We report on the positron to electron ratio in the cosmic radiation over more than one decade in energy from 0.85 to 14 GeV, using the NMSU-WiZard/CAPRICE balloon borne magnet spectrometer. The spectrometer uses a solid radiator RICH detector and a silicon-tungsten calorimeter for particle identification. The proton rejection factor of the two instruments combined is better than 2 × 10-6 between 0.6 and 3 GV/c dropping to 6 × 10-5 at 5 GV/c and 10-4 at 10 GV/c. The data was collected during 23 hours at a mean residual atmosphere of 4.0 g/cm2. Prom a total of 2756 well identified e- and 498 e+ we are able to construct the positron fraction R = e+ /(e+ + e-) as a function of energy with small errors from 0.85 GeV to 14 GeV for the first time. We observe a decreasing ratio in this energy region. This energy dependent behaviour is consistent with the simple leaky box model. The positron fraction in the upper energy bins are in agreement with the latest high energy measurements.

Barbiellini, G., Basini, G., Bellotti, R., Bocciolini, M., Boezio, M., Massimo Brancaccio, F., et al. (1996). The cosmic-ray positron-to-electron ratio in the energy range 0.85 to 14 GeV. ASTRONOMY & ASTROPHYSICS, 309(1).

The cosmic-ray positron-to-electron ratio in the energy range 0.85 to 14 GeV

PICOZZA, PIERGIORGIO;SPARVOLI, ROBERTA;
1996-01-01

Abstract

We report on the positron to electron ratio in the cosmic radiation over more than one decade in energy from 0.85 to 14 GeV, using the NMSU-WiZard/CAPRICE balloon borne magnet spectrometer. The spectrometer uses a solid radiator RICH detector and a silicon-tungsten calorimeter for particle identification. The proton rejection factor of the two instruments combined is better than 2 × 10-6 between 0.6 and 3 GV/c dropping to 6 × 10-5 at 5 GV/c and 10-4 at 10 GV/c. The data was collected during 23 hours at a mean residual atmosphere of 4.0 g/cm2. Prom a total of 2756 well identified e- and 498 e+ we are able to construct the positron fraction R = e+ /(e+ + e-) as a function of energy with small errors from 0.85 GeV to 14 GeV for the first time. We observe a decreasing ratio in this energy region. This energy dependent behaviour is consistent with the simple leaky box model. The positron fraction in the upper energy bins are in agreement with the latest high energy measurements.
1996
Pubblicato
Rilevanza internazionale
Articolo
Sì, ma tipo non specificato
Settore FIS/04 - FISICA NUCLEARE E SUBNUCLEARE
English
Cosmic rays: abundances; Elementary particles
Barbiellini, G., Basini, G., Bellotti, R., Bocciolini, M., Boezio, M., Massimo Brancaccio, F., et al. (1996). The cosmic-ray positron-to-electron ratio in the energy range 0.85 to 14 GeV. ASTRONOMY & ASTROPHYSICS, 309(1).
Barbiellini, G; Basini, G; Bellotti, R; Bocciolini, M; Boezio, M; Massimo Brancaccio, F; Bravar, U; Cafagna, F; Candusso, M; Carlson, P; Casolino, M; Castellano, M; Circella, M; Codino, A; De Cataldo, G; De Marzo, C; De Pascale, Mp; Finetti, N; Francke, T; Giglietto, N; Golden, Rl; Grimani, C; Hof, M; Marangelli, B; Menn, W; Mitchell, Jw; Morselli, A; Ormes, Jf; Papini, P; Perego, A; Piccardi, S; Picozza, P; Ricci, M; Schiavon, P; Simon, M; Sparvoli, R; Spillatini, P; Spinelli, P; Stephens, Sa; Stochaj, Sj; Streitmatter, Re; Suffert, M; Vacchi, A; Weber, N; Zampa, N
Articolo su rivista
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/55511
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact