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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"

19938 results found.

  1. Trigger 276045: Swift detection of a possible burst
  2. GRB 070406: Swift XRT refined analysis
  3. GRB 070411: TLS data shows plateau, flares
  4. GRB070412: Swift UVOT observations
  5. GRB 070411: Swift/UVOT observations
  6. GRB 070412, Swift-BAT refined analysis
  7. GRB 070412: Swift-XRT refined analysis
  8. GRB 070411: Swift-XRT refined analysis
  9. GRB 070412: Optical observations at Crni Vrh
  10. GRB 070412: Swift-XRT refined position
  11. GRB 070411, Swift-BAT refined analysis
  12. GRB 070412: Swift detection of a burst
  13. GRB 070411: ROTSE-III Detection of Optical Counterpart
  14. GRB 070411: Tautenburg RRM Afterglow Confirmation
  15. GRB 070411: Swift detection of a burst with optical afterglow
  16. GRB 070406: Swift XRT team further analysis
  17. Suzaku ToO observation of SGR 1806-20
  18. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  19. GRB 070406, Swift-BAT refined analysis
  20. GRB070406: Swift UVOT observations
  21. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  22. GRB 070406: SARA upper limit
  23. GRB 070406: Xinglong TNT optical Upper Limit
  24. GRB 070406: Swift detection of a burst
  25. INTEGRAL ToO Observation of SGR1806-20
  26. UVOT observations of GRB070330
  27. GRB 070330, Swift-BAT refined analysis
  28. GRB 070330: TAROT La Silla observatory optical observations
  29. GRB 070330: Swift-XRT refined analysis
  30. GRB 070330: Swift detection of a burst
  31. GRB 070328: pseudo-z~2.75 from spectral parameters of the prompt
  32. Konus-Wind observation of GRB 070328
  33. GRB 070328: Swift/UVOT Upper Limits
  34. long burst from SGR 1806-20 detected on March 26
  35. GRB 070328: Swift/XRT Refined Analysis
  36. GRB 070328, Swift-BAT refined analysis
  37. GRB 070328: Swift detection of a burst
  38. GRB070318: Swift UVOT indicates unusual optical/UV afterglow
  39. GRB 070318: Gemini + Magellan spectra
  40. GRB070318: Swift UVOT continuing observations
  41. GRB070318: Swift-XRT refined analysis
  42. GRB 070318: Swift/UVOT Continued Observations
  43. GRB 070318, Swift-BAT refined analysis
  44. GRB 070318: Swift detection of a burst with an optical afterglow
  45. GRB 070311: Late Central Engine Activity Optical Flare??
  46. VLA observation of GRB 070311
  47. GRB 070309: variability of the XRT afterglow candidate
  48. GRB 070311: Swift/UVOT Upper Limits
  49. GRB 070311: Swift-XRT refined analysis
  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. Swift UVOT Finding Charts for GRB 070309
  54. GRB 070125: X-ray light curve analysis
  55. VLA observation of GRB 070306
  56. GRB 070306: NOT observations
  57. GRB 070306 Swift/UVOT refined analysis
  58. GRB 070306, Swift-BAT refined analysis
  59. GRB 070306: XRT Team Refined Analysis
  60. GRB070306 - SDSS Pre-burst Observations
  61. GRB 070306: Swift detection of a burst
  62. GRB070227: Swift-XRT refined analysis
  63. GRB 070125, deep late-time optical observation
  64. VLA observation of GRB 070224
  65. GRB 070227: optical observations
  66. GRB 070223: Optical Observations
  67. GRB 070227: optical observations
  68. GRB 070227: Swift/UVOT Upper Limits
  69. GRB 070227: TAROT La Silla observatory optical observations
  70. GRB 070227, Swift-BAT refined analysis
  71. GRB070227: possible X-ray afterglow detection
  72. GRB 070227: Swift detection of a burst in ground analysis
  73. GRB 070224: Optical afterglow confirmation
  74. GRB 070224: Swift/UVOT Upper Limits
  75. GRB070224: Swift-XRT Astrometrically Corrected Position
  76. VLA observation of GRB 070223
  77. VLA observation of GRB 070220
  78. GRB070224: Magellan Imaging Observations
  79. GRB070224: Gemini Imaging Observations
  80. GRB 070224: SARA upper limit
  81. GRB070224: Swift-XRT Refined Analysis
  82. GRB 070224, Swift-BAT refined analysis
  83. GRB 070224: MASTER-Net refind analysis
  84. GRB 070224: MASTER-VWF-Kislovodsk observations
  85. GRB 070224: Swift detection of a burst
  86. GRB070223: Swift/UVOT refined analysis
  87. GRB 070223, Swift-BAT refined analysis
  88. GRB070223: MASTER-VWF-Kislovodsk observations
  89. GRB 070223: Swift-XRT Refined Analysis
  90. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  91. GRB 070223: MDM Observations
  92. GRB070223: Swift burst
  93. Konus-Wind and Konus-A observations of GRB 070220
  94. GRB 070220 Swift-BAT Refined Analysis
  95. Swift/UVOT refined analysis of GRB070220
  96. GRB 070209: Swift XRT refined analysis
  97. GRB 070220: Swift-XRT Refined Analysis
  98. GRB 070220: Swift detection of a burst
  99. GRB070219: MASTER-VWF-Kislovodsk observations
  100. GRB 070219: XRT Refined Analysis

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