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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"

18667 results found.

  1. GRB050824: MASTER final analysis of the OT observations
  2. Possible GRB050825:MASTER optical observations
  3. Swift-BAT trigger 152038 is definitely not a GRB
  4. GRB050824: CORRECTION to UVOT observing times
  5. Swift-BAT trigger 152038 is probably not a GRB
  6. GRB050824: Swift/UVOT detection of fading afterglow
  7. GRB050824: decay of the XRT light curve and updated X-ray spectrum
  8. GRB050824, I-band imaging
  9. GRB 050822: refined XRT analysis
  10. GRB 050824: XRT refined analysis and possible afterglow detection
  11. GRB 050824: BAT refined analysis of a soft weak burst
  12. GRB050824: MASTER:OT decay
  13. GRB050824: MASTER observation OT
  14. GRB050805a: MASTER optical candidat
  15. GRB 050824: ROTSE-III Optical Limits
  16. GRB050824: Swift-BAT detection of a burst
  17. GRB050822: Swift/UVOT upper limits
  18. GRB 050820A BAT observations of second, larger episode of emission
  19. GRB 050822: Swift-BAT refined analysis
  20. GRB 050820a - corrections to GCN 3846
  21. Swift/UVOT UV Photometry of GRB 050820B
  22. GRB 050822: ROTSE-III Prompt Optical Limits
  23. GRB 050822: Swift detection of a long burst
  24. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  25. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  26. GRB050820a BVRcIc field photometry
  27. GRB050820B XMM-Newton observation
  28. GRB 050820a: NIR Observations by WIRO
  29. GRB 050820B: Swift XRT position
  30. GRB050820B: Refined analysis of the Swift-BAT burst
  31. GRB050820B: BAT-Swift detection of a bright GRB
  32. Swift/UVOT photometry of GRB050820
  33. GRB050820: refined XRT analysis
  34. GRB 050820: Early RAPTOR detections
  35. GRB 050820 Swift-BAT refined analysis
  36. GRB050819: refined XRT analysis
  37. GRB 050820: Swift detection of a GRB
  38. GRB050820: Optical afterglow from P60
  39. GRB 050819 Swift-BAT refined analysis
  40. GRB050819: Swift XRT position
  41. GRB050819: Swift-BAT detection of a weak burst
  42. Swift-BAT trigger 150993 is not a GRB
  43. Swift Trigger 150823 is HETE J1900.1-2455
  44. GRB050817: Swift-BAT Detection of a burst
  45. GRB050815: Optical afterglow detection by Swift UVOT
  46. GRB050815: XRT refined analysis
  47. GRB050815: Refined analysis of the Swift-BAT burst
  48. GRB 050815: ROTSE-III Optical Limits
  49. GRB050815: Swift XRT afterglow localization
  50. GRB050815: Swift-BAT detection of a burst
  51. GRB050814: P60 Optical Afterglow Candidate
  52. GRB 050814: XRT refined analysis
  53. GRB050814: SWIFT/UVOT observation
  54. GRB050814: Refined analysis of the Swift-BAT burst
  55. GRB 050814: Swift XRT Afterglow Localization
  56. GRB 050814: Swift detection of a burst
  57. GRB050813, SDSS pre-burst observations
  58. GRB 050813: KAIT optical limit
  59. GRB 050813: Swift-BAT refined analysis
  60. GRB050813: SWIFT/UVOT observation
  61. GRB 050813: Swift XRT afterglow localization
  62. GRB 050813: Possible Short Swift-BAT GRB
  63. GRB050813 (Swift 150139): P60 Observations
  64. Swift-BAT trigger 150131 is not a GRB
  65. GRB050805b: CrAO optical limit
  66. GRB050805a : Null detection report
  67. Swift-BAT trigger 149118 is very likely not a GRB
  68. Retraction of Swift Trigger 149131 (GRB 050805B)
  69. GRB 050805b: OHP optical limits
  70. GRB 050805b: TAROT optical limits
  71. GRB050805b: MASTER optical observations
  72. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  73. GRB050805a: MASTER optical candidat
  74. Swift-BAT trigger 149118 is probably not a GRB
  75. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  76. GRB 050803: Swift-BAT refined analysis
  77. GRB050803: MASTER further analys
  78. GRB 050803: early Swift XRT analysis results
  79. GRB 050803: TAROT optical limits
  80. GRB050803: MASTER optical observations
  81. GRB050803: Swift-BAT detection of a very long burst
  82. GCN GRB observation 050713A
  83. GRB 050802: Swift/UVOT optical and UV detections
  84. GRB050802 radio non-detection
  85. GRB 050730: OHP optical observations
  86. GRB 050802: early Swift XRT analysis results
  87. GRB 050802: Swift/UVOT observations
  88. GRB 050802: Swift-BAT refined analysis
  89. GRB 050802: XRT position
  90. GRB 050802: Swift Gamma-ray Burst
  91. GRB050801: Swift/UVOT Optical and UV detections
  92. GCN 050801: early Swift XRT analysis results
  93. GRB 050801: Swift-BAT refined analysis
  94. GRB 050801, afterglow observations
  95. GRB 050730, corrected photometry and break?
  96. GRB 050801: ROTSE-III Early Afterglow Break
  97. GRB050801: Swift-BAT detection of a burst
  98. GRB050801: GCN XRT position is incorrect
  99. GRB 050801: ROTSE-III Detection of Possible Counterpart
  100. GRB 050730: XRT refined analysis

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