New measurement of the period for the 4th ULX pulsar - the supernova impostor SN2010da in NGC 300
ATel #11174; S. A. Grebenev, I. A. Mereminskiy (Space Research Institute, Moscow)
on 16 Jan 2018; 11:08 UT
Credential Certification: Sergei Grebenev (email@example.com)
Subjects: X-ray, Neutron Star, Pulsar
Following the discovery (Atel #11158) of the new (fourth) ULX pulsar (in the peculiar supergiant X-ray binary known as the supernova impostor SN 2010da located in NGC 300, at a distance of 1.86 Mpc) we note that SWIFT/XRT observed this galaxy again on April 16, 2017, and detected the source still in a bright X-ray state. The strong modulation of its flux was revealed with a barycentric period of 30.05+/-0.025 s. Its comparison with the period measured on December 20, 2016 (Atel #11158) gave the mean spin-up rate Pdot=(1.47+/-0.01) x 10-7 s s-1 which is fastest ever observed. The corresponding life-time of this pulsar (P/Pdot) is 6.7 years only.
We applied for new TOO observations of this source with SWIFT/XRT.