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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"

24995 results found.

  1. GRB 060428B: spectroscopy
  2. GRB 060502B: optical observations
  3. GRB 060502B: AROMA refined photometric calibration
  4. GRB 060502B MDM Follow-up Observation
  5. GRB 060502b: Gemini imaging and spectroscopy
  6. GRB060502A, optical observation
  7. GRB 060502B: Swift/UVOT upper limits
  8. GRB 060502A: Swift/UVOT source detection
  9. GRB 060502B: MDM Optical Observation
  10. GRB 060502B: Refined analysis of the Swift-BAT short burst
  11. GRB060502B: Swift XRT Team refined analysis
  12. GRB 060501: P60 Observations and Candidate Retraction
  13. GRB 060502B: Xinglong optical observation
  14. GRB060502: Swift-XRT refined analysis
  15. GRB 060502: Swift-BAT refined analysis
  16. GRB060501: Swift UVOT followup observations
  17. GRB 060502: P60 Afterglow Confirmation
  18. GRB 060502: Swift detection of a burst with an optical counterpart
  19. GRB060501: P60 imaging and afterglow candidate
  20. GRB 060501: Refined analysis of the Swift-BAT burst
  21. GRB060428B - SDSS Pre-Burst Observations
  22. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  23. GRB 060428B: MDM Observations
  24. GRB060428B: Swift XRT Team refined analysis
  25. GRB 060427B: IPN localization of a short hard burst
  26. GRB 060428B: Refined analysis of the Swift-BAT burst
  27. GRB 060428B: Xinglong I-band limit
  28. GRB 051117A: Bright host galaxy not confirmed
  29. GRB060428A: Swift/UVOT observations.
  30. GRB060428B, optical observation
  31. GRB 060428A: Refined analysis of the Swift-BAT burst
  32. GRB 060428b : Kiso R-band limit
  33. GRB 060428b: Optical afterglow candidate
  34. GRB060428A: Swift XRT Team refined analysis
  35. GRB 060428B: Swift detection of a burst
  36. GRB 060427: NIR observations
  37. GRB060427: Xinglong optical Observations
  38. GRB 060428: Swift detection of a burst
  39. GRB 060427: Swift/UVOT upper limits.
  40. GRB 060427: Refined analysis of the Swift-BAT burst
  41. GRB060427: Swift XRT Team refined analysis
  42. GRB060418: Swift XRT Team Further Refined Analysis
  43. GRB060425:MASTER survey observations
  44. GRB 060427, optical observation
  45. GRB 060427: Swift detection of a burst
  46. GRB060418: Further Analysis of MIKE Spectroscopy
  47. GRB 060424: Refined analysis of the Swift-BAT burst
  48. GRB 060421: TTT Observations
  49. GRB060421: Swift/UVOT observations
  50. GRB 060421: Swift-BAT Refined Analysis
  51. GRB 060421: Swift-XRT refined analysis
  52. GRB 060418: prediction of t_break
  53. GRB(?) 060421: Swift detection of a burst
  54. Erratum of GCN 4983 for GRB 060418 IR follow-up
  55. GRB 060418 : IR afterglow observations
  56. GRB 060418: Radio Observations
  57. GRB060418, BVRcIc field calibration
  58. GRB060418: Swift/UVOT Observations
  59. GRB060418: Optical Observations
  60. GRB 060418: Refined Analysis of the Swift-BAT burst
  61. GRB 060418, SMARTS continuing afterglow observations
  62. GRB 060418, SMARTS optical/IR afterglow observations
  63. GRB060418 : LT optical afterglow observation
  64. GRB 060418: REM candidate afterglow
  65. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  66. GRB060413: Swift/UVOT upper limits
  67. GRB 060413: REM NIR Observations
  68. GRB 060413: Refined analysis of the Swift-BAT burst
  69. GRB 060403: MITSuME optical observation
  70. GRB060403: Optical Limit
  71. GRB060403: XRT refined analysis
  72. GRB 060403: Swift/UVOT upper limits
  73. SGR 1900+14: BAT observations
  74. GRB 060403: Refined analysis of the Swift-BAT burst
  75. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  76. GRB 060403: Swift detection of a burst
  77. HETE trigger H4044: RTT150 optical observations
  78. GRB060331: Swift/UVOT upper limits
  79. Swift XRT observations of the HETE transient H4043
  80. H4043, an unusual high-energy transient observed by HETE
  81. GRB 060322: LNA optical limit
  82. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  83. INTEGRAL and XMM ToO observations of SGR1900+14
  84. SGR 1900+14: Swift-BAT detection of a bright outburst
  85. GRB 060323 : WIDGET simultaneous optical observations
  86. GRB 060323: Early optical observation at Xinglong
  87. GRB 060322: Confirmation of Swift XRT afterglow
  88. GRB060323: NOT optical observations
  89. GRB 060322: IAC80 optical observations
  90. GRB 060322: Swift XRT afterglow candidate
  91. GRB060323: P60 Observations
  92. GRB 060323: Swift/UVOT Observations
  93. GRB 060323: optical afterglow confirmed
  94. GRB060323: NOT observations
  95. GRB 060323: Optical Observations
  96. GRB 060323: Refined analysis of the Swift-BAT burst
  97. GRB 060323: optical observations at TNG
  98. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  99. GRB 060322: Refined analysis of the Swift-BAT burst
  100. GRB060323, optical observation

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