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Resolving astrophysical uncertainties in dark matter direct detection

(2011)

Authors:

Mads T Frandsen, Felix Kahlhoefer, Christopher McCabe, Subir Sarkar, Kai Schmidt-Hoberg
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The effect of the geomagnetic field on cosmic ray energy estimates and large scale anisotropy searches on data from the Pierre Auger Observatory

Journal of Cosmology and Astroparticle Physics 2011:11 (2011)

Authors:

P Abreu, M Aglietta, EJ Ahn, IFM Albuquerque, D Allard, I Allekotte, J Allen, P Allison, J Alvarez Castillo, J Alvarez-Muñiz, M Ambrosio, A Aminaei, L Anchordoqui, S Andringa, T Antičić, A Anzalone, C Aramo, E Arganda, F Arqueros, H Asorey, P Assis, J Aublin, M Ave, M Avenier, G Avila, T Bäcker, M Balzer, KB Barber, AF Barbosa, R Bardenet, SLC Barroso, B Baughman, J Bäuml, JJ Beatty, BR Becker, KH Becker, A Bellétoile, JA Bellido, S BenZvi, C Berat, X Bertou, PL Biermann, P Billoir, F Blanco, M Blanco, C Bleve, H Blümer, M Boháčová, D Boncioli, C Bonifazi, R Bonino, N Borodai, J Brack, P Brogueira, WC Brown, R Bruijn, P Buchholz, A Bueno, RE Burton, KS Caballero-Mora, L Caramete, R Caruso, A Castellina, O Catalano, G Cataldi, L Cazon, R Cester, J Chauvin, SH Cheng, A Chiavassa, JA Chinellato, A Chou, J Chudoba, RW Clay, MR Coluccia, R Conceiçào, F Contreras, H Cook, MJ Cooper, J Coppens, A Cordier, S Coutu, CE Covault, A Creusot, A Criss, J Cronin, A Curutiu, S Dagoret-Campagne, R Dallier, S Dasso, K Daumiller, BR Dawson, RM De Almeida, M De Domenico

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°, detected at the Pierre Auger Observatory. The geomagnetic field induces an azimuthal modulation of the estimated energy of cosmic rays up to the ∼ 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. © 2011 IOP Publishing Ltd and SISSA.
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Brane-Antibrane Backreaction in Axion Monodromy Inflation

ArXiv 1110.6454 (2011)

Abstract:

We calculate the interaction potential between D5 and anti-D5 branes wrapping distant but homologous 2-cycles. The interaction potential is logarithmic in the separation radius and does not decouple at infinity. We show that logarithmic backreaction is generic for 5-branes wrapping distant but homologous 2-cycles, and we argue that this destabilises models of axion monodromy inflation involving NS5 brane-antibrane pairs in separate warped throats towards an uncontrolled region.
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Brane-Antibrane Backreaction in Axion Monodromy Inflation

(2011)
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Observation of anisotropy in the arrival directions of galactic cosmic rays at multiple angular scales with icecube

Astrophysical Journal 740:1 (2011)

Authors:

R Abbasi, Y Abdou, T Abu-Zayyad, J Adams, JA Aguilar, M Ahlers, D Altmann, K Andeen, J Auffenberg, X Bai, M Baker, SW Barwick, R Bay, JL Bazo Alba, K Beattie, JJ Beatty, S Bechet, JK Becker, KH Becker, ML Benabderrahmane, S BenZvi, J Berdermann, P Berghaus, D Berley, E Bernardini, D Bertrand, DZ Besson, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, C Bohm, D Bose, S Böser, O Botner, AM Brown, S Buitink, KS Caballero-Mora, M Carson, D Chirkin, B Christy, J Clem, F Clevermann, S Cohen, C Colnard, DF Cowen, MV D'Agostino, M Danninger, J Daughhetee, JC Davis, C De Clercq, L Demirörs, T Denger, O Depaepe, F Descamps, P Desiati, G De Vries-Uiterweerd, T DeYoung, JC Díaz-Vélez, M Dierckxsens, J Dreyer, JP Dumm, R Ehrlich, J Eisch, RW Ellsworth, O Engdegård, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, MM Foerster, BD Fox, A Franckowiak, R Franke, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Gl̈usenkamp, A Goldschmidt, JA Goodman, D Gora, D Grant, T Griesel, A Groß, S Grullon, M Gurtner, C Ha, A Hajismail, A Hallgren, F Halzen, K Han, K Hanson

Abstract:

Between 2009 May and 2010 May, the IceCube neutrino detector at the South Pole recorded 32 billion muons generated in air showers produced by cosmic rays with a median energy of 20TeV. With a data set of this size, it is possible to probe the southern sky for per-mil anisotropy on all angular scales in the arrival direction distribution of cosmic rays. Applying a power spectrum analysis to the relative intensity map of the cosmic ray flux in the southern hemisphere, we show that the arrival direction distribution is not isotropic, but shows significant structure on several angular scales. In addition to previously reported large-scale structure in the form of a strong dipole and quadrupole, the data show small-scale structure on scales between 15° and 30°. The skymap exhibits several localized regions of significant excess and deficit in cosmic ray intensity. The relative intensity of the smaller-scale structures is about a factor of five weaker than that of the dipole and quadrupole structure. The most significant structure, an excess localized at (right ascension α = 1224 and declination δ = -474), extends over at least 20° in right ascension and has a post-trials significance of 5.3σ. The origin of this anisotropy is still unknown. © 2011. The American Astronomical Society. All rights reserved.
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