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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

42786 results found.

  1. GRB 011121: HST Scheduled
  2. GRB011121: fainter still
  3. Correction: GCN1157 (GRB 011121)
  4. GRB011121: UBRI Observations
  5. GRB011121
  6. GRB 011121: Radio Observations
  7. GRB 011121 J-Band Astrometry
  8. GRB011121: continued decay
  9. GRB 011121: Detection of Bright IR Counterpart
  10. GRB011121: possible redshift, continued decay
  11. GRB011121: fading behavior
  12. GRB011121: possible optical counterpart
  13. IPN triangulation of GRB011121
  14. BEPPOSAX GRB011121
  15. GRB 011030: TNG K-band observation
  16. XRF011030: J and K band observations
  17. GRB011030, optical observation
  18. XRF011030: Chandra Observations
  19. GRB 011030: K-band observations
  20. GRB011030: Z-band observations
  21. GRB 011030 R band observations
  22. GRB 011030 I-band Observation
  23. The X-ray Flash 011030 ('GRB 011030')
  24. Non-triggered burst 011030 ("GRB 011030")
  25. The Radio Afterglow from the X-ray Rich GRB 011030
  26. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  27. GRB 970828: HST Observations of the Host Galaxy
  28. GRB 000131: HST Detection of the Host Galaxy
  29. GRB 970828: HST Observations of the Host Galaxy
  30. GRB010921, optical observation
  31. GRB 011019 optical observation
  32. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  33. GRB011019: Subaru Optical Observations
  34. GRB 011030 I-band Observations
  35. GRB 011030 K-band Observations
  36. GRB010921, optical observations
  37. GRB 011030, WSRT radio observations
  38. GRB011030 - further refinement WFC position
  39. GRB 011030, Radio observations
  40. GRB 011030, R-band observations
  41. BeppoSAX ALERT: Possible X-ray rich GRB011030
  42. GRB 010921: Possible supernova component
  43. GRB011019: NEAT Optical Observations
  44. GRB011019: ROTSE-III optical observations
  45. GRB010921, optical observation at early time
  46. GRB011019: Optical observations
  47. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  48. GRB010921: Spectroscopy of the Host Galaxy
  49. GRB 010921: The afterglow of HETE #1761
  50. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  51. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  52. GRB010923 as seen by BeppoSAX GRBM
  53. GRB010928(=H1770): Localization of a Long GRB by HETE
  54. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  55. GRB010921, negative optical observations
  56. GRB010921 field photometry
  57. GRB010921 Optical Observations
  58. GRB 010921 DPOSS Images Available
  59. IPN triangulation of GRB010921 (=H1761)
  60. H1761: A Bright GRB Detected by HETE
  61. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  62. HETE Trigger #1760 (GRB 010920B?): a new optical source
  63. HETE Trigger #1759 (GRB 010920?) optical observations
  64. GRB001109, Host Galaxy Astrometry
  65. GRB000926, Host Galaxy Observations
  66. GRB001109, Host Galaxy Spectroscopic Observations
  67. Probable SGR or Short Duration GRB Detected by HETE
  68. GRB000926 Host Galaxy Observations
  69. GRB 010222: HST observations -- host galaxy and late-time decay
  70. BeppoSAX/GRBM detection of GRB 010801
  71. GCN and HETE status
  72. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  73. BeppoSAX/GRBM detection of GRB010728
  74. GRB 010222 - WHT BVRI images
  75. SGR1900+14 burst seen by HETE: BeppoSAX data
  76. GRB010629: Optical Observations
  77. SGR1900+14: High Fluence Burst Localized by HETE
  78. GRB010629, optical observations
  79. IPN triangulation of GRB010629
  80. GRB010629: A Burst Localized by HETE
  81. SGR1900+14: Second Burst Localized by HETE
  82. SGR1900+14: A Burst Localized by HETE
  83. Possible burst from SGR1806-20
  84. IPN detection of SGR1900+14
  85. SGR1806-20: A Second, Intense Burst Localized by HETE
  86. GRB 00630: Host Galaxy
  87. SGR1806-20: Localization by HETE
  88. IPN triangulation of GRB010613
  89. IPN triangulation of GRB010612
  90. HETE Fully-Automated GCN Notices
  91. GRB000301C: Late-time HST/STIS observation
  92. GRB010518: a faint BeppoSAX detection
  93. GRB000418: HST/STIS Second-epoch Observations
  94. X-ray precursors to the large flare from SGR 1900+14
  95. GRB010214, optical observations
  96. GRB010427, Gamma Ray Observations
  97. SGR 1900+14: No evidence of extended X-ray emission
  98. SGR 1900+14 : RXTE observations
  99. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  100. SGR1900+14 - correction

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