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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"
  1. GRB080623: Swift UVOT followup observations
  2. GRB 080623: Swift-XRT refined analysis
  3. GRB 080623, Swift-BAT refined analysis
  4. GRB 080623: Enhanced Swift-XRT position
  5. GRB 080623: TAROT La Silla observatory optical observations
  6. GRB 080623: Swift/UVOT Non-Detection of an Optical Afterglow
  7. GRB 080623: Swift XRT prompt analysis
  8. GRB 080623: Swift detection of a burst
  9. Swift trigger 314975 is not a GRB
  10. Swift-BAT trigger 314975 possible burst
  11. GRB080607: optical observation
  12. GRB 080603b: optical observation
  13. GRB 070809: Putative host galaxy and redshift
  14. VLA upper limit on INTEGRAL burst GRB 080613A
  15. GRB 0800603A: optical observation
  16. GRB080613B: MITSuME upper limits
  17. GRB080613A: Optical upper limits with Okayama MITSuME telescope
  18. Konus-Wind observation of GRB 080613B
  19. GRB 080603A: optical observations on June 04
  20. GRB 080613A: Swift-XRT detection of the afterglow
  21. GRB080613A: Swift/UVOT Upper Limits
  22. GRB 080613A: GROND Confirmation of the Afterglow Candidate
  23. GRB 080613B: GROND Upper Limits
  24. GRB 080613B - NOT optical and IR nondetections
  25. GRB080613B: Swift/UVOT Upper Limits
  26. GRB 080613B, Swift-BAT refined analysis
  27. GRB 080613B: Swift-XRT refined analysis
  28. GRB 080514B: Spectroscopic constraints and probable host galaxy
  29. GRB 080613B: Swift detection of a burst
  30. GRB 080613: Faulkes Telescope North optical candidate
  31. GRB 080613 : a long GRB detected with INTEGRAL
  32. GRB 080603A: Late-time Keck imaging and spectroscopy
  33. GRB 080603b: optical observation
  34. Swift observations of BAT Slew Survey event (Trigger=010)
  35. GRB 080603A: final Swift-XRT observations.
  36. GRB 080607: AGILE-MCAL observation of the prompt emission
  37. GRB 080603B - TLS 2nd Epoch: Another Break
  38. GRB 080605: TLS 3rd Epoch - Source Confusion
  39. GRB080605: optical observation with the MITSuME-OAO telescope
  40. Konus-Wind observation of GRB 080607
  41. GRB080607: RTT150 optical observations
  42. GRB 080603A: optical observations
  43. GRB 080607: Swift-XRT refined analysis
  44. Swift/UVOT Observations of GRB080607
  45. GRB 080605: optical observations
  46. GRB 080607 KAIT observations
  47. VLA detection of INTEGRAL burst GRB 080603A
  48. Konus-Wind observation of GRB 080605
  49. GRB 080607: Enhanced Swift-XRT position
  50. GRB 080607, Swift-BAT refined analysis
  51. GRB 080605: GROND 2nd epoch observations
  52. GRB 080607 - PAIRITEL NIR detection
  53. GRB 080607: Keck/LRIS spectroscopy and redshift
  54. GRB 080607: Super-LOTIS early observations
  55. GRB 080607: Swift detection of a burst with optical afterglow
  56. GRB 080607: ROTSE-III Detection of Optical Counterpart
  57. GRB 080605: TLS RRM Analysis, Plateau/Rebrightening, Red OT
  58. GRB 080605: Swift-UVOT refined analysis
  59. Possible VLA radio detection on INTEGRAL burst GRB 080603A
  60. GRB 080604: VLA radio upper limit
  61. GRB 080605, Swift-BAT refined analysis
  62. GRB 080603B: VLA radio upper limit
  63. GRB 080605, Swift-BAT refined analysis
  64. GRB 080605: Swift-XRT refined analysis
  65. GRB080605: observation by BOOTES
  66. GRB 080605: MASTER VWF 46 s AT observation
  67. GRB 080605: Enhanced Swift-XRT position
  68. GRB 080605: GROND detection of the optical afterglow candidate
  69. GRB080605: optical observations
  70. GRB 080605: VLT redshift
  71. GRB 080605: Liverpool Telescope optical afterglow candidate
  72. GRB 080605: Swift/UVOT Position of the Optical Afterglow
  73. GRB 080605: TLS RRM Afterglow
  74. GRB 080605: Swift detection of a burst with an optical afterglow
  75. GRB 080603B: PAIRITEL infrared detection
  76. GRB 080603A: PAIRITEL infrared detection
  77. GRB 080604: Xinglong R band observation
  78. GRB 080603A: Xinglong R band observation
  79. GRB 080603B: TLS Afterglow Observation
  80. GRB 080603A: TLS Afterglow Observation
  81. GRB 080604: MITSuME Okayama observation
  82. Swift/UVOT observations of GRB080604
  83. GRB080604: HET redshift retraction
  84. GRB 080604: Gemini-North spectroscopy
  85. GRB 080604, Swift-BAT refined analysis
  86. GRB 080604: Swift-XRT refined analysis
  87. GRB 080603B: Hobby-Eberly Telescope redshift confirmation
  88. GRB 080603B : Xinglong EST observations
  89. GRB 080603B : Liverpool Telescope Observations
  90. Konus-Wind observation of GRB 080603B
  91. GRB 080603B: Swift-XRT refined analysis
  92. GRB 080603A: Swift-XRT detection of the afterglow
  93. GRB 080430: optical observations
  94. GRB 080603B: Swift/UVOT detection of the afterglow
  95. GRB 080604: Enhanced Swift-XRT position
  96. GRB 080603B, Swift-BAT refined analysis
  97. GRB 080604: Hobby-Eberly Telescope spectroscopy
  98. GRB 080603A: Swift/UVOT detection of the afterglow
  99. GRB080603B: RTT150 optical observations, break in light curves
  100. GRB 080604: Early Super-LOTIS Observations

Advanced

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