 022.
Abstract: We present a comprehensive study of the influence of the geomagnetic field on the energy estimation of extensive air showers with a zenith angle smaller than 60 degrees, detected at the Pierre Auger Observatory. the geomagnetic field induces an azimuthal modulation of the estimated energy of cosmic rays up to the similar to 2% level at large zenith angles. We present a method to account for this modulation of the reconstructed energy. We analyse the effect of the modulation on large scale anisotropy searches in the arrival direction distributions of cosmic rays. At a given energy, the geomagnetic effect is shown to induce a pseudo-dipolar pattern at the percent level in the declination distribution that needs to be accounted for.
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Semikoz, V. B., & Valle, J. W. F. (2011). Chern-Simons anomaly as polarization effect. J. Cosmol. Astropart. Phys., 11(11), 048.
Abstract: The parity violating, Chern-Simons term in the epoch before the electroweak phase transition can be interpreted as a polarization effect associated to massless right-handed electrons (positrons) in the presence of a large-scale seed hypermagnetic field. We reconfirm the viability of a unified seed field scenario relating the cosmological baryon asymmetry and the origin of the protogalactic large-scale magnetic fields observed in astronomy.
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Bertone, G., Cerdeño, D. G., Fornasa, M., Ruiz de Austri, R., Strege, C., & Trotta, R. (2012). Global fits of the cMSSM including the first LHC and XENON100 data. J. Cosmol. Astropart. Phys., 01(1), 015–23pp.
Abstract: We present updated global fits of the constrained Minimal Supersymmetric Standard Model (cMSSM), including the most recent constraints from the ATLAS and CMS detectors at the LHC, as well as the most recent results of the XENON100 experiment. Our robust analysis takes into account both astrophysical and hadronic uncertainties that enter in the calculation of the rate of WIMP-induced recoils in direct detection experiment. We study the consequences for neutralino Dark Matter, and show that current direct detection data already allow to robustly rule out the so-called Focus Point region, therefore demonstrating the importance of particle astrophysics experiments in constraining extensions of the Standard Model of Particle Physics. We also observe an increased compatibility between results obtained from a Bayesian and a Frequentist statistical perspective. We find that upcoming ton-scale direct detection experiments will probe essentially the entire currently favoured region (at the 99% level), almost independently of the statistical approach used. Prospects for indirect detection of the cMSSM are further reduced.
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Bertone, G., Cumberbatch, D., Ruiz de Austri, R., & Trotta, R. (2012). Dark Matter searches: the nightmare scenario. J. Cosmol. Astropart. Phys., 01(1), 004–24pp.
Abstract: The unfortunate case where the Large Hadron Collider (LHC) fails to discover physics Beyond the Standard Model (BSM) is sometimes referred to as the “Nightmare scenario” of particle physics. We study the consequences of this hypothetical scenario for Dark Matter (DM), in the framework of the constrained Minimal Supersymmetric Standard Model (cMSSM). We evaluate the surviving regions of the cMSSM parameter space after null searches at the LHC, using several different LHC configurations, and study the consequences for DM searches with ton-scale direct detectors and the IceCube neutrino telescope. We demonstrate that ton-scale direct detection experiments will be able to conclusively probe the cMSSM parameter space that would survive null searches at the LHC with 100 fb(-1) of integrated luminosity at 14TeV. We also demonstrate that IceCube (80 strings plus DeepCore) will be able to probe as much as similar or equal to 17% of the currently favoured parameter space after 5 years of observation.
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