Testing astrophysical models for the PAMELA positron excess with cosmic ray nuclei.

Phys Rev Lett 103:8 (2009) 081104

Authors:

Philipp Mertsch, Subir Sarkar

Abstract:

The excess in the positron fraction measured by PAMELA has been interpreted as due to annihilation or decay of dark matter in the Galaxy. More prosaically it has been ascribed to direct production of positrons by nearby pulsars or due to pion production during diffusive shock acceleration of hadronic cosmic rays in nearby sources. We point out that measurements of secondary cosmic ray nuclei can discriminate between these possibilities. New data on the titanium-to-iron ratio support the hadronic source model above and enable a prediction for the boron-to-carbon ratio at energies above 100 GeV.

Does cosmological structure formation require dark energy?

EAS Publications Series 36 (2009) 3-9

Abstract:

Precision measurements of anisotropies in the cosmic microwave background and of the clustering of large-scale structure have supposedly established that the universe is presently dominated by "dark energy" which has negative pressure and behaves similarly to a cosmological constant. This is based on the assumption that the primordial density perturbation has a nearly scale-invariant power-law spectrum and that the dark matter consists of "cold" particles. However there are theoretical and observational indications that the spectrum is not scale-free and it is known that sub-eV mass neutrinos contribute a small component of hot dark matter. This would be sufficient to fit the same observational data without requiring any dark energy. © EAS, EDP Sciences 2009.

The Fluorescence Detector of the Pierre Auger Observatory

ArXiv 0907.4282 (2009)

Authors:

The Pierre Auger Collaboration, J Abraham, P Abreu, M Aglietta, C Aguirre, EJ Ahn, D Allard, I Allekotte, J Allen, P Allison, J Alvarez-Muñiz, M Ambrosio, L Anchordoqui, S Andringa, A Anzalone, C Aramo, E Arganda, S Argirò, K Arisaka, F Arneodo, F Arqueros, T Asch, H Asorey, P Assis, J Aublin, M Ave, G Avila, A Bacher, T Bäcker, D Badagnani, KB Barber, AF Barbosa, HJM Barbosa, N Barenthien, SLC Barroso, B Baughman, P Bauleo, JJ Beatty, T Beau, BR Becker, KH Becker, A Bellétoile, JA Bellido, S BenZvi, C Berat, P Bernardini, X Bertou, PL Biermann, P Billoir, O Blanch-Bigas, F Blanco, C Bleve, H Blümer, M Boháčová, E Bollmann, H Bolz, C Bonifazi, R Bonino, N Borodai, F Bracci, J Brack, P Brogueira, WC Brown, R Bruijn, P Buchholz, A Bueno, RE Burton, NG Busca, KS Caballero-Mora, D CaminL Caramete, R Caruso, W Carvalho, A Castellina, J Castro, O Catalano, L Cazon, R Cester, J Chauvin, A Chiavassa, JA Chinellato, A Chou, J Chudoba, J Chye, PDJ Clark, RW Clay, E Colombo, R Conceição, B Connolly, F Contreras, J Coppens, A Cordero, A Cordier, U Cotti, S Coutu, CE Covault, A Creusot, A Criss, JW Cronin, J Cuautle, A Curutiu, S Dagoret-Campagne, R Dallier, F Daudo, K Daumiller, BR Dawson, RM de Almeida, M De Domenico, C De Donato, SJ de Jong, G De La Vega, WJM de Mello Junior, JRT de Mello Neto, I De Mitri, V de Souza, KD de Vries, G Decerprit, L del Peral, O Deligny, A Della Selva, C Delle Fratte, H Dembinski, C Di Giulio, JC Diaz, PN Diep, C Dobrigkeit, JC D'Olivo, PN Dong, D Dornic, A Dorofeev, JC dos Anjos, MT Dova, D D'Urso, I Dutan, MA DuVernois, R Engel, M Erdmann, CO Escobar, A Etchegoyen, P Facal San Luis, H Falcke, G Farrar, AC Fauth, N Fazzini, F Ferrer, A Ferrero, B Fick, A Filevich, A Filipčič, I Fleck, S Fliescher, R Fonte, CE Fracchiolla, ED Fraenkel, W Fulgione, RF Gamarra, S Gambetta, B García, D García Gámez, D Garcia-Pinto, X Garrido, H Geenen, G Gelmini, H Gemmeke, PL Ghia, U Giaccari, K Gibbs, M Giller, J Gitto, H Glass, LM Goggin, MS Gold, G Golup, F Gomez Albarracin, M Gómez Berisso, PF Gomez Vitale, P Gonçalves, M Gonçalves do Amaral, D Gonzalez, JG Gonzalez, D Góra, A Gorgi, P Gouffon, E Grashorn, V Grassi, S Grebe, M Grigat, AF Grillo, J Grygar, Y Guardincerri, N Guardone, C Guerard, F Guarino, R Gumbsheimer, GP Guedes, J Gutiérrez, JD Hague, V Halenka, P Hansen, D Harari, S Harmsma, S Hartmann, JL Harton, A Haungs, MD Healy, T Hebbeker, G Hebrero, D Heck, C Hojvat, VC Holmes, P Homola, G Hofman, JR Hörandel, A Horneffer, M Horvat, M Hrabovský, H Hucker, T Huege, M Hussain, M Iarlori, A Insolia, F Ionita, A Italiano, S Jiraskova, M Kaducak, KH Kampert, T Karova, P Kasper, B Kégl, B Keilhauer, E Kemp, H Kern, RM Kieckhafer, HO Klages, M Kleifges, J Kleinfeller, R Knapik, J Knapp, D-H Koang, A Kopmann, A Krieger, O Krömer, D Kruppke-Hansen, D Kuempel, N Kunka, A Kusenko, G La Rosa, C Lachaud, BL Lago, P Lautridou, MSAB Leão, D Lebrun, P Lebrun, J Lee, MA Leigui de Oliveira, A Lemiere, A Letessier-Selvon, M Leuthold, I Lhenry-Yvon, R López, A Lopez Agüera, K Louedec, J Lozano Bahilo, A Lucero, H Lyberis, MC Maccarone, C Macolino, S Maldera, M Malek, D Mandat, P Mantsch, F Marchetto, AG Mariazzi, IC Maris, HR Marquez Falcon, D Martello, O Martineau, O Martínez Bravo, HJ Mathes, J Matthews, JAJ Matthews, G Matthiae, D Maurizio, PO Mazur, M McEwen, RR McNeil, G Medina-Tanco, M Melissas, D Melo, E Menichetti, A Menshikov, R Meyhandan, MI Micheletti, G Miele, W Miller, L Miramonti, S Mollerach, M Monasor, D Monnier Ragaigne, F Montanet, B Morales, C Morello, JC Moreno, C Morris, M Mostafá, CA Moura, M Mucchi, S Mueller, MA Muller, R Mussa, G Navarra, JL Navarro, S Navas, P Necesal, L Nellen, F Nerling, C Newman-Holmes, D Newton, PT Nhung, D Nicotra, N Nierstenhoefer, D Nitz, D Nosek, L Nožka, M Nyklicek, J Oehlschläger, A Olinto, P Oliva, VM Olmos-Gilbaja, M Ortiz, F Ortolani, B Oßwald, N Pacheco, D Pakk Selmi-Dei, M Palatka, J Pallotta, G Parente, E Parizot, S Parlati, S Pastor, M Patel, T Paul, V Pavlidou, K Payet, M Pech, J Pȩkala, IM Pepe, L Perrone, R Pesce, E Petermann, S Petrera, P Petrinca, A Petrolini, Y Petrov, J Petrovic, C Pfendner, A Pichel, R Piegaia, T Pierog, M Pimenta, T Pinto, V Pirronello, O Pisanti, M Platino, J Pochon, VH Ponce, M Pontz, J Pouryamout, L Prado Jr, P Privitera, M Prouza, EJ Quel, G Raia J Rautenberg, O Ravel, D Ravignani, A Redondo, HC Reis, S Reucroft, B Revenu, FAS Rezende, J Ridky, S Riggi, M Risse, C Rivière, V Rizi, C Robledo, MD Roberts, G Rodriguez, J Rodriguez Martino, J Rodriguez Rojo, I Rodriguez-Cabo, MD Rodríguez-Frías, G Ros, J Rosado, T Rossler, M Roth, B Rouillé-d'Orfeuil, E Roulet, AC Rovero, F Salamida, H Salazar b, G Salina, F Sánchez, M Santander, CE Santo, EM Santos, F Sarazin, S Sarkar, R Sato, N Scharf, V Scherini, H Schieler, P Schiffer, G Schleif A Schmidt, F Schmidt, T Schmidt, O Scholten, H Schoorlemmer, J Schovancova, P Schovánek, F Schroeder, S Schulte, F Schüssler, D Schuster, SJ Sciutto, M Scuderi, A Segreto, D Semikoz, G Sequieros, M Settimo, RC Shellard, I Sidelnik, BB Siffert, A Smiałkowski, R Šmída, AGK Smith, BE Smith, GR Snow, P Sommers, J Sorokin, H Spinka, R Squartini, E Strazzeri, A Stutz, F Suarez, T Suomijärvi, AD Supanitsky, MS Sutherland, J Swain, Z Szadkowski, A Tamashiro, A Tamburro, T Tarutina, O Taşcău, R Tcaciuc, D Tcherniakhovski, NT Thao, D Thomas, R Ticona, J Tiffenberg, C Timmermans, W Tkaczyk, CJ Todero Peixoto, B Tomé, A Tonachini, I Torres, P Trapani, P Travnicek, DB Tridapalli, G Tristram, E Trovato, V Tuci, M Tueros, E Tusi, R Ulrich, M Unger, M Urban, JF Valdés Galicia, I Valiño, L Valore, AM van den Berg, JR Vázquez, RA Vázquez, D Veberič, A Velarde, T Venters, V Verzi, M Videla, L Villaseñor, G Vitali, S Vorobiov, L Voyvodic, H Wahlberg, P Wahrlich, O Wainberg, D Warner, S Westerhoff, BJ Whelan, N Wild, C Wiebusch, G Wieczorek, L Wiencke, B Wilczyńska, H Wilczyński, C Wileman, MG Winnick, G Wörner, H Wu, B Wundheiler, T Yamamoto, P Younk, G Yuan, A Yushkov, E Zas, D Zavrtanik, M Zavrtanik, I Zaw, A Zepeda b, M Ziolkowski

Abstract:

The Pierre Auger Observatory is a hybrid detector for ultra-high energy cosmic rays. It combines a surface array to measure secondary particles at ground level together with a fluorescence detector to measure the development of air showers in the atmosphere above the array. The fluorescence detector comprises 24 large telescopes specialized for measuring the nitrogen fluorescence caused by charged particles of cosmic ray air showers. In this paper we describe the components of the fluorescence detector including its optical system, the design of the camera, the electronics, and the systems for relative and absolute calibration. We also discuss the operation and the monitoring of the detector. Finally, we evaluate the detector performance and precision of shower reconstructions.

Atmospheric effects on extensive air showers observed with the Surface Detector of the Pierre Auger Observatory

ArXiv 0906.5497 (2009)

Abstract:

Atmospheric parameters, such as pressure (P), temperature (T) and density, affect the development of extensive air showers initiated by energetic cosmic rays. We have studied the impact of atmospheric variations on extensive air showers by means of the surface detector of the Pierre Auger Observatory. The rate of events shows a ~10% seasonal modulation and ~2% diurnal one. We find that the observed behaviour is explained by a model including the effects associated with the variations of pressure and density. The former affects the longitudinal development of air showers while the latter influences the Moliere radius and hence the lateral distribution of the shower particles. The model is validated with full simulations of extensive air showers using atmospheric profiles measured at the site of the Pierre Auger Observatory.

Astrophysical Sources of Cosmic Rays and Related Measurements with the Pierre Auger Observatory

ArXiv 0906.2347 (2009)

Authors:

The Pierre Auger Collaboration, J Abraham, P Abreu, M Aglietta, C Aguirre, EJ Ahn, D Allard, I Allekotte, J Allen, J Alvarez-Muñiz, M Ambrosio, L Anchordoqui, S Andringa, A Anzalone, C Aramo, E Arganda, S Argirò, K Arisaka, F Arneodo, F Arqueros, T Asch, H Asorey, P Assis, J Aublin, M Ave, G Avila, T Bäcker, D Badagnani, KB Barber, AF Barbosa, SLC Barroso, B Baughman, P Bauleo, JJ Beatty, T Beau, BR Becker, KH Becker, A Bellétoile, JA Bellido, S BenZvi, C Berat, P Bernardini, X Bertou, PL Biermann, P Billoir, O Blanch-Bigas, F 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, NG Busca, KS Caballero-Mora, L Caramete, R Caruso, W Carvalho, A Castellina, O Catalano, L Cazon, R Cester, J Chauvin, A Chiavassa, JA Chinellato, A Chou, J Chudoba, J Chye, RW Clay, E Colombo, R Conceição, B Connolly, F Contreras, J Coppens, A Cordier, U Cotti, S Coutu, CE Covault, A Creusot, A Criss, J Cronin, A Curutiu, S Dagoret-Campagne, R Dallier, K Daumiller, BR Dawson, RM de Almeida, M De Domenico, C De Donato, SJ de Jong, G De La Vega, WJM de Mello Junior, JRT de Mello Neto, I De Mitri, V de Souza, KD de Vries, G Decerprit, L del Peral, O Deligny, A Della Selva, C Delle Fratte, H Dembinski, C DiGiulio, JC Diaz, PN Diep, C Dobrigkeit, JC D'Olivo, PN Dong, A Dorofeev, JC dos Anjos, MT Dova, D D'Urso, I Dutan, MA DuVernois, R Engel, M Erdmann, CO Escobar, A Etchegoyen, P Facal San Luis, H Falcke, G Farrar, AC Fauth, N Fazzini, F Ferrer, A Ferrero, B Fick, A Filevich, A Filipčič, I Fleck, S Fliescher, CE Fracchiolla, ED Fraenkel, W Fulgione, RF Gamarra, S Gambetta, B García, D GarcíaGámez, D Garcia-Pinto, X Garrido, G Gelmini, H Gemmeke, PL Ghia, U Giaccari, M Giller, H Glass, LM Goggin, MS Gold, G Golup, F Gomez Albarracin, M Gómez Berisso, P Gonçalves, M Gonçalves do Amaral, D Gonzalez, JG Gonzalez, D Góra, A Gorgi, P Gouffon, SR Gozzini, E Grashorn, S Grebe, M Grigat, AF Grillo, Y Guardincerri, F Guarino, GP Guedes, J Gutiérrez, JD Hague, V Halenka, P Hansen, D Harari, S Harmsma, JL Harton, A Haungs, MD Healy, T Hebbeker, G Hebrero, D Heck, VC Holmes, P Homola, JR Hörandel, A Horneffer, M Hrabovský, T Huege, M Hussain, M Iarlori, A Insolia, F Ionita, A Italiano, S Jiraskova, M Kaducak, KH Kampert, T Karova, P Kasper, B Kégl, B Keilhauer, E Kemp, RM Kieckhafer, HO Klages, M Kleifges, J Kleinfeller, R Knapik, J Knapp, D-H Koang, A Krieger, O Krömer, D Kruppke-Hansen, F Kuehn, D Kuempel, K Kulbartz, N Kunka, A Kusenko, G LaRosa, C Lachaud, BL Lago, P Lautridou, MSAB Leão, D Lebrun, P Lebrun, J Lee, MA Leigui de Oliveira, A Lemiere, A Letessier-Selvon, M Leuthold, I Lhenry-Yvon, R López, A Lopez Agüera, K Louedec, J Lozano Bahilo, A Lucero, H Lyberis, MC Maccarone, C Macolino, S Maldera, D Mandat, P Mantsch, AG Mariazzi, IC Maris, HR Marquez Falcon, D Martello, O Martínez Bravo, HJ Mathes, J Matthews, JAJ Matthews, G Matthiae, D Maurizio, PO Mazur, M McEwen, RR McNeil, G Medina-Tanco, M Melissas, D Melo, E Menichetti, A Menshikov, R Meyhandan, MI Micheletti, G Miele, W Miller, L Miramonti, S Mollerach, M Monasor, D Monnier Ragaigne, F Montanet, B Morales, C Morello, JC Moreno, C Morris, M Mostafá, CA Moura, S Mueller, MA Muller, R Mussa, G Navarra, JL Navarro, S Navas, P Necesal, L Nellen, C Newman-Holmes, D Newton, PT Nhung, N Nierstenhoefer, D Nitz, D Nosek, L Nožka, M Nyklicek, J Oehlschläger, A Olinto, P Oliva, VM Olmos-Gilbaja, M Ortiz, N Pacheco, D Pakk Selmi-Dei, M Palatka, J Pallotta, G Parente, E Parizot, S Parlati, S Pastor, M Patel, T Paul, V Pavlidou, K Payet, M Pech, J Pȩkala, IM Pepe, L Perrone, R Pesce, E Petermann, S Petrera, P Petrinca, A Petrolini, Y Petrov, J Petrovic, C Pfendner, R Piegaia, T Pierog, M Pimenta, T Pinto, V Pirronello, O Pisanti, M Platino, J Pochon, VH Ponce, M Pontz, P Privitera, M Prouza, EJ Quel, J Rautenberg, O Ravel, D Ravignani, A Redondo, B Revenu, FAS Rezende, J Ridky, S Riggi, M Risse, C Rivière, V Rizi, C Robledo, G Rodriguez, J Rodriguez Martino, J Rodriguez Rojo, I Rodriguez-Cabo, MD Rodríguez-Frías, G Ros, J Rosado, T Rossler, M Roth, B Rouillé-d'Orfeuil, E Roulet, AC Rovero, F Salamida, H Salazar, G Salina, F Sánchez, M Santander, CE Santo, EM Santos, F Sarazin, S Sarkar, R Sato, N Scharf, V Scherini, H Schieler, P Schiffer, A Schmidt, F Schmidt, T Schmidt, O Scholten, H Schoorlemmer, J Schovancova, P Schovánek, F Schroeder, S Schulte, F Schüssler, D Schuster, SJ Sciutto, M Scuderi, A Segreto, D Semikoz, M Settimo, RC Shellard, I Sidelnik, BB Siffert, G Sigl, A Śmiałkowski, R Šmída, BE Smith, GR Snow, P Sommers, J Sorokin, H Spinka, R Squartini, E Strazzeri, A Stutz, F Suarez, T Suomijärvi, AD Supanitsky, MS Sutherland, J Swain, Z Szadkowski, A Tamashiro, A Tamburro, T Tarutina, O Taşcău, R Tcaciuc, D Tcherniakhovski, D Tegolo, NT Thao, D Thomas, R Ticona, J Tiffenberg, C Timmermans, W Tkaczyk, CJ Todero Peixoto, B Tomé, A Tonachini, I Torres, P Travnicek, DB Tridapalli, G Tristram, E Trovato, M Tueros, R Ulrich, M Unger, M Urban, JF Valdés Galicia, I Valiño, L Valore, AM vandenBerg, JR Vázquez, RA Vázquez, D Veberič, A Velarde, T Venters, V Verzi, M Videla, L Villaseñor, S Vorobiov, L Voyvodic, H Wahlberg, P Wahrlich, O Wainberg, D Warner, AA Watson, S Westerhoff, BJ Whelan, G Wieczorek, L Wiencke, B Wilczyńska, H Wilczyński, C Wileman, MG Winnick, H Wu, B Wundheiler, T Yamamoto, P Younk, G Yuan, A Yushkov, E Zas, D Zavrtanik, M Zavrtanik, I Zaw, A Zepeda, M Ziolkowski

Abstract:

Studies of the correlations of ultra-high energy cosmic ray directions with extra-Galactic objects, of general anisotropy, of photons and neutrinos, and of other astrophysical effects, with the Pierre Auger Observatory. Contributions to the 31st ICRC, Lodz, Poland, July 2009.