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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"

31727 results found.

  1. GRB 060926: MASTER: discovery of the optical flare
  2. GRB061126: update on the Swift-XRT afterglow light curve
  3. Corrections for Swift/UVOT Exposure Times for GRBs 061110B and 061121
  4. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  5. GRB 061202: TORTOREM optical upper limits
  6. GRB 061201: VLT optical decay
  7. GRB 061201: SOAR Confirmation of Candidate Afterglow
  8. GRB061126 : NMSU 1.0m observations
  9. GRB 061202: Swift XRT refined analysis
  10. GRB061202: FRAM early follow-up limit
  11. Konus-Wind observation of GRB 061201
  12. GRB061202: optical/NIR observations with REM
  13. GRB061202: Swift/UVOT Upper Limits
  14. GRB 061202, Swift-BAT refined analysis
  15. GRB 061201: Swift XRT Team refined analysis
  16. GRB 061201: VLT optical observations
  17. GRB 061201: Initial UVOT Observations
  18. GRB 061201, Swift-BAT refined analysis of the SHB
  19. GRB 061122: GETS observation
  20. GRB 061121, SMARTS optical/IR observations
  21. GRB 061121: flattening of the decay
  22. INT+WFC observations of GRB 061126
  23. GRB 061126: Possible Jet Break
  24. GRB 061121: Second Epoch ATCA Radio Observations
  25. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  26. Swift XRT on-board boresight update
  27. GRB 061121: ATCA & WSRT Radio Observations
  28. GRB061121: optical observations
  29. GRB 061126: Early Super-LOTIS Observations
  30. GRB 061126: optical observation
  31. RHESSI Spectrum of GRB061126
  32. GRB 061126: Tautenburg afterglow observations
  33. GRB061126: Optical afterglow observations from MIRO
  34. GRB061126: Optical afterglow observations from MIRO
  35. GRB 061126 : SDSS Pre-Burst Observations
  36. GRB 061126: Swift-XRT refined analysis
  37. GRB 061126: Swift/UVOT Observations
  38. GRB 061126, Swift-BAT refined analysis
  39. GRB 061126: SARA Observations
  40. GRB 061126: Early Detection of the IR Afterglow
  41. GRB 061126: Faulkes Telescope North Optical Observations
  42. GRB 061121: MDM Continued Monitoring
  43. GRB 061122: Confirmation of X-ray/Optical Afterglow
  44. GRB 061121: MDM Continuing Optical Decay
  45. GRB061121: optical observations
  46. GRB 061122: Candidate Optical Afterglow
  47. GRB 061121: Ep,i - Eiso correlation
  48. GRB 061121: MDM Optical Decay
  49. GRB061122: Swift/UVOT Optical Observations
  50. GRB 061121: ART detection in Ic
  51. GRB061121: P60 Observations
  52. Radio detection of GRB 061121
  53. GRB061122: Swift-XRT position
  54. Konus-Wind observation of GRB 061122
  55. GRB 061121: MDM Optical Observations
  56. GRB 061121 declared "Burst of Interest" by Swift team
  57. RHESSI Spectrum of GRB061121
  58. Konus-Wind and Konus-A observations of GRB 061121
  59. INTEGRAL results on GRB 061122
  60. GRB 061121: Swift/UVOT Observations
  61. GRB 061121: Swift-XRT Team Refined Analysis
  62. GRB 061121, Swift-BAT refined analysis
  63. GRB061121, optical observation
  64. GRB 061121: Optical observation at the KANATA 1.5m telescope
  65. GRB 061121: Faulkes Telescope North Optical Observation
  66. GRB061121: Spectroscopic Redshift
  67. GRB 061121: ROTSE-III Confirmation of Optical Counterpart
  68. GRB 060605: NIR Observations
  69. GRB 050915B: optical afterglow
  70. GRB 060111B: Swift UVOT Refined Magnitudes
  71. GRB061110A: Correction to GCN5817
  72. GRB 061110A: refined R-band analysis
  73. GRB 061110B: NIR Observations
  74. Swift/UVOT Upper Limits for GRB061110b
  75. Swift/UVOT Upper Limits for GRB061110a
  76. GRB 061110B: Swift XRT refined analysis
  77. GRB 061110B, Swift-BAT refined analysis
  78. GRB 061110B: VLT redshift
  79. GRB 061110B: NOT optical observations
  80. GRB 061110A: Swift XRT refined analysis
  81. GRB 061110B: Swift/XRT position
  82. GRB 061110B : Liverpool Telescope Optical Afterglow Detection
  83. GRB 061110A, Swift-BAT refined analysis
  84. GRB 061110: ROTSE-III Optical Limits
  85. Swift-BAT Trigger 237821 is a Cosmic Ray Shower event
  86. GRB 061109: optical observation
  87. GRB061028: MAGIC telescope GeV observation
  88. GRB 061007: Third Epoch ATCA Radio Observations
  89. GRB061019: second epoch CrAO observations
  90. GRB 061028: Swift/XRT Astrometry Correction
  91. GRB 061102: Swift/UVOT Magnitude Upper Limits
  92. GRB 061102, XRT refined analysis
  93. GRB 061004: Further VLT/NTT observations
  94. Swift-BAT Trigger 236481 is a Cosmic Ray Shower event
  95. GRB061102B: Super-LOTIS observations
  96. GRB 061028: Optical R passband observations
  97. GRB 061102, Swift-BAT refined analysis
  98. GRB 061028: VLA Observation
  99. GRB 061004: Swift/XRT Astrometry Correction
  100. GRB 060801: Swift/XRT Astrometry Correction

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