BATSE observations of classical novae
David M. Smith
Jerry Fishman, Alan Harmon
Jordi Gómez-Gomar, Jordi José, Jordi Isern
Detection of gamma-ray emission from classical novae, in the range between
30 and 511keV, would provide a crucial test of the thermonuclear runaway
(TNR) model. This emission results from the annihilation of positrons,
emitted by some radioactive nuclei (13N and 18F) synthesized during
the TNR; it has a short duration and is produced before the optical maximum.
Therefore, it can only be analyzed ä posteriori", once the nova has been
discovered optically. The capability to observe all the sky, together with
its high sensitivity in the low-energy range, make BATSE an ideal instrument
to detect this emission. Data analysis techniques previously applied for BATSE
observation of 511keV transients of short duration and occultation observations
that have been optimized for this study have been applied. The first results
from the systematic search in BATSE background data which is under way will be
presented, which include nearby novae that have exploded since CGRO launch.
Comparison with recent updated theoretical models is made in each case.
Results relative to the recent Nova Velorum 1999 will also be presented.
Although no positive detection has been obtained up to now, upper limits to
the emitted flux will be presented, together with comments on improvements
both on the theory and on the data analysis techniques that we envision from
File translated from TEX by TTH, version 2.32.
On 16 Jul 1999, 09:19.