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The International School for Advanced Studies (SISSA) was founded in 1978 and was the first institution in Italy to promote post-graduate courses leading to a Doctor Philosophiae (or PhD) degree. A centre of excellence among Italian and international universities, the school has around 65 teachers, 100 post docs and 245 PhD students, and is located in Trieste, in a campus of more than 10 hectares with wonderful views over the Gulf of Trieste.
SISSA hosts a very high-ranking, large and multidisciplinary scientific research output. The scientific papers produced by its researchers are published in high impact factor, well-known international journals, and in many cases in the world's most prestigious scientific journals such as Nature and Science. Over 900 students have so far started their careers in the field of mathematics, physics and neuroscience research at SISSA.
A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory
The Pierre Auger collaboration, P. Abreu64, M. Aglietta52, M. Ahlers94, E.J. Ahn82, I.F.M. Albuquerque16, D. Allard29, I. Allekotte1, J. Allen86, P. Allison88, A. Almela7,11, J. Alvarez Castillo57, J. Alvarez-Muñiz74, M. Ambrosio46, A. Aminaei58, L. Anchordoqui95, S. Andringa64, T. Antici'c24, C. Aramo46, E. Arganda4,71, F. Arqueros71, H. Asorey1, P. Assis64, J. Aublin31, M. Ave37, M. Avenier32, G. Avila10, T. Bäcker41, A.M. Badescu67, M. Balzer36, K.B. Barber12, A.F. Barbosa13, R. Bardenet30, S.L.C. Barroso19, B. Baughman88,99, J. Bäuml35, J.J. Beatty88, B.R. Becker93, K.H. Becker34, A. Bellétoile33, J.A. Bellido12, S. BenZvi94, C. Berat32, X. Bertou1, P.L. Biermann38, P. Billoir31, F. Blanco71, M. Blanco72, C. Bleve34, H. Blümer35,37, M. Bohácová26, D. Boncioli47, C. Bonifazi22,31, R. Bonino52, N. Borodai62, J. Brack80, I. Brancus65, P. Brogueira64, W.C. Brown81, R. Bruijn76,101, P. Buchholz41, A. Bueno73, R.E. Burton78, K.S. Caballero-Mora89, B. Caccianiga44, L. Caramete38, R. Caruso48, A. Castellina52, O. Catalano51, G. Cataldi45, L. Cazon64, R. Cester49, J. Chauvin32, S.H. Cheng89, A. Chiavassa52, J.A. Chinellato17, J. Chirinos Diaz85, J. Chudoba26, M. Cilmo46, R.W. Clay12, M.R. Coluccia45, R. Conceição64, F. Contreras9, H. Cook76, M.J. Cooper12, J. Coppens58,60, A. Cordier30, S. Coutu89, C.E. Covault78, A. Creusot29, A. Criss89, J. Cronin91, A. Curutiu38, S. Dagoret-Campagne30, R. Dallier33, S. Dasso3,5, K. Daumiller35, B.R. Dawson12, R.M. de Almeida23, M. De Domenico48, C. De Donato57, S.J. de Jong58,60, G. De La Vega8, W.J.M. de Mello Junior17, J.R.T. de Mello Neto22, I. De Mitri45, V. de Souza15, K.D. de Vries59, L. del Peral72, M. del Río9,47, O. Deligny28, H. Dembinski37, N. Dhital85, C. Di Giulio43, M.L. Díaz Castro14, P.N. Diep96, F. Diogo64, C. Dobrigkeit17, W. Docters59, J.C. D'Olivo57, P.N. Dong28,96, A. Dorofeev80, J.C. dos Anjos13, M.T. Dova4, D. D'Urso46, I. Dutan38, J. Ebr26, R. Engel35, M. Erdmann39, C.O. Escobar17,82, J. Espadanal64, A. Etchegoyen7,11, P. Facal San Luis91, I. Fajardo Tapia57, H. Falcke58,61, G. Farrar86, A.C. Fauth17, N. Fazzini82, A.P. Ferguson78, B. Fick85, A. Filevich7, A. Filipcic68,69, S. Fliescher39, C.E. Fracchiolla80, E.D. Fraenkel59, O. Fratu67, U. Fröhlich41, B. Fuchs13, R. Gaior31, R.F. Gamarra7, S. Gambetta42, B. García8, S.T. Garcia Roca74, D. Garcia-Gamez30, D. Garcia-Pinto71, A. Gascon73, H. Gemmeke36, P.L. Ghia31, U. Giaccari45, M. Giller63, H. Glass82, M.S. Gold93, G. Golup1, F. Gomez Albarracin4, M. Gómez Berisso1, P.F. Gómez Vitale10, P. Gonçalves64, D. Gonzalez37, J.G. Gonzalez35, B. Gookin80, A. Gorgi52, P. Gouffon16, E. Grashorn88, S. Grebe58,60, N. Griffith88, M. Grigat39, A.F. Grillo53, Y. Guardincerri3, F. Guarino46, G.P. Guedes18, A. Guzman57, J.D. Hague93, P. Hansen4, D. Harari1, S. Harmsma59,60, T.A. Harrison12, J.L. Harton80, A. Haungs35, T. Hebbeker39, D. Heck35, A.E. Herve12, C. Hojvat82, N. Hollon91, V.C. Holmes12, P. Homola62, J.R. Hörandel58, A. Horneffer58, P. Horvath27, M. Hrabovský26,27, T. Huege35, A. Insolia48, F. Ionita91, A. Italiano48, C. Jarne4, S. Jiraskova58, M. Josebachuili7, K. Kadija24, K.H. Kampert34, P. Karhan25, P. Kasper82, B. Kégl30, B. Keilhauer35, A. Keivani84, J.L. Kelley58, E. Kemp17, R.M. Kieckhafer85, H.O. Klages35, M. Kleifges36, J. Kleinfeller9,35, J. Knapp76, D.-H. Koang32, K. Kotera91, N. Krohm34, O. Krömer36, D. Kruppke-Hansen34, F. Kuehn82, D. Kuempel34,41, J.K. Kulbartz40, N. Kunka36, G. La Rosa51, C. Lachaud29, R. Lauer93, P. Lautridou33, S. Le Coz32, M.S.A.B. Leão21, D. Lebrun32, P. Lebrun82, M.A. Leigui de Oliveira21, A. Letessier-Selvon31, I. Lhenry-Yvon28, K. Link37, R. López54, A. Lopez Agüera74, K. Louedec30,32, J. Lozano Bahilo73, L. Lu76, A. Lucero7, M. Ludwig37, H. Lyberis28, C. Macolino31, S. Maldera52, D. Mandat26, P. Mantsch82, A.G. Mariazzi4, J. Marin9,52, V. Marin33, I.C. Maris31, H.R. Marquez Falcon56, G. Marsella50, D. Martello45, L. Martin33, H. Martinez55, O. Martínez Bravo54, H.J. Mathes35, J. Matthews84,90, J.A.J. Matthews93, G. Matthiae47, D. Maurel35, D. Maurizio49, P.O. Mazur82, G. Medina-Tanco57, M. Melissas37, D. Melo7, E. Menichetti49, A. Menshikov36, P. Mertsch75, C. Meurer39, S. Mi'canovi'c24, M.I. Micheletti6, I.A. Minaya71, L. Miramonti44, L. Molina-Bueno73, S. Mollerach1, M. Monasor91, D. Monnier Ragaigne30, F. Montanet32, B. Morales57, C. Morello52, E. Moreno54, J.C. Moreno4, M. Mostafá80, C.A. Moura21, M.A. Muller17, G. Müller39, M. Münchmeyer31, R. Mussa49, G. Navarra52,97, J.L. Navarro73, S. Navas73, P. Necesal26, L. Nellen57, A. Nelles58,60, J. Neuser34, P.T. Nhung96, M. Niechciol41, L. Niemietz34, N. Nierstenhoefer34, D. Nitz85, D. Nosek25, L. Nožka26, M. Nyklicek26, J. Oehlschläger35, A. Olinto91, M. Ortiz71, N. Pacheco72, D. Pakk Selmi-Dei17, M. Palatka26, J. Pallotta2, N. Palmieri37, G. Parente74, E. Parizot29, A. Parra74, S. Pastor70, T. Paul87, M. Pech26, J. Pekala62, R. Pelayo54,74, I.M. Pepe20, L. Perrone50, R. Pesce42, E. Petermann92, S. Petrera43, P. Petrinca47, A. Petrolini42, Y. Petrov80, J. Petrovic60, C. Pfendner94, R. Piegaia3, T. Pierog35, P. Pieroni3, M. Pimenta64, V. Pirronello48, M. Platino7, V.H. Ponce1, M. Pontz41, A. Porcelli35, P. Privitera91, M. Prouza26, E.J. Quel2, S. Querchfeld34, J. Rautenberg34, O. Ravel33, D. Ravignani7, B. Revenu33, J. Ridky26, S. Riggi74, M. Risse41, P. Ristori2, H. Rivera44, V. Rizi43, J. Roberts86, W. Rodrigues de Carvalho74, G. Rodriguez74, J. Rodriguez Martino9, J. Rodriguez Rojo9, I. Rodriguez-Cabo74, M.D. Rodríguez-Frías72, G. Ros72, J. Rosado71, T. Rossler27, M. Roth35, B. Rouillé-d'Orfeuil91, E. Roulet1, A.C. Rovero5, C. Rühle36, A. Saftoiu65, F. Salamida28, H. Salazar54, F. Salesa Greus80, G. Salina47, F. Sánchez7, C.E. Santo64, E. Santos64, E.M. Santos22, F. Sarazin79, B. Sarkar34, S. Sarkar75, R. Sato9, N. Scharf39, V. Scherini44, H. Schieler35, P. Schiffer39,40, A. Schmidt36, O. Scholten59, H. Schoorlemmer58,60, J. Schovancova26, P. Schovánek26, F. Schröder35, S. Schulte39, D. Schuster79, S.J. Sciutto4, M. Scuderi48, A. Segreto51, M. Settimo41, A. Shadkam84, R.C. Shellard13,14, I. Sidelnik7, G. Sigl40, H.H. Silva Lopez57, O. Sima66, A. 'Smiałkowski63, R. Šmída35, G.R. Snow92, P. Sommers89, J. Sorokin12, H. Spinka77,82, R. Squartini9, Y.N. Srivastava87, S. Stanic69, J. Stapleton88, J. Stasielak62, M. Stephan39, A. Stutz32, F. Suarez7, T. Suomijärvi28, A.D. Supanitsky5, T. Šuša24, M.S. Sutherland84, J. Swain87, Z. Szadkowski63, M. Szuba35, A. Tapia7, M. Tartare32, O. Taşcău34, C.G. Tavera Ruiz57, R. Tcaciuc41, D. Tegolo48, N.T. Thao96, D. Thomas80, J. Tiffenberg3, C. Timmermans58,60, W. Tkaczyk63, C.J. Todero Peixoto15, G. Toma65, B. Tomé64, A. Tonachini49, P. Travnicek26, D.B. Tridapalli16, G. Tristram29, E. Trovato48, M. Tueros74, R. Ulrich35, M. Unger35, M. Urban30, J.F. Valdés Galicia57, I. Valiño74, L. Valore46, A.M. van den Berg59, E. Varela54, B. Vargas Cárdenas57, J.R. Vázquez71, R.A. Vázquez74, D. Veberic68,69, V. Verzi47, J. Vicha26, M. Videla8, L. Villaseñor56, H. Wahlberg4, P. Wahrlich12, O. Wainberg7,11, D. Walz39, A.A. Watson76, M. Weber36, K. Weidenhaupt39, A. Weindl35, F. Werner37, S. Westerhoff94, B.J. Whelan12, A. Widom87, G. Wieczorek63, L. Wiencke79, B. Wilczyńska62, H. Wilczyński62, M. Will35, C. Williams91, T. Winchen39, M. Wommer35, B. Wundheiler7, T. Yamamoto91,98, T. Yapici85, P. Younk41,83, G. Yuan84, A. Yushkov74, B. Zamorano73, E. Zas74, D. Zavrtanik68,69, M. Zavrtanik68,69, I. Zaw86,100, A. Zepeda55, Y. Zhu36, M. Zimbres Silva17,34 and M. Ziolkowski41
Observations of cosmic ray arrival directions made with the
Pierre Auger Observatory have previously provided evidence of
anisotropy at the 99% CL using the correlation of ultra high
energy cosmic rays (UHECRs) with objects drawn from the
Véron-Cetty Véron catalog. In this paper we report on
the use of three catalog independent methods to search for
anisotropy. The 2pt–L, 2pt+ and 3pt methods, each giving a
different measure of self-clustering in arrival directions, were
tested on mock cosmic ray data sets to study the impacts of sample
size and magnetic smearing on their results, accounting for both
angular and energy resolutions. If the sources of UHECRs follow the
same large scale structure as ordinary galaxies in the local
Universe and if UHECRs are deflected no more than a few degrees, a
study of mock maps suggests that these three methods can efficiently
respond to the resulting anisotropy with a P-value = 1.0% or
smaller with data sets as few as 100 events. Using data taken from
January 1, 2004 to July 31, 2010 we examined the 20,30,...,110
highest energy events with a corresponding minimum energy threshold
of about 49.3 EeV. The minimum P-values found were 13.5% using
the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using
the 3pt method for the highest 100 energy events. In view of the
multiple (correlated) scans performed on the data set, these
catalog-independent methods do not yield strong evidence of
anisotropy in the highest energy cosmic rays.