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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"

18408 results found.

  1. GRB060502B: correction to XRT position
  2. GRB 060502B: MASTER optical observations
  3. GRB 060502B: Swift detection of a short burst
  4. GRB060502: Swift-XRT refined analysis
  5. GRB 060502: Swift-BAT refined analysis
  6. GRB 060502: APO Spectroscopic Observations
  7. GRB060501: Swift UVOT followup observations
  8. GRB060502: Super-LOTIS Observations
  9. GRB 060502: Swift detection of a burst with an optical counterpart
  10. GRB 060501: MDM Observations
  11. GRB060501: Super-LOTIS observations
  12. GRB060501: P60 imaging and afterglow candidate
  13. GRB 060501: Refined analysis of the Swift-BAT burst
  14. GRB060501: Swift XRT position
  15. GRB 060501: ROTSE-III Optical Limits
  16. GRB 060501: Swift detection of a burst
  17. GRB060428B: optical observation
  18. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  19. GRB 060428B: MDM Observations
  20. GRB060428B: Swift XRT Team refined analysis
  21. GRB 060427B: IPN localization of a short hard burst
  22. GRB 060428B: Refined analysis of the Swift-BAT burst
  23. GRB 060428B: KAIT observations
  24. GRB060428A: Swift/UVOT observations.
  25. GRB060428B, optical observation
  26. GRB 060428A: Refined analysis of the Swift-BAT burst
  27. GRB060428A: Swift XRT Team refined analysis
  28. GRB 060428B: Swift detection of a burst
  29. GRB 060428: Swift detection of a burst
  30. GRB 060427: NOT observations
  31. GRB 060427: Swift/UVOT upper limits.
  32. GRB 060427: Refined analysis of the Swift-BAT burst
  33. GRB060427: Swift XRT Team refined analysis
  34. GRB060418: Swift XRT Team Further Refined Analysis
  35. GRB 060427, optical observation
  36. GRB 060427: Swift detection of a burst
  37. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  38. GRB 060424: Refined analysis of the Swift-BAT burst
  39. GRB 060424: Swift detection of a burst
  40. Swift-BAT detection of Mrk 421
  41. GRB060421: Swift/UVOT observations
  42. GRB 060421: Swift-BAT Refined Analysis
  43. GRB 060421: Swift-XRT refined analysis
  44. GRB 060418: prediction of t_break
  45. Konus-Wind observation of GRB 060418
  46. GRB(?)060421:MASTER optical limit
  47. GRB(?)060421 : XRT position
  48. Possible GRB060421: BART limits
  49. GRB(?) 060421: Swift detection of a burst
  50. GRB060418: Swift/UVOT Observations
  51. GRB 060418: FRAM early afterglow observation
  52. GRB 060418: Refined Analysis of the Swift-BAT burst
  53. VLT/UVES observations of GRB060418
  54. GRB060418: Swift XRT Team Refined Analysis
  55. GRB060418: Magellan/MIKE Spectroscopic Redshift
  56. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  57. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  58. GRB060413: Swift/UVOT upper limits
  59. SGR 1900+14: Swift detection of an outburst
  60. GRB 060413: Refined analysis of the Swift-BAT burst
  61. GRB 060413: XRT refined analysis
  62. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  63. GRB 060413: Swift detection of a burst
  64. GRB060403: XRT refined analysis
  65. GRB 060403: Swift/UVOT upper limits
  66. SGR 1900+14: BAT observations
  67. GRB 060403: Refined analysis of the Swift-BAT burst
  68. GRB060403: Swift XRT refined position
  69. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  70. GRB 060403: Swift detection of a burst
  71. GRB060331: Swift/UVOT upper limits
  72. Swift XRT observations of the HETE transient H4043
  73. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  74. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  75. SGR 1900+14: Swift-BAT detection of a bright outburst
  76. GRB 060323 : WIDGET simultaneous optical observations
  77. GRB 060322: Confirmation of Swift XRT afterglow
  78. GRB060323: optical limit
  79. SGR 1900+14: CORRECTION to GCN 4923
  80. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  81. SGR 1900+14: Swift detection of renewed activity
  82. GRB060323: NOT optical observations
  83. GRB 060322: IAC80 optical observations
  84. GRB 060322: Swift XRT afterglow candidate
  85. GRB 060323: Swift/UVOT Observations
  86. GRB060323: NOT observations
  87. GRB 060323: Refined analysis of the Swift-BAT burst
  88. GRB 060323: Swift XRT refined analysis
  89. GRB 060323: Swift/XRT position
  90. GRB 060322: Refined analysis of the Swift-BAT burst
  91. GRB060323 - SDSS Pre-Burst Observations
  92. GRB 060323: Swift detection of a burst with a possible optical afterglow
  93. GRB 060322: Swift-BAT detection of a 200-sec burst
  94. GRB 060319: IAC-80 optical observations
  95. GRB060319: Swift XRT refined analysis
  96. GRB060319: Swift/UVOT upper limits
  97. GRB 060319: Swift-BAT refined analysis
  98. GRB060319: Swift/XRT position
  99. GRB 060319: Swift detection of a burst
  100. Konus-Wind observation of GRB 060313

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