논문
Multi-messenger Observations of a Binary Neutron Star Merger
- 저자B.？P. Abbott et al. (J. J. Oh, S. H. Oh, E. J. Son, W. S. Kim)
- 학술지Astrophysical Journal letters 848
- 등재유형
- 게재일자(2017)
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn1.gif] {$\sim 1.7\,{\rm{s}}$} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg 2 at a luminosity distance of ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn2.gif] {${40}_{-8}^{+8}$} Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn3.gif] {$\,{M}_{\odot }$} . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn4.gif] {$\sim 40\,{\rm{Mpc}}$} ) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn5.gif] {$\sim 9$} and ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn6.gif] {$\sim 16$} days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r -process nuclei synthesized in the ejecta.
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn1.gif] {$\sim 1.7\,{\rm{s}}$} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg 2 at a luminosity distance of ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn2.gif] {${40}_{-8}^{+8}$} Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn3.gif] {$\,{M}_{\odot }$} . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn4.gif] {$\sim 40\,{\rm{Mpc}}$} ) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn5.gif] {$\sim 9$} and ##IMG## [http://ej.iop.org/images/2041-8205/848/2/L12/apjlaa91c9ieqn6.gif] {$\sim 16$} days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r -process nuclei synthesized in the ejecta.
