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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"

19090 results found.

  1. GRB 060502B: AROMA refined photometric calibration
  2. GRB 060502B MDM Follow-up Observation
  3. GRB 060502b: Gemini imaging and spectroscopy
  4. GRB060502A, optical observation
  5. GRB 060502B: Swift/UVOT upper limits
  6. GRB 060502A: Swift/UVOT source detection
  7. GRB 060502B: Refined analysis of the Swift-BAT short burst
  8. GRB 060427B Milagro GeV/TeV Observations
  9. GRB 060501: P60 Observations and Candidate Retraction
  10. GRB 060502B: Xinglong optical observation
  11. GRB060501: Swift UVOT followup observations
  12. GRB 060502: P60 Afterglow Confirmation
  13. GRB 060502: Swift detection of a burst with an optical counterpart
  14. GRB060501: Super-LOTIS observations
  15. GRB060501: P60 imaging and afterglow candidate
  16. GRB060428B - SDSS Pre-Burst Observations
  17. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  18. GRB 060427B: IPN localization of a short hard burst
  19. GRB 060428B: Xinglong I-band limit
  20. GRB 051117A: Bright host galaxy not confirmed
  21. GRB060428A: Swift/UVOT observations.
  22. GRB060428B, optical observation
  23. GRB 060428A: Refined analysis of the Swift-BAT burst
  24. GRB 060428b : Kiso R-band limit
  25. GRB 060428b: Optical afterglow candidate
  26. GRB 060428B: Swift detection of a burst
  27. GRB 060427: NIR observations
  28. GRB060427: Xinglong optical Observations
  29. GRB 060428: Swift detection of a burst
  30. GRB 060427: Swift/UVOT upper limits.
  31. GRB 060427, optical observation
  32. GRB 060427: Swift detection of a burst
  33. GRB 060424: Refined analysis of the Swift-BAT burst
  34. GRB060421: Swift/UVOT observations
  35. GRB(?) 060421: Swift detection of a burst
  36. Erratum of GCN 4983 for GRB 060418 IR follow-up
  37. GRB 060418 : IR afterglow observations
  38. GRB 060418: Radio Observations
  39. GRB060418, BVRcIc field calibration
  40. GRB060418: Swift/UVOT Observations
  41. GRB 060418: Refined Analysis of the Swift-BAT burst
  42. GRB060418 : LT optical afterglow observation
  43. GRB 060418: REM candidate afterglow
  44. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  45. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  46. GRB060413: Swift/UVOT upper limits
  47. GRB 060413: REM NIR Observations
  48. SGR 1900+14: Swift detection of an outburst
  49. GRB 060413: Swift detection of a burst
  50. GRB 060403: MITSuME optical observation
  51. GRB060403: Optical Limit
  52. GRB 060403: Swift/UVOT upper limits
  53. SGR 1900+14: BAT observations
  54. GRB 060403: Refined analysis of the Swift-BAT burst
  55. GRB 060403: Swift detection of a burst
  56. HETE trigger H4044: RTT150 optical observations
  57. GRB060331: Swift/UVOT upper limits
  58. Swift XRT observations of the HETE transient H4043
  59. H4043, an unusual high-energy transient observed by HETE
  60. GRB 060322: LNA optical limit
  61. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  62. GRB 060323 : WIDGET simultaneous optical observations
  63. GRB 060323: Early optical observation at Xinglong
  64. GRB 060322: Confirmation of Swift XRT afterglow
  65. GRB060323: NOT optical observations
  66. GRB 060322: IAC80 optical observations
  67. GRB 060322: Swift XRT afterglow candidate
  68. GRB060323: P60 Observations
  69. GRB 060323: Swift/UVOT Observations
  70. GRB 060323: optical afterglow confirmed
  71. GRB060323: NOT observations
  72. GRB 060323: Optical Observations
  73. GRB 060323: optical observations at TNG
  74. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  75. GRB060323, optical observation
  76. GRB060323 - SDSS Pre-Burst Observations
  77. GRB 060323: Swift detection of a burst with a possible optical afterglow
  78. GRB 060322: Swift-BAT detection of a 200-sec burst
  79. GRB 060218/SN 2006aj, LNA optical observation
  80. GRB060218: Refined photometric calibration of comparison stars
  81. GRB 060319: WHT K-band candidate afterglow
  82. GRB060319: Swift/UVOT upper limits
  83. GRB060319: MASTER limit
  84. GRB 060319 optical observations at TNG
  85. GRB060319 : Liverpool Telescope optical limit
  86. GRB060319 - SDSS Pre-burst Observations
  87. GRB 060319: Swift detection of a burst
  88. GRB060313: Radio Observations
  89. GRB 060313: early afterglow NIR upper limits with REM
  90. GRB 060313: Swift/UVOT Observations
  91. GRB 060313: Swift XRT position
  92. GRB 060313, SMARTS optical/IR observations
  93. GRB060313: optical and near infrared observations with REM
  94. GRB 060313: Swift-BAT detection of a bright short hard burst
  95. GRB060218: SARA Observations of SN2006aj
  96. GRB 060312: Swift XRT team refined analysis
  97. GRB060306: APO Ks-band Imaging Observations
  98. GRB 060312: ROTSE-III Optical Limits
  99. Bright short hard GRB 060303: IPN localization and Konus spectrum
  100. GRB 060306: MAGNUM observations

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