Measurement of the atmospheric neutrino-induced upgoing muon flux using MACRO

M. Ambrosio(Istituto Nazionale di Fisica Nucleare, Sezione di Napoli), R. Antolini(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso), C. Aramo(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso), G. Auriemma(University of Basilicata), A. Baldini(University of Pisa), G. C. Barbarino(Istituto Nazionale di Fisica Nucleare, Sezione di Napoli), B. C. Barish(California Institute of Technology), G. Battistoni(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati), R. Bellotti(Istituto Nazionale di Fisica Nucleare, Sezione di Bari), C. Bemporad(University of Pisa), P. Bernardini(University of Salento), H. Bilokon(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati), V. Bisi(Istituto Nazionale di Fisica Nucleare, Sezione di Torino), C. Bloise(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati), Geoffrey C. Bower(Indiana University Bloomington), S. Bussino(Istituto Nazionale di Fisica Nucleare, Sezione di Roma I), F. Cafagna(Istituto Nazionale di Fisica Nucleare, Sezione di Bari), M. Calicchio(Istituto Nazionale di Fisica Nucleare, Sezione di Bari), D. Campana(Istituto Nazionale di Fisica Nucleare, Sezione di Napoli), M. Carboni(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati), M. Castellano(University of Bari Aldo Moro), S. Cecchini(National Academies of Sciences, Engineering, and Medicine), F. Cei(University of Pisa), V. Chiarella(Istituto Nazionale di Fisica Nucleare, Sezione di Torino), B. C. Choudhary(California Institute of Technology), S. Coutu, Leonarda De Benedictis(University of Bari Aldo Moro), G. de Cataldo(University of Bari Aldo Moro), H. Dekhissi(University of Bologna), C. De Marzo(University of Bari Aldo Moro), I. De Mitri(University of L'Aquila), J. E. Derkaoui(University of Bologna), M. De Vincenzi(Roma Tre University), A. Di Credico, O. Erriquez(University of Bari Aldo Moro), C. Favuzzi(University of Bari Aldo Moro), C. Forti(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati), P. Fusco(University of Bari Aldo Moro), G. Giacomelli(University of Bologna), T. Giannini(University of Pisa), N. Giglietto(University of Bari Aldo Moro), M. Giorgini(University of Bologna), M. Grassi(University of Pisa), L. Gray(California Institute of Technology), A. Grillo(Swarthmore College), F. Guarino(University of Naples Federico II), P. Guarnaccia(University of Bari Aldo Moro), C. Gustavino(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati), A. Habig(Boston University), K. Hanson(University of Michigan), A. Hawthorne(Indiana University Bloomington), R. Heinz(Indiana University Bloomington), Yuping Huang(California Institute of Technology), E. Iarocci(Sapienza University of Rome), E. Katsavounidis(California Institute of Technology), I. Katsavounidis(California Institute of Technology), E. Kearns(Boston University), H. Kim(California Institute of Technology), S. Kyriazopoulou(California Institute of Technology), E. Lamanna(Sapienza University of Rome), C. Lane(Drexel University), D. Levin(Sapienza University of Rome), P. Lipari(Sapienza University of Rome), N.P. Longley(Swarthmore College), M. J. Longo(University of Michigan), F. Maaroufi(University of Bologna), G. Mancarella(University of Salento), G. Mandrioli(University of Bologna), S. Manzoor(Pakistan Institute of Nuclear Science and Technology), A. Margiotta Neri(University of Bologna), A. Marini(Swarthmore College), D. Martello(University of Salento), A. Marzari‐Chiesa(University of Turin), M. N. Mazziotta(University of Bari Aldo Moro), C. Mazzotta(University of Salento), D. G. Michael(California Institute of Technology), S. Mikheyev(California Institute of Technology), L. S. Miller(Indiana University Bloomington), P. Monacelli(University of L'Aquila), T. Montaruli(University of Bari Aldo Moro), M. Monteno(University of Turin), S. Mufson(Indiana University Bloomington), J. Musser(Indiana University Bloomington), D. Nicolò(University of Pisa), R. Nolty(California Institute of Technology), C. Okada(Boston University), C. J. Orth(Boston University), G. Osteria(University of Naples Federico II), M. Ouchrif(University of Bologna), O. Palamara(University of Salento), V. Patera(Sapienza University of Rome), L. Patrizii(University of Bologna), R. Pazzi(University of Pisa), C.W. Peck(California Institute of Technology), S. Petrera(University of L'Aquila), P. Pistilli(Roma Tre University), V. Popa(University of Bologna), G. Pugliese(Sapienza University of Rome), A. Rainó(University of Bari Aldo Moro), J. Reynoldson(Swarthmore College), F. Ronga(Istituto Nazionale di Fisica Nucleare, Sezione di Bari), U. Rubizzo(University of Naples Federico II), A. Sanzgiri(University of Basilicata), C. Satriano(University of Basilicata), L. Satta(Sapienza University of Rome), E. Scapparone(Indiana University Bloomington), K. Scholberg(Boston University), A. Sciubba(Sapienza University of Rome), P. Serra-Lugaresi(University of Bologna), M. Severi(Sapienza University of Rome), M. Sioli(University of Bologna), M. Sitta(University of Turin), P. Spinelli(University of Bari Aldo Moro), M. Spinetti(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati), M. Spurio(University of Bologna), R. Steinberg(Drexel University), J. L. Stone(Boston University), Lawrence Sulak(Boston University), A. Surdo(University of Salento), G. Tarlé(University of Michigan), V. Togo(University of Bologna), D. Ugolotti(University of Bologna), M. Vakili(Texas A&M University), C. W. Walter(Boston University), R. Webb(Texas A&M University)
Physics Letters B
August 1, 1998
10.1016/s0370-2693(98)00885-5
Cited by 364Open Access
Full Text

Abstract

We present a measurement of the flux of neutrino-induced upgoing muons (<Eν>∼ 100 GeV) using the MACRO detector. The ratio of the number of observed to expected events integrated over all zenith angles is 0.74 ±0.036 (stat) ±0.046 (systematic) ±0.13 (theoretical). The observed zenith distribution for −1.0≤cosθ≤−0.1 does not fit well with the no oscillation expectation, giving a maximum probability for χ2 of 0.1%. The acceptance of the detector has been extensively studied using downgoing muons, independent analyses and Monte Carlo simulations. The other systematic uncertainties cannot be the source of the discrepancies between the data and expectations. We have investigated whether the observed number of events and the shape of the zenith distribution can be explained by a neutrino oscillation hypothesis. Fitting either the flux or zenith distribution independently yields mixing parameters of sin22θ=1.0 and Δm2 of a few times 10−3 eV2. However, the observed zenith distribution does not fit well with any expectations, giving a maximum probability for χ2 of 5% for the best oscillation hypothesis, and the combined probability for the shape and number of events is 17%. We conclude that these data favor a neutrino oscillation hypothesis, but with unexplained structure in the zenith distribution not easily explained by either the statistics or systematics of the experiment.

Related Papers

No related papers found

Powered by citation graph analysis