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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"

27803 results found.

  1. GRB 070419 optical afterglow candidate
  2. GRB 070419A: ROTSE-III Optical Limits
  3. GRB 070419: Swift detection of a burst
  4. Swift-BAT Trigger 276045 is a Cosmic Ray Shower event
  5. Trigger 276045: Swift detection of a possible burst
  6. GRB 070406: Swift XRT refined analysis
  7. GRB 070411: TLS data shows plateau, flares
  8. GRB070412: Swift UVOT observations
  9. GRB 070411: Swift/UVOT observations
  10. GRB 070412, Swift-BAT refined analysis
  11. GRB 070412: Swift-XRT refined analysis
  12. GRB 070411: Swift-XRT refined analysis
  13. GRB 070412: Optical observations at Crni Vrh
  14. GRB 070412: Swift-XRT refined position
  15. GRB 070412: further NOT observations
  16. GRB 070412: Gemini/GMOS afterglow candidate
  17. GRB 070412: NOT observations
  18. GRB 070411, Swift-BAT refined analysis
  19. GRB 070412: Swift detection of a burst
  20. GRB 070411: ROTSE-III Detection of Optical Counterpart
  21. GRB 070411: Tautenburg RRM Afterglow Confirmation
  22. GRB 070411: Swift detection of a burst with optical afterglow
  23. GRB 070406: Swift XRT team further analysis
  24. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  25. GRB 070406, Swift-BAT refined analysis
  26. GRB070406: Swift UVOT observations
  27. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  28. GRB 070406: SARA upper limit
  29. GRB 070406: Xinglong TNT optical Upper Limit
  30. GRB 070406: Swift detection of a burst
  31. INTEGRAL ToO Observation of SGR1806-20
  32. UVOT observations of GRB070330
  33. GRB 070330, Swift-BAT refined analysis
  34. GRB 070330: TAROT La Silla observatory optical observations
  35. GRB 070330: Swift-XRT refined analysis
  36. GRB 070330: Swift detection of a burst
  37. GRB 070328: pseudo-z~2.75 from spectral parameters of the prompt
  38. Konus-Wind observation of GRB 070328
  39. GRB 070328: Swift/UVOT Upper Limits
  40. GRB 070328: Swift/XRT Refined Analysis
  41. GRB 070328, Swift-BAT refined analysis
  42. GRB 070328: Swift detection of a burst
  43. GRB070318: Swift UVOT indicates unusual optical/UV afterglow
  44. GRB 070318: Gemini + Magellan spectra
  45. GRB070318: Swift UVOT continuing observations
  46. GRB070318: Swift-XRT refined analysis
  47. GRB 070318: Swift/UVOT Continued Observations
  48. GRB 070318, Swift-BAT refined analysis
  49. GRB 070318: Swift detection of a burst with an optical afterglow
  50. GRB 070311: Late Central Engine Activity Optical Flare??
  51. VLA observation of GRB 070311
  52. GRB 070311: Tautenburg sees afterglow fading
  53. GRB 070309: variability of the XRT afterglow candidate
  54. GRB 070311: RAPTOR Detection of Optical Emission
  55. GRB 070311: MDM Optical Detection
  56. GRB 070311: Swift/UVOT Upper Limits
  57. GRB 070311: Swift-XRT refined analysis
  58. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  59. GRB070309: Swift/XRT possible afterglow detection
  60. GRB 070125: Chandra X-ray Confirmation of Jet Break
  61. GRB 070309: Swift/UVOT Upper Limits
  62. Swift UVOT Finding Charts for GRB 070309
  63. GRB 070125: X-ray light curve analysis
  64. VLA observation of GRB 070306
  65. GRB 070306: NOT observations
  66. GRB 070306 Swift/UVOT refined analysis
  67. GRB 070306, Swift-BAT refined analysis
  68. GRB 070306: XRT Team Refined Analysis
  69. GRB070306 - SDSS Pre-burst Observations
  70. GRB 070306: Swift detection of a burst
  71. GRB070227: Swift-XRT refined analysis
  72. GRB 070125, deep late-time optical observation
  73. VLA observation of GRB 070224
  74. GRB 070227: optical observations
  75. GRB 070223: Optical Observations
  76. GRB 070227: optical observations
  77. GRB 070227: Swift/UVOT Upper Limits
  78. GRB 070227: TAROT La Silla observatory optical observations
  79. GRB 070227, Swift-BAT refined analysis
  80. GRB070227: possible X-ray afterglow detection
  81. GRB 070227: Swift detection of a burst in ground analysis
  82. GRB 920925C: optical afterglow candidate
  83. GRB 070224: Optical afterglow confirmation
  84. GRB 070224: Swift/UVOT Upper Limits
  85. GRB070224: Swift-XRT Astrometrically Corrected Position
  86. VLA observation of GRB 070223
  87. VLA observation of GRB 070220
  88. GRB070224: Magellan Imaging Observations
  89. GRB070224: Gemini Imaging Observations
  90. GRB 070224: SARA upper limit
  91. GRB070224: Swift-XRT Refined Analysis
  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, Swift-BAT refined analysis
  99. GRB070223: MASTER-VWF-Kislovodsk observations
  100. GRB 070223: Swift-XRT Refined Analysis

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