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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"

4958 results found.

  1. GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
  2. GRB 110414A: Swift detection of a burst
  3. GRB 110411A: PAIRITEL NIR Upper Limits
  4. GRB 110411A: MASTER prompt and follow-up optical limits
  5. GRB 110411A: Swift detection of a burst
  6. GRB 110407A: Swift detection of a burst
  7. GRB 110402A: fading optical afterglow
  8. GRB 110402A: optical observations in Mondy
  9. GRB 110402A: Liverpool Telescope Observations
  10. GRB 110319A: Swift detection of a burst
  11. GRB 110318B: Swift detection of a burst
  12. GRB 110210A: ROVOR Upper Limit
  13. GRB110213A: MITSuME Okayama Optical Observation
  14. GRB 110212A: ROTSE-III Optical Limits
  15. GRB 110212A: Swift detection of a burst
  16. GRB 110201A: optical observations
  17. GRB 110210A: Swift detection of a burst
  18. GRB 110205A : HCT optical observations
  19. GRB 110206A: GROND detection of afterglow candidate
  20. GRB 110206A: UVOT detection of afterglow candidate
  21. GRB 110205A: Lightbuckets Optical Observations
  22. GRB 110205A: Newcastle Observatory Optical Observations
  23. GRB110201A: MITSuME Okayama optical upper limits
  24. GRB 110201A: MASTER optical observations
  25. GRB 110201A: Swift detection of a burst
  26. Swift Trigger 442539 is probably not a GRB
  27. GRB 110112A: MITSuME Akeno and Okayama optical upper limits
  28. GRB 110102A: Swift detection of a burst with an optical detection
  29. GRB101224A: MITSuME Okayama optical upper limits
  30. XRF 101117A, RIMOTS optical upper limits
  31. Konus-Wind observation of GRB 101130A
  32. IPN Localization of GRB101130 (possible short duration burst)
  33. GRB 101030A: Swift detection of a burst
  34. GRB 101020A: Swift detection of a burst
  35. GRB 101017A: Swift detection of a burst with optical counterpart
  36. Swift Trigger 435520 is probably not a GRB
  37. GRB 100925A / MAXI J1659-152: MASTER optical observations
  38. GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope
  39. GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation
  40. MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
  41. GRB 100909A: Faulkes Telescope North afterglow candidate
  42. GRB 100909A: a long GRB detected by INTEGRAL
  43. GRB100906A: detection at 15GHz
  44. GRB100901A: IAO optical upper limits at 4 days after the burst
  45. GRB 100906A: GRAS-007 optical observations
  46. GRB100906A: R band observations
  47. GRB100906A: Optical observations at IAO
  48. GRB100906A: MITSuME Okayama Optical Observation
  49. GRB 100906A: Ondrejov 65cm observations
  50. GRB 100901A: ISON-NM optical observations
  51. GRB100905A: Optical upper limits at IAO
  52. GRB100905A: MITSuME Okayama optical upper limits
  53. GRB 100905A: MASTER Prompt Optical Observations
  54. GRB 100905A: Swift detection of a burst
  55. GRB10901A: Murikabushi telescope observation at 3 days after the burst
  56. GRB100902A: Optical upper limits at IAO
  57. GRB10901A: Optical observations at IAO
  58. IPN Triangulation of the very bright GRB 100829A
  59. GRB 100901A: HCT optical observations
  60. GRB 100901A: Kanata Telescope observation of the optical afterglow
  61. GRB100901A: MITSuME Okayama Optical Observation at 1 day after the burst
  62. GRB 100901A: ISON-NM optical observations
  63. GRB 100901A : HCT optical observations
  64. GRB 100901A: THO optical observations
  65. GRB100901A: MITSuME Okayama Optical Observation
  66. GRB 100901A: optical observation at Mt.Terskol
  67. GRB 100814A: ISON-NM optical observations
  68. GRB 100814A : Liverpool Telescope Observations
  69. GRB 100814A : Lulin optical observation
  70. GRB 100816A : Lulin r'-band observation
  71. GRB 100814A: CQUEAN r- and i-band Observation
  72. GRB 100814A: Swift detection of a burst with an optical afterglow
  73. GRB 100807A: P200 Infrared Observations
  74. GRB 100807A: P60 Optical Afterglow Discovery
  75. GRB 100807A: ROTSE-III Optical Limits
  76. GRB 100807A: Swift detection of a burst
  77. GRB 100802A: NOT optical observation
  78. GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow
  79. GRB 100802A: Swift detection of a burst
  80. GRB 100728A: GROND Detection of the NIR Afterglow Candidate
  81. GRB 100727A: Swift detection of a burst
  82. GRB 100725B: Swift detection of a burst
  83. GRB 100725A: Swift detection of a burst
  84. GRB 100724A, GROND detection of an afterglow candidate
  85. Fermi GBM trigger 300370702 (100709513) is not a GRB
  86. GRB 100704A: Swift detection of a burst
  87. GRB 100526A: Gemini/NIRI afterglow confirmation and host galaxy
  88. GRB100625A: GROND confirmation of constant source
  89. GRB 100625A Gemini-South 2nd epoch imaging
  90. GRB 100621A MOA-II optical limit
  91. GRB 100621A: VLT/X-shooter redshift
  92. GRB 100621A: ROTSE-III Optical Limits
  93. GRB 100615A: Swift detection of a burst
  94. GRB 100606A: Swift detection of a burst
  95. GRB100526B: GROND Upper limits
  96. GRB 100526A: Swift detection of a burst
  97. GRB 100522A: GROND observations, upper limits
  98. GRB 100522A: Swift detection of a burst
  99. GRB 100518A: GROND afterglow observation and photo-z
  100. GRB 100514A: optical afterglow confirmation

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