Cosmogenic Backgrounds in Borexino at 3800 m water-equivalent depth

Journal Article · Thu Aug 01 00:00:00 EDT 2013 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2013/08/049· OSTI ID:22282741

Bellini, G.; Avanzini, M. Buizza; Caccianiga, B.; D'Angelo, D. ^[1]; Benziger, J. ^[2]; Bick, D. ^[3]; Bonfini, G.; Cavalcante, P.; Fomenko, K. ^[4]; Bravo, D. ^[5]; Cadonati, L. ^[6]; Calaprice, F.; Chavarria, A.; Galbiati, C. ^[7]; Chepurnov, A. ^[8]; Davini, S.; Empl, A. ^[9]; Derbin, A. ^[10]; Etenko, A. ^[11]; others, and

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1. Dipartimento di Fisica, Università degli Studi e INFN, Milano 20133 (Italy)
2. Chemical Engineering Department, Princeton University, Princeton, NJ 08544 (United States)
3. University of Hamburg, Hamburg (Germany)
4. INFN Laboratori Nazionali del Gran Sasso, Assergi 67010 (Italy)
5. Physics Department, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)
6. Physics Department, University of Massachusetts, Amherst 01003 (United States)
7. Physics Department, Princeton University, Princeton, NJ 08544 (United States)
8. Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics, Moscow 119234 (Russian Federation)
9. Department of Physics, University of Houston, Houston, TX 77204 (United States)
10. St. Petersburg Nuclear Physics Institute, Gatchina 188350 (Russian Federation)
11. NRC Kurchatov Institute, Moscow 123182 (Russian Federation)

The solar neutrino experiment Borexino, which is located in the Gran Sasso underground laboratories, is in a unique position to study muon-induced backgrounds in an organic liquid scintillator. In this study, a large sample of cosmic muons is identified and tracked by a muon veto detector external to the liquid scintillator, and by the specific light patterns observed when muons cross the scintillator volume. The yield of muon-induced neutrons is found to be Y{sub n} = (3.10±0.11)·10{sup −4} n/(μ·(g/cm{sup 2})). The distance profile between the parent muon track and the neutron capture point has the average value λ = (81.5±2.7) cm. Additionally the yields of a number of cosmogenic radioisotopes are measured for {sup 12}N, {sup 12}B, {sup 8}He, {sup 9}C, {sup 9}Li, {sup 8}B, {sup 6}He, {sup 8}Li, {sup 11}Be, {sup 10}C and {sup 11}C. All results are compared with Monte Carlo simulation predictions using the FLUKA and GEANT4 packages. General agreement between data and simulation is observed for the cosmogenic production yields with a few exceptions, the most prominent case being {sup 11}C yield for which both codes return about 50% lower values. The predicted μ-n distance profile and the neutron multiplicity distribution are found to be overall consistent with data.

• OSTI ID: 22282741
• Journal Information: Journal of Cosmology and Astroparticle Physics, Vol. 2013, Issue 08; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASTROPHYSICS
BERYLLIUM 11
BORON 8
CARBON 10
CARBON 11
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
G CODES
HELIUM 8
LIQUID SCINTILLATION DETECTORS
LITHIUM 9
MONTE CARLO METHOD
MULTIPLICITY
NEUTRINO DETECTION
NEUTRON REACTIONS
NEUTRONS
NITROGEN 12
SOLAR NEUTRINOS
UNDERGROUND