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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"

18635 results found.

  1. GRB070802: Swift/UVOT upper limits
  2. GRB 070802, Swift-BAT refined analysis
  3. GRB 070802: refined Swift XRT position
  4. GRB 070802: GROND J band candidate
  5. GRB 070802: Swift detection of a burst
  6. GRB 070731, Swift-BAT refined analysis
  7. Konus-A observation of GRB 070729
  8. Swift/UVOT detection of GRB070714B
  9. VLA upper limit on short hard burst GRB 070714B
  10. GRB070729: Swift/UVOT upper limits
  11. GRB 070729: Swift-XRT refined analysis
  12. GRB 070729, Swift-BAT refined analysis
  13. GRB 070729: Swift detection of a short hard burst
  14. GRB 070724B: Swift/UVOT Upper limits
  15. GRB070721A: Swift/UVOT Detection of a Weak Afterglow
  16. GRB 070724B: Swift-XRT afterglow likely candidate
  17. GRB 070724B: Swift-XRT afterglow candidates
  18. Four radio sources in Swift-XRT error box of GRB 070724
  19. GRB 060814 - Keck host detection and redshift
  20. Swift/UVOT refined analysis of GRB070724
  21. GRB 070724: Swift-XRT Team refined analysis
  22. GRB 070724, Swift-BAT refined analysis of a short burst
  23. GRB 070724: Swift detection of a burst
  24. GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
  25. GRB 070714B: Keck observations
  26. Swift/UVOT observations of GRB070721B optical afterglow.
  27. GRB 070721B, Further Swift-BAT refined analysis
  28. Swift/UVOT Observations of GRB070721A
  29. GRB 070721B: Swift-XRT refined analysis
  30. GRB 070721A: Swift/XRT refined analysis
  31. GRB 070721B, Swift-BAT refined analysis
  32. GRB 070721A, Swift-BAT refined analysis
  33. GRB070721B: A bright UVOT candidate
  34. GRB 070721B: Swift detection of a burst
  35. GRB 070721: Swift detection of a possible burst
  36. GRB 070714B: Swift/BAT and Suzaku/WAM joint spectral analysis
  37. GRB 070714B : Suzaku WAM observation of the prompt emission
  38. GRB 070714A: Swift-BAT T_zero
  39. GRB 070714A: Swift/UVOT Upper limits
  40. GRB 070714B: Swift/UVOT Upper Limits
  41. GRB 070714B: Swift-BAT spectral lag for the SHB
  42. GRB 070714A: Swift XRT refined analysis
  43. GRB070714B: Swift-XRT refined analysis
  44. GRB 070707: Swift-XRT follow-up observations
  45. GRB 070714B, Swift-BAT refined analysis of the short hard burst
  46. GRB 070714A, Swift-BAT refined analysis
  47. GRB 070714: Swift detection of a bright burst, possibly short
  48. Swift detection of a possible burst (Trigger 284850)
  49. GRB 070704: Suzaku/WAM observation of the prompt emission
  50. Updated Swift/UVOT calibration
  51. GRB 070707: object inside XRT error circle
  52. Swift/UVOT Observations of GRB070707
  53. Swift XRT observation of GRB 070707
  54. GRB070704: FAVOR optical observations
  55. GRB 070704: Swift-XRT refined analysis
  56. Swift/UVOT Observations of GRB070704
  57. GRB 070704, Swift-BAT refined analysis
  58. GRB 070704: Correction to GCN Circ 6594
  59. GRB 070704: Swift detection of a burst
  60. GRB 070628 Swift-UVOT Refined Analysis
  61. GRB 070628: NIR detection of afterglow
  62. GRB 070628, Swift-BAT refined analysis
  63. GRB 070628: TAROT La Silla observatory optical observations
  64. GRB 070628: Swift XRT refined analysis
  65. GRB 070628: Watcher Observations
  66. Swift UVOT Observations of GRB 070628
  67. GRB 070628: Swift detection of a possible burst
  68. INTEGRAL burst GRB070615: X-ray continued observations
  69. GRB 070616 : WIDGET simultaneous optical observations
  70. GRB 070616: Suzaku/WAM observation of the prompt emission
  71. GRB 070621: Swift/UVOT Upper Limits
  72. GRB 070621: Swift-BAT refined analysis
  73. GRB070621: Swift XRT refined analysis
  74. GRB 070621: UVOT-enhanced XRT position
  75. GRB070621: OPTIMA-Burst optical upper limit
  76. GRB 070621: TAROT Calern observatory optical observations
  77. GRB 070621: Watcher Observations
  78. GRB 070621: ROTSE-III Prompt Optical Limits
  79. GRB 070621: Swift detection of a burst
  80. GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
  81. Swift/UVOT detection of GRB070616 optical afterglow.
  82. GRB 070616, Swift-BAT further refined analysis
  83. GRB 070616: Swift XRT refined circular
  84. GRB 070616: BTA optical observations
  85. Swift/UVOT observations of GRB070616
  86. GRB 070616: TLS observation
  87. Swift XRT observations of the INTEGRAL burst GRB070615: Possible
  88. GRB 070616, Swift-BAT partial refined analysis
  89. GRB 070616: Swift detection of a burst
  90. UVOT Observations of INTEGRAL burst GRB070615
  91. SWIFT J195509.6+261406 (GRB 070610): further observations
  92. GRB 070612A: Rapid Decay
  93. GRB 070612A: Suzaku/WAM observation of the prompt emission
  94. SWIFT J195509.6+261406 / GRB 070610: OPTIMA-Burst observations
  95. GRB 070611: Watcher Observations
  96. Swift Trigger 282176 is Cygnus X-1
  97. GRB 070612A: MDM Observations
  98. GRB 070612B, Swift-BAT refined analysis
  99. GRB 070612A, Swift-BAT refined analysis
  100. GRB 070612B: Swift-XRT refined analysis

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