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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"

19599 results found.

  1. GRB 141225A: UVOT detection
  2. GRB 141225A: LT optical candidate
  3. GRB 141225A: Swift detection of a burst
  4. GRB 141221A: TAROT La Silla observatory optical observations
  5. Swift XRT and UVOT observations of GRB141222A
  6. GRB 141221A: Continued Skynet PROMPT-CTIO observations
  7. GRB 141221A: Swift/UVOT Detection
  8. GRB 141215A: further Swift-XRT observations and afterglow detection
  9. GRB 141221A: Fermi GBM observation
  10. GRB 141221A: Swift-XRT refined Analysis
  11. GRB 141221A: Swift-BAT refined analysis
  12. GRB141221A: GROND Afterglow Detection
  13. GRB 141221A: Enhanced Swift-XRT position
  14. GRB 141221A: Skynet PROMPT-CTIO observations of the optical afterglow
  15. GRB 141221A: LCOGT-McDonald optical afterglow observations
  16. Konus-Wind observation of GRB 141220A
  17. GRB 141221A: Swift detection of a burst with an optical counterpart
  18. GRB 141220A: Fermi GBM observation
  19. GRB 141220A: Swift-XRT refined Analysis
  20. GRB 141220A: Swift-BAT refined analysis
  21. GRB 141220A: Swift/UVOT Detection
  22. GRB 141220A: LT optical afterglow observations
  23. GRB141220A: 1.23m CAHA I-band observations
  24. GRB 141220A: Swift detection of a burst with an optical afterglow
  25. IPN Triangulation of GRB 141207A
  26. GRB 141207A: Suzaku WAM observation of the prompt emission
  27. GRB 141202A: Suzaku WAM observation of the prompt emission
  28. GRB 141215A: Swift-XRT observations
  29. GRB 141215A Tiled Swift observations
  30. IPN Triangulation of GRB 141215A (long/intense)
  31. GRB 141212A iTelescope observation
  32. GRB 141212A: Zadko observatory - Gingin optical observations
  33. Konus-Wind observation of GRB 141212B
  34. GRB 141212B: Swift-XRT refined Analysis
  35. GRB 141212A: Swift/UVOT Upper Limits
  36. GRB 141212B: Swift/UVOT Upper Limits
  37. GRB 141212B: Swift-BAT refined analysis
  38. GRB 141212A: Swift-BAT refined analysis
  39. GRB 141212B: Enhanced Swift-XRT position
  40. Swift detection of 4U 1700+24 (= V934 Her)
  41. GRB 141212A: Swift-XRT refined Analysis
  42. GRB 141212A: Khureltogot optical upper limit
  43. GRB 141212B: initial Swift/UVOT observations
  44. GRB 141212B: Swift/XRT preliminary localization
  45. GRB 141212A: Enhanced Swift-XRT position
  46. GRB 141212A: MASTER early optical observations
  47. GRB 141212A: Skynet R-COP Observations
  48. GRB 141212B: Swift detection of a burst
  49. GRB 141212A: Swift detection of a short burst
  50. GRB 141207A: Swift-XRT afterglow candidate detection
  51. GRB 141207A: Swift-UVOT Observations
  52. GRB 141207A: Fermi GBM detection
  53. GRB 141207A: Swift-XRT observations
  54. Konus-Wind observation of GRB 141130A
  55. GRB 141207A Tiled Swift observations
  56. GRB 141207A: Fermi-LAT Detection
  57. GRB141121A: Discovery Channel Telescope Optical Observations
  58. GRB 141205A: Swift/UVOT Upper Limits
  59. GRB 141205A: Fermi GBM detection
  60. GRB 141205A: XRT observations
  61. GRB 141205A Swift-BAT refined analysis
  62. GRB 141202A: Swift/UVOT Detection of a Variable Source Near the IPN Error Box
  63. GRB 141205A Short hard GRB found in ground analysis of BAT data
  64. GRB 141202A: Swift XRT observations
  65. GRB 141202A Tiled Swift observations
  66. IPN Triangulation of GRB 141202A (short/hard)
  67. GRB 141121A: Continued RATIR Optical Observations
  68. GRB 141130A: Swift-BAT refined analysis
  69. GRB 141130A: Swift/UVOT Detection
  70. GRB 141130A: Swift-XRT refined Analysis
  71. GRB 141130A: Enhanced Swift-XRT position
  72. GRB 141130A: Swift detection of a burst with an optical counterpart
  73. GRB 141121A: Continued RATIR Optical Observations
  74. GRB 141121A: Continued RATIR Optical Observations
  75. IPN Triangulation of GRB 141121A (initial episode)
  76. GRB 141121A: SPI-ACS/INTEGRAL observations
  77. GRB 141121A: RATIR Optical and NIR Observations
  78. Konus-Wind observation of GRB 141121A
  79. IPN Triangulation of GRB 141125A (short/hard)
  80. GRB 141121A: Continued RATIR Optical Observations
  81. GRB 141121A: Continued RATIR Optical Observations
  82. GRB 141121A: RATIR Optical Observations - Steeper Fading
  83. GRB 141121A: RATIR Optical Observations - Fading Again
  84. GRB 141121A: LCO-FTN rebrightening confirmation
  85. GRB 141121A: Continued RATIR Optical Observations - Rebrightening
  86. GRB 141121A: Continued RATIR Optical Observations
  87. GRB 141121A: Swift-XRT refined Analysis
  88. GRB 141121A: Swift/UVOT Detections
  89. GRB 141121A: RATIR Optical Observations
  90. GRB 141121A: Swift-BAT refined analysis
  91. GRB 141121A: LCO-FTN observations
  92. GRB 141121A: Enhanced Swift-XRT position
  93. GRB 141121A: GROND Afterglow candidate
  94. GRB141121A: BOOTES-2/TELMA upper limit
  95. GRB 141121A: Swift detection of a burst
  96. IPN Triangulation of GRB 141118A
  97. GRB 141104A: further Swift-XRT observations and afterglow candidate
  98. Swift Trigger 618673: probable noise event
  99. Trigger 618634: Swift detection of Vela X-1
  100. GRB 141109B: optical upper limits

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