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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18349 results found.

  1. SGR 1900+14: Swift detection of an outburst
  2. GRB 060413: Refined analysis of the Swift-BAT burst
  3. GRB 060413: XRT refined analysis
  4. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  5. GRB 060413: Swift detection of a burst
  6. GRB060403: XRT refined analysis
  7. GRB 060403: Swift/UVOT upper limits
  8. SGR 1900+14: BAT observations
  9. GRB 060403: Refined analysis of the Swift-BAT burst
  10. GRB060403: Swift XRT refined position
  11. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  12. GRB 060403: Swift detection of a burst
  13. GRB060331: Swift/UVOT upper limits
  14. Swift XRT observations of the HETE transient H4043
  15. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  16. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  17. SGR 1900+14: Swift-BAT detection of a bright outburst
  18. GRB 060323 : WIDGET simultaneous optical observations
  19. GRB 060322: Confirmation of Swift XRT afterglow
  20. GRB060323: optical limit
  21. SGR 1900+14: CORRECTION to GCN 4923
  22. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  23. SGR 1900+14: Swift detection of renewed activity
  24. GRB060323: NOT optical observations
  25. GRB 060322: IAC80 optical observations
  26. GRB 060322: Swift XRT afterglow candidate
  27. GRB 060323: Swift/UVOT Observations
  28. GRB060323: NOT observations
  29. GRB 060323: Refined analysis of the Swift-BAT burst
  30. GRB 060323: Swift XRT refined analysis
  31. GRB 060323: Swift/XRT position
  32. GRB 060322: Refined analysis of the Swift-BAT burst
  33. GRB060323 - SDSS Pre-Burst Observations
  34. GRB 060323: Swift detection of a burst with a possible optical afterglow
  35. GRB 060322: Swift-BAT detection of a 200-sec burst
  36. GRB 060319: IAC-80 optical observations
  37. GRB060319: Swift XRT refined analysis
  38. GRB060319: Swift/UVOT upper limits
  39. GRB 060319: Swift-BAT refined analysis
  40. GRB060319: Swift/XRT position
  41. GRB 060319: Swift detection of a burst
  42. Konus-Wind observation of GRB 060313
  43. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  44. GRB 060313: Swift/UVOT Observations
  45. GRB 060313: Swift-XRT team refined analysis
  46. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  47. GRB 060313: Swift XRT position
  48. GRB060313: optical and near infrared observations with REM
  49. GRB 060313: Swift-BAT detection of a bright short hard burst
  50. GRB060312: Swift UVOT observation
  51. GRB 060312: Refined analysis of the Swift-BAT burst
  52. GRB 060312: Swift XRT team refined analysis
  53. GRB060306: APO Ks-band Imaging Observations
  54. GRB 060312: ROTSE-III Optical Limits
  55. GRB 060312: Swift detection of a burst
  56. Bright short hard GRB 060303: IPN localization and Konus spectrum
  57. GRB060218: analysis of the XMM-Newton observation
  58. Swift/UVOT observations of GRB060306
  59. GRB 060306: Swift-BAT refined analysis
  60. GRB 060306: Swift-XRT team refined analysis
  61. GRB 060306: Swift detection of a bright burst
  62. GRB060218: Ep,i - Eiso correlation
  63. GRB 060223b: Swift/UVOT Upper Limits
  64. GRB 060223B: Swift XRT possible afterglow
  65. GRB 060223B: Swift-BAT refined analysis
  66. GRB 060223a: Swift/UVOT refined analysis
  67. GRB 060223: Swift XRT Team preliminary analysis
  68. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  69. GRB 060223B: Swift detection of a bright burst
  70. GRB 060223: Swift-BAT refined analysis
  71. GRB 060223: Swift/UVOT Confirmation of Optical Afterglow
  72. GRB 060223: Swift detection of a burst
  73. GRB 060219: Swift-BAT refined analysis
  74. GRB 060218: Further refined analysis of the Swift-BAT burst
  75. GRB 060218: Likely an underluminous GRB
  76. GRB 060219: SDSS galaxy inside XRT error circle
  77. GRB060218: UV Detection and Light Curves
  78. GRB 060219: Swift/UVOT Upper Limits
  79. GRB 060219: Swift-XRT Team refined analysis
  80. GRB 051221B: Swift-XRT Team Refined Analysis
  81. GRB 060219: Partial refined analysis of the Swift-BAT burst
  82. GRB 060219: Swift-XRT position typo correction
  83. GRB 060219: Swift-XRT position
  84. GRB 060218: optical/nIR observations at La Palma
  85. GRB 060219: Swift-BAT detection of a weak burst
  86. Oddball GRB 060218, transient or GRB?
  87. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  88. Brightening of the Optical Counterpart of the Possible GRB 060218
  89. GRB 060218: MDM Observations
  90. GRB 060218A: ROTSE-III Possible Optical Flare
  91. GRB060218: Swift/XRT refined position of a possible burst
  92. Preliminary refined analysis of the Swift-BAT trigger 191157
  93. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  94. GRB 060211B: Swift/UVOT Upper Limits
  95. GRB 060218: Swift XRT Position
  96. GRB 060218: Swift-BAT detection of a possible burst
  97. GRB 060213: optical afterglow not confirmed
  98. Swift UVOT observations of GRB060213
  99. GRB060213: Swift XRT observations and possible afterglow candidate
  100. GRB 060211b: WIRO NIR Observations

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