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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"

37512 results found.

  1. GRB001109, Radio Monitoring
  2. GRB 011121: Errata URL
  3. GRB 011121
  4. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  5. GRB 011121: J-band observations
  6. GRB 011121: NIR observations, host galaxy?
  7. GRB 011121: HST Scheduled
  8. GRB011121: fainter still
  9. Correction: GCN1157 (GRB 011121)
  10. GRB 011121: Radio Observations
  11. GRB 011121 J-Band Astrometry
  12. GRB011121: continued decay
  13. GRB 011121: Detection of Bright IR Counterpart
  14. GRB011121: possible redshift, continued decay
  15. IPN triangulation of GRB011121
  16. BEPPOSAX GRB011121
  17. GRB 011030: TNG K-band observation
  18. XRF011030: Chandra Observations
  19. GRB 011030: K-band observations
  20. GRB 011030 R band observations
  21. GRB 011030 I-band Observation
  22. The X-ray Flash 011030 ('GRB 011030')
  23. Non-triggered burst 011030 ("GRB 011030")
  24. The Radio Afterglow from the X-ray Rich GRB 011030
  25. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  26. GRB 970828: HST Observations of the Host Galaxy
  27. GRB 000131: HST Detection of the Host Galaxy
  28. GRB 970828: HST Observations of the Host Galaxy
  29. GRB010921, optical observation
  30. GRB 011019 optical observation
  31. GRB011019: Subaru Optical Observations
  32. GRB 011030 I-band Observations
  33. GRB 011030 K-band Observations
  34. GRB010921, optical observations
  35. GRB 011030, WSRT radio observations
  36. GRB011030 - further refinement WFC position
  37. GRB 011030, Radio observations
  38. GRB 011030, R-band observations
  39. BeppoSAX ALERT: Possible X-ray rich GRB011030
  40. GRB 010921: Possible supernova component
  41. GRB011019: NEAT Optical Observations
  42. GRB010921, optical observation at early time
  43. GRB 010921, I-band observations
  44. GRB011019: Optical observations
  45. GRB011019, optical observations
  46. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  47. GRB010921: Spectroscopy of the Host Galaxy
  48. GRB 010921: The afterglow of HETE #1761
  49. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  50. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  51. GRB010923 as seen by BeppoSAX GRBM
  52. GRB010928(=H1770): Localization of a Long GRB by HETE
  53. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  54. GRB010921, negative optical observations
  55. GRB010921 field photometry
  56. GRB010921 Optical Observations
  57. GRB 010921 DPOSS Images Available
  58. IPN triangulation of GRB010921 (=H1761)
  59. H1761: A Bright GRB Detected by HETE
  60. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  61. HETE Trigger #1760 (GRB 010920B?): a new optical source
  62. HETE Trigger #1759 (GRB 010920?) optical observations
  63. GRB001109, Host Galaxy Astrometry
  64. GRB000926, Host Galaxy Observations
  65. GRB001109, Host Galaxy Spectroscopic Observations
  66. Probable SGR or Short Duration GRB Detected by HETE
  67. GRB000926 Host Galaxy Observations
  68. GRB 010222: HST observations -- host galaxy and late-time decay
  69. BeppoSAX/GRBM detection of GRB 010801
  70. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  71. GRB 010222 - WHT BVRI images
  72. GRB 010629 Optical Observations
  73. GRB010629: Optical Observations
  74. GRB010629, optical observations
  75. IPN triangulation of GRB010629
  76. GRB010629: A Burst Localized by HETE
  77. Possible burst from SGR1806-20
  78. IPN detection of SGR1900+14
  79. GRB 00630: Host Galaxy
  80. IPN triangulation of GRB010613
  81. IPN triangulation of GRB010612
  82. HETE Fully-Automated GCN Notices
  83. GRB000301C: Late-time HST/STIS observation
  84. GRB010518: a faint BeppoSAX detection
  85. GRB000418: HST/STIS Second-epoch Observations
  86. GRB010427, Gamma Ray Observations
  87. SGR1900+14
  88. GRB 010222 /corrections to VBT data
  89. Possible precursor to the SGR1900+14 giant burst
  90. IPN Triangulation of the Giant Flare from SGR1900+14
  91. GRB010412, field photometry
  92. GRB 010326b Optical Observations
  93. GRB010412: Optical observations
  94. GRB010412: Optical observations
  95. IPN Triangulation of GRB010412
  96. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  97. BeppoSAX GRB ALERT: GRB010412
  98. GRB Observation Report
  99. GRB010324, revised field photometry
  100. REVISED LOCATION OF GRB010326A

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