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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"

37514 results found.

  1. XRF011130: NEAT Optical Observations
  2. GRB011130 (=XRF011130): Revised Localization of an X-ray
  3. GRB001109, Radio Monitoring
  4. GRB 011121: Errata URL
  5. GRB 011121
  6. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  7. GRB 011121: J-band observations
  8. GRB 011121: NIR observations, host galaxy?
  9. GRB 011121: HST Scheduled
  10. GRB011121: fainter still
  11. Correction: GCN1157 (GRB 011121)
  12. GRB 011121: Radio Observations
  13. GRB 011121 J-Band Astrometry
  14. GRB011121: continued decay
  15. GRB 011121: Detection of Bright IR Counterpart
  16. GRB011121: possible redshift, continued decay
  17. IPN triangulation of GRB011121
  18. BEPPOSAX GRB011121
  19. GRB 011030: TNG K-band observation
  20. XRF011030: Chandra Observations
  21. GRB 011030: K-band observations
  22. GRB 011030 R band observations
  23. GRB 011030 I-band Observation
  24. The X-ray Flash 011030 ('GRB 011030')
  25. Non-triggered burst 011030 ("GRB 011030")
  26. The Radio Afterglow from the X-ray Rich GRB 011030
  27. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  28. GRB 970828: HST Observations of the Host Galaxy
  29. GRB 000131: HST Detection of the Host Galaxy
  30. GRB 970828: HST Observations of the Host Galaxy
  31. GRB010921, optical observation
  32. GRB 011019 optical observation
  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. GRB010921, optical observation at early time
  45. GRB 010921, I-band observations
  46. GRB011019: Optical observations
  47. GRB011019, optical observations
  48. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  49. GRB010921: Spectroscopy of the Host Galaxy
  50. GRB 010921: The afterglow of HETE #1761
  51. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  52. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  53. GRB010923 as seen by BeppoSAX GRBM
  54. GRB010928(=H1770): Localization of a Long GRB by HETE
  55. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  56. GRB010921, negative optical observations
  57. GRB010921 field photometry
  58. GRB010921 Optical Observations
  59. GRB 010921 DPOSS Images Available
  60. IPN triangulation of GRB010921 (=H1761)
  61. H1761: A Bright GRB Detected by HETE
  62. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  63. HETE Trigger #1760 (GRB 010920B?): a new optical source
  64. HETE Trigger #1759 (GRB 010920?) optical observations
  65. GRB001109, Host Galaxy Astrometry
  66. GRB000926, Host Galaxy Observations
  67. GRB001109, Host Galaxy Spectroscopic Observations
  68. Probable SGR or Short Duration GRB Detected by HETE
  69. GRB000926 Host Galaxy Observations
  70. GRB 010222: HST observations -- host galaxy and late-time decay
  71. BeppoSAX/GRBM detection of GRB 010801
  72. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  73. GRB 010222 - WHT BVRI images
  74. GRB 010629 Optical Observations
  75. GRB010629: Optical Observations
  76. GRB010629, optical observations
  77. IPN triangulation of GRB010629
  78. GRB010629: A Burst Localized by HETE
  79. Possible burst from SGR1806-20
  80. IPN detection of SGR1900+14
  81. GRB 00630: Host Galaxy
  82. IPN triangulation of GRB010613
  83. IPN triangulation of GRB010612
  84. HETE Fully-Automated GCN Notices
  85. GRB000301C: Late-time HST/STIS observation
  86. GRB010518: a faint BeppoSAX detection
  87. GRB000418: HST/STIS Second-epoch Observations
  88. GRB010427, Gamma Ray Observations
  89. SGR1900+14
  90. GRB 010222 /corrections to VBT data
  91. Possible precursor to the SGR1900+14 giant burst
  92. IPN Triangulation of the Giant Flare from SGR1900+14
  93. GRB010412, field photometry
  94. GRB 010326b Optical Observations
  95. GRB010412: Optical observations
  96. GRB010412: Optical observations
  97. IPN Triangulation of GRB010412
  98. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  99. BeppoSAX GRB ALERT: GRB010412
  100. GRB Observation Report

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