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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"

19193 results found.

  1. GRB 080229: Enhanced Swift-XRT position
  2. UVOT analysis for GRB080229
  3. GRB 080229, Swift-BAT refined analysis
  4. GRB 080229: Faulkes Telescope South optical limit
  5. GRB 080229A: ROTSE-III Optical Limits
  6. GRB 080229: Swift detection of a bright burst
  7. Swift-XRT improved positions, and new redshift limits.
  8. ESO optical and NIR observations of GRB 080218B
  9. GRB 080204: Suzaku WAM observation of the prompt emission
  10. GRB 080218B, Swift-BAT refined analysis
  11. GRB 080218B: Swift-XRT refined analysis
  12. Swift/UVOT observations of GRB080218B
  13. GRB 080218B: Enhanced Swift-XRT position
  14. GRB 080218B: GROND upper limits
  15. GRB 080218A, Swift-BAT refined analysis
  16. GRB080218B: Watcher prompt limit
  17. GRB 080218B: Swift detection of a burst
  18. GRB 080218: Swift detection of a burst
  19. Swift-XRT and UVOT observations of the IPN burst GRB 080211
  20. VLA radio upper limit on GRB 080212
  21. Swift/UVOT refined analysis of GRB080212
  22. GRB 080212, Swift-BAT refined analysis
  23. GRB 080212: GROND detects afterglow
  24. GRB 080212: optical observations
  25. GRB 080212: Enhanced Swift-XRT position
  26. GRB 080212: Swift-XRT Team refined analysis
  27. GRB 080210: Keck photometry
  28. VLA non-detection of GRB 080210
  29. GRB 080212: Swift detection of a burst
  30. GRB 080210: Swift/UVOT Refined Analysis
  31. GRB 080210, Swift-BAT refined analysis
  32. GRB 080210: Super-LOTIS observations
  33. GRB 080210: Swift-XRT Refined Analysis
  34. GRB 080210: Enhanced Swift-XRT position
  35. GRB 080210: GOND detection in all bands and redshift upper limit
  36. GRB080210 - SDSS Pre-Burst Observations
  37. GRB 080210: Swift detection of a burst with optical afterglow
  38. GRB 080210: TAROT La Silla observatory optical detection
  39. GRB 080207: GROND upper limits
  40. GRB 080207, Swift-BAT refined analysis
  41. Swift detection of AX J1749.1-2639
  42. GRB 080207, Swift-BAT refined analysis
  43. Swift Trigger 302777 is not a GRB
  44. GRB080207: Swift/UVOT refined analysis
  45. GRB 080207: TAROT Calern observatory optical observations
  46. GRB 080207: Swift-XRT Refined Analysis
  47. GRB 080207: Enhanced Swift-XRT position
  48. GRB 080207: Swift detection of a burst
  49. GRB 080205 optical upper limit
  50. VLA radio upper limit on GRB 080205
  51. GRB 080205, Swift-BAT refined analysis
  52. IPN localization of very hard GRB 080204
  53. GRB 080205: Swift XRT refined analysis
  54. GRB 080205: OA evolution from KAIT observations
  55. GRB 080205: Swift/UVOT observations
  56. GRB 080205: Enhanced Swift-XRT position
  57. GRB 080205: KAIT OA detection
  58. GRB 080205: Swift detection of a burst
  59. Swift-BAT Trigger #302454, correction of GCN notice, update on AX J1749.1-2639
  60. GRB 080130: Swift-BAT refined analysis
  61. GRB 080130: further Swift XRT observations confirm fading source
  62. GRB 080129: Swift/UVOT Refined Upper Limits
  63. Swift/UVOT observations of GRB080130
  64. GRB 080130(?): Swift XRT observation
  65. GRB 080129: Swift-XRT refined analysis
  66. GRB 080129: KAIT optical limits
  67. GRB 080129, Swift-BAT refined analysis
  68. GRB 080129: TAROT La Silla observatory optical observations
  69. GRB 080129: Gemini-South photometry
  70. GRB 080129: GROND detection in all bands, and fading
  71. GRB 080129: GROND detection of the optical/NIR afterglow, and fading
  72. GRB 080129: Enhanced Swift-XRT position
  73. GRB 080129: Swift XRT position
  74. GRB 080129 (?): UVOT Upper Limits
  75. GRB 080129 (?): Swift detection of a possible burst
  76. A new website of high-level data products for Swift GRBs
  77. GRB 080121: Upper limit on X-ray afterglow
  78. GRB 080123 : Suzaku WAM observation of the prompt emission
  79. Swift trigger(=301779) is not a GRB
  80. GRB 080121: Swift/UVOT upper limits
  81. SNe 2008D and 2007uy: Chandra Detections
  82. GRB 080121: Enhanced Swift-XRT position
  83. Two non-burst Swift SubThreshold triggers
  84. IPN triangulation of GRB080122
  85. GRB 080121: Nearby SDSS galaxies
  86. GRB 080121: Swift-BAT detection of a very weak, short burst
  87. GRB 080123: Swift-XRT refined analysis
  88. GRB 080123: Swift/UVOT refined analysis
  89. GRB 080123, Swift-BAT refined analysis
  90. GRB 080123: Enhanced Swift-XRT position
  91. GRB 080123: Swift detection of a short burst
  92. VLA radio upper limit on GRB 080120
  93. GRB 080120: Swift-XRT refined analysis
  94. UVOT detection of GRB080120
  95. GRB 080120: GROND detection
  96. GRB080120: Swift XRT position
  97. Swift UVOT Monitoring of the SN 2008D Brightening (Transient in NGC 2770)
  98. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  99. XRB 080109/SN 2008D: Early decline in brightness and change in colors
  100. XRB 080109/SN 2008D:PAIRITEL NIR observations and t_0 from Swift

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