As part of a series of experiments to search for antimatter in cosmic rays, the New Mexico State University balloon-borne magnet spectrometer was configured for a flight to study positrons. Two completely new instruments, a transition radiation detector and a silicon-tungsten imaging calorimeter, were added to the magnet spectrometer. These two detectors provided a proton rejection factor better than 3 x 10(4). This instrument was flown from Fort Sumner, New Mexico, at an average depth of 4.5 g cm(-2) of residual atmosphere for a period of 25 hr. We report here the measured fraction of positrons e(+)/(e(+) + e(-)) from similar to 5 to 60 GeV at the top of the atmosphere. Our measurements do not show any compelling evidence for an increase in this ratio with energy, and our results are consistent with a constant fraction of 0.078 +/- 0.016 over the entire energy region

Measurement of the Positron to Electron Ratio in the Cosmic Rays above 5 GeV / Golden, Rl; Stochaj, Sj; Stephens, Sa; Aversa, F; Barbiellini, G; Boezio, M; Bravar, U; Colavita, A; Fratnik, F; Schiavon, P; Vacchi, A; Zampa, N; Mitchell, Jw; Ormes, Jf; Streitmatter, Re; Bellotti, R; Cafagna, F; Castellano, Marcello; Circella, M; Decataldo, G; Demarzo, C; Giglietto, Nicola; Marangelli, B; Raino, A; Spinelli, P; Bocciolini, M; Finetti, N; Papini, P; Perego, A; Piccardi, S; Spillantini, P; Basini, G; Brancaccio, Fm; Ricci, M; Brunetti, Mt; Codino, A; Grimani, C; Menichelli, M; Bidoli, V; Candusso, M; Casolino, M; Depascale, Mp; Morselli, A; Picozza, P; Sparvoli, R; Hof, M; Menn, W; Simon, M.. - In: THE ASTROPHYSICAL JOURNAL. - ISSN 0004-637X. - STAMPA. - 457:2(1996), pp. 103-106. [10.1086/309896]

Measurement of the Positron to Electron Ratio in the Cosmic Rays above 5 GeV

Castellano, Marcello;GIGLIETTO, Nicola;
1996-01-01

Abstract

As part of a series of experiments to search for antimatter in cosmic rays, the New Mexico State University balloon-borne magnet spectrometer was configured for a flight to study positrons. Two completely new instruments, a transition radiation detector and a silicon-tungsten imaging calorimeter, were added to the magnet spectrometer. These two detectors provided a proton rejection factor better than 3 x 10(4). This instrument was flown from Fort Sumner, New Mexico, at an average depth of 4.5 g cm(-2) of residual atmosphere for a period of 25 hr. We report here the measured fraction of positrons e(+)/(e(+) + e(-)) from similar to 5 to 60 GeV at the top of the atmosphere. Our measurements do not show any compelling evidence for an increase in this ratio with energy, and our results are consistent with a constant fraction of 0.078 +/- 0.016 over the entire energy region
1996
Measurement of the Positron to Electron Ratio in the Cosmic Rays above 5 GeV / Golden, Rl; Stochaj, Sj; Stephens, Sa; Aversa, F; Barbiellini, G; Boezio, M; Bravar, U; Colavita, A; Fratnik, F; Schiavon, P; Vacchi, A; Zampa, N; Mitchell, Jw; Ormes, Jf; Streitmatter, Re; Bellotti, R; Cafagna, F; Castellano, Marcello; Circella, M; Decataldo, G; Demarzo, C; Giglietto, Nicola; Marangelli, B; Raino, A; Spinelli, P; Bocciolini, M; Finetti, N; Papini, P; Perego, A; Piccardi, S; Spillantini, P; Basini, G; Brancaccio, Fm; Ricci, M; Brunetti, Mt; Codino, A; Grimani, C; Menichelli, M; Bidoli, V; Candusso, M; Casolino, M; Depascale, Mp; Morselli, A; Picozza, P; Sparvoli, R; Hof, M; Menn, W; Simon, M.. - In: THE ASTROPHYSICAL JOURNAL. - ISSN 0004-637X. - STAMPA. - 457:2(1996), pp. 103-106. [10.1086/309896]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11589/1082
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