Search for redshifted 2.2 MeV neutron capture line from A0535+262 in outburst
Çalışkan, Şirin and Kalemci, Emrah and Baring, Matthew G. and Boggs, Steven E. and Kretschmar, Peter (2008) Search for redshifted 2.2 MeV neutron capture line from A0535+262 in outburst. (Accepted/In Press) AbstractJune 2005, followed by a dimmer outburst in August-September 2005. This
increased intensity provided an opportunity to search for redshifted neutroncapture
lines from the surface of the neutron star. If discovered, such lines would
constrain the neutron star equation of state, providing the motivation of this
search. The spectrometer (SPI) on board the INTEGRAL satellite observed the
dimmer outburst and provided the data for this research. We have not detected
a line with enough significance, with the width-dependent upper limits on the
broadened and redshifted neutron capture line in the range of (2 – 11) × 10−4
photons cm−2 s−1. To our knowledge, these are the strongest upper limits on
the redshifted 2.2 MeV emission from an accreting neutron star. Our analysis
of the transparency of the neutron star surface for 2.2 MeV photons shows that
photons have a small but finite chance of leaving the atmosphere unscattered,
which diminishes the possibility of detection. Available Versions of this ItemRepository Staff Only: item control page
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