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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"

45451 results found.

  1. GRB 011121
  2. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  3. GRB 011121: J-band observations
  4. GRB 011121: NIR observations, host galaxy?
  5. GRB010921 - Milagro GeV/TeV Observations
  6. GRB 011121: HST Scheduled
  7. GRB011121: fainter still
  8. Correction: GCN1157 (GRB 011121)
  9. GRB011121: UBRI Observations
  10. GRB011121
  11. GRB 011121: Radio Observations
  12. GRB 011121 J-Band Astrometry
  13. GRB011121: continued decay
  14. GRB 011121: Detection of Bright IR Counterpart
  15. GRB011121: possible redshift, continued decay
  16. GRB011121: fading behavior
  17. GRB011121: possible optical counterpart
  18. IPN triangulation of GRB011121
  19. BEPPOSAX GRB011121
  20. GRB 011030: TNG K-band observation
  21. XRF011030: J and K band observations
  22. GRB011030, optical observation
  23. XRF011030: Chandra Observations
  24. GRB 011030: K-band observations
  25. GRB011030: Z-band observations
  26. GRB 011030 R band observations
  27. GRB 011030 I-band Observation
  28. The X-ray Flash 011030 ('GRB 011030')
  29. Non-triggered burst 011030 ("GRB 011030")
  30. The Radio Afterglow from the X-ray Rich GRB 011030
  31. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  32. GRB 970828: HST Observations of the Host Galaxy
  33. GRB 000131: HST Detection of the Host Galaxy
  34. GRB 970828: HST Observations of the Host Galaxy
  35. GRB010921, optical observation
  36. GRB 011019 optical observation
  37. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  38. GRB011019: Subaru Optical Observations
  39. GRB 011030 I-band Observations
  40. GRB 011030 K-band Observations
  41. GRB010921, optical observations
  42. GRB 011030, WSRT radio observations
  43. GRB011030 - further refinement WFC position
  44. GRB 011030, Radio observations
  45. GRB011030: radio search
  46. GRB 011030, R-band observations
  47. X-ray rich GRB011030: BeppoSAX refined positions
  48. BeppoSAX ALERT: Possible X-ray rich GRB011030
  49. GRB 010921: Possible supernova component
  50. GRB011019: NEAT Optical Observations
  51. GRB011019: ROTSE-III optical observations
  52. GRB010921, optical observation at early time
  53. GRB 010921, I-band observations
  54. GRB011019: Optical observations
  55. GRB011019, optical observations
  56. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  57. GRB010921: Spectroscopy of the Host Galaxy
  58. GRB 010921: The afterglow of HETE #1761
  59. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  60. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  61. GRB010923 as seen by BeppoSAX GRBM
  62. GRB010928(=H1770): Localization of a Long GRB by HETE
  63. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  64. GRB010921, negative optical observations
  65. GRB010921 field photometry
  66. GRB010921 Optical Observations
  67. GRB 010921 DPOSS Images Available
  68. IPN triangulation of GRB010921 (=H1761)
  69. H1761: A Bright GRB Detected by HETE
  70. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  71. HETE Trigger #1760 (GRB 010920B?): a new optical source
  72. HETE Trigger #1759 (GRB 010920?) optical observations
  73. GRB001109, Host Galaxy Astrometry
  74. GRB000926, Host Galaxy Observations
  75. GRB001109, Host Galaxy Spectroscopic Observations
  76. Probable SGR or Short Duration GRB Detected by HETE
  77. GRB000926 Host Galaxy Observations
  78. GRB 010222: HST observations -- host galaxy and late-time decay
  79. BeppoSAX/GRBM detection of GRB 010801
  80. GCN and HETE status
  81. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  82. BeppoSAX/GRBM detection of GRB010728
  83. GRB 010222 - WHT BVRI images
  84. SGR1900+14 burst seen by HETE: BeppoSAX data
  85. GRB 010629 Optical Observations
  86. GRB010629: Optical Observations
  87. SGR1900+14: High Fluence Burst Localized by HETE
  88. GRB010629, optical observations
  89. IPN triangulation of GRB010629
  90. GRB010629: A Burst Localized by HETE
  91. SGR1900+14: Second Burst Localized by HETE
  92. SGR1900+14: A Burst Localized by HETE
  93. Possible burst from SGR1806-20
  94. IPN detection of SGR1900+14
  95. SGR1806-20: A Second, Intense Burst Localized by HETE
  96. GRB 00630: Host Galaxy
  97. SGR1806-20: Localization by HETE
  98. IPN triangulation of GRB010613
  99. IPN triangulation of GRB010612
  100. IPN triangulation of GRB010612

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