Comparison of the moments of the X(max) distribution predicted by different cosmic ray shower simulation models

In this paper we study the depth at which a cosmic ray shower reaches its maximum (Xmax) as predicted by Monte Carlo simulation. The use of Xmax in the determination of the primary particle mass can only be done by comparing the measured values with simulation predictions. For this reason it is important to study the differences between the available simulation models. We have done a study of the first and second moments of the X max distribution using the Corsika and Conex programs. The study was done with high statistics in the energy range from 1017 to 10 20.4 eV. We focus our analysis in the different implementations of the hadronic interaction models Sibyll2.1 and QGSJetII in Corsika and Conex. We show that the predictions of the «Xmax» and RMS(X max) depend slightly on the combination of simulation program and hadronic interaction model. Although these differences are small, they are not negligible in some cases (up to 5 g/cm2 for the worse case) and they should be considered as a systematic uncertainty of the model predictions for «Xmax» and RMS(Xmax). We have included a table with the suggested systematic uncertainties for the model predictions. Finally, we present a parametrization of the Xmax distribution as a function of mass and energy according to the models Sibyll2.1 and QGSJetII, and showed an example of its application to obtain the predicted Xmax distributions from cosmic ray propagation models. © 2013 Elsevier B.V. All rights reserved.Carlos Jose Todero Peixoto, Vitor de Souza, Jose Alfredo Bellid

Nuclear Physics Meets the Sources of the Ultra-High Energy Cosmic Rays

The determination of the injection composition of cosmic ray nuclei within astrophysical sources requires sufficiently accurate descriptions of the source physics and the propagation - apart from controlling astrophysical uncertainties. We therefore study the implications of nuclear data and models for cosmic ray astrophysics, which involves the photo-disintegration of nuclei up to iron in astrophysical environments. We demonstrate that the impact of nuclear model uncertainties is potentially larger in environments with non-thermal radiation fields than in the cosmic microwave background. We also study the impact of nuclear models on the nuclear cascade in a gamma-ray burst radiation field, simulated at a level of complexity comparable to the most precise cosmic ray propagation code. We conclude with an isotope chart describing which information is in principle necessary to describe nuclear interactions in cosmic ray sources and propagation.Comment: 11 pages, 6 figures. Publication is open acces

Uno studio sulla massima deflessione degli ultra-high-energy cosmic rays da parte dei campi magnetici primordiali

Gli Ultra-High-Energy Cosmic Rays sono dei raggi cosmici-dotati di energia estremamente elevata-che raggiungono la Terra con un bassissimo rateo e dei quali abbiamo pochi dati a riguardo; le incertezze riguardano la loro composizione, la loro sorgente, i metodi di accelerazione e le caratteristiche dei campi magnetici che li deviano durante il loro cammino. L’obiettivo di questo studio è determinare quali modelli di campo magnetico possano descrivere correttamente la propagazione degli UHECRs, andando a fare un confronto con i dati sperimentali a disposizione; infatti, quello che osserviamo è una distribuzione isotropa nel cielo e, di conseguenza, i modelli teorici di propagazione, per poter essere accettati, devono rispecchiare tale comportamento. Sono stati testati nove modelli di campo magnetico tratti da simulazioni cosmologiche, andando a considerare due diverse composizione per i CRs (simil-ferro e simil-protone) e il risultato ha dato delle risposte positive solo per tre di essi. Tali modelli, per cui troviamo accordo, sono caratterizzati da una scala di inomegeneità più ampia rispetto a quella dei modelli scartati, infatti, analizzando il loro spettro di potenza, il maggior contributo è dato da fluttuazioni di campo magnetico su scale di 10 Mpc. Ciò naturalmente, viste anche le poche informazioni riguardo ai campi magnetici intergalattici, ci porta a pensare che campi di questo tipo siano favoriti. Inoltre, per tali modelli, gli esiti sono risultati particolarmente in accordo con i dati sperimentali, considerando CRs con composizione simile al ferro: ciò fa pensare che tale composizione possa essere quella effettiva

The upgrade of the Pierre Auger Observatory: AugerPrime

Over the last 15 years the Pierre Auger Observatory has accumulated the world’s largest exposure to ultrahigh-energy cosmic rays (UHECRs) and the analysis of this dataset led to major advances in our understanding of the nature of UHECRs. The new perspectives opened by the current results call for an upgrade of the Observatory (dubbed AugerPrime), whose main aim is the collection of new information about the primary mass of UHECRs, mandatory to interpret all the observations into a unified picture. The upgrade program includes: the installation of a plastic scintillator detector on top of each water-Cherenkov detector (WCD) of the surface array; the addition of a small photomultiplier tube in each WCD to extend the dynamic range of measurement; an array of underground scintillator detectors to measure the muonic component of extensive air showers; the deployment of a radio antenna atop each WCD; and new electronics to process the signals from all the detectors. An overview of the upgrade is provided, together with the expected performances and the improved physics sensitivity

FRAM telescopes and their measurements of aerosol content at the Pierre Auger Observatory and at future sites of the Cherenkov Telescope Array

open391siA FRAM (F/(Ph)otometric Robotic Atmospheric Monitor) telescope is a system of a robotic mount, a large-format CCD camera and a fast telephoto lens that can be used for atmospheric monitoring at any site when information about the atmospheric transparency is required with high spatial or temporal resolution and where continuous use of laser-based methods for this purpose would interfere with other observations. The original FRAM has been operated at the Pierre Auger Observatory in Argentina for more than a decade, while three more FRAMs are foreseen to be used by the Cherenkov Telescope Array (CTA). The CTA FRAMs are being deployed ahead of time to characterize the properties of the sites prior to the operation of the CTA telescopes; one FRAM has been running on the planned future CTA site in Chile for a year while two others are expected to become operational before the end of 2018. We report on the hardware and current status of operation and/or deployment of all the FRAM instruments in question as well as on some of the preliminary results of integral aerosol measurements by the FRAMs in Argentina and Chile.openJaneček, P.; Aab, A.; Abreu, P.; Aglietta, M.; Albuquerque, I.F.M.; Albury, J.M.; Allekotte, I.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Anastasi, G.A.; Anchordoqui, L.; Andrada, B.; Andringa, S.; Aramo, C.; Asorey, H.; Assis, P.; Avila, G.; Badescu, A.M.; Balaceanu, A.; Barbato, F.; Barreira Luz, R.J.; Baur, S.; Becker, K.H.; Bellido, J.A.; Berat, C.; Bertaina, M.E.; Bertou, X.; Bierman, P.L.; Biteau, J.; Blaess, S.G.; Blanco, A.; Blazek, J.; Bleve, C.; Boháčová, M.; Bonifazi, C.; Borodai, N.; Botti, A.M.; Brac, J.; Bretz, T.; Bridgeman, A.; Briechle, F.L.; Buchholz, P.; Bueno, A.; Buitink, S.; Buscemi, M.; Caballero-Mora, K.S.; Caccianiga, L.; Calcagni, L.; Cancio, A.; Canfora, F.; Carceller, J.M.; Caruso, R.; Castellina, A.; Catalani, F.; Cataldi, G.; Cazon, L.; Chinellato, J.A.; Chudoba, J.; Chytka, L.; Clay, R.W.; Cobos Cerutti, A.C.; Colalillo, R.; Coleman, A.; Coluccia, M.R.; Conceição, R.; Consolati, G.; Contreras, F.; Cooper, M.J.; Coutu, S.; Covault, C.E.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B.R.; Day, J.A.; de Almeida, R.M.; de Jong, S.J.; De Mauro, G.; de Mello Neto, J.R.T.; De Mitri, I.; de Oliveira, J.; de Souza, V.; Debatin, J.; Deligny, O.; Dhital, N.; Díaz Castro, M.L.; Diogo, F.; Dobrigkeit, C.; D'Olivo, J.C.; Dorosti, Q.; dos Anjos, R.C.; Dova, M.T.; Dundovic, A.; Ebr, J.; Engel, R.; Erdmann, M.; Escoba, C.O.; Etchegoyen, A.; Falcke, H.; Farmer, J.; Farrar, G.; Fauth, A.C.; Fazzi, N.; Feldbusch, F.; Fenu, F.; Ferreyro, L.P.; Figueira, J.M.; Filipčič, A.; Freire, M.M.; Fujii, T.; Fuster, A.; García, B.; Gemmeke, H.; Gherghel-Lascu, A.; Ghia, P.L.; Giaccari, U.; Giammarchi, M.; Giller, M.; Głas, D.; Glombitza, J.; Golup, G.; Gómez Berisso, M.; Gómez Vitale, P.F.; González, N.; Goos, I.; Góra, D.; Gorgi, A.; Gottowik, M.; Grubb, T.D.; Guarino, F.; Guedes, G.P.; Guido, E.; Halliday, R.; Hampel, M.R.; Hansen, P.; Harari, D.; Harrison, T.A.; Harvey, V.M.; Haungs, A.; Hebbeker, T.; Heck, D.; Heimann, P.; Hill, G.C.; Hojvat, C.; Holt, E.M.; Homola, P.; Hörandel, J.R.; Horvath, P.; Hrabovský, M.; Huege, T.; Hulsman, J.; Insolia, A.; Isar, P.G.; Jandt, I.; Johnsen, J.A.; Josebachuili, M.; Jurysek, J.; Kääpä, A.; Kampert, K.H.; Keilhauer, B.; Kemmerich, N.; Kemp, J.; Klages, H.O.; Kleifges, M.; Kleinfeller, J.; Krause, R.; Kuempel, D.; Kukec Mezek, G.; Kuotb Awad, A.; Lago, B.L.; LaHurd, D.; Lang, R.G.; Legumina, R.; Leigui de Oliveira, M.A.; Lenok, V.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Lo Presti, D.; Lopes, L.; López, R.; López Casado, A.; Lorek, R.; Luce, Q.; Lucero, A.; Malacari, M.; Mallamaci, M.; Mancarella, G.; Mandat, D.; Mantsc, P.; Mariazzi, A.G.; Mariş, I.C.; Marsella, G.; Martello, D.; Martinez, H.; Martínez Bravo, O.; Mathes, H.J.; Mathys, S.; Matthews, J.; Matthiae, G.; Mayotte, E.; Mazu, P.O.; Medina-Tanco, G.; Melo, D.; Menshikov, A.; Merenda, K.-D.; Michal, S.; Micheletti, M.I.; Middendorf, L.; Miramonti, L.; Mitrica, B.; Mockler, D.; Mollerach, S.; Montanet, F.; Morello, C.; Morlino, G.; Mostafá, M.; Müller, A.L.; Muller, M.A.; Müller, S.; Mussa, R.; Nellen, L.; Nguyen, P.H.; Niculescu-Oglinzanu, M.; Niechciol, M.; Nitz, D.; Nosek, D.; Novotny, V.; Nožka, L.; Nucita, A.; Núñez, L.A.; Olinto, A.; Palatka, M.; Pallotta, J.; Papenbreer, P.; Parente, G.; Parra, A.; Pech, M.; Pedreira, F.; Pękala, J.; Pelayo, R.; Peña-Rodriguez, J.; Pereira, L.A.S.; Perlin, M.; Perrone, L.; Peters, C.; Petrera, S.; Phuntsok, J.; Pierog, T.; Pimenta, M.; Pirronello, V.; Platino, M.; Poh, J.; Pont, B.; Porowski, C.; Prado, R.R.; Privitera, P.; Prouza, M.; Puyleart, A.; Querchfeld, S.; Quinn, S.; Ramos-Pollan, R.; Rautenberg, J.; Ravignani, D.; Reininghaus, M.; Ridky, J.; Riehn, F.; Risse, M.; Ristori, P.; Rizi, V.; Rodrigues de Carvalho, W.; Rodriguez Rojo, J.; Roncoroni, M.J.; Roth, M.; Roulet, E.; Rovero, A.C.; Ruehl, P.; Saffi, S.J.; Saftoiu, A.; Salamida, F.; Salazar, H.; Saleh, A.; Salina, G.; Sanabria Gomez, J.D.; Sánchez, F.; Santos, E.M.; Santos, E.; Sarazin, F.; Sarmento, R.; Sarmiento-Cano, C.; Sato, R.; Savina, P.; Schauer, M.; Scherini, V.; Schieler, H.; Schimassek, M.; Schimp, M.; Schmidt, D.; Scholten, O.; Schovánek, P.; Schröder, F.G.; Schröder, S.; Schumacher, J.; Sciutto, S.J.; Shellard, R.C.; Sigl, G.; Silli, G.; Sima, O.; Šmída, R.; Snow, G.R.; Sommers, P.; Soriano, J.F.; Souchard, J.; Squartini, R.; Stanca, D.; Stanič, S.; Stasielak, J.; Stassi, P.; Stolpovskiy, M.; Streich, A.; Suarez, F.; Suárez-Durán, M.; Sudholz, T.; Suomijärvi, T.; Supanitsky, A.D.; Šupík, J.; Szadkowski, Z.; Taboada, A.; Taborda, O.A.; Tapia, A.; Timmermans, C.; Todero Peixoto, C.J.; Tomé, B.; Torralba Elipe, G.; Travnicek, P.; Trini, M.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J.F.; Valiño, I.; Valore, L.; van Bodegom, P.; van den Berg, A.M.; van Vliet, A.; Varela, E.; Vargas Cárdenas, B.; Vázquez, R.A.; Veberič, D.; Ventura, C.; Vergara Quispe, I.D.; Verzi, V.; Vicha, J.; Villaseñor, L.; Vorobiov, S.; Wahlberg, H.; Wainberg, O.; Wat, A.A.; Weber, M.; Weindl, A.; Wiedeński, M.; Wiencke, L.; Wilczyński, H.; Winchen, T.; Wirtz, M.; Wittkowski, D.; Wundheiler, B.; Yang, L.; Yushkov, A.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zehrer, L.; Zepeda, A.; Zimmermann, B.; Ziolkowski, M.; Zong, Z.; Zuccarello, F.; Ebr, J.; Juryšek, J.; Prouza, M.; Blažek, Ji.; Trávníček, P.; Mandát, D.; Pech, M.; Karpov, S.; Cunniffe, R.; Mašek, M.; Jelínek, M.; Ebrová, I.Janeček, P.; Aab, A.; Abreu, P.; Aglietta, M.; Albuquerque, I. F. M.; Albury, J. M.; Allekotte, I.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Anastasi, G. A.; Anchordoqui, L.; Andrada, B.; Andringa, S.; Aramo, C.; Asorey, H.; Assis, P.; Avila, G.; Badescu, A. M.; Balaceanu, A.; Barbato, F.; Barreira Luz, R. J.; Baur, S.; Becker, K. H.; Bellido, J. A.; Berat, C.; Bertaina, M. E.; Bertou, X.; Bierman, P. L.; Biteau, J.; Blaess, S. G.; Blanco, A.; Blazek, J.; Bleve, C.; Boháčová, M.; Bonifazi, C.; Borodai, N.; Botti, A. M.; Brac, J.; Bretz, T.; Bridgeman, A.; Briechle, F. L.; Buchholz, P.; Bueno, A.; Buitink, S.; Buscemi, M.; Caballero-Mora, K. S.; Caccianiga, L.; Calcagni, L.; Cancio, A.; Canfora, F.; Carceller, J. M.; Caruso, R.; Castellina, A.; Catalani, F.; Cataldi, G.; Cazon, L.; Chinellato, J. A.; Chudoba, J.; Chytka, L.; Clay, R. W.; Cobos Cerutti, A. C.; Colalillo, R.; Coleman, A.; Coluccia, M. R.; Conceição, R.; Consolati, G.; Contreras, F.; Cooper, M. J.; Coutu, S.; Covault, C. E.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B. R.; Day, J. A.; de Almeida, R. M.; de Jong, S. J.; De Mauro, G.; de Mello Neto, J. R. T.; De Mitri, I.; de Oliveira, J.; de Souza, V.; Debatin, J.; Deligny, O.; Dhital, N.; Díaz Castro, M. L.; Diogo, F.; Dobrigkeit, C.; D'Olivo, J. C.; Dorosti, Q.; dos Anjos, R. C.; Dova, M. T.; Dundovic, A.; Ebr, J.; Engel, R.; Erdmann, M.; Escoba, C. O.; Etchegoyen, A.; Falcke, H.; Farmer, J.; Farrar, G.; Fauth, A. C.; Fazzi, N.; Feldbusch, F.; Fenu, F.; Ferreyro, L. P.; Figueira, J. M.; Filipčič, A.; Freire, M. M.; Fujii, T.; Fuster, A.; García, B.; Gemmeke, H.; Gherghel-Lascu, A.; Ghia, P. L.; Giaccari, U.; Giammarchi, M.; Giller, M.; Głas, D.; Glombitza, J.; Golup, G.; Gómez Berisso, M.; Gómez Vitale, P. F.; González, N.; Goos, I.; Góra, D.; Gorgi, A.; Gottowik, M.; Grubb, T. D.; Guarino, F.; Guedes, G. P.; Guido, E.; Halliday, R.; Hampel, M. R.; Hansen, P.; Harari, D.; Harrison, T. A.; Harvey, V. M.; Haungs, A.; Hebbeker, T.; Heck, D.; Heimann, P.; Hill, G. C.; Hojvat, C.; Holt, E. M.; Homola, P.; Hörandel, J. R.; Horvath, P.; Hrabovský, M.; Huege, T.; Hulsman, J.; Insolia, A.; Isar, P. G.; Jandt, I.; Johnsen, J. A.; Josebachuili, M.; Jurysek, J.; Kääpä, A.; Kampert, K. H.; Keilhauer, B.; Kemmerich, N.; Kemp, J.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Krause, R.; Kuempel, D.; Kukec Mezek, G.; Kuotb Awad, A.; Lago, B. L.; Lahurd, D.; Lang, R. G.; Legumina, R.; Leigui de Oliveira, M. A.; Lenok, V.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Lo Presti, D.; Lopes, L.; López, R.; López Casado, A.; Lorek, R.; Luce, Q.; Lucero, A.; Malacari, M.; Mallamaci, M.; Mancarella, G.; Mandat, D.; Mantsc, P.; Mariazzi, A. G.; Mariş, I. C.; Marsella, G.; Martello, D.; Martinez, H.; Martínez Bravo, O.; Mathes, H. J.; Mathys, S.; Matthews, J.; Matthiae, G.; Mayotte, E.; Mazu, P. O.; Medina-Tanco, G.; Melo, D.; Menshikov, A.; Merenda, K. -D.; Michal, S.; Micheletti, M. I.; Middendorf, L.; Miramonti, L.; Mitrica, B.; Mockler, D.; Mollerach, S.; Montanet, F.; Morello, C.; Morlino, G.; Mostafá, M.; Müller, A. L.; Muller, M. A.; Müller, S.; Mussa, R.; Nellen, L.; Nguyen, P. H.; Niculescu-Oglinzanu, M.; Niechciol, M.; Nitz, D.; Nosek, D.; Novotny, V.; Nožka, L.; Nucita, A.; Núñez, L. A.; Olinto, A.; Palatka, M.; Pallotta, J.; Papenbreer, P.; Parente, G.; Parra, A.; Pech, M.; Pedreira, F.; Pękala, J.; Pelayo, R.; Peña-Rodriguez, J.; Pereira, L. A. S.; Perlin, M.; Perrone, L.; Peters, C.; Petrera, S.; Phuntsok, J.; Pierog, T.; Pimenta, M.; Pirronello, V.; Platino, M.; Poh, J.; Pont, B.; Porowski, C.; Prado, R. R.; Privitera, P.; Prouza, M.; Puyleart, A.; Querchfeld, S.; Quinn, S.; Ramos-Pollan, R.; Rautenberg, J.; Ravignani, D.; Reininghaus, M.; Ridky, J.; Riehn, F.; Risse, M.; Ristori, P.; Rizi, V.; Rodrigues de Carvalho, W.; Rodriguez Rojo, J.; Roncoroni, M. J.; Roth, M.; Roulet, E.; Rovero, A. C.; Ruehl, P.; Saffi, S. J.; Saftoiu, A.; Salamida, F.; Salazar, H.; Saleh, A.; Salina, G.; Sanabria Gomez, J. D.; Sánchez, F.; Santos, E. M.; Santos, E.; Sarazin, F.; Sarmento, R.; Sarmiento-Cano, C.; Sato, R.; Savina, P.; Schauer, M.; Scherini, V.; Schieler, H.; Schimassek, M.; Schimp, M.; Schmidt, D.; Scholten, O.; Schovánek, P.; Schröder, F. G.; Schröder, S.; Schumacher, J.; Sciutto, S. J.; Shellard, R. C.; Sigl, G.; Silli, G.; Sima, O.; Šmída, R.; Snow, G. R.; Sommers, P.; Soriano, J. F.; Souchard, J.; Squartini, R.; Stanca, D.; Stanič, S.; Stasielak, J.; Stassi, P.; Stolpovskiy, M.; Streich, A.; Suarez, F.; Suárez-Durán, M.; Sudholz, T.; Suomijärvi, T.; Supanitsky, A. D.; Šupík, J.; Szadkowski, Z.; Taboada, A.; Taborda, O. A.; Tapia, A.; Timmermans, C.; Todero Peixoto, C. J.; Tomé, B.; Torralba Elipe, G.; Travnicek, P.; Trini, M.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van Bodegom, P.; van den Berg, A. M.; van Vliet, A.; Varela, E.; Vargas Cárdenas, B.; Vázquez, R. A.; Veberič, D.; Ventura, C.; Vergara Quispe, I. D.; Verzi, V.; Vicha, J.; Villaseñor, L.; Vorobiov, S.; Wahlberg, H.; Wainberg, O.; Wat, A. A.; Weber, M.; Weindl, A.; Wiedeński, M.; Wiencke, L.; Wilczyński, H.; Winchen, T.; Wirtz, M.; Wittkowski, D.; Wundheiler, B.; Yang, L.; Yushkov, A.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zehrer, L.; Zepeda, A.; Zimmermann, B.; Ziolkowski, M.; Zong, Z.; Zuccarello, F.; Ebr, J.; Juryšek, J.; Prouza, M.; Blažek, Ji.; Trávníček, P.; Mandát, D.; Pech, M.; Karpov, S.; Cunniffe, R.; Mašek, M.; Jelínek, M.; Ebrová, I

Sensitivity of the Cherenkov Telescope Array to a dark matter signal from the Galactic centre

Full list of authors: Acharyya, A.; Adam, R.; Adams, C.; Agudo, I.; Aguirre-Santaella, A.; Alfaro, R.; Alfaro, J.; Alispach, C.; Aloisio, R.; Alves Batista, R.; Amati, L.; Ambrosi, G.; Angüner, E. O.; Antonelli, L. A.; Aramo, C.; Araudo, A.; Armstrong, T.; Arqueros, F.; Asano, K.; Ascasíbar, Y. Ashley, M.; Balazs, C.; Ballester, O.; Baquero Larriva, A.; Barbosa Martins, V.; Barkov, M.; Barres de Almeida, U.; Barrio, J. A.; Bastieri, D.; Becerra, J.; Beck, G.; Becker Tjus, J.; Benbow, W.; Benito, M.; Berge, D.; Bernardini, E.; Bernlöhr, K.; Berti, A.; Bertucci, B.; Beshley, V.; Biasuzzi, B.; Biland, A.; Bissaldi, E.; Biteau, J.; Blanch, O.; Blazek, J.; Bocchino, F.; Boisson, C.; Bonneau Arbeletche, L.; Bordas, P.; Bosnjak, Z.; Bottacini, E.; Bozhilov, V.; Bregeon, J.; Brill, A.; Bringmann, T.; Brown, A. M.; Brun, P.; Brun, F.; Bruno, P.; Bulgarelli, A.; Burton, M.; Burtovoi, A.; Buscemi, M.; Cameron, R.; Capasso, M.; Caproni, A.; Capuzzo-Dolcetta, R.; Caraveo, P.; Carosi, R.; Carosi, A.; Casanova, S.; Cascone, E.; Cassol, F.; Catalani, F.; Cauz, D.; Cerruti, M.; Chadwick, P.; Chaty, S.; Chen, A.; Chernyakova, M.; Chiaro, G.; Chiavassa, A.; Chikawa, M.; Chudoba, J.; Çolak, M.; Conforti, V.; Coniglione, R.; Conte, F.; Contreras, J. L.; Coronado-Blazquez, J.; Costa, A.; Costantini, H.; Cotter, G.; Cristofari, P.; D'Aimath, A.; D'Ammando, F.; Damone, L. A.; Daniel, M. K.; Dazzi, F.; De Angelis, A.; De Caprio, V.; de Cássia dos Anjos, R.; de Gouveia Dal Pino, E. M.; De Lotto, B.; De Martino, D.; de Oña Wilhelmi, E.; De Palma, F.; de Souza, V.; Delgado, C.; Delgado Giler, A. G.; della Volpe, D.; Depaoli, D.; Di Girolamo, T.; Di Pierro, F.; Di Venere, L.; Diebold, S.; Dmytriiev, A.; Domínguez, A.; Donini, A.; Doro, M.; Ebr, J.; Eckner, C.; Edwards, T. D. P.; Ekoume, T. R. N.; Elsässer, D.; Evoli, C.; Falceta-Goncalves, D.; Fedorova, E.; Fegan, S.; Feng, Q.; Ferrand, G.; Ferrara, G.; Fiandrini, E.; Fiasson, A.; Filipovic, M.; Fioretti, V.; Fiori, M.; Foffano, L.; Fontaine, G.; Fornieri, O.; Franco, F. J.; Fukami, S.; Fukui, Y.; Gaggero, D.; Galaz, G.; Gammaldi, V.; Garcia, E.; Garczarczyk, M.; Gascon, D.; Gent, A.; Ghalumyan, A.; Gianotti, F.; Giarrusso, M.; Giavitto, G.; Giglietto, N.; Giordano, F.; Giuliani, A.; Glicenstein, J.; Gnatyk, R.; Goldoni, P.; González, M. M.; Gourgouliatos, K.; Granot, J.; Grasso, D.; Green, J.; Grillo, A.; Gueta, O.; Gunji, S.; Halim, A.; Hassan, T.; Heller, M.; Hernández Cadena, S.; Hiroshima, N.; Hnatyk, B.; Hofmann, W.; Holder, J.; Horan, D.; Hörandel, J.; Horvath, P.; Hovatta, T.; Hrabovsky, M.; Hrupec, D.; Hughes, G.; Humensky, T. B.; Hütten, M.; Iarlori, M.; Inada, T.; Inoue, S.; Iocco, F.; Iori, M.; Jamrozy, M.; Janecek, P.; Jin, W.; Jouvin, L.; Jurysek, J.; Karukes, E.; Katarzyński, K.; Kazanas, D.; Kerszberg, D.; Kherlakian, M. C.; Kissmann, R.; Knödlseder, J.; Kobayashi, Y.; Kohri, K.; Komin, N.; Kubo, H.; Kushida, J.; Lamanna, G.; Lapington, J.; Laporte, P.; Leigui de Oliveira, M. A.; Lenain, J.; Leone, F.; Leto, G.; Lindfors, E.; Lohse, T.; Lombardi, S.; Longo, F.; Lopez, A.; López, M.; López-Coto, R.; Loporchio, S.; Luque-Escamilla, P. L.; Mach, E.; Maggio, C.; Maier, G.; Mallamaci, M.; Malta Nunes de Almeida, R.; Mandat, D.; Manganaro, M.; Mangano, S.; Manicò, G.; Marculewicz, M.; Mariotti, M.; Markoff, S.; Marquez, P.; Martí, J.; Martinez, O.; Martínez, M.; Martínez, G.; Martínez-Huerta, H.; Maurin, G.; Mazin, D.; Mbarubucyeye, J. D.; Medina Miranda, D.; Meyer, M.; Miceli, M.; Miener, T.; Minev, M.; Miranda, J. 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C.; Siejkowski, H.; Silk, J.; Siqueira, C.; Sliusar, V.; Słowikowska, A.; Sokolenko, A.; Sol, H.; Spencer, S.; Stamerra, A.; Stanič, S.; Starling, R.; Stolarczyk, T.; Straumann, U.; Strišković, J.; Suda, Y.; Suomijarvi, T.; Świerk, P.; Tavecchio, F.; Taylor, L.; Tejedor, L. A.; Teshima, M.; Testa, V.; Tibaldo, L.; Todero Peixoto, C. J.; Tokanai, F.; Tonev, D.; Tosti, G.; Tosti, L.; Tothill, N.; Truzzi, S.; Travnicek, P.; Vagelli, V.; Vallage, B.; Vallania, P.; van Eldik, C.; Vandenbroucke, J.; Varner, G. S.; Vassiliev, V.; Vázquez Acosta, M.; Vecchi, M.; Ventura, S.; Vercellone, S.; Vergani, S.; Verna, G.; Viana, A.; Vigorito, C. F.; Vink, J.; Vitale, V.; Vorobiov, S.; Vovk, I.; Vuillaume, T.; Wagner, S. J.; Walter, R.; Watson, J.; Weniger, C.; White, R.; White, M.; Wiemann, R.; Wierzcholska, A.; Will, M.; Williams, D. A.; Wischnewski, R.; Yanagita, S.; Yang, L.; Yoshikoshi, T.; Zacharias, M.; Zaharijas, G.; Zakaria, A. A.; Zampieri, L.; Zanin, R.; Zaric, D.; Zavrtanik, M.; Zavrtanik, D.; Zdziarski, A. A.; Zech, A.; Zechlin, H.; Zhdanov, V. I.; Živec, M.-- This is an open access article published by IOP Publishing Ltd on behalf of Sissa Medialab. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.We provide an updated assessment of the power of the Cherenkov Telescope Array (CTA) to search for thermally produced dark matter at the TeV scale, via the associated gamma-ray signal from pair-annihilating dark matter particles in the region around the Galactic centre. We find that CTA will open a new window of discovery potential, significantly extending the range of robustly testable models given a standard cuspy profile of the dark matter density distribution. Importantly, even for a cored profile, the projected sensitivity of CTA will be sufficient to probe various well-motivated models of thermally produced dark matter at the TeV scale. This is due to CTA's unprecedented sensitivity, angular and energy resolutions, and the planned observational strategy. The survey of the inner Galaxy will cover a much larger region than corresponding previous observational campaigns with imaging atmospheric Cherenkov telescopes. CTA will map with unprecedented precision the large-scale diffuse emission in high-energy gamma rays, constituting a background for dark matter searches for which we adopt state-of-the-art models based on current data. Throughout our analysis, we use up-to-date event reconstruction Monte Carlo tools developed by the CTA consortium, and pay special attention to quantifying the level of instrumental systematic uncertainties, as well as background template systematic errors, required to probe thermally produced dark matter at these energies. © 2021 The Author(s).We gratefully acknowledge financial support from the following agencies and organisations: State Committee of Science of Armenia, Armenia; The Australian Research Council, Astronomy Australia Ltd, The University of Adelaide, Australian National University, Monash University, The University of New South Wales, The University of Sydney, Western Sydney University, Australia; Federal Ministry of Education, Science and Research, and Innsbruck University, Austria; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Fundacao de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ), Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP), Ministry of Science, Technology, Innovations and Communications (MCTIC), and Instituto Serrapilheira, Brasil; Ministry of Education and Science, National RI Roadmap Project DO1-153/28.08.2018, Bulgaria; The Natural Sciences and Engineering Research Council of Canada and the Canadian Space Agency, Canada; CONICYT-Chile grants CATA AFB 170002, ANID PIA/APOYO AFB 180002, ACT 1406, FONDECYT-Chile grants, 1161463, 1170171, 1190886, 1171421, 1170345, 1201582, Gemini-ANID 32180007, Chile; Croatian Science Foundation, Rudjer Boskovic Institute, University of Osijek, University of Rijeka, University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, University of Zagreb, Faculty of Electrical Engineering and Computing, Croatia; Ministry of Education, Youth and Sports, MEYS LM2015046, LM2018105, LTT17006, EU/MEYS CZ.02.1.01/0.0/0.0/16_013/0001403, CZ.02.1.01/0.0/0.0/18_046/0016007 and CZ.02.1.01/0.0/0.0/16_019/0000754, Czech Republic; Academy of Finland (grant nr.317636, 320045, 317383 and 320085), Finland; Ministry of Higher Education and Research, CNRS-INSU and CNRS-IN2P3, CEA-Irfu, ANR, Regional Council Ile de France, Labex ENIGMASS, OSUG2020, P2IO and OCEVU, France; Max Planck Society, BMBF, DESY, Helmholtz Association, Germany; Department of Atomic Energy, Department of Science and Technology, India; Istituto Nazionale di Astrofisica (INAF), Istituto Nazionale di Fisica Nucleare (INFN), MIUR, Istituto Nazionale di Astrofisica (INAF-OABRERA) Grant Fondazione Cariplo/Regione Lombardia ID 2014-1980/RST_ERC, Italy; ICRR, University of Tokyo, JSPS, MEXT, Japan; Netherlands Research School for Astronomy (NOVA), Netherlands Organization for Scientific Research (NWO), Netherlands; University of Oslo, Norway; Ministry of Science and Higher Education, DIR/WK/2017/12, the National Centre for Research and Development and the National Science Centre, UMO-2016/22/M/ST9/00583, Poland; Slovenian Research Agency, grants P1-0031, P1-0385, I0-0033, J1-9146, J1-1700, N1-0111, and the Young Researcher program, Slovenia; South African Department of Science and Technology and National Research Foundation through the South African Gamma-Ray Astronomy Programme, South Africa; The Spanish Ministry of Science and Innovation and the Spanish Research State Agency (AEI) through grants AYA2016-79724-C4-1-P, AYA2016-80889-P, AYA2016-76012-C3-1-P, BES-2016-076342, ESP2017-87055-C2-1-P, FPA2017-82729-C6-1-R, FPA2017-82729-C6-2-R, FPA2017-82729-C6-3-R, FPA2017-82729-C6-4-R, FPA2017-82729-C6-5-R, FPA2017-82729-C6-6-R, PGC2018-095161-B-I00, PGC2018-095512-B-I00; the \Centro de Excelencia Severo Ochoa"program through grants no. SEV-2015-0548, SEV-2016-0597, SEV-2016-0588, SEV-2017-0709; the "Unidad de Excelencia Maria de Maeztu" program through grant no. MDM-2015-0509; the "Ramon y Cajal" programme through grants RYC-2013-14511, RyC-2013-14660, RYC-2017-22665; and the MultiDark Consolider Network FPA2017-90566-REDC. Atraccion de Talento contract no. 2016-T1/TIC-1542 granted by the Comunidad de Madrid; the "Postdoctoral Junior Leader Fellowship" programme from La Caixa Banking Foundation, grants no. LCF/BQ/LI18/11630014 and LCF/BQ/PI18/11630012; the "Programa Operativo" FEDER2014-2020, Consejeria de Economia y Conocimiento de la Junta de Andalucia (ref. 1257737), PAIDI 2020 (ref. P18-FR-1580), and Universidad de Jaen; the Spanish AEI EQC2018-005094-P FEDER 2014-2020; the European Union's "Horizon 2020" research and innovation programme under Marie Sklodowska-Curie grant agreement no. 665919; and the ESCAPE project with grant no. GA:824064, Spain; Swedish Research Council, Royal Physiographic Society of Lund, Royal Swedish Academy of Sciences, The Swedish National Infrastructure for Computing (SNIC) at Lunarc (Lund), Sweden; State Secretariat for Education, Research and Innovation (SERI) and Swiss National Science Foundation (SNSF), Switzerland; Durham University, Leverhulme Trust, Liverpool University, University of Leicester, University of Oxford, Royal Society, Science and Technology Facilities Council, U.K.; U.S. National Science Foundation, U.S. Department of Energy, Argonne National Laboratory, Barnard College, University of California, University of Chicago, Columbia University, Georgia Institute of Technology, Institute for Nuclear and Particle Astrophysics (INPAC-MRPI program), Iowa State University, the Smithsonian Institution, Washington University McDonnell Center for the Space Sciences, The University of Wisconsin and the Wisconsin Alumni Research Foundation, U.S.A. The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreements No 262053 and No 317446. This project is receiving funding from the European Union's Horizon 2020 research and innovation programs under agreement No 676134.Peer reviewe

Analysis of simulation and reconstruction methods used by the Pierre Auger Observatory

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