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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"

3029 results found.

  1. GRB080307: Optical upper limits
  2. GRB 080218B: Swift detection of a burst
  3. GRB080212: Optical afterglow candidate observed by MITSuME Telescope
  4. GRB 080205: Swift/UVOT observations
  5. GRB 080205: Enhanced Swift-XRT position
  6. GRB 080205: KAIT OA detection
  7. GRB 080205: Swift detection of a burst
  8. GRB 080129: GROND detection in all bands, and fading
  9. GRB 080129: GROND detection of the optical/NIR afterglow, and fading
  10. IPN triangulation of GRB080122
  11. GRB 080121: Nearby SDSS galaxies
  12. GRB 080120: Swift-XRT refined analysis
  13. GRB080120: Swift XRT position
  14. GRB 071227: Swift detection of a burst
  15. GRB071020: optical observations
  16. GRB 071122 Swift-XRT refined analysis
  17. GRB 071122: Corrected P60 Coordinates
  18. GRB 071122: P60 Optical Afterglow Candidate
  19. GRB 071122: Swift detection of a burst
  20. GRB 071118, Swift-BAT refined analysis
  21. VLT FORS2 observations of short hard GRB071112B
  22. ATCA radio observations of short hard burst GRB 071112B
  23. GRB 071112C: SARA upper limit
  24. GRB 071112C: ROTSE-III Confirmation of Optical Counterpart
  25. GRB 071028B Swift-BAT detection of a burst
  26. GRB 071025: Kuiper Telescope Optical Observations
  27. GRB 071025, Swift-BAT refined analysis
  28. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  29. GRB 071013: TNT optical data refined analysis
  30. GRB 071010B: Photometry after 1.6 days
  31. GRB 071010A: Continued Keck Imaging
  32. GRB 071006, Swift-BAT refined analysis
  33. GRB 071010B: Swift detection of a burst
  34. Recent SGR1806-20 Activity
  35. GRB 070917: Swift detection of a bright burst
  36. GRB 070808, Swift-BAT refined analysis
  37. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  38. GRB 070729, Swift-BAT refined analysis
  39. GRB 070724B: Swift-XRT afterglow likely candidate
  40. GRB 070721A : Faulkes Telescope South optical limit
  41. GRB 070721A, Swift-BAT refined analysis
  42. GRB 070621: Watcher Observations
  43. GRB070520B: optical observations
  44. GRB 070521, optical observation
  45. GRB 070521, Swift-BAT refined analysis
  46. GRB 070521: optical limit by Pi of the Sky
  47. GRB 070419A: RAPTOR Detection of Early Emission
  48. GRB070330: Correction to UVOT position
  49. UVOT observations of GRB070330
  50. GRB 070330, Swift-BAT refined analysis
  51. GRB 070330: Swift-XRT refined analysis
  52. GRB 070330: Swift detection of a burst
  53. GRB 070311: MDM Optical Detection
  54. GRB070227: Swift-XRT refined analysis
  55. VLA observation of GRB 070224
  56. GRB 070227: optical observations
  57. GRB 070227: optical observations
  58. GRB 070209: Swift XRT analysis
  59. GRB 070103: Swift detection of a burst
  60. Retractions of previous Swift-BAT triggers
  61. GRB 061201: Magellan Redshift of nearby Abell cluster
  62. GRB061202 optical limit by "Pi of the Sky"
  63. RHESSI Spectrum of GRB061126
  64. GRB 061126: SARA Observations
  65. GRB 061126: Swift detection of a burst
  66. GRB061122: Swift/UVOT Optical Observations
  67. GRB 061110: Swift detection of a burst
  68. GRB061019: second epoch CrAO observations
  69. GRB 061028: MDM Observations
  70. GRB 061028, Swift-BAT refined analysis
  71. GRB061019: optical observations
  72. GRB 061007: Second Epoch ATCA Radio Observations
  73. GRB 061007: ATCA Radio Observations
  74. GRB060912: Swift/UVOT Observations
  75. GRB060904b optical detections (delayed report due to internet outage)
  76. GRB 060904B: RTT150 optical observations
  77. Two bright bursts from SGR 1806-20 detected with IBAS
  78. GRB 060825: VLA observations
  79. GRB 060825: XRT Team Refined Analysis
  80. GRB 060825: Swift-BAT Refined Analysis
  81. GRB060825: BOOTES-IR optical observations
  82. Konus-Wind observation of GRB 060813
  83. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  84. GRB 060805: Swift detection of a burst
  85. GRB 060801, optical observation
  86. GRB 060605: SkyNet Optical Limits
  87. GRB 060712: Swift detection of a burst
  88. GRB 060502B: A Bright Early-type Galaxy as Putative Host of the Short Burst
  89. GRB 060607: REM NIR afterglow
  90. GRB 060522: Swift detection of a burst with possible optical afterglow
  91. GRB 060516: Swift detection of a burst
  92. GRB060501: P60 imaging and afterglow candidate
  93. GRB060428B, optical observation
  94. GRB060424: optical afterglow detection
  95. GRB 060424: Refined analysis of the Swift-BAT burst
  96. GRB 060403: Swift detection of a burst
  97. GRB 060312: ROTSE-III Optical Limits
  98. Bright short hard GRB 060303: IPN localization and Konus spectrum
  99. GRB 060223B: Swift XRT possible afterglow
  100. GRB 060218/SN 2006aj: RBO optical observations

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