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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"

18493 results found.

  1. GRB 060501: Refined analysis of the Swift-BAT burst
  2. GRB060501: Swift XRT position
  3. GRB 060501: ROTSE-III Optical Limits
  4. GRB 060501: Swift detection of a burst
  5. GRB060428B: optical observation
  6. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  7. GRB 060428B: MDM Observations
  8. GRB060428B: Swift XRT Team refined analysis
  9. GRB 060427B: IPN localization of a short hard burst
  10. GRB 060428B: Refined analysis of the Swift-BAT burst
  11. GRB 060428B: KAIT observations
  12. GRB060428A: Swift/UVOT observations.
  13. GRB060428B, optical observation
  14. GRB 060428A: Refined analysis of the Swift-BAT burst
  15. GRB060428A: Swift XRT Team refined analysis
  16. GRB 060428B: Swift detection of a burst
  17. GRB 060428: Swift detection of a burst
  18. GRB 060427: NOT observations
  19. GRB 060427: Swift/UVOT upper limits.
  20. GRB 060427: Refined analysis of the Swift-BAT burst
  21. GRB060427: Swift XRT Team refined analysis
  22. GRB060418: Swift XRT Team Further Refined Analysis
  23. GRB 060427, optical observation
  24. GRB 060427: Swift detection of a burst
  25. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  26. GRB 060424: Refined analysis of the Swift-BAT burst
  27. GRB 060424: Swift detection of a burst
  28. Swift-BAT detection of Mrk 421
  29. GRB060421: Swift/UVOT observations
  30. GRB 060421: Swift-BAT Refined Analysis
  31. GRB 060421: Swift-XRT refined analysis
  32. GRB 060418: prediction of t_break
  33. Konus-Wind observation of GRB 060418
  34. GRB(?)060421:MASTER optical limit
  35. GRB(?)060421 : XRT position
  36. Possible GRB060421: BART limits
  37. GRB(?) 060421: Swift detection of a burst
  38. GRB060418: Swift/UVOT Observations
  39. GRB 060418: FRAM early afterglow observation
  40. GRB 060418: Refined Analysis of the Swift-BAT burst
  41. VLT/UVES observations of GRB060418
  42. GRB060418: Swift XRT Team Refined Analysis
  43. GRB060418: Magellan/MIKE Spectroscopic Redshift
  44. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  45. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  46. GRB060413: Swift/UVOT upper limits
  47. SGR 1900+14: Swift detection of an outburst
  48. GRB 060413: Refined analysis of the Swift-BAT burst
  49. GRB 060413: XRT refined analysis
  50. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  51. GRB 060413: Swift detection of a burst
  52. GRB060403: XRT refined analysis
  53. GRB 060403: Swift/UVOT upper limits
  54. SGR 1900+14: BAT observations
  55. GRB 060403: Refined analysis of the Swift-BAT burst
  56. GRB060403: Swift XRT refined position
  57. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  58. GRB 060403: Swift detection of a burst
  59. GRB060331: Swift/UVOT upper limits
  60. Swift XRT observations of the HETE transient H4043
  61. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  62. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  63. SGR 1900+14: Swift-BAT detection of a bright outburst
  64. GRB 060323 : WIDGET simultaneous optical observations
  65. GRB 060322: Confirmation of Swift XRT afterglow
  66. GRB060323: optical limit
  67. SGR 1900+14: CORRECTION to GCN 4923
  68. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  69. SGR 1900+14: Swift detection of renewed activity
  70. GRB060323: NOT optical observations
  71. GRB 060322: IAC80 optical observations
  72. GRB 060322: Swift XRT afterglow candidate
  73. GRB 060323: Swift/UVOT Observations
  74. GRB060323: NOT observations
  75. GRB 060323: Refined analysis of the Swift-BAT burst
  76. GRB 060323: Swift XRT refined analysis
  77. GRB 060323: Swift/XRT position
  78. GRB 060322: Refined analysis of the Swift-BAT burst
  79. GRB060323 - SDSS Pre-Burst Observations
  80. GRB 060323: Swift detection of a burst with a possible optical afterglow
  81. GRB 060322: Swift-BAT detection of a 200-sec burst
  82. GRB 060319: IAC-80 optical observations
  83. GRB060319: Swift XRT refined analysis
  84. GRB060319: Swift/UVOT upper limits
  85. GRB 060319: Swift-BAT refined analysis
  86. GRB060319: Swift/XRT position
  87. GRB 060319: Swift detection of a burst
  88. Konus-Wind observation of GRB 060313
  89. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  90. GRB 060313: Swift/UVOT Observations
  91. GRB 060313: Swift-XRT team refined analysis
  92. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  93. GRB 060313: Swift XRT position
  94. GRB060313: optical and near infrared observations with REM
  95. GRB 060313: Swift-BAT detection of a bright short hard burst
  96. GRB060312: Swift UVOT observation
  97. GRB 060312: Refined analysis of the Swift-BAT burst
  98. GRB 060312: Swift XRT team refined analysis
  99. GRB060306: APO Ks-band Imaging Observations
  100. GRB 060312: ROTSE-III Optical Limits

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