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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').
Advanced Search

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"

28857 results found.

  1. SGR1900+14 activity, November 2-4, 2002
  2. GRB021104: possible optical afterglow
  3. GRB 021016, optical observations
  4. GRB 021004: VRI observations at TNG: possible break
  5. GRB 021008, optical observations
  6. IPN triangulation of GRB021014 (large error box)
  7. GRB 021004: Additional V-band Polarimetric Observations
  8. GRB 021004: V-band Polarimetric Observations
  9. GRB 021004: Optical observations at RIKEN
  10. GRB 021004, SPM optical observations
  11. GRB021004: optical observations at Nyrola
  12. GRB021004: Optical Afterglow
  13. GRB 020903: Optical observations at RIKEN
  14. XRF 020903: Supernova
  15. IPN triangulation of GRB020914
  16. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  17. INTEGRAL GRBs added to GCN
  18. GRB020812: optical observation
  19. Second epoch K band imaging of GRB 020819
  20. K band observation of GRB 020819
  21. HETE 2275: Optical observations
  22. Polarimetry of GRB020813: evidence for variability
  23. GRB020812: optical observations
  24. GRB020813: Early Time Magnitude
  25. GRB020813, optical observations
  26. Early Time Limits for GRB020813
  27. GRB 020813 Afterglow Observations; Possible break
  28. GRB 020813 multiband optical observations
  29. GRB020813: optical afterglow
  30. GRB020813: Fading of Candidate OT
  31. GRB020813: Candidate Optical Afterglow
  32. GRB 020812 optical observation
  33. GRB020801, optical afterglow candidate
  34. GRB020625 (=H2081): A Long Burst Localized by HETE
  35. HETE #2081: Optical observations
  36. GRB 020531, simultaneous optical observations
  37. GRB020321 : Optical observations.
  38. GRB 020410, optical observations
  39. GRB 020331: Candidate Optical Afterglow
  40. GRB 020322: BeppoSAX observations of the X-ray afterglow
  41. SN 2002ap - peak brightness date (SN/GRB?)
  42. GRB020321: a faint BeppoSAX detection
  43. GRB020317, optical observations
  44. GRB020305, optical observations
  45. GRB020124, optical observations
  46. HETE 1896: Optical observations
  47. GRB011130 (=XRF011130), Optical Observations
  48. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  49. GRB 011030: K-band observations
  50. The X-ray Flash 011030 ('GRB 011030')
  51. GRB 011019 optical observation
  52. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  53. GRB 010921: The afterglow of HETE #1761
  54. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  55. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  56. GRB010921 Optical Observations
  57. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  58. HETE Trigger #1760 (GRB 010920B?): a new optical source
  59. HETE Trigger #1759 (GRB 010920?) optical observations
  60. BeppoSAX/GRBM detection of GRB 010801
  61. GCN and HETE status
  62. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  63. GRB 010629 Optical Observations
  64. IPN triangulation of GRB010613
  65. IPN triangulation of GRB010612
  66. GRB010518: a faint BeppoSAX detection
  67. GRB010324: BeppoSAX/GRBM data
  68. GRB 010214: X-Ray afterglow
  69. GRB010213, optical observations
  70. GRB010126: CONCAM crude optical limits during GRB
  71. HETE positions added to GCN
  72. CONCAM null result on GRB001005
  73. CONCAM crude optical limits before and after GRB000926
  74. GRB000607, optical observations
  75. GRB 000615: NIR observations
  76. IPN triangulation of GRB000519
  77. RXTE/ASM and IPN localization of GRB 000508B
  78. BeppoSAX GRB000424
  79. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  80. GRB000408, lotis optical observations
  81. GRB 000313 - optical transient in the BATSE error box
  82. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  83. BATSE GRB trigger criterion changed
  84. GRB000210 X-ray afterglow
  85. GRB 000210: BATSE Observations
  86. GRB000201 Optical Observations
  87. GRB 000201: TAROT optical observations
  88. BATSE GRB trigger criteria changed
  89. BATSE+IPN location of GRB000131
  90. BATSE location of GRB000126
  91. BATSE Observations of GRB000115
  92. Second RXTE Observation of GRB 000115
  93. Single IPN error box for GRB991229
  94. GRB 991216: Updated BATSE parameters
  95. GRB 991216--Summary of RXTE Observations
  96. GRB 991216: Extremely bright BATSE burst
  97. GRB991106: BeppoSAX/BATSE results
  98. BeppoSAX NFI Observation of GRB991106
  99. GRB 991105: BATSE Observations
  100. GRB991106, optical observation at SAO-RAS

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