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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
  1. GRB 120909A: X-Shooter redshift 3.93
  2. GRB 120909A: GROND detection of the afterglow
  3. Skynet/PROMPT Observations of GRB120909A
  4. GRB 120909A: Swift detection of a burst
  5. GRB 120907A: EVLA observations
  6. GRB 120907A: Swift/UVOT Detection
  7. GRB 120907A: Swift-XRT refined Analysis
  8. GRB 120907A: Spectroscopy from OSIRIS/GTC
  9. GRB 120907A: Enhanced Swift-XRT position
  10. GRB 120907A: Fermi GBM detection
  11. GRB 120907A: Swift-BAT refined analysis
  12. GRB 120907A: NOT optical observations
  13. GRB 120907A MASTER optical observations
  14. GRB 120907A: ROTSE-III Optical Limits
  15. GRB 120907A: Swift detection of a burst with optical counterpart
  16. XMM observations of the short GRB120804A
  17. GRB 120819A: optical upper limit
  18. GRB 120802A: optical observations in CrAO
  19. GRB 120830A: Further Swift Observations
  20. GRB 120830A: catalog source at Uvot position
  21. GRB 120830A: Swift-XRT and UVOT observations
  22. GRB 120830A: Fermi GBM observation
  23. Konus-Wind observation of GRB 120830A
  24. GRB 120830A: early MASTER optical limit
  25. IPN Triangulation of short GRB 120830A
  26. GRB 120830A: Fermi-LAT detection of a short burst
  27. Fermi trigger 368003226 : MASTER optical observations
  28. GRB 120819A: Swift/UVOT Upper Limits
  29. GRB 120817A: Swift/UVOT Upper Limits
  30. GRB 120817B: Deep limit on the optical afterglow from du Pont and Magellan observations
  31. GRB 120821A: Swift/XRT observations
  32. GRB 120821A: Swift/UVOT Upper Limits
  33. GRB 120821A: GROND upper limits
  34. GRB 120821A: a long GRB detected by INTEGRAL
  35. GRB 120817B - PTF Observations
  36. GRB 120817A: RAPTOR Limits During Gamma-Ray Emitting Interval
  37. GRB 120811C: optical observations
  38. GRB 120817B: BAT location in ground analysis and refined analysis
  39. GRB 120819A: MASTER final limits
  40. GRB 120819A: Bassano Bresciano Observatory optical observations
  41. GRB 120819A: Swift-BAT refined analysis
  42. GRB 120819A: GROND afterglow confirmation
  43. GRB 120819A: Swift-XRT refined Analysis
  44. GRB 120819A: MITSuME Ishigakijima upper limits
  45. GRB 120819A: MITSuME Okayama Optical upper limits
  46. GRB 120819A: Enhanced Swift-XRT position
  47. GRB 120819A: afterglow candidate from NOT
  48. GRB 120819A: MASTER optical observations
  49. GRB 120819A: Swift detection of a burst
  50. GRB 120817B: Swift-XRT observations
  51. GRB 120811C: optical observations
  52. GRB 120816A: Swift/UVOT Detection of the Optical Afterglow
  53. GRB 120815A: MASTER-ICATE observations
  54. Konus-Wind observation of GRB 120816B
  55. IPN Triangulation of GRB 120816B (short/exceptionally intense)
  56. Konus-Wind observation of GRB 120817B
  57. GRB 120817A: Swift-XRT refined Analysis
  58. GRB 120817B: LCO Optical Observations
  59. GRB 120817B: Fermi GBM detection
  60. IPN Triangulation of GRB 120817B (short/very intense)
  61. GRB 120817A: Swift-BAT refined analysis
  62. GRB 120816A: optical upper limit
  63. GRB 120817A: Enhanced Swift-XRT position
  64. GRB 120815A: Swift/UVOT Detection of the Optical Afterglow
  65. GRB 120816A: Bassano Bresciano Observatory optical observations
  66. GRB 120817A: FTN and FTS observations
  67. GRB 120816A: Swift-XRT refined Analysis
  68. GRB 120817A: Swift-XRT observations
  69. GRB 120817A: Swift detection of a burst
  70. GRB 120816A: Enhanced Swift-XRT position
  71. GRB 120816A: Swift-BAT refined analysis
  72. GRB 120816A: BOOTES-2 observations
  73. GRB120816A: OPTIMA discovery of optical counterpart
  74. GRB 120816A: TAROT Calern observatory optical observations
  75. GRB 120816A: ROTSE-III Optical Limits
  76. GRB 120816A: Swift detection of a burst
  77. GRB 120815A: Swift-XRT refined Analysis
  78. GRB 120815A: Swift-BAT refined analysis
  79. GRB 120805A: Liverpool Telescope optical candidate detection
  80. GRB 120815A: Enhanced Swift-XRT position
  81. GRB 120815A: VLT/X-shooter redshift
  82. GRB 120815A: GROND afterglow candidate
  83. GRB 120815A: Swift-XRT observations
  84. GRB 120815A: TAROT La Silla observatory optical observations
  85. GRB 120815A: Swift detection of a burst
  86. GRB 120811B: Fermi GBM observation
  87. GRB 120804A: Possible temporal break in the X-ray light-curve
  88. GCN for GRB 120811C
  89. GRB 120811A: Swift/XRT-UVOT Obseravations
  90. GRB120804A: Chandra observations and afterglow detection
  91. GRB 120805A: optical afterglow confirmation from the NOT
  92. GRB 120805A: Enhanced Swift-XRT position
  93. GRB 120811C: EVLA Observations
  94. GRB 120811C: RTT150 optical observations
  95. GRB 120811C: MASTER-Tunka OT observations
  96. GRB 120811C: Swift-BAT refined analysis
  97. GRB 120811A: Swift-BAT refined analysis
  98. GRB 120811C: NOT redshift
  99. GRB 120811C: Bassano Bresciano Observatory optical observations
  100. GRB 120811C: Swift-XRT refined Analysis

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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