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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

22854 results found.

  1. GRB 070412: Swift detection of a burst
  2. GRB 070411: IAC80 optical observations
  3. GRB 070411 : Liverpool Telescope Observations
  4. GRB 070411: Swift detection of a burst with optical afterglow
  5. GRB 070406: Swift XRT team further analysis
  6. Suzaku ToO observation of SGR 1806-20
  7. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  8. GRB 070406: Correction to the optical candidate in GCN6253
  9. GRB 070406: Gemini South Imaging and XRT analysis
  10. GRB070406: Swift UVOT observations
  11. Short GRB 070406 - Possible Bright Host Galaxy
  12. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  13. GRB 070406: NOT observations
  14. GRB 070406: SARA upper limit
  15. GRB 070406: Xinglong TNT optical Upper Limit
  16. GRB 070406: Swift detection of a burst
  17. GRB 070402: Suzaku WAM observation of the prompt emission
  18. Konus-Wind and Konus-A observations of GRB 070402
  19. IPN triangulation of GRB070402
  20. GRB 070328: Suzaku WAM observation of the prompt emission
  21. UVOT observations of GRB070330
  22. GRB 070330: TAROT La Silla observatory optical observations
  23. GRB 070330: Swift-XRT refined analysis
  24. GRB 070330 - Watcher Observations
  25. GRB 070330: Swift detection of a burst
  26. GRB 070328: Swift/UVOT Upper Limits
  27. long burst from SGR 1806-20 detected on March 26
  28. GRB 070328 : Suzaku ToO follow up starts
  29. GRB 070328: Swift detection of a burst
  30. GRB 070311, deep optical photometry
  31. Short-Hard GRB 070209: PROMPT Observations
  32. GRB 070318: absorption-line redshift
  33. GRB070318: Swift UVOT continuing observations
  34. GRB070318: Swift-XRT refined analysis
  35. GRB 070318, Swift-BAT refined analysis
  36. GRB 070318: Swift detection of a burst with an optical afterglow
  37. VLA observation of GRB 070311
  38. GRB 070311: Optical observation.
  39. GRB 070306: possible emission-line redshift
  40. GRB 070311: SARA upper limit
  41. GRB 070311: RAPTOR Detection of Optical Emission
  42. GRB070311: FRAM early follow-up limit
  43. GRB 070311: P60 Observations
  44. GRB 070311: Swift/UVOT Upper Limits
  45. GRB 070311: MITSuME Okayama Optical Observation
  46. GRB 070311: Swift-XRT refined analysis
  47. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  48. GRB 070311: REM candidate afterglow
  49. GRB060901: Candidate optical afterglow
  50. GRB070309: Swift/XRT possible afterglow detection
  51. GRB 070125: Chandra X-ray Confirmation of Jet Break
  52. GRB 070309: Swift/UVOT Upper Limits
  53. GRB 070306, optical observation
  54. Swift UVOT Finding Charts for GRB 070309
  55. VLA observation of GRB 070306
  56. GRB 070306: NOT observations
  57. GRB 070306 Swift/UVOT refined analysis
  58. GRB 070306: ART-3 early optical and near infrared constraints
  59. GRB 070306: IR observations and candidate afterglow
  60. GRB 070306: Optical and IR observations with KANATA
  61. GRB070306 - SDSS Pre-burst Observations
  62. GRB 070306: Swift detection of a burst
  63. GRB 060605 new redshift
  64. GRB 070125, deep late-time optical observation
  65. VLA observation of GRB 070224
  66. GRB 070227: Swift/UVOT Upper Limits
  67. GRB 070227: TAROT La Silla observatory optical observations
  68. GRB 070227, Swift-BAT refined analysis
  69. GRB 070227: Swift detection of a burst in ground analysis
  70. GRB 920925C: optical afterglow candidate
  71. GRB 070224: Swift/UVOT Upper Limits
  72. VLA observation of GRB 070223
  73. VLA observation of GRB 070220
  74. GRB070224: Magellan Imaging Observations
  75. GRB 070224: WHT K-band imaging
  76. GRB 070224: MDM Observations
  77. GRB070224: Gemini Imaging Observations
  78. GRB 070224: SARA upper limit
  79. GRB070224: Swift-XRT Refined Analysis
  80. GRB 070224: optical afterglow candidate
  81. GRB 070224: MASTER-Net refind analysis
  82. GRB 070224: MASTER-VWF-Kislovodsk observations
  83. GRB 070224: Swift detection of a burst
  84. GRB 070223: Optical observations
  85. GRB070223: Swift/UVOT refined analysis
  86. GRB 070223: Optical-IR observation with KANATA
  87. GRB070223: MASTER-VWF-Kislovodsk observations
  88. GRB070223 - SDSS Pre-Burst Observations
  89. GRB070223: Swift burst
  90. GRB 070220: MITSuME Okayama Optical Observation
  91. GRB 070220: ART-3 Optical and NIR limits
  92. Swift/UVOT refined analysis of GRB070220
  93. GRB 070209: Swift XRT refined analysis
  94. GRB 070220: Observation with the KANATA 1.5m telescope
  95. GRB 070219: Gemini Observations
  96. GRB 070220: Swift detection of a burst
  97. GRB070219: MASTER-VWF-Kislovodsk observations
  98. GRB 070219: Swift/UVOT Upper limits
  99. GRB 070219: I-band observations
  100. GRB 070219: optical TNG observations

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