We analyzed the available LIGO data coincident with GRB 070201, a short duration hard spectrum γ-ray burst whose electromagnetically determined sky position is coincident with the spiral arms of the Andromeda galaxy (M31). Possible progenitors of such short hard GRBs include mergers of neutron stars or a neutron star and black hole, or soft γ-ray repeater (SGR) flares. These events can be accompanied by gravitational-wave emission. No plausible gravitational wave candidates were found within a 180 s long window around the time of GRB 070201. This result implies that a compact binary progenitor of GRB 070201, with masses in the range 1 M⊙ < m1 < 3 M⊙ and 1 M⊙ < m2 < 40 M⊙, located in M31 is excluded at > 99% confidence. Indeed, if GRB 070201 were caused by a binary neutron star merger, we find that D < 3.5 Mpc is excluded, assumingrandom inclination, at 90% confidence. The result also implies that an unmodeled gravitational wave burst from GRB 070201 most probably emitted less than 4.4×10-4M⊙c2 (7.9×1050 ergs) in any 100 ms long period within the signal region if the source was in M31 and radiated isotropically at the same frequency as LIGO's peak sensitivity ( f ≈ 150 Hz). This upper limit does not exclude current models of SGRs at the M31 distance.
- gamma ray
- neutron star
- gravitational wave bursts
- Andromeda galaxy
Abbott, B., Cantley, C. A., Lockerbie, N. A., Tokmakov, K. V., & LIGO Scientific Collaboration (2008). Implications for the origin of GRB 070201 from LIGO observations. Astrophysical Journal, 681(2), 1419-1430. https://doi.org/10.1086/587954