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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. GRB 120102A: Swift detection of a burst with an optical counterpart
  2. GRB 111225A: optical observations in CrAO
  3. GRB 111228A, optical observations
  4. GRB 111228A: LOAO Optical Observation
  5. Konus-Wind observation of GRB 111228A
  6. GRB 111228A: MASTER-Net optical photometry
  7. GRB 111228A: correction for GCN 12787
  8. GRB 111228A: Optical and NIR observations with Kanata telescope
  9. GRB 110915A, the review of the sky area in plate archives
  10. GRB 111228A: correction to GCN 12784
  11. GRB 111228A: SMARTS optical/IR afterglow observations
  12. GRB 111229A: Swift/UVOT Detection
  13. GRB 111229A: Faulkes Telescope South observations
  14. GRB 111229A: Swift-XRT refined Analysis
  15. GRB 111229A: Enhanced Swift-XRT position
  16. GRB 111228A: Continued Skynet PROMPT/Dolomiti Optical Observations
  17. GRB111228A: Further GMG observations
  18. GRB 111229A: Gemini-South Redshift
  19. GRB 111229A: Swift-BAT refined analysis
  20. GRB 111229A: GROND afterglow candidate
  21. GRB 111229A: Swift detection of a burst
  22. GRB 111228A: Liverpool Telescope Observations
  23. GRB 111225A: Lightbuckets Optical Observations
  24. GRB 111228A: P60 Observations
  25. GRB 111228A: X-shooter spectroscopy
  26. GRB 111228A: T100 observations
  27. GRB111228A: MITSuME Akeno photometry of the optical afterglow
  28. GRB 111228A: GMG optical observation
  29. GRB 111228A: Swift-XRT refined Analysis
  30. GRB 111228A: NOT redshift
  31. GRB111228A: TNG spectroscopy analysis
  32. FERMI GRB111228.45: MASTER observations
  33. GRB 111228A: Gemini South Redshift
  34. GRB 111228A: PAIRITEL NIR Detection
  35. GRB 111228A: MMT Redshift
  36. GRB 111228A: TAROT La Silla observatory observations
  37. GRB 111228A: GROND observations
  38. GRB 111228A: MASTER OT observations
  39. GRB111228A: Errata of MITSuME Okayama about GRB name in GCNC 12743
  40. GRB 111228A: GRAS017 optical observations
  41. GRB 111228A: IAC80 BVI-band observations
  42. GRB 111228A: Swift/UVOT Detection
  43. GRB 111228A: Skynet/Dolomiti Optical Observations
  44. GRB 111228A: NOT optical observation
  45. GRB 111228A, Swift-BAT refined analysis
  46. GRB 111228A: optical observations
  47. GRB 111228A: Enhanced Swift-XRT position
  48. GRB 111228A: TAROT Calern observatory. OT decay stopped
  49. GRB 111228A, optical observations
  50. GRB 111228A: Fermi GBM observation
  51. GRB111228A: MITSuME Okayama Optical Observation
  52. GRB 111228A: TAROT Calern observatory. OT seems still bright
  53. GRB 111228A: Possible host galaxy in the SDSS arhive
  54. GRB 111225A, optical observations
  55. XMM-Newton observation of the short GRB 111020A
  56. GRB 111228A: Xinglong TNT confirms the optical afterglow
  57. GRB 111228A: Swift detection of a burst with an optical counterpart
  58. GRB 111205A: optical observations
  59. GRB 111225A: Swift/UVOT Observations
  60. GRB 111215A: Keck/LRIS Imaging
  61. GRB 111225A: Keck/LRIS Afterglow Photometry
  62. GRB 111222A : Suzaku WAM observation of the prompt emission
  63. GRB 111225A: PAIRITEL NIR Upper Limits
  64. GRB111225A: MITSuME Okayama optical upper limits
  65. GRB 111225A: GRT Optical Observation
  66. GRB 111225A: 1.23m CAHA optical observations
  67. GRB 111225A: Swift-XRT refined Analysis
  68. GRB 111225A, Swift-BAT refined analysis
  69. GRBv111225A: Xinglong TNT optical afterglow
  70. GRB 111225A: Enhanced Swift-XRT position
  71. GRB 111225A: Super-LOTIS early detection
  72. GRB 111225A: TAROT Calern observatory optical detection
  73. GRB 111225A: TAROT Calern observatory optical observations
  74. GRB 111225A: Swift detection of a burst with an optical counterpart
  75. GRB111222A: GMG optical observation
  76. GRB 111222A: Xinglong TNT observation
  77. GRB 111222A: Swift/UVOT Observations
  78. GRB 111222A: Swift-XRT observations
  79. Konus-Wind observation of GRB 111222A
  80. IPN Triangulation of GRB 111222A (short/hard/intense)
  81. GRB 111210A: optical upper limit of Mt. Terskol observatory
  82. Trigger 510075 is not a GRB
  83. GRB 111215A: EVLA observations
  84. GRB111215A: CARMA Detection
  85. XRT GRB Catalogue now live and online
  86. GRB 111103B: optical upper limit
  87. GRB 110820A: optical observations in Maidanak observatory
  88. GRB 111103A: optical upper limit of Mt. Terskol observatory
  89. GRB 111215B: Suzaku WAM observation of the prompt emission
  90. GRB 111211A: optical ovservations at Mt. Terskol observatory
  91. GRB111215A: optical upper limit
  92. GRB 111215B: Swift/UVOT Upper Limits
  93. Konus-Wind observation of GRB 111215B
  94. GRB 111215B: Swift-XRT observations
  95. GRB 111205A: Confirmation of X-ray Afterglow
  96. IPN Triangulation of GRB 111215B (long/intense)
  97. GRB111215A: Pre-Outburst Palomar 48 inch Imaging
  98. GRB 111215A: WHT, LT and NOT imaging
  99. GRB 111215A: TNG K-band observations
  100. GRB 111215A: MITSuME Okayama Optical upper limits

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