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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"

31632 results found.

  1. GRB 061210: MDM Observation
  2. GRB 061210, Swift-BAT refined analysis of the SHB
  3. GRB 061210: Swift-BAT detection of a short burst
  4. Optical Afterglow observations of GRB 061126
  5. GRB061126: optical observations
  6. GRB 060926: MASTER: discovery of the optical flare
  7. GRB061126: update on the Swift-XRT afterglow light curve
  8. Corrections for Swift/UVOT Exposure Times for GRBs 061110B and 061121
  9. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  10. GRB 061202: TORTOREM optical upper limits
  11. GRB 061201: VLT optical decay
  12. GRB 061201: SOAR Confirmation of Candidate Afterglow
  13. GRB061126 : NMSU 1.0m observations
  14. GRB 061202: Swift XRT refined analysis
  15. GRB061202: FRAM early follow-up limit
  16. Konus-Wind observation of GRB 061201
  17. GRB061202: optical/NIR observations with REM
  18. GRB061202: Swift/UVOT Upper Limits
  19. GRB 061202, Swift-BAT refined analysis
  20. GRB 061201: Swift XRT Team refined analysis
  21. GRB 061201: VLT optical observations
  22. GRB 061201: Initial UVOT Observations
  23. GRB 061201, Swift-BAT refined analysis of the SHB
  24. GRB 061122: GETS observation
  25. GRB 061121, SMARTS optical/IR observations
  26. GRB 061121: flattening of the decay
  27. INT+WFC observations of GRB 061126
  28. GRB 061126: Possible Jet Break
  29. GRB 061121: Second Epoch ATCA Radio Observations
  30. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  31. Swift XRT on-board boresight update
  32. GRB 061121: ATCA & WSRT Radio Observations
  33. GRB061121: optical observations
  34. GRB 061126: Early Super-LOTIS Observations
  35. GRB 061126: optical observation
  36. RHESSI Spectrum of GRB061126
  37. GRB 061126: Tautenburg afterglow observations
  38. GRB061126: Optical afterglow observations from MIRO
  39. GRB061126: Optical afterglow observations from MIRO
  40. GRB 061126 : SDSS Pre-Burst Observations
  41. GRB 061126: Swift-XRT refined analysis
  42. GRB 061126: Swift/UVOT Observations
  43. GRB 061126, Swift-BAT refined analysis
  44. GRB 061126: SARA Observations
  45. GRB 061126: Early Detection of the IR Afterglow
  46. GRB 061126: Faulkes Telescope North Optical Observations
  47. GRB 061121: MDM Continued Monitoring
  48. GRB 061122: Confirmation of X-ray/Optical Afterglow
  49. GRB 061121: MDM Continuing Optical Decay
  50. GRB061121: optical observations
  51. GRB 061122: Candidate Optical Afterglow
  52. GRB 061121: Ep,i - Eiso correlation
  53. GRB 061121: MDM Optical Decay
  54. GRB061122: Swift/UVOT Optical Observations
  55. GRB 061121: ART detection in Ic
  56. GRB061121: P60 Observations
  57. Radio detection of GRB 061121
  58. GRB061122: Swift-XRT position
  59. Konus-Wind observation of GRB 061122
  60. GRB 061121: MDM Optical Observations
  61. GRB 061121 declared "Burst of Interest" by Swift team
  62. RHESSI Spectrum of GRB061121
  63. Konus-Wind and Konus-A observations of GRB 061121
  64. INTEGRAL results on GRB 061122
  65. GRB 061121: Swift/UVOT Observations
  66. GRB 061121: Swift-XRT Team Refined Analysis
  67. GRB 061121, Swift-BAT refined analysis
  68. GRB061121, optical observation
  69. GRB 061121: Optical observation at the KANATA 1.5m telescope
  70. GRB 061121: Faulkes Telescope North Optical Observation
  71. GRB061121: Spectroscopic Redshift
  72. GRB 061121: ROTSE-III Confirmation of Optical Counterpart
  73. GRB 060605: NIR Observations
  74. GRB 050915B: optical afterglow
  75. GRB 060111B: Swift UVOT Refined Magnitudes
  76. GRB061110A: Correction to GCN5817
  77. GRB 061110A: refined R-band analysis
  78. GRB 061110B: NIR Observations
  79. Swift/UVOT Upper Limits for GRB061110b
  80. Swift/UVOT Upper Limits for GRB061110a
  81. GRB 061110B: Swift XRT refined analysis
  82. GRB 061110B, Swift-BAT refined analysis
  83. GRB 061110B: VLT redshift
  84. GRB 061110B: NOT optical observations
  85. GRB 061110A: Swift XRT refined analysis
  86. GRB 061110B: Swift/XRT position
  87. GRB 061110B : Liverpool Telescope Optical Afterglow Detection
  88. GRB 061110A, Swift-BAT refined analysis
  89. GRB 061110: ROTSE-III Optical Limits
  90. Swift-BAT Trigger 237821 is a Cosmic Ray Shower event
  91. GRB 061109: optical observation
  92. GRB061028: MAGIC telescope GeV observation
  93. GRB 061007: Third Epoch ATCA Radio Observations
  94. GRB061019: second epoch CrAO observations
  95. GRB 061028: Swift/XRT Astrometry Correction
  96. GRB 061102: Swift/UVOT Magnitude Upper Limits
  97. GRB 061102, XRT refined analysis
  98. GRB 061004: Further VLT/NTT observations
  99. Swift-BAT Trigger 236481 is a Cosmic Ray Shower event
  100. GRB061102B: Super-LOTIS observations

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