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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 111123A: Enhanced Swift-XRT position
  2. GRB 111123A: GMG optical observation
  3. GRB 111117A: Refined Chandra Astrometry
  4. GRB 111123A: Swift detection of a burst
  5. GRB 111117A, the review of the sky area in plate archives
  6. Konus-Wind observation of GRB 111121A
  7. GRB 111121A: Swift/UVOT Upper Limits
  8. GRB 111121A: Magellan/Megacam observations
  9. GRB 111121A: Swift-XRT refined Analysis
  10. GRB 111121A: Swift-BAT refined analysis
  11. GRB 111117A: Chandra detection of the afterglow
  12. GRB 111121A: Enhanced Swift-XRT position
  13. GRB 111121A: Swift detection of a short hard burst
  14. GRB 111117A: Gemini Afterglow Limits
  15. GRB 111117A: optical upper limit in CrAO
  16. GRB 111117A: Fermi GBM observation
  17. GRB 111117A: further NOT observations
  18. GRB 111117A: EVLA observations
  19. GRB 111117A: TNG observations
  20. GRB 111117A: Swift/UVOT Upper Limits
  21. GRB 111117A: GROND observations
  22. GRB 111117A: Gemini host observation
  23. GRB111117A: Magellan IMACS observations
  24. GRB 111117A: Swift-XRT refined Analysis
  25. GRB111107A: Further ATCA observations - no detection
  26. GRB 111117A: NOT observations
  27. GRB 111117A: Chandra ToO observation scheduled
  28. GRB 111117A: Swift-BAT refined analysis of a short hard burst
  29. GRB 111117A: GMG upper limit
  30. GRB 111117A: Swift detection of a short hard burst
  31. GRB111107A: ATCA observations - upper limit and a possible detection
  32. Konus-Wind observation of GRB 111113A
  33. IPN Triangulation of GRB 111113A (short/hard/intense)
  34. XRF 111111A/MAXI J0158-744: MAXI GSC refined analysis
  35. XRF 111111A/MAXI J0158-744: MAXI GSC and SSC detection of a soft X-ray transient near SMC
  36. GRB 111109A: Swift-XRT refined Analysis
  37. GRB 111109A: Swift/UVOT Photometry
  38. GRB 111109A: Swift-BAT refined analysis
  39. GRB 111109A: Enhanced Swift-XRT position
  40. GRB 111109A: Swift-XRT observations
  41. GRB 111109A: Swift detection of a burst
  42. GRB 111103B: optical upper limit of CrAO
  43. GRB 111103B: optical upper limit of Mt. Terskol observatory
  44. GRB 111107A: Fermi GBM observation
  45. Continued Skynet observations of GRB111107A
  46. GRB 111107A: Swift-XRT refined Analysis
  47. GRB 111107A: VLT/X-shooter spectroscopy
  48. GRB 111107A: APEX submm observation
  49. GRB 111107A: Swift/UVOT Afterglow Analysis
  50. GRB 111107A: Swift-BAT refined analysis
  51. GRB 111107A: Enhanced Swift-XRT position
  52. GRB 111107A: Gemini-South Redshift
  53. GRB 111107A: GROND observations
  54. Skynet observations of GRB 111107A
  55. GRB 111107A: Swift detection of a burst with an optical counterpart
  56. GRB 111103B: MITSuME Akeno Optical upper limits
  57. Konus-Wind observation of GRB 111103B
  58. GRB 111103B : WIYN 3.5m NIR observations
  59. GRB 111103B: Swift-XRT refined Analysis
  60. GRB 111103A: Fermi GBM observation
  61. GRB111103B Swift/UVOT Upper Limits
  62. GRB 111103B: optical observations from TAU, Ka-Dar
  63. Trigger 506913: MASTER detection of Swift J1922.7-1716 optical counterpart
  64. GRB 111103B: Enhanced Swift-XRT position
  65. GRB 111103B: Swift-BAT refined analysis
  66. GRB 111103A: Swift-BAT refined analysis
  67. Trigger 506913: Swift detection of Swift J1922.7-1716 and its optical counterpart
  68. GRB 111022B: MASTER OT observations
  69. GRB 111103B: optical observations
  70. GRB 111103B: Swift detection of a strong burst from a GRB or Galactic source
  71. GRB 111103A: Swift detection of a burst
  72. Swift-BAT trigger 506884 is not a GRB
  73. GRB 111029A: RAPTOR Limits During the Gamma-ray Emitting Interval
  74. GRB 111029A: SAO RAS optical limits
  75. GRB 111029A: Super-LOTIS early limits
  76. All GCN Circulars available in a tarfile for data mining
  77. GRB 111026A: spectral lag value inconclusive for a short burst
  78. GRB111029A: MITSuME Ishigakijima Optical Upper Limits
  79. GRB 111029A: TNT optical upper limit, Correction to GCN 12503
  80. GRB 111029A: Swift-XRT refined Analysis
  81. GRB 111029A: PAIRITEL NIR Upper Limits
  82. GRB 111026A: Swift-BAT refined analysis
  83. GRB 111029A: Swift/UVOT Upper Limits
  84. GRB 111029A: KAIT optical limits
  85. GRB 111029A: Swift-BAT refined analysis
  86. GRB 111029A: TNT optical upper limit
  87. GRB 111029A: Enhanced Swift-XRT position
  88. GRB 111029A: Faulkes Telescope North observations
  89. GRB 111029A: optical upper limit
  90. GRB 111029A: ROTSE-III Optical Limits
  91. GRB 111029A: Swift detection of a burst
  92. GRB 111026A: Swift detection of a burst
  93. GRB 111022B: EVLA observations - correction to GCN 12495
  94. GRB 111022B: EVLA observations
  95. GRB 111022B: 10.4m GTC z'-band observations
  96. GRB111022B: D50 optical limit
  97. GRB 111020A: Chandra Observation
  98. GRB 111022B: BTA Optical Observations
  99. GRB 111022A: MITSuME Akeno Optical upper limits
  100. GRB 111024A: MAXI/GSC detection of a burst

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