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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"

5814 results found.

  1. GRB 061126: optical observation
  2. GRB 061126: Swift/UVOT Observations
  3. GRB061121: optical observations
  4. GRB 061121: Swift/UVOT Observations
  5. GRB 061121: Swift-XRT Team Refined Analysis
  6. GRB061121, optical observation
  7. GRB 061121: Faulkes Telescope North Optical Observation
  8. GRB 061121: ROTSE-III Confirmation of Optical Counterpart
  9. GRB 061121: Swift detection of a bright burst with an optical counterpart
  10. GRB061110B: Optical observations at Crni Vrh
  11. GRB 061110A: Swift XRT refined analysis
  12. GRB 061110: Swift detection of a burst
  13. GRB 061109: Swift detection of a possible burst
  14. GRB 061102, XRT refined analysis
  15. GRB 061028: Swift detection of a burst
  16. GRB 061021: Swift/UVOT Observation
  17. GRB 061021: Swift detection of a burst
  18. GRB 060930: MARGE Optical Limits
  19. GRB 061007: Correction to GCN 5712
  20. GRB 061007: Swift detection of a burst with an optical counterpart
  21. GRB 060930: ROTSE-III Optical Limits
  22. GRB 060930: A long X-ray rich GRB detected by INTEGRAL
  23. GRB060929: Swift-XRT refined analysis.
  24. GRB 060927: Swift/UVOT Optical Observations
  25. GRB 060927: Xinglong TNT optical observations
  26. GRB 060926: MASTER: first minutes decay
  27. GRB 060926: MASTER OT alert observation
  28. GRB 060926: MASTER optical observation
  29. GRB060919: Swift/UVOT optical observations
  30. GRB 060919: TAROT optical observations
  31. GRB 060908: REM optical prompt observation
  32. GRB 060904b: SMARTS optical/IR afterglow observations
  33. GRB 060904B: RTT150 optical observations
  34. GRB060904A: Swift/UVOT optical observations
  35. GRB 060904B: Optical observations at Crni Vrh
  36. GRB 060904B: TAROT optical counterpart observations
  37. GRB 060904: TAROT optical observations
  38. 060901: Swift UVOT followup observations
  39. GRB 060901: SMARTS optical/IR observations
  40. Swift-BAT trigger 226614 is not a GRB
  41. GRB 060826(?): Swift detection of a possible burst
  42. GRB 060729, SMARTS optical/IR observations
  43. GRB 060814: Possible IR counterpart
  44. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  45. GRB 060729: An update on the Swift XRT and UVOT observations
  46. GRB 060805B: XRT Team Analysis
  47. GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
  48. IPN triangulation of GRB060805B
  49. GRB 060729 redshift
  50. GRB 060719: Swift detection of a burst
  51. GRB 060717: Swift detection of a burst
  52. GRB060714: optical observations
  53. GRB 060605: SkyNet Optical Limits
  54. GRB 060708: Swift detection of a burst with an UVOT countpart
  55. GRB 060614: SMARTS host galaxy observations
  56. GRB 060602A: Swift/XRT analysis
  57. GRB 060607B: Swift detection of a burst
  58. GRB 060607: Swift detection of a burst with bright optical counterpart
  59. GRB 060522: PROMPT Optical Limits
  60. GRB 060604: Swift detection of a burst with possible optical counterpart
  61. GRB060602A: optical observations(/transient?)
  62. GRB060602 - SDSS Pre-Burst Observations
  63. GRB060526: Optical counterpart from MIRO
  64. GRB 060526: Optical Flare
  65. GRB 060526: MDM-2.4m Observations
  66. GRB 060510A: Swift/UVOT Detection of an Optical Afterglow
  67. GRB060510A: XRT refined analysis
  68. GRB060510 - SDSS Pre-Burst Observations
  69. GRB 060510B: Swift detection of a burst
  70. GRB 060510: Swift detection of a burst with optical transient
  71. GRB 060502B MDM Follow-up Observation
  72. GRB 060502: Swift detection of a burst with an optical counterpart
  73. GRB 060501: MDM Observations
  74. GRB060501: Super-LOTIS observations
  75. GRB060501: P60 imaging and afterglow candidate
  76. GRB060501: Swift XRT position
  77. GRB 060428B: KAIT observations
  78. GRB060427:MASTER optical limit
  79. GRB 060428B: Swift detection of a burst
  80. GRB 060428: Swift detection of a burst
  81. GRB 060421: TTT Observations
  82. GRB(?) 060421: Swift detection of a burst
  83. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  84. GRB 060413: XRT refined analysis
  85. SGR 1900+14: BAT observations
  86. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  87. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  88. GRB 060322: Confirmation of Swift XRT afterglow
  89. GRB 060322: Swift-BAT detection of a 200-sec burst
  90. GRB060219: optical observation
  91. GRB 060306: Swift detection of a bright burst
  92. GRB 060218/SN 2006aj: WIRO optical observations
  93. GRB 060211B: Skynet Observations
  94. GRB 060213: optical afterglow candidate
  95. GRB060213: Swift XRT observations and possible afterglow candidate
  96. GRB060213: MASTER final result
  97. GRB060213:_MASTER_optical_observation
  98. GRB 060213: IPN localization
  99. GRB060121: optical observations
  100. GRB 060211: ROTSE-III Optical Limits

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