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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"

27416 results found.

  1. GRB 060428B: Swift detection of a burst
  2. GRB 060428: Swift detection of a burst
  3. GRB 060427: Swift/UVOT upper limits.
  4. GRB 060427: Refined analysis of the Swift-BAT burst
  5. GRB060427: Swift XRT Team refined analysis
  6. GRB060418: Swift XRT Team Further Refined Analysis
  7. GRB 060427, optical observation
  8. GRB 060427: Swift detection of a burst
  9. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  10. GRB060424: optical afterglow detection
  11. GRB 060424: Refined analysis of the Swift-BAT burst
  12. GRB 060424: Swift detection of a burst
  13. Swift-BAT detection of Mrk 421
  14. GRB060421: Swift/UVOT observations
  15. GRB 060421: Swift-BAT Refined Analysis
  16. GRB 060421: Swift-XRT refined analysis
  17. Konus-Wind observation of GRB 060418
  18. GRB(?)060421 : XRT position
  19. Possible GRB060421: BART limits
  20. GRB(?) 060421: Swift detection of a burst
  21. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  22. GRB060418: Swift/UVOT Observations
  23. GRB 060418: FRAM early afterglow observation
  24. GRB 060418: Refined Analysis of the Swift-BAT burst
  25. VLT/UVES observations of GRB060418
  26. GRB060418: Swift XRT Team Refined Analysis
  27. GRB060418: Magellan/MIKE Spectroscopic Redshift
  28. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  29. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  30. GRB060413: Swift/UVOT upper limits
  31. SGR 1900+14: Swift detection of an outburst
  32. GRB 060413: Refined analysis of the Swift-BAT burst
  33. GRB 060413: XRT refined analysis
  34. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  35. GRB 060413: Swift detection of a burst
  36. GRB060403: XRT refined analysis
  37. GRB 060403: Swift/UVOT upper limits
  38. SGR 1900+14: BAT observations
  39. GRB 060403: Refined analysis of the Swift-BAT burst
  40. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  41. GRB 060403: Swift detection of a burst
  42. HETE trigger H4044: RTT150 optical observations
  43. HETE Trigger 4043: ROTSE-III Optical Limits
  44. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  45. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  46. SGR 1900+14: Swift-BAT detection of a bright outburst
  47. GRB 060323 : WIDGET simultaneous optical observations
  48. GRB 060323: Early optical observation at Xinglong
  49. SGR 1900+14: CORRECTION to GCN 4923
  50. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  51. SGR 1900+14: Swift detection of renewed activity
  52. GRB 060322: Swift XRT afterglow candidate
  53. GRB 060323: Swift/UVOT Observations
  54. GRB 060323: Optical Observations
  55. GRB 060323: Tautenburg OT candidate retraction
  56. GRB 060323: Refined analysis of the Swift-BAT burst
  57. GRB 060323: Swift XRT refined analysis
  58. GRB 060323: Swift/XRT position
  59. GRB 060322: Refined analysis of the Swift-BAT burst
  60. GRB060323 - SDSS Pre-Burst Observations
  61. GRB 060323: Swift detection of a burst with a possible optical afterglow
  62. GRB 060322: Swift-BAT detection of a 200-sec burst
  63. GRB060319: Swift XRT refined analysis
  64. GRB060319: Swift/UVOT upper limits
  65. GRB 060319: Swift-BAT refined analysis
  66. GRB 060319: Swift detection of a burst
  67. Konus-Wind observation of GRB 060313
  68. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  69. GRB 060313: Swift/UVOT Observations
  70. GRB 060313: Swift-XRT team refined analysis
  71. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  72. GRB 060313: Swift XRT position
  73. GRB060313: optical and near infrared observations with REM
  74. GRB 060313: Swift-BAT detection of a bright short hard burst
  75. GRB060218: SARA Observations of SN2006aj
  76. GRB060312: Swift UVOT observation
  77. GRB 060312: Refined analysis of the Swift-BAT burst
  78. GRB 060312: Swift XRT team refined analysis
  79. GRB060306: APO Ks-band Imaging Observations
  80. GRB 060312: ROTSE-III Optical Limits
  81. GRB 060312: Swift detection of a burst
  82. Bright short hard GRB 060303: IPN localization and Konus spectrum
  83. GRB060219: Liverpool Telescope observations
  84. GRB060218: analysis of the XMM-Newton observation
  85. Swift/UVOT observations of GRB060306
  86. GRB 060306: Swift-BAT refined analysis
  87. GRB 060306: Swift-XRT team refined analysis
  88. GRB 060306: Swift detection of a bright burst
  89. GRB060218: Ep,i - Eiso correlation
  90. GRB060223b: optical limit
  91. GRB 060223b: Swift/UVOT Upper Limits
  92. GRB 060223B: Swift XRT possible afterglow
  93. GRB 060204B: GETS early limit
  94. GRB 060223A:Xinglong optical limits
  95. GRB 060223B: ART optical limits
  96. GRB 060223B: Swift-BAT refined analysis
  97. GRB 060223a: Swift/UVOT refined analysis
  98. GRB 060223: Swift XRT Team preliminary analysis
  99. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  100. GRB 060223B: Swift detection of a bright burst

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