GRB 110328A

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GRB 110328A
GRB 110328A (captured by the Hubble Space Telescope).jpg
Swift J1644+57 imaged by Hubble Space Telescope.
Other designations GRB 110328A , Swift J164449.3+573451 , Sw 1644+57
Event type gamma-ray burst
Date 28 March 2011
Duration months, perhaps a year[1]
Instrument Swift Gamma-Ray Burst Mission
Constellation Draco
Right ascension 16h 44m 49.97s
Declination +57° 34′ 59.7″[2]
Distance 3.8 billion light-years (920 Mpc)
Redshift 0.35±0.01
Total energy output 5×1048 ergs (assuming beamed emission)
See also

Swift J1644+57 (also indicated as GRB 110328A when it was discovered) is the name of the event that was observed on March 28, 2011, the tidal disruption of a star by a supermassive black hole. It has been detected by the Swift Gamma-Ray Burst Mission on March 28, 2011.[3] It occurred in the center of a small galaxy in the Draco constellation, about 3.8 billion light-years away.[4]

Studied by dozens of telescopes, it is one of the most puzzling cosmic blasts of high-energy radiation ever observed when it comes to brightness, variability and durability.[5] It probably occurred when a star wandered too close to the central black hole in the galaxy, and was gravitationally torn apart and swallowed by it.[3][6][7][8] Timing considerations suggest that the tidally disrupted star was a white dwarf and not a regular main sequence star.[9]

Debris now encircles the black hole in an accretion disk, which launches bipolar jets at near the speed of light. Jet plasma emits the γ- and X-rays. The beam of radiation from one of these jets points directly toward Earth, enhancing the apparent brightness. Repetitive dimming and softening of the X-rays implies that the jet temporarily tilts away from us, due to precession of the warped disk.[10]

The jets drive shocks into the surrounding interstellar medium, resulting in a radio to infrared afterglow. Detection of the relativistically expanding afterglow confirmed the identity of the host galaxy.[11] Observed linear polarization of the infrared radiation is consistent with synchrotron emission from the afterglow shock.[12]

"This is truly different from any explosive event we have seen before," said Joshua Bloom of the University of California at Berkeley, the lead author of the study published in the June 2011 issue of Science.[8][13]

See also[edit]


  1. ^ "Gamma-ray flash came from star being eaten by massive black hole". e! Science News. 2011-06-16. Retrieved 2011-06-17. 
  2. ^ "NASA Telescopes Join Forces to Observe Unprecedented Explosion". HubbleSite. Retrieved 2011-04-21. 
  3. ^ a b Joshua S. Bloom; et al. (2011-03-30). "GRB 110328A / Swift J164449.3+573451: X-ray analysis and a mini-blazar analogy". GCN Circulars 11847 (30 March 2011). 
  4. ^ "GRB 110328A: Chandra Observes Extraordinary Event". Harvard-Smithsonian Center for Astrophysics. Retrieved 2011-04-21. 
  5. ^ "NASA Telescopes Join Forces to Observe Unprecedented Explosion". NASA. 2011-04-07. Retrieved 2011-04-22. 
  6. ^ Barres de Almeida; De Angelis (2011-04-13). "Enhanced emission from GRB 110328A could be evidence for tidal disruption of a star". arXiv:1104.2528free to read. 
  7. ^ Coco, Alejandro (2011-04-10). "The Most Intense Cosmic Explosion Ever Seen". Scienceray. Retrieved 2011-04-22. 
  8. ^ a b University of California, Berkeley. "Unusual gamma-ray flash may have come from star being eaten by massive black hole". PhysOrg. Retrieved 16 June 2011. 
  9. ^ Krolik J.; Piran T. (2011-04-13). "Swift J1644+57: A White Dwarf Tidally Disrupted by a 10^4 M_{odot} Black Hole?". arXiv:1106.0923free to read. 
  10. ^ Saxton, C. J.; Soria, R.; Wu, K.; Kuin, N. P. M. (2012-01-25). "Long-term X-ray variability of Swift J1644+57". arXiv:1201.5210free to read.  External link in |title= (help)
  11. ^ Zauderer, B. A.; Berger, E.; Soderberg, A. M.; Loeb, A.; Narayan, R.; Frail, D. A.; Petitpas, G. R.; Brunthaler, A.; Chornock, R.; Carpenter, J. M.; Pooley, G. G.; Mooley, K.; Kulkarni, S. R.; Margutti, R.; Fox, D. B.; Nakar, E.; Patel, N. A.; Volgenau, N. H.; Culverhouse, T. L.; Bietenholz, M. F.; Rupen, M. P.; Max-Moerbeck, W.; Readhead, A. C. S.; Richards, J.; Shepherd, M.; Storm, S.; Hull, C. L. H., B. A. (2011). "Birth of a relativistic outflow in the unusual γ-ray transient Swift J164449.3+573451". Nature. 476 (7361): 425–428. arXiv:1106.3568free to read. Bibcode:2011Natur.476..425Z. doi:10.1038/nature10366. 
  12. ^ Wiersema, K.; van der Horst, A. J.; Levan, A. J.; Tanvir, N. R.; Karjalainen, R.; Kamble, A.; Kouveliotou, C.; Metzger, B. D.; Russell, D. M.; Skillen, I.; Starling, R. L. C.; Wijers, R. A. M. J. (2011-12-13). "Polarimetry of the transient relativistic jet of GRB 110328 / Swift J164449.3+573451". arXiv:1112.3042free to read.  External link in |title= (help)
  13. ^ "Black hole eats star, triggers gamma-ray flash". Cosmos. June 17, 2011. Retrieved 17 June 2011. 

Coordinates: Sky map 16h 44m 49.97s, +57° 34′ 59.7″