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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"

35428 results found.

  1. GRB 061202, Swift-BAT refined analysis
  2. GRB 061202: Swift detection of a burst
  3. GRB 061201: Swift XRT Team refined analysis
  4. GRB 061201: VLT optical observations
  5. GRB 061201: Initial UVOT Observations
  6. GRB 061201, Swift-BAT refined analysis of the SHB
  7. GRB 061201: Swift detection of a short hard burst
  8. GRB 061201: Coincidence with a Galaxy Cluster
  9. GRB 061122: GETS observation
  10. GRB 061121, SMARTS optical/IR observations
  11. GRB 061121: flattening of the decay
  12. INT+WFC observations of GRB 061126
  13. GRB 061126: Possible Jet Break
  14. GRB 061121: Second Epoch ATCA Radio Observations
  15. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  16. GRB 061121: ATCA & WSRT Radio Observations
  17. GRB061121: optical observations
  18. GRB 061126: Early Super-LOTIS Observations
  19. GRB 061126: optical observation
  20. GRB 061126: Tautenburg afterglow observations
  21. GRB 061126 : SDSS Pre-Burst Observations
  22. GRB 061126: Swift-XRT refined analysis
  23. GRB 061126: Swift/UVOT Observations
  24. GRB 061126, Swift-BAT refined analysis
  25. GRB 061126: SARA Observations
  26. GRB 061126: Early Detection of the IR Afterglow
  27. GRB 061126: Faulkes Telescope North Optical Observations
  28. GRB 061126: Swift/UVOT Afterglow Detection
  29. GRB 061126: XRT position
  30. GRB 061126: Swift detection of a burst
  31. GRB 061121: MDM Continued Monitoring
  32. GRB 061122: Confirmation of X-ray/Optical Afterglow
  33. GRB 061121: MDM Continuing Optical Decay
  34. GRB061121: optical observations
  35. GRB 061122: Candidate Optical Afterglow
  36. GRB 061121: Ep,i - Eiso correlation
  37. GRB 061121: MDM Optical Decay
  38. GRB061122: Swift/UVOT Optical Observations
  39. GRB 061121: ART detection in Ic
  40. GRB061121: P60 Observations
  41. Radio detection of GRB 061121
  42. GRB061122: Swift-XRT position
  43. Konus-Wind observation of GRB 061122
  44. GRB 061121: MDM Optical Observations
  45. GRB 061121 declared "Burst of Interest" by Swift team
  46. Konus-Wind and Konus-A observations of GRB 061121
  47. INTEGRAL results on GRB 061122
  48. Swift-BAT trigger 239987 is not a GRB
  49. GRB 061122A: a long GRB detected by INTEGRAL
  50. GRB 061121: Swift/UVOT Observations
  51. GRB 061121: Swift-XRT Team Refined Analysis
  52. GRB 061121, Swift-BAT refined analysis
  53. GRB 061121 : Planned XMM-Newton observation
  54. GRB 061121: Optical observation at the KANATA 1.5m telescope
  55. GRB 061121: Faulkes Telescope North Optical Observation
  56. GRB061121: Spectroscopic Redshift
  57. GRB 061121: ROTSE-III Confirmation of Optical Counterpart
  58. GRB 061121: Swift detection of a bright burst with an optical counterpart
  59. GRB 060605: NIR Observations
  60. GRB 050915B: optical afterglow
  61. GRB 060111B: Swift UVOT Refined Magnitudes
  62. GRB061110A: Correction to GCN5817
  63. GRB 061110A: refined R-band analysis
  64. GRB 061110B: NIR Observations
  65. Swift TOO observations of GRB061110A
  66. Swift/UVOT Upper Limits for GRB061110b
  67. Swift/UVOT Upper Limits for GRB061110a
  68. GRB 061110A - VLT tentative redshift
  69. GRB 061110B: Swift XRT refined analysis
  70. GRB 061110B, Swift-BAT refined analysis
  71. GRB 061110B: VLT redshift
  72. GRB061110B: Optical observations at Crni Vrh
  73. GRB 061110B: NOT optical observations
  74. GRB 061110A: Swift XRT refined analysis
  75. GRB 061110B: Swift/XRT position
  76. GRB 061110B : Liverpool Telescope Optical Afterglow Detection
  77. GRB 061110B: Swift-UVOT Initial Observation
  78. GRB 061110A, Swift-BAT refined analysis
  79. GRB 061110B: TAROT Calern observatory optical observations
  80. GRB 061110B: Swift detection of a burst
  81. GRB 061110: NOT observations
  82. GRB 061110: Candidate confirmed
  83. GRB 061110 : Optical afterglow candidate
  84. GRB 061110: ROTSE-III Optical Limits
  85. GRB 061110: Swift detection of a burst
  86. Swift-BAT Trigger 237821 is a Cosmic Ray Shower event
  87. GRB 061109: optical observation
  88. GRB 061109: TAROT Calern observatory optical observations
  89. GRB 061109: Swift detection of a possible burst
  90. GRB061028: MAGIC telescope GeV observation
  91. GRB 061027: TAROT La Silla observatory optical observations
  92. GRB 061007: Third Epoch ATCA Radio Observations
  93. GRB061019: second epoch CrAO observations
  94. GRB 061028: Swift/XRT Astrometry Correction
  95. GRB 061102: Swift/UVOT Magnitude Upper Limits
  96. GRB 061102, XRT refined analysis
  97. GRB 061004: Further VLT/NTT observations
  98. Swift-BAT Trigger 236481 is a Cosmic Ray Shower event
  99. GRB061102B: Super-LOTIS observations
  100. GRB 061028: Optical R passband observations

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