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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"

21392 results found.

  1. GRB060901: Candidate optical afterglow
  2. GRB070309: Swift/XRT possible afterglow detection
  3. GRB 070125: Chandra X-ray Confirmation of Jet Break
  4. GRB 070309: Swift/UVOT Upper Limits
  5. GRB 070306, optical observation
  6. Swift UVOT Finding Charts for GRB 070309
  7. GRB 070125: X-ray light curve analysis
  8. VLA observation of GRB 070306
  9. GRB 070306: NOT observations
  10. GRB 070306 Swift/UVOT refined analysis
  11. GRB 070306: ART-3 early optical and near infrared constraints
  12. GRB 070306, Swift-BAT refined analysis
  13. GRB 070306: XRT Team Refined Analysis
  14. GRB 070306: Optical and IR observations with KANATA
  15. GRB070306 - SDSS Pre-burst Observations
  16. GRB 070306: Swift detection of a burst
  17. GRB 070223: NIR observations at WHT
  18. GRB070227: Swift-XRT refined analysis
  19. GRB 070125, deep late-time optical observation
  20. VLA observation of GRB 070224
  21. GRB 070227: optical observations
  22. GRB 070223: Optical Observations
  23. GRB 070227: optical observations
  24. GRB 070227: Swift/UVOT Upper Limits
  25. GRB 070227: TAROT La Silla observatory optical observations
  26. GRB 070227, Swift-BAT refined analysis
  27. GRB070227: possible X-ray afterglow detection
  28. GRB 070227: Swift detection of a burst in ground analysis
  29. GRB 070224: Optical afterglow confirmation
  30. GRB 070224: Swift/UVOT Upper Limits
  31. GRB070224: Swift-XRT Astrometrically Corrected Position
  32. VLA observation of GRB 070223
  33. VLA observation of GRB 070220
  34. GRB070224: Magellan Imaging Observations
  35. GRB 070224: WHT K-band imaging
  36. GRB070224: Gemini Imaging Observations
  37. GRB 070224: SARA upper limit
  38. GRB070224: Swift-XRT Refined Analysis
  39. GRB 070224: optical afterglow candidate
  40. GRB 070224, Swift-BAT refined analysis
  41. GRB 070224: MASTER-Net refind analysis
  42. GRB 070224: MASTER-VWF-Kislovodsk observations
  43. GRB 070224: Swift detection of a burst
  44. GRB070223: Swift/UVOT refined analysis
  45. GRB 070223, Swift-BAT refined analysis
  46. GRB070223: MASTER-VWF-Kislovodsk observations
  47. GRB 070223: Swift-XRT Refined Analysis
  48. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  49. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  50. GRB 070223: MDM Observations
  51. GRB070223: Swift burst
  52. Konus-Wind and Konus-A observations of GRB 070220
  53. GRB 070220 Swift-BAT Refined Analysis
  54. Swift/UVOT refined analysis of GRB070220
  55. GRB 070209: Swift XRT refined analysis
  56. GRB 070220: Swift-XRT Refined Analysis
  57. GRB 070219: Gemini Observations
  58. GRB 070220 : Faulkes Telescope North optical limit
  59. GRB 070220: Swift detection of a burst
  60. GRB070219: MASTER-VWF-Kislovodsk observations
  61. GRB 070219: XRT Refined Analysis
  62. GRB 070219: Swift/UVOT Upper limits
  63. GRB 070219: I-band observations
  64. GRB 070219, Swift-BAT refined analysis
  65. GRB 070219: optical TNG observations
  66. GRB 070219: Liverpool Telescope Observations
  67. GRB 070219: ROTSE-III Optical Limits
  68. GRB070219 - SDSS Pre-Burst Observations
  69. GRB 070219: Swift detection of a burst
  70. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  71. Swift-BAT trigger 260304 is NOT a burst or transient
  72. GRB 070209: Swift XRT analysis
  73. GRB 070208: MARGE Optical Observations
  74. IPN localization of very bright long hard GRB 070207
  75. IPN localization of very intense short GRB 070201
  76. GRB 070209, Swift-BAT refined analysis of the short hard burst
  77. GRB 070209: Swift detection of a short hard burst
  78. GRB 070208: Swift XRT refined analysis
  79. GRB 070208: RAPTOR detection of early afterglow onset
  80. GRB 070208: MDM Optical Decay
  81. GRB 070208, Swift-BAT refined analysis
  82. GRB 070208: Early IR detection and afterglow astrometry
  83. GRB070208: Faulkes Telescope North Afterglow Identification
  84. GRB 070208: ROTSE-III Optical Limits
  85. GRB 070208: MDM Observations
  86. GRB 070208: Swift detection of a burst
  87. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  88. GRB 070129: afterglow confirmation
  89. GRB070124: Swift-XRT Follow-up Observation
  90. GRB070126: Swift-XRT Observation
  91. GRB 070129: Swift/UVOT Upper limits
  92. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  93. GRB061217: MAGIC telescope GeV observation
  94. GRB 070129, Swift-BAT refined analysis of a particularly long
  95. GRB 070129: Xinglong TNT optical Upper Limit
  96. GRB 070129: Swift-XRT Refined Analysis
  97. GRB 070129: VLT observations
  98. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  99. GRB 070129: Swift detection of a burst
  100. GRB 070126: Swift/UVOT refined analysis

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