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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"

18480 results found.

  1. GRB 060428A: Refined analysis of the Swift-BAT burst
  2. GRB060428A: Swift XRT Team refined analysis
  3. GRB 060428B: Swift detection of a burst
  4. GRB 060428: Swift detection of a burst
  5. GRB 060427: NOT observations
  6. GRB 060427: Swift/UVOT upper limits.
  7. GRB 060427: Refined analysis of the Swift-BAT burst
  8. GRB060427: Swift XRT Team refined analysis
  9. GRB060418: Swift XRT Team Further Refined Analysis
  10. GRB 060427, optical observation
  11. GRB 060427: Swift detection of a burst
  12. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  13. GRB 060424: Refined analysis of the Swift-BAT burst
  14. GRB 060424: Swift detection of a burst
  15. Swift-BAT detection of Mrk 421
  16. GRB060421: Swift/UVOT observations
  17. GRB 060421: Swift-BAT Refined Analysis
  18. GRB 060421: Swift-XRT refined analysis
  19. GRB 060418: prediction of t_break
  20. Konus-Wind observation of GRB 060418
  21. GRB(?)060421:MASTER optical limit
  22. GRB(?)060421 : XRT position
  23. Possible GRB060421: BART limits
  24. GRB(?) 060421: Swift detection of a burst
  25. GRB060418: Swift/UVOT Observations
  26. GRB 060418: FRAM early afterglow observation
  27. GRB 060418: Refined Analysis of the Swift-BAT burst
  28. VLT/UVES observations of GRB060418
  29. GRB060418: Swift XRT Team Refined Analysis
  30. GRB060418: Magellan/MIKE Spectroscopic Redshift
  31. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  32. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  33. GRB060413: Swift/UVOT upper limits
  34. SGR 1900+14: Swift detection of an outburst
  35. GRB 060413: Refined analysis of the Swift-BAT burst
  36. GRB 060413: XRT refined analysis
  37. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  38. GRB 060413: Swift detection of a burst
  39. GRB060403: XRT refined analysis
  40. GRB 060403: Swift/UVOT upper limits
  41. SGR 1900+14: BAT observations
  42. GRB 060403: Refined analysis of the Swift-BAT burst
  43. GRB060403: Swift XRT refined position
  44. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  45. GRB 060403: Swift detection of a burst
  46. GRB060331: Swift/UVOT upper limits
  47. Swift XRT observations of the HETE transient H4043
  48. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  49. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  50. SGR 1900+14: Swift-BAT detection of a bright outburst
  51. GRB 060323 : WIDGET simultaneous optical observations
  52. GRB 060322: Confirmation of Swift XRT afterglow
  53. GRB060323: optical limit
  54. SGR 1900+14: CORRECTION to GCN 4923
  55. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  56. SGR 1900+14: Swift detection of renewed activity
  57. GRB060323: NOT optical observations
  58. GRB 060322: IAC80 optical observations
  59. GRB 060322: Swift XRT afterglow candidate
  60. GRB 060323: Swift/UVOT Observations
  61. GRB060323: NOT observations
  62. GRB 060323: Refined analysis of the Swift-BAT burst
  63. GRB 060323: Swift XRT refined analysis
  64. GRB 060323: Swift/XRT position
  65. GRB 060322: Refined analysis of the Swift-BAT burst
  66. GRB060323 - SDSS Pre-Burst Observations
  67. GRB 060323: Swift detection of a burst with a possible optical afterglow
  68. GRB 060322: Swift-BAT detection of a 200-sec burst
  69. GRB 060319: IAC-80 optical observations
  70. GRB060319: Swift XRT refined analysis
  71. GRB060319: Swift/UVOT upper limits
  72. GRB 060319: Swift-BAT refined analysis
  73. GRB060319: Swift/XRT position
  74. GRB 060319: Swift detection of a burst
  75. Konus-Wind observation of GRB 060313
  76. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  77. GRB 060313: Swift/UVOT Observations
  78. GRB 060313: Swift-XRT team refined analysis
  79. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  80. GRB 060313: Swift XRT position
  81. GRB060313: optical and near infrared observations with REM
  82. GRB 060313: Swift-BAT detection of a bright short hard burst
  83. GRB060312: Swift UVOT observation
  84. GRB 060312: Refined analysis of the Swift-BAT burst
  85. GRB 060312: Swift XRT team refined analysis
  86. GRB060306: APO Ks-band Imaging Observations
  87. GRB 060312: ROTSE-III Optical Limits
  88. GRB 060312: Swift detection of a burst
  89. Bright short hard GRB 060303: IPN localization and Konus spectrum
  90. GRB060218: analysis of the XMM-Newton observation
  91. Swift/UVOT observations of GRB060306
  92. GRB 060306: Swift-BAT refined analysis
  93. GRB 060306: Swift-XRT team refined analysis
  94. GRB 060306: Swift detection of a bright burst
  95. GRB060218: Ep,i - Eiso correlation
  96. GRB 060223b: Swift/UVOT Upper Limits
  97. GRB 060223B: Swift XRT possible afterglow
  98. GRB 060223B: Swift-BAT refined analysis
  99. GRB 060223a: Swift/UVOT refined analysis
  100. GRB 060223: Swift XRT Team preliminary analysis

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