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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"

27397 results found.

  1. GRB 070412 Liverpool Telescope optical limit
  2. GRB 070412: Optical observations at Crni Vrh
  3. GRB 070412: further NOT observations
  4. GRB 070412: Gemini/GMOS afterglow candidate
  5. GRB 070412: IAC80 optical afterglow candidate
  6. GRB 070412: NOT observations
  7. GRB 070411, Swift-BAT refined analysis
  8. GRB 070412: Swift detection of a burst
  9. GRB 070411: IAC80 optical observations
  10. GRB 070411 : Liverpool Telescope Observations
  11. GRB 070411: Swift detection of a burst with optical afterglow
  12. GRB 070406: Swift XRT team further analysis
  13. Suzaku ToO observation of SGR 1806-20
  14. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  15. GRB 070406, Swift-BAT refined analysis
  16. GRB 070406: Correction to the optical candidate in GCN6253
  17. GRB 070406: Gemini South Imaging and XRT analysis
  18. GRB070406: Swift UVOT observations
  19. GRB 070406: further analysis of NOT images.
  20. Short GRB 070406 - Possible Bright Host Galaxy
  21. GRB 070406: NOT observations
  22. GRB 070406: Optical candidate
  23. GRB 070406: SARA upper limit
  24. GRB 070406: Xinglong TNT optical Upper Limit
  25. GRB 070402: Suzaku WAM observation of the prompt emission
  26. GRB 070328: Suzaku WAM observation of the prompt emission
  27. UVOT observations of GRB070330
  28. GRB 070330, Swift-BAT refined analysis
  29. GRB 070330: TAROT La Silla observatory optical observations
  30. GRB 070330 - Watcher Observations
  31. GRB 070330: Swift detection of a burst
  32. GRB 070328: Swift/UVOT Upper Limits
  33. long burst from SGR 1806-20 detected on March 26
  34. GRB 070328: Swift/XRT Refined Analysis
  35. GRB 070328 : Suzaku ToO follow up starts
  36. GRB 070328, Swift-BAT refined analysis
  37. GRB 070328: Swift detection of a burst
  38. GRB 070311, deep optical photometry
  39. Short-Hard GRB 070209: PROMPT Observations
  40. GRB 070318: absorption-line redshift
  41. GRB070318: Swift UVOT continuing observations
  42. GRB 070318, Swift-BAT refined analysis
  43. GRB 070318: Swift detection of a burst with an optical afterglow
  44. GRB 070311: Late Central Engine Activity Optical Flare??
  45. VLA observation of GRB 070311
  46. GRB 070311: Optical observation.
  47. GRB 070306: possible emission-line redshift
  48. GRB 070311: SARA upper limit
  49. GRB 070309: variability of the XRT afterglow candidate
  50. GRB070311: FRAM early follow-up limit
  51. GRB 070311: P60 Observations
  52. GRB 070311: Swift/UVOT Upper Limits
  53. GRB 070311: MITSuME Okayama Optical Observation
  54. GRB 070311: Swift-XRT refined analysis
  55. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  56. GRB 070311: REM candidate afterglow
  57. GRB 070311: a long GRB detected by INTEGRAL
  58. GRB060901: Candidate optical afterglow
  59. GRB 070125: Chandra X-ray Confirmation of Jet Break
  60. GRB 070309: Swift/UVOT Upper Limits
  61. GRB 070306, optical observation
  62. Swift UVOT Finding Charts for GRB 070309
  63. GRB 070309: A long GRB detected by INTEGRAL
  64. GRB 070125: X-ray light curve analysis
  65. VLA observation of GRB 070306
  66. GRB 070306: NOT observations
  67. GRB 070306 Swift/UVOT refined analysis
  68. GRB 070306: IR observations and candidate afterglow
  69. GRB 070306, Swift-BAT refined analysis
  70. GRB 070306: XRT Team Refined Analysis
  71. GRB 070306: Optical and IR observations with KANATA
  72. GRB070306 - SDSS Pre-burst Observations
  73. GRB 070306: Swift detection of a burst
  74. GRB070227: Swift-XRT refined analysis
  75. GRB 060605 new redshift
  76. GRB 070125, deep late-time optical observation
  77. VLA observation of GRB 070224
  78. GRB 070227: Swift/UVOT Upper Limits
  79. GRB 070227: TAROT La Silla observatory optical observations
  80. GRB 070227, Swift-BAT refined analysis
  81. GRB 070227: Swift detection of a burst in ground analysis
  82. GRB 070224: Swift/UVOT Upper Limits
  83. VLA observation of GRB 070223
  84. VLA observation of GRB 070220
  85. GRB070224: Magellan Imaging Observations
  86. GRB 070224: WHT K-band imaging
  87. GRB 070224: MDM Observations
  88. GRB070224: Gemini Imaging Observations
  89. GRB 070224: SARA upper limit
  90. GRB070224: Swift-XRT Refined Analysis
  91. GRB 070224: optical afterglow candidate
  92. GRB 070224, Swift-BAT refined analysis
  93. GRB 070224: MASTER-Net refind analysis
  94. GRB 070224: MASTER-VWF-Kislovodsk observations
  95. GRB 070224: Swift detection of a burst
  96. GRB 070223: Optical observations
  97. GRB070223: Swift/UVOT refined analysis
  98. GRB 070223: Optical-IR observation with KANATA
  99. GRB 070223, Swift-BAT refined analysis
  100. GRB070223: MASTER-VWF-Kislovodsk observations

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