fbpx
Wikipedia

GRB 970228

December 15, 2023

GRB 970228[2] was the first gamma-ray burst (GRB) for which an afterglow was observed.[3] It was detected on 28 February 1997 at 02:58 UTC. Since 1993, physicists had predicted GRBs to be followed by a lower-energy afterglow (in wavelengths such as radio waves, x-rays, and even visible light), but until this event, GRBs had only been observed in highly luminous bursts of high-energy gamma rays (the most energetic form of electromagnetic radiation); this resulted in large positional uncertainties which left their nature very unclear.

GRB 970228
Event typeGamma-ray burst 
ConstellationOrion 
Right ascension05h 01m 46.7s
Declination+11° 46′ 53.0″[1]
EpochJ2000
Distance8,123,000,000 ly (2.491×109 pc)
Redshift0.695, 0.695 
Total energy output5.2×1044 J
Other designationsGRB 970228
  Related media on Commons
[edit on Wikidata]

The burst had multiple peaks in its light curve and lasted approximately 80 seconds. Peculiarities in the light curve of GRB 970228 suggested that a supernova may have occurred as well. The position of the burst coincided with a galaxy about 8.1 billion light-years[4] away (a redshift of z = 0.695), providing early evidence that GRBs occur well beyond the Milky Way; this was proven decisively two months later with a subsequent burst GRB 970508.

Observations edit

A gamma-ray burst (GRB) is a highly luminous flash of gamma rays, the most energetic form of electromagnetic radiation. GRBs were first detected in 1967 by the Vela satellites, a series of spacecraft designed to detect nuclear explosions.[5]

GRB 970228[2] was detected on 28 February 1997 at 02:58 UTC by the Gamma-Ray Burst Monitor (GRBM) and one of the Wide Field Cameras (WFCs) on board BeppoSAX,[6][7] an Italian–Dutch satellite originally designed to study X-rays.[8] The burst lasted around 80 seconds and had multiple peaks in its light curve.[9] Gamma-ray bursts have very diverse time profiles, and it is not fully understood why some bursts have multiple peaks and some have only one. One possible explanation is that multiple peaks are formed when the source of the gamma-ray burst undergoes precession.[10] Within a few hours, the BeppoSAX team used the X-ray detection to determine the burst's position with an error box—a small area around the specific position to account for the error in the position—of 3 arcminutes.[7] The burst was also detected by the Ulysses space probe.[11]

About one and nine days later, optical images of the error box were taken with the William Herschel Telescope on La Palma; comparison of the images revealed a fading point source located at a right ascension of 05h 01m 46.7s and a declination of +11° 46′ 53.0″, providing the first arcsecond-accuracy localization of any Gamma-ray burst.[1]

Later images after the point source faded revealed a faint galaxy at almost the same position, the presumed host galaxy of the burst; a chance position coincidence was unlikely but possible, so the cosmological origin of GRBs was not conclusive until observations of GRB 970508 about two months later.

Afterglow edit

In 1993, Bohdan Paczyński and James E. Rhoads published an article arguing that, regardless of the type of explosion that causes GRBs, the extreme energetics of GRBs meant that matter from the host body must be ejected at relativistic speeds during the explosion. They predicted that the interaction between the ejecta and interstellar matter would create a shock front. Should this shock front occur in a magnetic field, accelerated electrons in it would emit long-lasting synchrotron radiation in the radio frequencies, a phenomenon that would later be referred to as a radio afterglow.[12] Jonathan Katz later concluded that this lower-energy emission would not be limited to radio waves, but should range in frequency from radio waves to x-rays, including visible light.[13]

The Narrow Field Instruments on board BeppoSAX began making observations of the GRB 970228's position within eight hours of its detection.[9] A transient x-ray source was detected which faded with a power-law slope in the days following the burst. This x-ray afterglow was the first GRB afterglow ever detected.[7] Power-law decays have since been recognized as a common feature in GRB afterglows, although most afterglows decay at differing rates during different phases of their lifetimes.[14]

Optical images were taken of GRB 970228's position on 1 and 8 March using the William Herschel Telescope and the Isaac Newton Telescope. Comparison of the images revealed an object which had decreased in luminosity in both visible light and infrared light.[1] This was the burst's optical afterglow. Deeper follow-up observations using the New Technology Telescope showed that the afterglow coincided with a distant, small galaxy: the first evidence of the extragalactic, cosmological nature of Gamma-ray bursts.[15][16] After the gamma-ray bursts itself had faded away, very deep observations taken with the Keck telescopes showed the underlying galaxy to have a redshift of 0.695. The predicted radio afterglow was never detected for this burst.[17] At the time of this burst's discovery, GRBs were believed to emit radiation isotropically. The afterglows from this burst and several others—such as GRB 970508 and GRB 971214—provided early evidence that GRBs emit radiation in collimated jets, a characteristic which lowers the total energy output of a burst by several orders of magnitude.[18]

Supernova relation edit

 
Artist's illustration showing the life of a massive star as it goes supernova, collapses into a black hole, and emits a gamma-ray burst along its axis of rotation Credit: Nicolle Rager Fuller/NSF

Daniel Reichart of the University of Chicago and Titus Galama of the University of Amsterdam independently analyzed GRB 970228's optical light curve, both concluding that the host object may have undergone a supernova explosion several weeks before the gamma-ray burst occurred.[19][20]

Galama analyzed the light curve of the burst and found that its luminosity decayed at different rates at different times. The luminosity decayed more slowly between March 6 and April 7 than it did before and after these dates. Galama concluded that the earlier light curve had been dominated by the burst itself, whereas the later light curve was produced by the underlying Type Ic supernova.[21] Reichart noted that the late afterglow was redder than the early afterglow, an observation which conflicted with the then-preferred relativistic fireball model for the gamma-ray burst emission mechanism. He also observed that the only GRB with a similar temporal profile was GRB 980326,[20] for which a supernova relation had already been proposed by Joshua Bloom.[22]

An alternative explanation for the light curves of GRB 970228 and GRB 980326 involved dust echoes. Although GRB 980326 did not provide enough information to definitively rule out this explanation, Reichart showed that the light curve of GRB 970228 could only have been caused by a supernova.[23] Definitive evidence linking gamma-ray bursts and supernovae was eventually found in the spectrum of GRB 020813[24] and the afterglow of GRB 030329.[25] However, supernova-like features only become apparent in the weeks following a burst, leaving the possibility that very early luminosity variations could be explained by dust echoes.[26]

Host galaxy edit

During the night between 12 and 13 March, Jorge Melnick made observations of the region with the New Technology Telescope. He discovered a faint nebular patch at the burst's position, almost certainly a distant galaxy. Although there was a remote chance that the burst and this galaxy were unrelated, their positional coincidence provided strong evidence that GRBs occur in distant galaxies rather than within the Milky Way.[27] This conclusion was later supported by observations of GRB 970508, the first burst to have its redshift determined.[28]

The position of the burst's afterglow was measurably offset from the centroid of the host galaxy, effectively ruling out the possibility that the burst originated in an active galactic nucleus. The redshift of the galaxy was later determined to be z = 0.695,[17] which corresponds to a distance of approximately 8.123×109 ly.[4] At this distance, the burst would have released a total of 5.2×1044 J assuming isotropic emission.[29]

Notes edit

  1. ^ a b c Groot 12 March 1997
  2. ^ a b "GRB" indicates that the event was a gamma-ray burst, and the numbers follow a YYMMDD format corresponding to the date on which the burst occurred: 28 February 1997.
  3. ^ Schilling 2002, p. 101
  4. ^ a b Converting of the redshift into the distance done by on-line tools:
    Wright, Edward L. (9 May 2008). "Ned Wright's Javascript Cosmology Calculator". UCLA Division of Astronomy & Astrophysics. Retrieved 2010-06-11.
  5. ^ Schilling 2002, pp. 12–16
  6. ^ Varendoff 2001, p. 381
  7. ^ a b c Costa 1997b
  8. ^ Schilling 2002, pp. 58–60
  9. ^ a b Costa 1997a
  10. ^ Zwart 2001
  11. ^ Hurley 1997
  12. ^ Paczyński 1993
  13. ^ Katz 1994
  14. ^ Panaitescu 2007, §2
  15. ^ Groot 14 March 1997
  16. ^ Van Paradijs et al., 1997
  17. ^ a b Bloom 2001
  18. ^ Huang 2002
  19. ^ Schilling 2002, p. 173
  20. ^ a b Reichart 1999
  21. ^ Galama 2000
  22. ^ Bloom 1999
  23. ^ Reichart 2001
  24. ^ Butler 2003
  25. ^ Stanek 2003
  26. ^ Moran 2005
  27. ^ Schilling 2002, p. 102
  28. ^ Reichart 1998
  29. ^ Djorgovski 1999

References edit

  • Bloom, J. S.; Djorgovski, S. G.; Kulkarni, S. R. (2001). "The redshift and the ordinary host galaxy of GRB 970228". Astrophysical Journal. 554 (2): 678–683. arXiv:astro-ph/0007244. Bibcode:2001ApJ...554..678B. doi:10.1086/321398. S2CID 16648604.
  • Bloom, J. S.; Kulkarni, S. R.; Djorgovski, S. G.; Eichelberger, A. C.; Côté, P.; Blakeslee, J. P.; Odewahn, S. C.; Harrison, F. A.; Frail, D. A.; Filippenko, A. V.; Leonard, D. C.; Riess, A. G.; Spinrad, H.; Stern, D.; Bunker, A.; Dey, A.; Grossan, B.; Perlmutter, S.; Knop, R. A.; Hook, I. M.; Feroci, M. (30 September 1999). "The unusual afterglow of the γ-ray burst of 26 March 1998 as evidence for a supernova connection". Nature. 401 (6752): 453–456. arXiv:astro-ph/9905301. Bibcode:1999Natur.401..453B. doi:10.1038/46744. S2CID 205058997.
  • Butler, Nathaniel R.; Marshall, Herman L.; Ricker, George R.; Vanderspek, Roland K.; Ford, Peter G.; Crew, Geoffrey B.; Lamb, Donald Q.; Jernigan, J. Garrett (10 November 2003). "The X-ray Afterglows of GRB 020813 and GRB 021004 with Chandra HETGS: Possible Evidence for a Supernova prior to GRB 020813". The Astrophysical Journal. 597 (2): 1010–1016. arXiv:astro-ph/0303539. Bibcode:2003ApJ...597.1010B. doi:10.1086/378511. S2CID 6171688.
  • Costa, E. et al. (1997a) "IAU Circular 6572: GRB 970228; 1997aa". International Astronomical Union.
  • Costa, E.; Frontera, F.; Heise, J.; Feroci, M.; In 't Zand, J.; Fiore, F.; Cinti, M. N.; Dal Fiume, D.; Nicastro, L.; Orlandini, M.; Palazzi, E.; Rapisarda, M.; Zavattini, G.; Jager, R.; Parmar, A.; Owens, A.; Molendi, S.; Cusumano, G.; MacCarone, M. C.; Giarrusso, S.; Coletta, A.; Antonelli, L. A.; Giommi, P.; Muller, J. M.; Piro, L.; Butler, R. C. (1997b). "Discovery of an X-ray afterglow associated with the γ-ray burst of 28 February 1997". Nature. 387 (6635): 783–785. arXiv:astro-ph/9706065. Bibcode:1997Natur.387..783C. doi:10.1038/42885. S2CID 9505956.
  • Djorgovski, George (3 May 1999). "GRB 970228: Redshift and properties of the host galaxy". GCN Circulars. 289: 1. Bibcode:1999GCN...289....1D.
  • Esin, A. A.; Blandford, R. (2000). "Dust Echoes from Gamma-Ray Bursts". Astrophysical Journal. 534 (2): L151–L154. arXiv:astro-ph/0003415. Bibcode:2000ApJ...534L.151E. doi:10.1086/312670. PMID 10813670. S2CID 14962603.
  • Fox, D. W. et al. (6 May 1997) "IAU Circular 6643: GRB 970228; 1997by". International Astronomical Union.
  • Galama, T. J.; Tanvir, N.; Vreeswijk, P. M.; Wijers, R. A. M. J.; Groot, P. J.; Rol, E.; Van Paradijs, J.; Kouveliotou, C.; Fruchter, A. S.; Masetti, N.; Pedersen, H.; Margon, B.; Deutsch, E. W.; Metzger, M.; Armus, L.; Klose, S.; Stecklum, B. (10 June 2000). "Evidence for a Supernova in Reanalyzed Optical and Near-Infrared Images of GRB 970228". The Astrophysical Journal. 536 (1): 185–194. arXiv:astro-ph/9907264. Bibcode:2000ApJ...536..185G. doi:10.1086/308909. S2CID 34690851.
  • Groot, P. J. et al. (12 March 1997) "IAU Circular 6584: GRB 970228". International Astronomical Union.
  • Groot, P. J. et al. (14 March 1997) "IAU Circular 6588: GRB 970228". International Astronomical Union.
  • Huang, Yong-feng; Tan, Chang-yi; Dai, Zi-gao; Lu, Tan (2002). "Are Gamma-ray Bursts Due to Isotropic Fireballs or Cylindrical Jets?". Chinese Astronomy and Astrophysics. 26 (4): 414–423. Bibcode:2002ChA&A..26..414H. doi:10.1016/S0275-1062(02)00092-9.
  • Hurley, K. et al. (8 March 1997) "IAU Circular 6578: GRB 970228". International Astronomical Union. Retrieved on 23 February 2010.
  • Katz, J. I. (1994). "Low-Frequency Spectra of Gamma-Ray Bursts". Astrophysical Journal. 432 (2): L107–L109. arXiv:astro-ph/9312034. Bibcode:1994ApJ...432L.107K. doi:10.1086/187523. S2CID 15787149.
  • Moran, Jane A.; Reichart, Daniel E. (10 October 2005). "Gamma-Ray Burst Dust Echoes Revisited: Expectations at Early Times". Astrophysical Journal. 632 (1): 438–442. arXiv:astro-ph/0409390. Bibcode:2005ApJ...632..438M. doi:10.1086/432634. S2CID 7506509.
  • Paczyński, Bohdan; Rhoads, James E. (1993). "Radio Transients from Gamma-Ray Bursters". Astrophysical Journal. 418: L5–L8. arXiv:astro-ph/9307024. Bibcode:1993ApJ...418L...5P. doi:10.1086/187102. S2CID 17567870.
  • Panaitescu, A. (15 May 2007). "Decay phases of Swift X-ray afterglows and the forward-shock model". Philosophical Transactions of the Royal Society A. 365 (1854): 1197–1205. Bibcode:2007RSPTA.365.1197P. doi:10.1098/rsta.2006.1985. PMID 17293326. S2CID 12425394.
  • Pedichini, F. et al. (22 April 1997) "IAU Circular 6635: GRB 970228; C/1995 O1". International Astronomical Union.
  • Reichart, Daniel E. (19 February 1998). "The Redshift of GRB 970508". Astrophysical Journal Letters. University of Chicago. 495 (2): L99–L101. arXiv:astro-ph/9712134. Bibcode:1998ApJ...495L..99R. doi:10.1086/311222. S2CID 119394440.
  • Reichart, Daniel E. (1999). "GRB 970228 Revisited: Evidence for a Supernova in the Light Curve and Late Spectral Energy Distribution of the Afterglow". Astrophysical Journal. 521 (2): L111–L115. arXiv:astro-ph/9906079. Bibcode:1999ApJ...521L.111R. doi:10.1086/312203. S2CID 7344802.
  • Reichart, Daniel E. (2001). "Light Curves and Spectra of Dust Echoes from Gamma-Ray Bursts and Their Afterglows: Continued Evidence That GRB 970228 Is Associated with a Supernova". Astrophysical Journal. 554 (2): 649–659. arXiv:astro-ph/0012091. Bibcode:2001ApJ...554..643R. doi:10.1086/321428. S2CID 7492485.
  • Schilling, Govert (2002). Flash! The Hunt for the Biggest Explosions in the Universe. Cambridge: Cambridge University Press. ISBN 0-521-80053-6.
  • Stanek, Krzysztof Z.; Matheson, T.; Garnavich, P. M.; Martini, P.; Berlind, P.; Caldwell, N.; Challis, P.; Brown, W. R.; et al. (12 June 2003). "Spectroscopic Discovery of the Supernova 2003dh Associated with GRB0303291". Astrophysical Journal. 591 (1): L17–L20. arXiv:astro-ph/0304173. Bibcode:2003ApJ...591L..17S. doi:10.1086/376976. S2CID 2561943.
  • van Paradijs, J.; Groot, P. J.; Galama, T.; Kouveliotou, C.; Strom, R. G.; Telting, J.; Rutten, R. G. M.; Fishman, G. J.; Meegan, C. A.; Pettini, M.; Tanvir, N.; Bloom, J.; Pedersen, H.; Nørdgaard-Nielsen, H. U.; Linden-Vørnle, M.; Melnick, J.; Van Der Steene, G.; Bremer, M.; Naber, R.; Heise, J.; In't Zand, J.; Costa, E.; Feroci, M.; Piro, L.; Frontera, F.; Zavattini, G.; Nicastro, L.; Palazzi, E.; Bennet, K.; et al. (1997). "Transient optical emission from the error box of the γ-ray burst of 28 February 1997" (PDF). Nature. 386 (6626): 686–689. Bibcode:1997Natur.386..686V. doi:10.1038/386686a0. S2CID 4248753.
  • Varendoff, Martin (2001). "Gamma-Ray Bursts". In Volken Schönfelder (ed.). The Universe in Gamma Rays. Berlin: Springer-Verlag. ISBN 978-3-540-67874-8.
  • Zwart, Simon F. Portegies; Totani, Tomonori (17 August 2001). "Precessing jets interacting with interstellar material as the origin for the light curves of gamma-ray bursts". Monthly Notices of the Royal Astronomical Society. 328 (3): 951–957. arXiv:astro-ph/0006143. Bibcode:2001MNRAS.328..951P. doi:10.1046/j.1365-8711.2001.04913.x. S2CID 9509367.

External links edit

  • Gamma-ray Burst 970228
  • BeppoSAX follow-up observations of the region of the Gamma-ray burst GRB 970228 2011-03-03 at the Wayback Machine

December 15, 2023
970228, first, gamma, burst, which, afterglow, observed, detected, february, 1997, since, 1993, physicists, predicted, grbs, followed, lower, energy, afterglow, wavelengths, such, radio, waves, rays, even, visible, light, until, this, event, grbs, only, been, . GRB 970228 2 was the first gamma ray burst GRB for which an afterglow was observed 3 It was detected on 28 February 1997 at 02 58 UTC Since 1993 physicists had predicted GRBs to be followed by a lower energy afterglow in wavelengths such as radio waves x rays and even visible light but until this event GRBs had only been observed in highly luminous bursts of high energy gamma rays the most energetic form of electromagnetic radiation this resulted in large positional uncertainties which left their nature very unclear GRB 970228Event typeGamma ray burst ConstellationOrion Right ascension05h 01m 46 7sDeclination 11 46 53 0 1 EpochJ2000Distance8 123 000 000 ly 2 491 109 pc Redshift0 695 0 695 Total energy output5 2 1044 JOther designationsGRB 970228 Related media on Commons edit on Wikidata The burst had multiple peaks in its light curve and lasted approximately 80 seconds Peculiarities in the light curve of GRB 970228 suggested that a supernova may have occurred as well The position of the burst coincided with a galaxy about 8 1 billion light years 4 away a redshift of z 0 695 providing early evidence that GRBs occur well beyond the Milky Way this was proven decisively two months later with a subsequent burst GRB 970508 Contents 1 Observations 2 Afterglow 3 Supernova relation 4 Host galaxy 5 Notes 6 References 7 External linksObservations editA gamma ray burst GRB is a highly luminous flash of gamma rays the most energetic form of electromagnetic radiation GRBs were first detected in 1967 by the Vela satellites a series of spacecraft designed to detect nuclear explosions 5 GRB 970228 2 was detected on 28 February 1997 at 02 58 UTC by the Gamma Ray Burst Monitor GRBM and one of the Wide Field Cameras WFCs on board BeppoSAX 6 7 an Italian Dutch satellite originally designed to study X rays 8 The burst lasted around 80 seconds and had multiple peaks in its light curve 9 Gamma ray bursts have very diverse time profiles and it is not fully understood why some bursts have multiple peaks and some have only one One possible explanation is that multiple peaks are formed when the source of the gamma ray burst undergoes precession 10 Within a few hours the BeppoSAX team used the X ray detection to determine the burst s position with an error box a small area around the specific position to account for the error in the position of 3 arcminutes 7 The burst was also detected by the Ulysses space probe 11 About one and nine days later optical images of the error box were taken with the William Herschel Telescope on La Palma comparison of the images revealed a fading point source located at a right ascension of 05h 01m 46 7s and a declination of 11 46 53 0 providing the first arcsecond accuracy localization of any Gamma ray burst 1 Later images after the point source faded revealed a faint galaxy at almost the same position the presumed host galaxy of the burst a chance position coincidence was unlikely but possible so the cosmological origin of GRBs was not conclusive until observations of GRB 970508 about two months later Afterglow editIn 1993 Bohdan Paczynski and James E Rhoads published an article arguing that regardless of the type of explosion that causes GRBs the extreme energetics of GRBs meant that matter from the host body must be ejected at relativistic speeds during the explosion They predicted that the interaction between the ejecta and interstellar matter would create a shock front Should this shock front occur in a magnetic field accelerated electrons in it would emit long lasting synchrotron radiation in the radio frequencies a phenomenon that would later be referred to as a radio afterglow 12 Jonathan Katz later concluded that this lower energy emission would not be limited to radio waves but should range in frequency from radio waves to x rays including visible light 13 The Narrow Field Instruments on board BeppoSAX began making observations of the GRB 970228 s position within eight hours of its detection 9 A transient x ray source was detected which faded with a power law slope in the days following the burst This x ray afterglow was the first GRB afterglow ever detected 7 Power law decays have since been recognized as a common feature in GRB afterglows although most afterglows decay at differing rates during different phases of their lifetimes 14 Optical images were taken of GRB 970228 s position on 1 and 8 March using the William Herschel Telescope and the Isaac Newton Telescope Comparison of the images revealed an object which had decreased in luminosity in both visible light and infrared light 1 This was the burst s optical afterglow Deeper follow up observations using the New Technology Telescope showed that the afterglow coincided with a distant small galaxy the first evidence of the extragalactic cosmological nature of Gamma ray bursts 15 16 After the gamma ray bursts itself had faded away very deep observations taken with the Keck telescopes showed the underlying galaxy to have a redshift of 0 695 The predicted radio afterglow was never detected for this burst 17 At the time of this burst s discovery GRBs were believed to emit radiation isotropically The afterglows from this burst and several others such as GRB 970508 and GRB 971214 provided early evidence that GRBs emit radiation in collimated jets a characteristic which lowers the total energy output of a burst by several orders of magnitude 18 Supernova relation edit nbsp Artist s illustration showing the life of a massive star as it goes supernova collapses into a black hole and emits a gamma ray burst along its axis of rotation Credit Nicolle Rager Fuller NSFDaniel Reichart of the University of Chicago and Titus Galama of the University of Amsterdam independently analyzed GRB 970228 s optical light curve both concluding that the host object may have undergone a supernova explosion several weeks before the gamma ray burst occurred 19 20 Galama analyzed the light curve of the burst and found that its luminosity decayed at different rates at different times The luminosity decayed more slowly between March 6 and April 7 than it did before and after these dates Galama concluded that the earlier light curve had been dominated by the burst itself whereas the later light curve was produced by the underlying Type Ic supernova 21 Reichart noted that the late afterglow was redder than the early afterglow an observation which conflicted with the then preferred relativistic fireball model for the gamma ray burst emission mechanism He also observed that the only GRB with a similar temporal profile was GRB 980326 20 for which a supernova relation had already been proposed by Joshua Bloom 22 An alternative explanation for the light curves of GRB 970228 and GRB 980326 involved dust echoes Although GRB 980326 did not provide enough information to definitively rule out this explanation Reichart showed that the light curve of GRB 970228 could only have been caused by a supernova 23 Definitive evidence linking gamma ray bursts and supernovae was eventually found in the spectrum of GRB 020813 24 and the afterglow of GRB 030329 25 However supernova like features only become apparent in the weeks following a burst leaving the possibility that very early luminosity variations could be explained by dust echoes 26 Host galaxy editDuring the night between 12 and 13 March Jorge Melnick made observations of the region with the New Technology Telescope He discovered a faint nebular patch at the burst s position almost certainly a distant galaxy Although there was a remote chance that the burst and this galaxy were unrelated their positional coincidence provided strong evidence that GRBs occur in distant galaxies rather than within the Milky Way 27 This conclusion was later supported by observations of GRB 970508 the first burst to have its redshift determined 28 The position of the burst s afterglow was measurably offset from the centroid of the host galaxy effectively ruling out the possibility that the burst originated in an active galactic nucleus The redshift of the galaxy was later determined to be z 0 695 17 which corresponds to a distance of approximately 8 123 109 ly 4 At this distance the burst would have released a total of 5 2 1044 J assuming isotropic emission 29 Notes edit a b c Groot 12 March 1997 a b GRB indicates that the event was a gamma ray burst and the numbers follow a YYMMDD format corresponding to the date on which the burst occurred 28 February 1997 Schilling 2002 p 101 a b Converting of the redshift into the distance done by on line tools Wright Edward L 9 May 2008 Ned Wright s Javascript Cosmology Calculator UCLA Division of Astronomy amp Astrophysics Retrieved 2010 06 11 Schilling 2002 pp 12 16 Varendoff 2001 p 381 a b c Costa 1997b Schilling 2002 pp 58 60 a b Costa 1997a Zwart 2001 Hurley 1997 Paczynski 1993 Katz 1994 Panaitescu 2007 2 Groot 14 March 1997 Van Paradijs et al 1997 a b Bloom 2001 Huang 2002 Schilling 2002 p 173 a b Reichart 1999 Galama 2000 Bloom 1999 Reichart 2001 Butler 2003 Stanek 2003 Moran 2005 Schilling 2002 p 102 Reichart 1998 Djorgovski 1999References editBloom J S Djorgovski S G Kulkarni S R 2001 The redshift and the ordinary host galaxy of GRB 970228 Astrophysical Journal 554 2 678 683 arXiv astro ph 0007244 Bibcode 2001ApJ 554 678B doi 10 1086 321398 S2CID 16648604 Bloom J S Kulkarni S R Djorgovski S G Eichelberger A C Cote P Blakeslee J P Odewahn S C Harrison F A Frail D A Filippenko A V Leonard D C Riess A G Spinrad H Stern D Bunker A Dey A Grossan B Perlmutter S Knop R A Hook I M Feroci M 30 September 1999 The unusual afterglow of the g ray burst of 26 March 1998 as evidence for a supernova connection Nature 401 6752 453 456 arXiv astro ph 9905301 Bibcode 1999Natur 401 453B doi 10 1038 46744 S2CID 205058997 Butler Nathaniel R Marshall Herman L Ricker George R Vanderspek Roland K Ford Peter G Crew Geoffrey B Lamb Donald Q Jernigan J Garrett 10 November 2003 The X ray Afterglows of GRB 020813 and GRB 021004 with Chandra HETGS Possible Evidence for a Supernova prior to GRB 020813 The Astrophysical Journal 597 2 1010 1016 arXiv astro ph 0303539 Bibcode 2003ApJ 597 1010B doi 10 1086 378511 S2CID 6171688 Costa E et al 1997a IAU Circular 6572 GRB 970228 1997aa International Astronomical Union Costa E Frontera F Heise J Feroci M In t Zand J Fiore F Cinti M N Dal Fiume D Nicastro L Orlandini M Palazzi E Rapisarda M Zavattini G Jager R Parmar A Owens A Molendi S Cusumano G MacCarone M C Giarrusso S Coletta A Antonelli L A Giommi P Muller J M Piro L Butler R C 1997b Discovery of an X ray afterglow associated with the g ray burst of 28 February 1997 Nature 387 6635 783 785 arXiv astro ph 9706065 Bibcode 1997Natur 387 783C doi 10 1038 42885 S2CID 9505956 Djorgovski George 3 May 1999 GRB 970228 Redshift and properties of the host galaxy GCN Circulars 289 1 Bibcode 1999GCN 289 1D Esin A A Blandford R 2000 Dust Echoes from Gamma Ray Bursts Astrophysical Journal 534 2 L151 L154 arXiv astro ph 0003415 Bibcode 2000ApJ 534L 151E doi 10 1086 312670 PMID 10813670 S2CID 14962603 Fox D W et al 6 May 1997 IAU Circular 6643 GRB 970228 1997by International Astronomical Union Galama T J Tanvir N Vreeswijk P M Wijers R A M J Groot P J Rol E Van Paradijs J Kouveliotou C Fruchter A S Masetti N Pedersen H Margon B Deutsch E W Metzger M Armus L Klose S Stecklum B 10 June 2000 Evidence for a Supernova in Reanalyzed Optical and Near Infrared Images of GRB 970228 The Astrophysical Journal 536 1 185 194 arXiv astro ph 9907264 Bibcode 2000ApJ 536 185G doi 10 1086 308909 S2CID 34690851 Groot P J et al 12 March 1997 IAU Circular 6584 GRB 970228 International Astronomical Union Groot P J et al 14 March 1997 IAU Circular 6588 GRB 970228 International Astronomical Union Huang Yong feng Tan Chang yi Dai Zi gao Lu Tan 2002 Are Gamma ray Bursts Due to Isotropic Fireballs or Cylindrical Jets Chinese Astronomy and Astrophysics 26 4 414 423 Bibcode 2002ChA amp A 26 414H doi 10 1016 S0275 1062 02 00092 9 Hurley K et al 8 March 1997 IAU Circular 6578 GRB 970228 International Astronomical Union Retrieved on 23 February 2010 Katz J I 1994 Low Frequency Spectra of Gamma Ray Bursts Astrophysical Journal 432 2 L107 L109 arXiv astro ph 9312034 Bibcode 1994ApJ 432L 107K doi 10 1086 187523 S2CID 15787149 Moran Jane A Reichart Daniel E 10 October 2005 Gamma Ray Burst Dust Echoes Revisited Expectations at Early Times Astrophysical Journal 632 1 438 442 arXiv astro ph 0409390 Bibcode 2005ApJ 632 438M doi 10 1086 432634 S2CID 7506509 Paczynski Bohdan Rhoads James E 1993 Radio Transients from Gamma Ray Bursters Astrophysical Journal 418 L5 L8 arXiv astro ph 9307024 Bibcode 1993ApJ 418L 5P doi 10 1086 187102 S2CID 17567870 Panaitescu A 15 May 2007 Decay phases of Swift X ray afterglows and the forward shock model Philosophical Transactions of the Royal Society A 365 1854 1197 1205 Bibcode 2007RSPTA 365 1197P doi 10 1098 rsta 2006 1985 PMID 17293326 S2CID 12425394 Pedichini F et al 22 April 1997 IAU Circular 6635 GRB 970228 C 1995 O1 International Astronomical Union Reichart Daniel E 19 February 1998 The Redshift of GRB 970508 Astrophysical Journal Letters University of Chicago 495 2 L99 L101 arXiv astro ph 9712134 Bibcode 1998ApJ 495L 99R doi 10 1086 311222 S2CID 119394440 Reichart Daniel E 1999 GRB 970228 Revisited Evidence for a Supernova in the Light Curve and Late Spectral Energy Distribution of the Afterglow Astrophysical Journal 521 2 L111 L115 arXiv astro ph 9906079 Bibcode 1999ApJ 521L 111R doi 10 1086 312203 S2CID 7344802 Reichart Daniel E 2001 Light Curves and Spectra of Dust Echoes from Gamma Ray Bursts and Their Afterglows Continued Evidence That GRB 970228 Is Associated with a Supernova Astrophysical Journal 554 2 649 659 arXiv astro ph 0012091 Bibcode 2001ApJ 554 643R doi 10 1086 321428 S2CID 7492485 Schilling Govert 2002 Flash The Hunt for the Biggest Explosions in the Universe Cambridge Cambridge University Press ISBN 0 521 80053 6 Stanek Krzysztof Z Matheson T Garnavich P M Martini P Berlind P Caldwell N Challis P Brown W R et al 12 June 2003 Spectroscopic Discovery of the Supernova 2003dh Associated with GRB0303291 Astrophysical Journal 591 1 L17 L20 arXiv astro ph 0304173 Bibcode 2003ApJ 591L 17S doi 10 1086 376976 S2CID 2561943 van Paradijs J Groot P J Galama T Kouveliotou C Strom R G Telting J Rutten R G M Fishman G J Meegan C A Pettini M Tanvir N Bloom J Pedersen H Nordgaard Nielsen H U Linden Vornle M Melnick J Van Der Steene G Bremer M Naber R Heise J In t Zand J Costa E Feroci M Piro L Frontera F Zavattini G Nicastro L Palazzi E Bennet K et al 1997 Transient optical emission from the error box of the g ray burst of 28 February 1997 PDF Nature 386 6626 686 689 Bibcode 1997Natur 386 686V doi 10 1038 386686a0 S2CID 4248753 Varendoff Martin 2001 Gamma Ray Bursts In Volken Schonfelder ed The Universe in Gamma Rays Berlin Springer Verlag ISBN 978 3 540 67874 8 Zwart Simon F Portegies Totani Tomonori 17 August 2001 Precessing jets interacting with interstellar material as the origin for the light curves of gamma ray bursts Monthly Notices of the Royal Astronomical Society 328 3 951 957 arXiv astro ph 0006143 Bibcode 2001MNRAS 328 951P doi 10 1046 j 1365 8711 2001 04913 x S2CID 9509367 External links editGamma ray Burst 970228 BeppoSAX follow up observations of the region of the Gamma ray burst GRB 970228 Archived 2011 03 03 at the Wayback Machine Retrieved from https en wikipedia org w index php title GRB 970228 amp oldid 1174744785, wikipedia, wiki, book, books, library,

article

, read, download, free, free download, mp3, video, mp4, 3gp, jpg, jpeg, gif, png, picture, music, song, movie, book, game, games.