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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"

18476 results found.

  1. GRB 060427: NOT observations
  2. GRB 060427: Swift/UVOT upper limits.
  3. GRB 060427: Refined analysis of the Swift-BAT burst
  4. GRB060427: Swift XRT Team refined analysis
  5. GRB060418: Swift XRT Team Further Refined Analysis
  6. GRB 060427, optical observation
  7. GRB 060427: Swift detection of a burst
  8. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  9. GRB 060424: Refined analysis of the Swift-BAT burst
  10. GRB 060424: Swift detection of a burst
  11. Swift-BAT detection of Mrk 421
  12. GRB060421: Swift/UVOT observations
  13. GRB 060421: Swift-BAT Refined Analysis
  14. GRB 060421: Swift-XRT refined analysis
  15. GRB 060418: prediction of t_break
  16. Konus-Wind observation of GRB 060418
  17. GRB(?)060421:MASTER optical limit
  18. GRB(?)060421 : XRT position
  19. Possible GRB060421: BART limits
  20. GRB(?) 060421: Swift detection of a burst
  21. GRB060418: Swift/UVOT Observations
  22. GRB 060418: FRAM early afterglow observation
  23. GRB 060418: Refined Analysis of the Swift-BAT burst
  24. VLT/UVES observations of GRB060418
  25. GRB060418: Swift XRT Team Refined Analysis
  26. GRB060418: Magellan/MIKE Spectroscopic Redshift
  27. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  28. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  29. GRB060413: Swift/UVOT upper limits
  30. SGR 1900+14: Swift detection of an outburst
  31. GRB 060413: Refined analysis of the Swift-BAT burst
  32. GRB 060413: XRT refined analysis
  33. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  34. GRB 060413: Swift detection of a burst
  35. GRB060403: XRT refined analysis
  36. GRB 060403: Swift/UVOT upper limits
  37. SGR 1900+14: BAT observations
  38. GRB 060403: Refined analysis of the Swift-BAT burst
  39. GRB060403: Swift XRT refined position
  40. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  41. GRB 060403: Swift detection of a burst
  42. GRB060331: Swift/UVOT upper limits
  43. Swift XRT observations of the HETE transient H4043
  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 060322: Confirmation of Swift XRT afterglow
  49. GRB060323: optical limit
  50. SGR 1900+14: CORRECTION to GCN 4923
  51. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  52. SGR 1900+14: Swift detection of renewed activity
  53. GRB060323: NOT optical observations
  54. GRB 060322: IAC80 optical observations
  55. GRB 060322: Swift XRT afterglow candidate
  56. GRB 060323: Swift/UVOT Observations
  57. GRB060323: NOT observations
  58. GRB 060323: Refined analysis of the Swift-BAT burst
  59. GRB 060323: Swift XRT refined analysis
  60. GRB 060323: Swift/XRT position
  61. GRB 060322: Refined analysis of the Swift-BAT burst
  62. GRB060323 - SDSS Pre-Burst Observations
  63. GRB 060323: Swift detection of a burst with a possible optical afterglow
  64. GRB 060322: Swift-BAT detection of a 200-sec burst
  65. GRB 060319: IAC-80 optical observations
  66. GRB060319: Swift XRT refined analysis
  67. GRB060319: Swift/UVOT upper limits
  68. GRB 060319: Swift-BAT refined analysis
  69. GRB060319: Swift/XRT position
  70. GRB 060319: Swift detection of a burst
  71. Konus-Wind observation of GRB 060313
  72. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  73. GRB 060313: Swift/UVOT Observations
  74. GRB 060313: Swift-XRT team refined analysis
  75. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  76. GRB 060313: Swift XRT position
  77. GRB060313: optical and near infrared observations with REM
  78. GRB 060313: Swift-BAT detection of a bright short hard burst
  79. GRB060312: Swift UVOT observation
  80. GRB 060312: Refined analysis of the Swift-BAT burst
  81. GRB 060312: Swift XRT team refined analysis
  82. GRB060306: APO Ks-band Imaging Observations
  83. GRB 060312: ROTSE-III Optical Limits
  84. GRB 060312: Swift detection of a burst
  85. Bright short hard GRB 060303: IPN localization and Konus spectrum
  86. GRB060218: analysis of the XMM-Newton observation
  87. Swift/UVOT observations of GRB060306
  88. GRB 060306: Swift-BAT refined analysis
  89. GRB 060306: Swift-XRT team refined analysis
  90. GRB 060306: Swift detection of a bright burst
  91. GRB060218: Ep,i - Eiso correlation
  92. GRB 060223b: Swift/UVOT Upper Limits
  93. GRB 060223B: Swift XRT possible afterglow
  94. GRB 060223B: Swift-BAT refined analysis
  95. GRB 060223a: Swift/UVOT refined analysis
  96. GRB 060223: Swift XRT Team preliminary analysis
  97. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  98. GRB 060223B: Swift detection of a bright burst
  99. GRB 060223: Swift-BAT refined analysis
  100. GRB 060223: Swift/UVOT Confirmation of Optical Afterglow

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