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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"

19599 results found.

  1. GRB 100904A: Swift-BAT refined analysis
  2. GRB 100904A: Swift detection of a burst
  3. GRB 100902A: Swift-BAT refined analysis
  4. GRB 100901A: optical observation at Mt.Terskol
  5. GRB 100901A: multicolor photometry at Mt.Terskol
  6. IPN Triangulation of the very bright GRB 100829A
  7. GRB 100901A: Lightbuckets Optical Observations
  8. GRB 100902A: 1.5m OSN I-band Upper Limits
  9. Tentative redshift of GRB100902A from Swift-XRT data
  10. GRB 100902A: Swift XRT refined analysis
  11. GRB 100902A: Swift/UVOT Upper Limits
  12. GRB 100902A: optical observation at Mt.Terskol
  13. GRB 100901A: optical observation at Mt.Terskol
  14. GRB 100902A: Enhanced Swift-XRT position
  15. GRB 100901A: TLS Observations: Break?
  16. GRB 100902A: MASTER Prompt Optical Observations
  17. GRB 100901A: ISON-NM optical observations
  18. GRB 100902A: MASTER Optical Early Limit
  19. GRB 100902A: Swift detection of a burst
  20. GRB 100901A: 1.5m OSN BVRI-band observations.
  21. GRB 100901A: ROTSE-III Detection
  22. Swift/UVOT Observations of GRB100901A
  23. GRB 100901A: Swift-XRT Team refined analysis
  24. GRB 100901A: Swift-BAT refined analysis
  25. GRB 100901A: optical observation at Mt.Terskol
  26. GRB 100901A: Enhanced Swift-XRT position
  27. GRB 100901A: optical observation at Mt.Terskol
  28. GRB 100901A: MASTER power low decay
  29. GRB 100901A: MASTER: the OT brightenning
  30. GRB 100901A: confirmation of the afterglow
  31. GRB 100901A: MASTER Optical Early Limits
  32. GRB 100901A: Faulkes Telescope North afterglow candidate
  33. GRB 100901A: Swift detection of a burst with an optical afterglow
  34. GRB 100823A: optical upper limit
  35. GRB 100814A: Maidanak optical observations
  36. GRB 100823A: optical observations
  37. GRB 100823A: MAXI/GSC detection
  38. GRB 100725B: Mondy optical upper limit
  39. GRB 100725B: Maidanak optical upper limit
  40. GRB 100823A: Swift/UVOT Evidence for Fading Afterglow Emission
  41. GRB100807A: R band observations
  42. GRB100823A : MOA optical observation
  43. GRB 100823A: Swift XRT refined analysis
  44. GRB 100823: 1.5m OSN I-band observations
  45. GRB 100823A: Swift/UVOT Upper Limits
  46. GRB 100823A: Swift-BAT refined analysis
  47. GRB 100823A: Enhanced Swift-XRT position
  48. GRB 100823A: Swift detection of a burst
  49. GRB 100814A: Suzaku WAM observation of the prompt emission
  50. GRB 100814A: ISON-NM optical observations
  51. EVLA radio afterglow detection of GRB 100814A
  52. GRB 100814A: optical observations
  53. Konus-Wind observation of GRB 100816A
  54. GRB 100816A: Fermi GBM observation
  55. Konus-Wind observation of GRB 100814A
  56. GRB 100816A: Gemini-N spectroscopy
  57. GRB 100816A: Swift UVOT Observations
  58. GRB100816A Swift-XRT refined analysis
  59. GRB 100816A: Swift-BAT spectral lag results
  60. GRB 100816A: 1.23m CAHA optical observations
  61. GRB 100816A, Swift-BAT refined analysis
  62. GRB 100816A: Enhanced Swift-XRT position
  63. GRB100814A - interesting UVOT lightcurve.
  64. GRB 100816A: TAROT Calern observatory optical detection
  65. GRB100816A: TNG optical afterglow confirmation.
  66. GRB 100816A: ROTSE-III Optical Limits
  67. GRB 100816A: Swift detection of a possibly short burst with optical afterglow
  68. Swift-BAT trigger 431756 is not a burst
  69. Swift/UVOT observations of GRB100814A - title correction to GCN 11097
  70. GRB 100814A: Fermi GBM observation
  71. Swift/UVOT Observations of GRB100814A - a clearer table.
  72. GRB 100814A: Swift-XRT refined analysis
  73. Swift/UVOT observations of GRB100814A
  74. GRB 100814A, Swift-BAT refined analysis
  75. GRB 100814A: Enhanced Swift-XRT position
  76. GRB 100814A: GROND Detection of the Optical/NIR Afterglow
  77. GRB 100814A: IAC80 R-band observations
  78. GRB 100814A: Swift UVOT observations of the optical afterglow
  79. GRB 100814A: Swift detection of a burst with an optical afterglow
  80. GRB 100814A: ROTSE-III Detection of Optical Counterpart
  81. Swift-BAT trigger 431582 likely is IGR J17464-2811
  82. GRB 100805A: optical observation in CrAO (correction to the GCN 11077 and second epoch)
  83. GRB 100805A: Swift/UVOT Observations of a Possible Late-Time Brightening
  84. GRB 100807A: P200 Infrared Observations
  85. GRB100807A: optical observation in CrAO
  86. GRB 100805A: optical observation in CrAO
  87. GRB 100807A: Swift XRT refined analysis
  88. GRB 100807A: P60 Optical Afterglow Discovery
  89. GRB 100807A: Swift/UVOT Upper Limits
  90. GRB 100807A: Enhanced Swift-XRT position
  91. GRB 100807A: Swift-BAT refined analysis
  92. GRB 100807A: ROTSE-III Optical Limits
  93. GRB 100807A: Swift detection of a burst
  94. GRB 100805A: Early RAPTOR Observations
  95. GRB 100805A: Swift/UVOT Observations of the Optical Afterglow
  96. Swift-BAT trigger 430975 is not a burst
  97. GRB 100805A: Swift-BAT refined analysis
  98. GRB 100805A: Swift-XRT Refined Analysis
  99. Trigger 430975: Swift detection of a possible burst
  100. GRB 100805A: I-band detection from 1.23m CAHA telescope.

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