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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"

18732 results found.

  1. GRB060501: Swift UVOT followup observations
  2. GRB060502: Super-LOTIS Observations
  3. GRB 060502: Swift detection of a burst with an optical counterpart
  4. GRB 060501: MDM Observations
  5. GRB060501: Super-LOTIS observations
  6. GRB060501: P60 imaging and afterglow candidate
  7. GRB 060501: Refined analysis of the Swift-BAT burst
  8. GRB060501: Swift XRT position
  9. GRB 060501: ROTSE-III Optical Limits
  10. GRB 060501: Swift detection of a burst
  11. GRB060428B: optical observation
  12. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  13. GRB 060428B: MDM Observations
  14. GRB060428B: Swift XRT Team refined analysis
  15. GRB 060427B: IPN localization of a short hard burst
  16. GRB 060428B: Refined analysis of the Swift-BAT burst
  17. GRB 060428B: KAIT observations
  18. GRB060428A: Swift/UVOT observations.
  19. GRB060428B, optical observation
  20. GRB 060428A: Refined analysis of the Swift-BAT burst
  21. GRB060428A: Swift XRT Team refined analysis
  22. GRB 060428B: Swift detection of a burst
  23. GRB 060428: Swift detection of a burst
  24. GRB 060427: NOT observations
  25. GRB 060427: Swift/UVOT upper limits.
  26. GRB 060427: Refined analysis of the Swift-BAT burst
  27. GRB060427: Swift XRT Team refined analysis
  28. GRB060418: Swift XRT Team Further Refined Analysis
  29. GRB 060427, optical observation
  30. GRB 060427: Swift detection of a burst
  31. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  32. GRB 060424: Refined analysis of the Swift-BAT burst
  33. GRB 060424: Swift detection of a burst
  34. Swift-BAT detection of Mrk 421
  35. GRB060421: Swift/UVOT observations
  36. GRB 060421: Swift-BAT Refined Analysis
  37. GRB 060421: Swift-XRT refined analysis
  38. GRB 060418: prediction of t_break
  39. Konus-Wind observation of GRB 060418
  40. GRB(?)060421:MASTER optical limit
  41. GRB(?)060421 : XRT position
  42. Possible GRB060421: BART limits
  43. GRB(?) 060421: Swift detection of a burst
  44. GRB060418: Swift/UVOT Observations
  45. GRB 060418: FRAM early afterglow observation
  46. GRB 060418: Refined Analysis of the Swift-BAT burst
  47. VLT/UVES observations of GRB060418
  48. GRB060418: Swift XRT Team Refined Analysis
  49. GRB060418: Magellan/MIKE Spectroscopic Redshift
  50. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  51. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  52. GRB060413: Swift/UVOT upper limits
  53. SGR 1900+14: Swift detection of an outburst
  54. GRB 060413: Refined analysis of the Swift-BAT burst
  55. GRB 060413: XRT refined analysis
  56. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  57. GRB 060413: Swift detection of a burst
  58. GRB060403: XRT refined analysis
  59. GRB 060403: Swift/UVOT upper limits
  60. SGR 1900+14: BAT observations
  61. GRB 060403: Refined analysis of the Swift-BAT burst
  62. GRB060403: Swift XRT refined position
  63. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  64. GRB 060403: Swift detection of a burst
  65. GRB060331: Swift/UVOT upper limits
  66. Swift XRT observations of the HETE transient H4043
  67. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  68. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  69. SGR 1900+14: Swift-BAT detection of a bright outburst
  70. GRB 060323 : WIDGET simultaneous optical observations
  71. GRB 060322: Confirmation of Swift XRT afterglow
  72. GRB060323: optical limit
  73. SGR 1900+14: CORRECTION to GCN 4923
  74. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  75. SGR 1900+14: Swift detection of renewed activity
  76. GRB060323: NOT optical observations
  77. GRB 060322: IAC80 optical observations
  78. GRB 060322: Swift XRT afterglow candidate
  79. GRB 060323: Swift/UVOT Observations
  80. GRB060323: NOT observations
  81. GRB 060323: Refined analysis of the Swift-BAT burst
  82. GRB 060323: Swift XRT refined analysis
  83. GRB 060323: Swift/XRT position
  84. GRB 060322: Refined analysis of the Swift-BAT burst
  85. GRB060323 - SDSS Pre-Burst Observations
  86. GRB 060323: Swift detection of a burst with a possible optical afterglow
  87. GRB 060322: Swift-BAT detection of a 200-sec burst
  88. GRB 060319: IAC-80 optical observations
  89. GRB060319: Swift XRT refined analysis
  90. GRB060319: Swift/UVOT upper limits
  91. GRB 060319: Swift-BAT refined analysis
  92. GRB060319: Swift/XRT position
  93. GRB 060319: Swift detection of a burst
  94. Konus-Wind observation of GRB 060313
  95. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  96. GRB 060313: Swift/UVOT Observations
  97. GRB 060313: Swift-XRT team refined analysis
  98. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  99. GRB 060313: Swift XRT position
  100. GRB060313: optical and near infrared observations with REM

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