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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"

20356 results found.

  1. GRB 060502B MDM Follow-up Observation
  2. GRB 060502b: Gemini imaging and spectroscopy
  3. GRB060502A, optical observation
  4. GRB 060502B: Swift/UVOT upper limits
  5. GRB 060502A: Swift/UVOT source detection
  6. GRB 060429: Refined IPN error box and Konus-Wind spectrum
  7. GRB 060502B: Refined analysis of the Swift-BAT short burst
  8. GRB060502B: Swift XRT Team refined analysis
  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: P60 imaging and afterglow candidate
  15. GRB 060501: Refined analysis of the Swift-BAT burst
  16. GRB060428B - SDSS Pre-Burst Observations
  17. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  18. GRB 060428A: PROMPT Observations
  19. GRB060428B: Swift XRT Team refined analysis
  20. GRB 060427B: IPN localization of a short hard burst
  21. GRB 060428B: Xinglong I-band limit
  22. GRB 051117A: Bright host galaxy not confirmed
  23. GRB060428A: Swift/UVOT observations.
  24. GRB060428B, optical observation
  25. GRB 060428b : Kiso R-band limit
  26. GRB 060428b: Optical afterglow candidate
  27. GRB 060428B: Swift detection of a burst
  28. GRB 060427: NIR observations
  29. GRB060427: Xinglong optical Observations
  30. GRB 060428: Swift detection of a burst
  31. GRB 060427: Swift/UVOT upper limits.
  32. GRB060427: Swift XRT Team refined analysis
  33. GRB060418: Swift XRT Team Further Refined Analysis
  34. GRB 060427, optical observation
  35. GRB 060427: Swift detection of a burst
  36. GRB 060424: Refined analysis of the Swift-BAT burst
  37. GRB060421: Swift/UVOT observations
  38. GRB(?) 060421: Swift detection of a burst
  39. GRB 060418: Radio Observations
  40. GRB060418, BVRcIc field calibration
  41. GRB060418: Swift/UVOT Observations
  42. GRB060418: Swift XRT Team Refined Analysis
  43. GRB060418 : LT optical afterglow observation
  44. GRB 060418: REM candidate afterglow
  45. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  46. GRB060413: Swift/UVOT upper limits
  47. GRB 060413: REM NIR Observations
  48. GRB 060413: Watcher UBVR observations
  49. GRB 060413: XRT refined analysis
  50. GRB 060403: MITSuME optical observation
  51. GRB060403: Optical Limit
  52. GRB060403: XRT refined analysis
  53. GRB 060403: Swift/UVOT upper limits
  54. SGR 1900+14: BAT observations
  55. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  56. GRB 060403: Swift detection of a burst
  57. HETE trigger H4044: RTT150 optical observations
  58. GRB060331: Swift/UVOT upper limits
  59. Swift XRT observations of the HETE transient H4043
  60. H4043, an unusual high-energy transient observed by HETE
  61. GRB 060322: LNA optical limit
  62. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  63. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  64. GRB 060323 : WIDGET simultaneous optical observations
  65. GRB 060323: Early optical observation at Xinglong
  66. GRB 060322: Confirmation of Swift XRT afterglow
  67. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  68. GRB060323: NOT optical observations
  69. GRB 060322: IAC80 optical observations
  70. GRB 060322: Swift XRT afterglow candidate
  71. GRB060323: P60 Observations
  72. GRB 060323: Swift/UVOT Observations
  73. GRB 060323: optical afterglow confirmed
  74. GRB060323: NOT observations
  75. GRB 060323: Optical Observations
  76. GRB 060323: optical observations at TNG
  77. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  78. GRB060323, optical observation
  79. GRB060323 - SDSS Pre-Burst Observations
  80. GRB 060323: Swift detection of a burst with a possible optical afterglow
  81. GRB 060218/SN 2006aj, LNA optical observation
  82. GRB060218: Refined photometric calibration of comparison stars
  83. GRB 060319: WHT K-band candidate afterglow
  84. GRB060319: Swift/UVOT upper limits
  85. GRB 060319: Swift-BAT refined analysis
  86. GRB 060319 optical observations at TNG
  87. GRB060319 : Liverpool Telescope optical limit
  88. GRB060319 - SDSS Pre-burst Observations
  89. GRB 060319: Swift detection of a burst
  90. GRB060313: Radio Observations
  91. GRB 060313: early afterglow NIR upper limits with REM
  92. GRB 060313: Swift/UVOT Observations
  93. GRB 060313: Swift-XRT team refined analysis
  94. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  95. GRB 060313, SMARTS optical counterpart?
  96. GRB 060313, SMARTS optical/IR observations
  97. GRB060313: optical and near infrared observations with REM
  98. GRB060218: SARA Observations of SN2006aj
  99. GRB 060218/SN 2006aj, high resolution spectra
  100. GRB 060312: Swift XRT team refined analysis

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