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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"

18636 results found.

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

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