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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"

28048 results found.

  1. GRB 060421: TTT Observations
  2. GRB060421: Swift/UVOT observations
  3. GRB 060421: Swift-BAT Refined Analysis
  4. GRB 060421: Swift-XRT refined analysis
  5. GRB 060418: prediction of t_break
  6. GRB(?) 060421: Swift detection of a burst
  7. Erratum of GCN 4983 for GRB 060418 IR follow-up
  8. GRB 060418 : IR afterglow observations
  9. GRB 060418: Radio Observations
  10. GRB060418, BVRcIc field calibration
  11. GRB060418: Swift/UVOT Observations
  12. GRB060418: Optical Observations
  13. GRB 060418: Refined Analysis of the Swift-BAT burst
  14. GRB 060418, SMARTS continuing afterglow observations
  15. GRB 060418, SMARTS optical/IR afterglow observations
  16. GRB060418 : LT optical afterglow observation
  17. GRB 060418: REM candidate afterglow
  18. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  19. GRB060413: Swift/UVOT upper limits
  20. GRB 060413: REM NIR Observations
  21. GRB 060413: Refined analysis of the Swift-BAT burst
  22. GRB 060403: MITSuME optical observation
  23. GRB060403: Optical Limit
  24. GRB060403: XRT refined analysis
  25. GRB 060403: Swift/UVOT upper limits
  26. SGR 1900+14: BAT observations
  27. GRB 060403: Refined analysis of the Swift-BAT burst
  28. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  29. GRB 060403: Swift detection of a burst
  30. HETE trigger H4044: RTT150 optical observations
  31. GRB060331: Swift/UVOT upper limits
  32. Swift XRT observations of the HETE transient H4043
  33. H4043, an unusual high-energy transient observed by HETE
  34. GRB 060322: LNA optical limit
  35. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  36. INTEGRAL and XMM ToO observations of SGR1900+14
  37. SGR 1900+14: Swift-BAT detection of a bright outburst
  38. GRB 060323 : WIDGET simultaneous optical observations
  39. GRB 060323: Early optical observation at Xinglong
  40. GRB 060322: Confirmation of Swift XRT afterglow
  41. GRB060323: NOT optical observations
  42. GRB 060322: IAC80 optical observations
  43. GRB 060322: Swift XRT afterglow candidate
  44. GRB060323: P60 Observations
  45. GRB 060323: Swift/UVOT Observations
  46. GRB 060323: optical afterglow confirmed
  47. GRB060323: NOT observations
  48. GRB 060323: Optical Observations
  49. GRB 060323: Refined analysis of the Swift-BAT burst
  50. GRB 060323: optical observations at TNG
  51. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  52. GRB 060322: Refined analysis of the Swift-BAT burst
  53. GRB060323, optical observation
  54. GRB060323 - SDSS Pre-Burst Observations
  55. GRB 060323: Swift detection of a burst with a possible optical afterglow
  56. GRB 060322: Swift-BAT detection of a 200-sec burst
  57. GRB 060218/SN 2006aj, LNA optical observation
  58. GRB060218: Refined photometric calibration of comparison stars
  59. GRB 060319: WHT K-band candidate afterglow
  60. GRB060319: Swift/UVOT upper limits
  61. GRB 060319: Swift-BAT refined analysis
  62. GRB 060319 optical observations at TNG
  63. GRB060319 : Liverpool Telescope optical limit
  64. GRB060319 - SDSS Pre-burst Observations
  65. GRB060313: Radio Observations
  66. GRB 060313: early afterglow NIR upper limits with REM
  67. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  68. GRB 060313: Swift/UVOT Observations
  69. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  70. GRB 060313, SMARTS optical counterpart?
  71. GRB 060313, SMARTS optical/IR observations
  72. GRB060313: optical and near infrared observations with REM
  73. GRB060218: SARA Observations of SN2006aj
  74. GRB 060312: Refined analysis of the Swift-BAT burst
  75. GRB 060218/SN 2006aj, high resolution spectra
  76. GRB 060312: Swift XRT team refined analysis
  77. GRB060306: APO Ks-band Imaging Observations
  78. GRB 060312: ROTSE-III Optical Limits
  79. Bright short hard GRB 060303: IPN localization and Konus spectrum
  80. GRB060219: Liverpool Telescope observations
  81. GRB 060306: MAGNUM observations
  82. GRB060218: analysis of the XMM-Newton observation
  83. Swift/UVOT observations of GRB060306
  84. GRB 060306: Swift-BAT refined analysis
  85. GRB 060306: Swift-XRT team refined analysis
  86. GRB 060306: Swift detection of a bright burst
  87. GRB060218: Ep,i - Eiso correlation
  88. GRB060223b: optical limit
  89. GRB 060223b: Swift/UVOT Upper Limits
  90. GRB 060218/SN 2006aj: K-380 optical observations
  91. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  92. GRB 060223B: Swift XRT possible afterglow
  93. GRB 060218/SN 2006aj: ABT observations
  94. GRB 060218/SN 2006aj: REM optical and near-infrared observations
  95. GRB 060218 : Radio upper limits from GMRT
  96. GRB 060218/SN 2006aj: RBO optical observations
  97. GRB 060204B: GETS early limit
  98. GRB 060223A:Xinglong optical limits
  99. GRB 060223B: Swift-BAT refined analysis
  100. GRB 060223a: Swift/UVOT refined analysis

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