| Autor: |
Giovanni Badino, P. V. Kortchaguin, V. G. Ryassny, G. Bologna, V. A. Kudryavtsev, F. F. Khalchukov, Elena Korolkova, O. Saavedra, P. Galeotti, W. Fulgione, Antonella Castellina, A. S. Malguin, V. L. Dadykin, V. F. Yakushev, L. Periale, O. G. Ryazhskaya, P. Antonioli, G. C. Trinchero, C. Castagnoli, V. B. Kortchaguin, G. T. Zatsepin, S. Vernetto, Marco Aglietta |
| Rok vydání: |
1992 |
| Předmět: |
|
| Zdroj: |
Astroparticle Physics. 1:1-9 |
| ISSN: |
0927-6505 |
| DOI: |
10.1016/0927-6505(92)90004-j |
| Popis: |
The LSD liquid scintillation detector has been operating since 1985 as an underground neutrino observatory in the Mont Blanc Laboratory with the main objective of detecting antineutrino bursts from collapsing stars. In August 1988 the construction of an additional lead and borex paraffin shield considerably reduced the radioactive background and increased the sensitivity of the apparatus. In this way the search for steady fluxes of low-energy neutrinos of different flavours through their interactions with free protons and carbon nuclei of the scintillator was made possible. No evidence for a galactic collapse was observed during the whole period of measurement. The corresponding 90% c.l. upper limit on the galactic collapses rate is 0.45 y −1 for a burst duration of ΔT ⩽ 10 s. After analysing the last 3 years data, the following 90% c.l. upper limits on the steady neutrino and antineutrino fluxes were obtained: Φ( \ gn e ) 4 \ gn e s −1 cm −2 9 ⩽ E ν ⩽ 50MeV Φ( \ gn e ) 3 \ gn e s −1 cm −2 20 ⩽ E ν ⩽ 50MeV Φ(ν e ) 3 ν e s −1 cm −2 25 ⩽ E ν ⩽ 50 MeV Φ(ν μ + τ ) 7 ν μ + τ s −1 cm −2 20 ⩽ E ν ⩽ 100 MeV Φ( \ gn μ + τ ) 7 \ gn μ + τ s −1 cm −2 20 ⩽ E ν ⩽ 100 MeV In particular comparing the obtained upper limit on the \ gn e flux for 9 ⩽ E ν ⩽ 20 MeV to the solar ν e flux predicted by the standard solar model in the same range of energy, we can exclude the possibility that more than 6.3% of the solar ν e 's flux can change to \ gn e . Finally the first limits on the flux of relic supernova neutrinos of all flavours as a function of the neutrino sea temperature are presented. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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