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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"

19604 results found.

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

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