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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"

19597 results found.

  1. GRB 060502: Swift detection of a burst with an optical counterpart
  2. GRB 060501: MDM Observations
  3. GRB060501: Super-LOTIS observations
  4. GRB060501: P60 imaging and afterglow candidate
  5. GRB 060501: Refined analysis of the Swift-BAT burst
  6. GRB060501: Swift XRT position
  7. GRB 060501: ROTSE-III Optical Limits
  8. GRB 060501: Swift detection of a burst
  9. GRB060428B: optical observation
  10. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  11. GRB 060428B: MDM Observations
  12. GRB060428B: Swift XRT Team refined analysis
  13. GRB 060427B: IPN localization of a short hard burst
  14. GRB 060428B: Refined analysis of the Swift-BAT burst
  15. GRB 060428B: KAIT observations
  16. GRB060428A: Swift/UVOT observations.
  17. GRB060428B, optical observation
  18. GRB 060428A: Refined analysis of the Swift-BAT burst
  19. GRB060428A: Swift XRT Team refined analysis
  20. GRB 060428B: Swift detection of a burst
  21. GRB 060428: Swift detection of a burst
  22. GRB 060427: NOT observations
  23. GRB 060427: Swift/UVOT upper limits.
  24. GRB 060427: Refined analysis of the Swift-BAT burst
  25. GRB060427: Swift XRT Team refined analysis
  26. GRB060418: Swift XRT Team Further Refined Analysis
  27. GRB 060427, optical observation
  28. GRB 060427: Swift detection of a burst
  29. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  30. GRB 060424: Refined analysis of the Swift-BAT burst
  31. GRB 060424: Swift detection of a burst
  32. Swift-BAT detection of Mrk 421
  33. GRB060421: Swift/UVOT observations
  34. GRB 060421: Swift-BAT Refined Analysis
  35. GRB 060421: Swift-XRT refined analysis
  36. GRB 060418: prediction of t_break
  37. Konus-Wind observation of GRB 060418
  38. GRB(?)060421:MASTER optical limit
  39. GRB(?)060421 : XRT position
  40. Possible GRB060421: BART limits
  41. GRB(?) 060421: Swift detection of a burst
  42. GRB060418: Swift/UVOT Observations
  43. GRB 060418: FRAM early afterglow observation
  44. GRB 060418: Refined Analysis of the Swift-BAT burst
  45. VLT/UVES observations of GRB060418
  46. GRB060418: Swift XRT Team Refined Analysis
  47. GRB060418: Magellan/MIKE Spectroscopic Redshift
  48. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  49. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  50. GRB060413: Swift/UVOT upper limits
  51. SGR 1900+14: Swift detection of an outburst
  52. GRB 060413: Refined analysis of the Swift-BAT burst
  53. GRB 060413: XRT refined analysis
  54. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  55. GRB 060413: Swift detection of a burst
  56. GRB060403: XRT refined analysis
  57. GRB 060403: Swift/UVOT upper limits
  58. SGR 1900+14: BAT observations
  59. GRB 060403: Refined analysis of the Swift-BAT burst
  60. GRB060403: Swift XRT refined position
  61. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  62. GRB 060403: Swift detection of a burst
  63. GRB060331: Swift/UVOT upper limits
  64. Swift XRT observations of the HETE transient H4043
  65. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  66. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  67. SGR 1900+14: Swift-BAT detection of a bright outburst
  68. GRB 060323 : WIDGET simultaneous optical observations
  69. GRB 060322: Confirmation of Swift XRT afterglow
  70. GRB060323: optical limit
  71. SGR 1900+14: CORRECTION to GCN 4923
  72. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  73. SGR 1900+14: Swift detection of renewed activity
  74. GRB060323: NOT optical observations
  75. GRB 060322: IAC80 optical observations
  76. GRB 060322: Swift XRT afterglow candidate
  77. GRB 060323: Swift/UVOT Observations
  78. GRB060323: NOT observations
  79. GRB 060323: Refined analysis of the Swift-BAT burst
  80. GRB 060323: Swift XRT refined analysis
  81. GRB 060323: Swift/XRT position
  82. GRB 060322: Refined analysis of the Swift-BAT burst
  83. GRB060323 - SDSS Pre-Burst Observations
  84. GRB 060323: Swift detection of a burst with a possible optical afterglow
  85. GRB 060322: Swift-BAT detection of a 200-sec burst
  86. GRB 060319: IAC-80 optical observations
  87. GRB060319: Swift XRT refined analysis
  88. GRB060319: Swift/UVOT upper limits
  89. GRB 060319: Swift-BAT refined analysis
  90. GRB060319: Swift/XRT position
  91. GRB 060319: Swift detection of a burst
  92. Konus-Wind observation of GRB 060313
  93. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  94. GRB 060313: Swift/UVOT Observations
  95. GRB 060313: Swift-XRT team refined analysis
  96. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  97. GRB 060313: Swift XRT position
  98. GRB060313: optical and near infrared observations with REM
  99. GRB 060313: Swift-BAT detection of a bright short hard burst
  100. GRB060312: Swift UVOT observation

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