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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"

18655 results found.

  1. GRB 070809: Swift detection of a short burst
  2. GCN Swift XRT update position notices and enhanced position circulars
  3. GRB 070808: Swift XRT refined analysis
  4. GRB 070808, Swift-BAT refined analysis
  5. GRB070808 - SDSS Pre-Burst Observations
  6. GRB 070808: ROTSE-III Optical Limits
  7. GRB 070808: Swift detection of a burst
  8. GRB070805 XRT and UVOT afterglow candidate
  9. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  10. Swift/UVOT observations of GRB070805
  11. GRB 070805, Swift-BAT refined analysis
  12. GRB 070805: Swift XRT initial analysis.
  13. GRB 070805: Swift/UVOT initial analysis
  14. GRB 070805: Swift detection of a burst
  15. UVOT observations of SAXJ1810.8-2609
  16. Swift detection of a outburst from SAX J1810.8-2609
  17. VLA non-detection of GRB 070721B
  18. GRB 070802: REM optical observations
  19. GRB 070724B: Swift-XRT afterglow confirmation
  20. GRB 070802: Swift-XRT refined analysis
  21. GRB070802: Swift/UVOT upper limits
  22. GRB 070802, Swift-BAT refined analysis
  23. GRB 070802: refined Swift XRT position
  24. GRB 070802: GROND J band candidate
  25. GRB 070802: Swift detection of a burst
  26. GRB 070731, Swift-BAT refined analysis
  27. Konus-A observation of GRB 070729
  28. Swift/UVOT detection of GRB070714B
  29. VLA upper limit on short hard burst GRB 070714B
  30. GRB070729: Swift/UVOT upper limits
  31. GRB 070729: Swift-XRT refined analysis
  32. GRB 070729, Swift-BAT refined analysis
  33. GRB 070729: Swift detection of a short hard burst
  34. GRB 070724B: Swift/UVOT Upper limits
  35. GRB070721A: Swift/UVOT Detection of a Weak Afterglow
  36. GRB 070724B: Swift-XRT afterglow likely candidate
  37. GRB 070724B: Swift-XRT afterglow candidates
  38. Four radio sources in Swift-XRT error box of GRB 070724
  39. GRB 060814 - Keck host detection and redshift
  40. Swift/UVOT refined analysis of GRB070724
  41. GRB 070724: Swift-XRT Team refined analysis
  42. GRB 070724, Swift-BAT refined analysis of a short burst
  43. GRB 070724: Swift detection of a burst
  44. GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
  45. GRB 070714B: Keck observations
  46. Swift/UVOT observations of GRB070721B optical afterglow.
  47. GRB 070721B, Further Swift-BAT refined analysis
  48. Swift/UVOT Observations of GRB070721A
  49. GRB 070721B: Swift-XRT refined analysis
  50. GRB 070721A: Swift/XRT refined analysis
  51. GRB 070721B, Swift-BAT refined analysis
  52. GRB 070721A, Swift-BAT refined analysis
  53. GRB070721B: A bright UVOT candidate
  54. GRB 070721B: Swift detection of a burst
  55. GRB 070721: Swift detection of a possible burst
  56. GRB 070714B: Swift/BAT and Suzaku/WAM joint spectral analysis
  57. GRB 070714B : Suzaku WAM observation of the prompt emission
  58. GRB 070714A: Swift-BAT T_zero
  59. GRB 070714A: Swift/UVOT Upper limits
  60. GRB 070714B: Swift/UVOT Upper Limits
  61. GRB 070714B: Swift-BAT spectral lag for the SHB
  62. GRB 070714A: Swift XRT refined analysis
  63. GRB070714B: Swift-XRT refined analysis
  64. GRB 070707: Swift-XRT follow-up observations
  65. GRB 070714B, Swift-BAT refined analysis of the short hard burst
  66. GRB 070714A, Swift-BAT refined analysis
  67. GRB 070714: Swift detection of a bright burst, possibly short
  68. Swift detection of a possible burst (Trigger 284850)
  69. GRB 070704: Suzaku/WAM observation of the prompt emission
  70. Updated Swift/UVOT calibration
  71. GRB 070707: object inside XRT error circle
  72. Swift/UVOT Observations of GRB070707
  73. Swift XRT observation of GRB 070707
  74. GRB070704: FAVOR optical observations
  75. GRB 070704: Swift-XRT refined analysis
  76. Swift/UVOT Observations of GRB070704
  77. GRB 070704, Swift-BAT refined analysis
  78. GRB 070704: Correction to GCN Circ 6594
  79. GRB 070704: Swift detection of a burst
  80. GRB 070628 Swift-UVOT Refined Analysis
  81. GRB 070628: NIR detection of afterglow
  82. GRB 070628, Swift-BAT refined analysis
  83. GRB 070628: TAROT La Silla observatory optical observations
  84. GRB 070628: Swift XRT refined analysis
  85. GRB 070628: Watcher Observations
  86. Swift UVOT Observations of GRB 070628
  87. GRB 070628: Swift detection of a possible burst
  88. INTEGRAL burst GRB070615: X-ray continued observations
  89. GRB 070616 : WIDGET simultaneous optical observations
  90. GRB 070616: Suzaku/WAM observation of the prompt emission
  91. GRB 070621: Swift/UVOT Upper Limits
  92. GRB 070621: Swift-BAT refined analysis
  93. GRB070621: Swift XRT refined analysis
  94. GRB 070621: UVOT-enhanced XRT position
  95. GRB070621: OPTIMA-Burst optical upper limit
  96. GRB 070621: TAROT Calern observatory optical observations
  97. GRB 070621: Watcher Observations
  98. GRB 070621: ROTSE-III Prompt Optical Limits
  99. GRB 070621: Swift detection of a burst
  100. GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz

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