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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"

19603 results found.

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

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