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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"

24979 results found.

  1. GRB 060108: VLT K-band observations
  2. GRB 060111: TAROT optical observation
  3. GRB 060111: Swift detection of a burst
  4. GRB 060110: Mitsume optical observations
  5. GRB 060110: Swift-BAT refined analysis
  6. GRB 060109: Swift-BAT refined analysis
  7. GRB 060108: z-band imaging from Gemini-North
  8. GRB 060110a: RAPTOR detection of early optical emission.
  9. GRB 060110: UKIRT K-band observations
  10. GRB 060110: IR Candidate Afterglow
  11. GRB060110, optical observation
  12. GRB 060110: Correction
  13. Correction to GRB 060109 XRT analysis
  14. GRB 050110: IR Observations
  15. GRB 060109: Refined Swift-XRT analysis
  16. GRB 060109: Swift/UVOT upper limits
  17. GRB060109, optical observation
  18. GRB 060108: ISAS early observations and near IR upper limit
  19. GRB060108: P200 Ks Observations
  20. GRB 060108: early UKIRT K-band observations
  21. GRB 060108: a dark burst?
  22. GRB 060108: Refined XRT analysis
  23. GRB 060108: VLT J-band observations
  24. GRB 060108: Mitsume optical observations
  25. GRB 060108: Swift/UVOT upper limits
  26. GRB 060105: quick look analysis of the Suzaku/XIS afterglow observation
  27. GRB060108: SDSS pre-burst observations
  28. GRB060108: Faulkes Telescope observation
  29. GRB060108, optical observation
  30. GRB 060108: Refined analysis of the Swift-BAT burst
  31. GRB060108: Swift detection of its 100th GRB
  32. GRB 060105: ISAS observations and near IR upper limit
  33. GRB 060105: Swift/UVOT upper limits
  34. GRB 060105: Mitsume optical observations
  35. GRB 060105: BAT refined analysis
  36. GRB 060105: XRT refined analysis
  37. GRB060105: Suzaku-XIS and -HXD observation plan
  38. GRB060105, optical observation
  39. GRB060105: Swift detection of a bright long burst
  40. Swift-BAT trigger 175653 is probably not a GRB
  41. GRB 060102: Swift-BAT refined analysis
  42. GRB 060102: Swift-BAT detection of a burst
  43. GRB 051221B: Optical Observations with Kuiper 1.54m
  44. GRB 051227: Likely host galaxy underlying afterglow position
  45. GRB 051227: optical observation
  46. GRB 051227: optical afterglow
  47. GRB 051227: Magellan r'-band Imaging/Astrometry
  48. GRB 051227: refined analysis of VLT images
  49. GRB 051227: P60 Observations
  50. GRB 051227: MDM Observation
  51. GRB 051227: R-band object in the XRT error circle
  52. GRB 051227: XRT refined analysis
  53. GRB 051227: Further analysis of the Swift-BAT burst
  54. GRB 051227: Refined analysis of the Swift-BAT burst
  55. GRB051227: SDSS pre-burst observations
  56. GRB 051227, optical observation
  57. GRB051117B: optical observation
  58. Konus-Wind observation of GRB 051221A
  59. GRB051221A: Suzaku WAM observation of the prompt emission
  60. GRB 051221A: MDM Optical Observations
  61. GRB051016: analysis of the XMM-Newton observation
  62. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  63. GRB 051221B: TAROT optical limits
  64. GRB 051221B: Refined analysis of the Swift-BAT burst
  65. GRB 051221B: BOOTES optical observations.
  66. Swift-BAT detection of a possible burst
  67. GRB 051221: Swift XRT refined analysis
  68. GRB 051221: Swift/UVOT upper limits
  69. GRB 051221: No variability in Gemini data
  70. GRB 051221: Improved astrometry of the IR counterpart
  71. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  72. GRB 051221: Swift detection of a bright short burst
  73. Swift detection of an RS CVn flare star
  74. GRB051211A: possible optical candidate
  75. GRB 051215: near-infrared observations
  76. GRB051215 - SDSS pre-burst observations
  77. GRB 051215: Swift detection of a possible burst
  78. GRB051105: optical observations
  79. GRB 051213: Swift-BAT refined analysis
  80. GRB051211B: XRT refined analysis
  81. GRB 051211B, optical observation
  82. GRB 051211A: Swift/UVOT upper limits
  83. GRB 051211B: Swift/UVOT upper limits
  84. GRB 051211A,optical observation
  85. GRB051211B: Liverpool Telescope observation
  86. GRB051211b: P60 Observations
  87. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  88. GRB 051210: Swift/UVOT upper limits
  89. GRB 051210: Magellan Imaging
  90. GRB 051211: TAROT optical limits
  91. GRB 051211B: a possible optical detection by TAROT
  92. GRB 051211:IAC80 optical observations
  93. GRB 051210: SALT detection limit
  94. GRB 051210: Swift XRT refined analysis
  95. GRB 051210: FRAM early limit
  96. GRB 051210: Swift-BAT refined analysis of a short burst
  97. GRB051210: Swift UVOT Observation
  98. GRB 051210: Swift detection of a burst
  99. An extraordinary long burst on December 3 from SGR1806-20
  100. Possible resuming of the SGR 1806-20 activity

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