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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19594 results found.

  1. GRB 141221A: Continued Skynet PROMPT-CTIO observations
  2. GRB 141221A: Swift/UVOT Detection
  3. GRB 141215A: further Swift-XRT observations and afterglow detection
  4. GRB 141221A: Fermi GBM observation
  5. GRB 141221A: Swift-XRT refined Analysis
  6. GRB 141221A: Swift-BAT refined analysis
  7. GRB141221A: GROND Afterglow Detection
  8. GRB 141221A: Enhanced Swift-XRT position
  9. GRB 141221A: Skynet PROMPT-CTIO observations of the optical afterglow
  10. GRB 141221A: LCOGT-McDonald optical afterglow observations
  11. Konus-Wind observation of GRB 141220A
  12. GRB 141221A: Swift detection of a burst with an optical counterpart
  13. GRB 141220A: Fermi GBM observation
  14. GRB 141220A: Swift-XRT refined Analysis
  15. GRB 141220A: Swift-BAT refined analysis
  16. GRB 141220A: Swift/UVOT Detection
  17. GRB 141220A: LT optical afterglow observations
  18. GRB141220A: 1.23m CAHA I-band observations
  19. GRB 141220A: Swift detection of a burst with an optical afterglow
  20. IPN Triangulation of GRB 141207A
  21. GRB 141207A: Suzaku WAM observation of the prompt emission
  22. GRB 141202A: Suzaku WAM observation of the prompt emission
  23. GRB 141215A: Swift-XRT observations
  24. GRB 141215A Tiled Swift observations
  25. IPN Triangulation of GRB 141215A (long/intense)
  26. GRB 141212A iTelescope observation
  27. GRB 141212A: Zadko observatory - Gingin optical observations
  28. Konus-Wind observation of GRB 141212B
  29. GRB 141212B: Swift-XRT refined Analysis
  30. GRB 141212A: Swift/UVOT Upper Limits
  31. GRB 141212B: Swift/UVOT Upper Limits
  32. GRB 141212B: Swift-BAT refined analysis
  33. GRB 141212A: Swift-BAT refined analysis
  34. GRB 141212B: Enhanced Swift-XRT position
  35. Swift detection of 4U 1700+24 (= V934 Her)
  36. GRB 141212A: Swift-XRT refined Analysis
  37. GRB 141212A: Khureltogot optical upper limit
  38. GRB 141212B: initial Swift/UVOT observations
  39. GRB 141212B: Swift/XRT preliminary localization
  40. GRB 141212A: Enhanced Swift-XRT position
  41. GRB 141212A: MASTER early optical observations
  42. GRB 141212A: Skynet R-COP Observations
  43. GRB 141212B: Swift detection of a burst
  44. GRB 141212A: Swift detection of a short burst
  45. GRB 141207A: Swift-XRT afterglow candidate detection
  46. GRB 141207A: Swift-UVOT Observations
  47. GRB 141207A: Fermi GBM detection
  48. GRB 141207A: Swift-XRT observations
  49. Konus-Wind observation of GRB 141130A
  50. GRB 141207A Tiled Swift observations
  51. GRB 141207A: Fermi-LAT Detection
  52. GRB141121A: Discovery Channel Telescope Optical Observations
  53. GRB 141205A: Swift/UVOT Upper Limits
  54. GRB 141205A: Fermi GBM detection
  55. GRB 141205A: XRT observations
  56. GRB 141205A Swift-BAT refined analysis
  57. GRB 141202A: Swift/UVOT Detection of a Variable Source Near the IPN Error Box
  58. GRB 141205A Short hard GRB found in ground analysis of BAT data
  59. GRB 141202A: Swift XRT observations
  60. GRB 141202A Tiled Swift observations
  61. IPN Triangulation of GRB 141202A (short/hard)
  62. GRB 141121A: Continued RATIR Optical Observations
  63. GRB 141130A: Swift-BAT refined analysis
  64. GRB 141130A: Swift/UVOT Detection
  65. GRB 141130A: Swift-XRT refined Analysis
  66. GRB 141130A: Enhanced Swift-XRT position
  67. GRB 141130A: Swift detection of a burst with an optical counterpart
  68. GRB 141121A: Continued RATIR Optical Observations
  69. GRB 141121A: Continued RATIR Optical Observations
  70. IPN Triangulation of GRB 141121A (initial episode)
  71. GRB 141121A: SPI-ACS/INTEGRAL observations
  72. GRB 141121A: RATIR Optical and NIR Observations
  73. Konus-Wind observation of GRB 141121A
  74. IPN Triangulation of GRB 141125A (short/hard)
  75. GRB 141121A: Continued RATIR Optical Observations
  76. GRB 141121A: Continued RATIR Optical Observations
  77. GRB 141121A: RATIR Optical Observations - Steeper Fading
  78. GRB 141121A: RATIR Optical Observations - Fading Again
  79. GRB 141121A: LCO-FTN rebrightening confirmation
  80. GRB 141121A: Continued RATIR Optical Observations - Rebrightening
  81. GRB 141121A: Continued RATIR Optical Observations
  82. GRB 141121A: Swift-XRT refined Analysis
  83. GRB 141121A: Swift/UVOT Detections
  84. GRB 141121A: RATIR Optical Observations
  85. GRB 141121A: Swift-BAT refined analysis
  86. GRB 141121A: LCO-FTN observations
  87. GRB 141121A: Enhanced Swift-XRT position
  88. GRB 141121A: GROND Afterglow candidate
  89. GRB141121A: BOOTES-2/TELMA upper limit
  90. GRB 141121A: Swift detection of a burst
  91. IPN Triangulation of GRB 141118A
  92. GRB 141104A: further Swift-XRT observations and afterglow candidate
  93. Swift Trigger 618673: probable noise event
  94. Trigger 618634: Swift detection of Vela X-1
  95. GRB 141109B: optical upper limits
  96. GRB 141015A: TAROT La Silla observatory optical observations
  97. GRB 141022A: TAROT La Silla observatory optical observations
  98. GRB 141031A: TAROT La Silla observatory optical observations
  99. GRB 141109A: TAROT La Silla observatory optical observations
  100. GRB 141109A: AAO optical observations

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