A limit on the Co-57 gamma-ray flux from SN 1987A

Journal Article · Thu Oct 01 04:00:00 EDT 1992 · Astrophysical Journal; (United States)

DOI:https://doi.org/10.1086/186550· OSTI ID:6818056

Gunji, S; Kamae, T; Miyazaki, S; Sekimoto, Y; Takahashi, T; Tamura, T; Tanaka, M; Yamaoka, N; Yamagami, T; Nomachi, M ^[1]

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1. Tokyo Univ. (Japan) Inst. of Space and Astronautical Science, Sagamihara (Japan) National Lab. for High Energy Physics, Tsukuba (Japan)

We studied the gamma-ray flux from SN 1987A with a balloon-borne detector in Brazil on November 29, 1990. By comparing on- and off-source data, we obtained limits to the total gamma-ray flux due to Co-57 decays and presumed pulsar activity. If the pulsar contribution is neglected, an upper limit is set to the total Co-57 contribution above 60 keV at 2.7 x 10 exp 4/sq cm/s where the 122 keV line contribution is 1.0 x 10 exp 4/sq cm/s. The corresponding limit on the abundance ratio of Co-57 and Co-56 is 3.4 times that of the sun. The present upper limit implies that the reported leveling off in the light curve of SN 1987A is primarily due to the pulsar activity. If the pulsar is Crab-like, the light curve requires an energy outflow greater than 0.95 x 10 exp 37 ergs/s (above 1 keV) now being supplied to SN 1987A by its presumed pulsar. 23 refs.

• OSTI ID: 6818056
• Journal Information: Astrophysical Journal; (United States), Journal Name: Astrophysical Journal; (United States) Vol. 397:2; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

663620* -- Physics of Radiations Other Than Neutrons-- (1992-)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ABUNDANCE
AIRSHIPS
BALLOONS
BETA DECAY RADIOISOTOPES
COBALT 57
COBALT ISOTOPES
COSMIC RADIO SOURCES
DAYS LIVING RADIOISOTOPES
DECAY
ELECTROMAGNETIC RADIATION
ELECTRON CAPTURE RADIOISOTOPES
ERUPTIVE VARIABLE STARS
GAMMA RADIATION
INTERMEDIATE MASS NUCLEI
IONIZING RADIATIONS
ISOTOPES
MONITORING
NUCLEAR REACTIONS
NUCLEI
ODD-EVEN NUCLEI
PULSARS
RADIATIONS
RADIOISOTOPES
STARS
SUPERNOVAE
VARIABLE STARS