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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"

19551 results found.

  1. GRB 150101B/Swift J123205.1-105602: TNG NIR follow-up
  2. GRB 150120A: Swift/UVOT Upper Limits
  3. GRB 150101B/Swift J123205.1-105602, deep VLT observations
  4. GRB 150120B: Enhanced Swift-XRT position
  5. GRB 150101B/Swift J123205.1-105602: XMM-Newton observation
  6. GRB 150120A: Enhanced Swift-XRT position
  7. GRB 150120B: P60 optical afterglow
  8. GRB 150120B: Swift detection of a burst
  9. GRB 150120A: Gemini-North optical imaging
  10. GRB 150120A: Swift detection of a possibly-short burst
  11. GRB 150101B/Swift J123205.1-105602: continued WSRT radio and VLT optical observations
  12. GRB 150118B: Fermi GBM Detection
  13. GRB 150118B: Fermi-LAT detection
  14. GRB 150110B: Khureltogot optical upper limit
  15. The Swift Detection of a Large Flare from the RS CVn Binary SZ Psc
  16. Swift detection of the variable star SZ Psc
  17. GRB 150110C: Swift/UVOT Upper Limits
  18. GRB 150110B: Swift-BAT refined analysis
  19. GRB 150110B: Swift/UVOT Upper Limits
  20. GRB 150110B: Fermi GBM Detection
  21. GRB 150110B: Enhanced Swift-XRT position
  22. GRB 150110A: Fermi GBM Detection
  23. GRB 150110B: Swift detection of a burst
  24. GRB 150101B/Swift J123205.1-105602: Chandra observations
  25. GRB 150101B / Swift J123205.1-105602: 9.8 GHz VLA observations
  26. Fermi GBM trigger 150108121 is not a GRB
  27. Swift detection of 4U 1700+24 (= V* V934 Her)
  28. GRB 150101B: Fermi GBM detection
  29. GRB 150103A: Swift/UVOT Upper Limits
  30. GRB 150103A: Zadko observatory - Gingin optical observations
  31. GRB 150103A: Enhanced Swift-XRT position
  32. GRB 150103A: Swift detection of a burst
  33. Swift J123205.1-105602: XRT and UVOT observations of soft short burst source
  34. Short burst found in ground analysis of Swift-BAT data
  35. GRB 150101A: Swift/UVOT Upper Limits
  36. GRB 150101A: Enhanced Swift-XRT position
  37. GRB 150101A: Swift detection of a short burst
  38. Swift-XRT and UVOT follow-up of iPTF14jko (GRB 141230A)
  39. GRB 141229A Swift-BAT observations
  40. GRB 141230A: Nanshan optical obsrvations
  41. GRB 141229A: 1.23m CAHA optical observations
  42. GRB 141229A: Nanshan optical upper limit
  43. Christmas GRB 141225A: GROND Observations
  44. GRB 141225A: MITSuME Okayama upper limits
  45. GRB 141225A: TAROT Calern observatory optical observations
  46. GRB 141225A: Swift/UVOT refined analysis
  47. GRB 141225A: very early T60 observations
  48. GRB 141225A: Swift-BAT refined analysis
  49. GRB 141225A: Nanshan very early optical observations
  50. GRB 141225A: Enhanced Swift-XRT position
  51. GRB 141225A: Optical aftergow confirmation
  52. GRB 141225A: 1.23m CAHA optical observations
  53. GRB 141225A: Swift detection of a burst
  54. GRB 141221A: TAROT La Silla observatory optical observations
  55. Swift XRT and UVOT observations of GRB141222A
  56. GRB 141221A: MITSuME Akeno upper limits
  57. GRB 141221A: Continued Skynet PROMPT-CTIO observations
  58. GRB 141221A: Swift/UVOT Detection
  59. GRB 141215A: further Swift-XRT observations and afterglow detection
  60. GRB 141221A: Fermi GBM observation
  61. GRB 141220A: MITSuME Akeno upper limits
  62. GRB 141221A: Swift-XRT refined Analysis
  63. GRB141221A: GROND Afterglow Detection
  64. GRB 141221A: Enhanced Swift-XRT position
  65. GRB 141221A: Skynet PROMPT-CTIO observations of the optical afterglow
  66. GRB141221A: REM afterglow
  67. GRB 141221A: Swift detection of a burst with an optical counterpart
  68. GRB 141220A: Fermi GBM observation
  69. GRB 141220A: MITSuME Okayama upper limits
  70. GRB 141220A: Swift-XRT refined Analysis
  71. GRB 141220A: Swift/UVOT Detection
  72. GRB141220A: 1.23m CAHA I-band observations
  73. GRB 141220A: Swift detection of a burst with an optical afterglow
  74. IPN Triangulation of GRB 141215A (long/intense)
  75. GRB 141212A iTelescope observation
  76. GRB 141212A: Zadko observatory - Gingin optical observations
  77. GRB 141212B: MITSuME Akeno upper limits
  78. GRB 141212A: Swift/UVOT Upper Limits
  79. GRB 141212B: Swift/UVOT Upper Limits
  80. GRB 141212A: VLA upper limit
  81. GRB 141212A: Gemini-N spectroscopy and photometry
  82. GRB 141212B: Enhanced Swift-XRT position
  83. Swift detection of 4U 1700+24 (= V934 Her)
  84. GRB 141212A: MITSuME Okayama upper limits
  85. GRB 141212A: extended object within the XRT error circle
  86. GRB 141212A: Khureltogot optical upper limit
  87. GRB 141212A: 1.23m CAHA I-band observations
  88. GRB 141212B: initial Swift/UVOT observations
  89. GRB 141212A: Enhanced Swift-XRT position
  90. GRB 141212A: Skynet R-COP Observations
  91. GRB 141212A: MITSuME Akeno upper limits
  92. GRB 141212B: Swift detection of a burst
  93. GRB 141212A: Swift detection of a short burst
  94. GRB 141207A: Swift-XRT afterglow candidate detection
  95. GRB141202A: Discovery Channel Telescope Optical Observations
  96. GRB141207A: Discovery Channel Telescope Optical Observations
  97. GRB 141207A: Swift-XRT observations
  98. GRB141121A: Discovery Channel Telescope Optical Observations
  99. GRB 141205A: Swift/UVOT Upper Limits
  100. GRB 141205A: Nanshan optical upper limit

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