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Evidence for 1809 keV Gamma-Ray Emission from 26Al Decays in the Vela Region with INTEGRAL/SPI

Stephane Schanne·Patrick Sizun·David Maurin·Bertrand Cordier·Andreas von Kienlin·Clarisse Hamadache
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Abstract

The Vela region is a promising target for the detection of 1.8 MeV gamma-rays emitted by the decays of radioactive 26Al isotopes produced in hydrostatic or explosive stellar nucleosynthesis processes. COMPTEL has claimed 1.8 MeV gamma-ray detection from Vela at a 3sigma level with a flux of 3.6 10^-5 ph/cm^2/s. In this paper, we present first results of our search for 1.8 MeV gamma-rays from Vela with the spectrometer SPI aboard INTEGRAL. Using the data set acquired during 1.7 Ms at the end of 2005 in the frame of our AO-3 open-time observation, we determine a flux of (6.5 \pm 1.9(stat) \pm 2.4(syst)) 10^-5 ph/cm^2/s from 26Al decays in the Vela region.

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Stephane Schanne, Patrick Sizun, David Maurin, Bertrand Cordier, Andreas von Kienlin, Clarisse Hamadache. 2007-01-23. Evidence for 1809 keV Gamma-Ray Emission from 26Al Decays in the Vela Region with INTEGRAL/SPI. https://arxiv.org/abs/astro-ph/0701640

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