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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"

18695 results found.

  1. GRB 050607: RAPTOR-S Early Optical Limits
  2. GRB050607: KAIT optical limits
  3. GRB 050607: MDM Observations
  4. GRB050607,optical observation
  5. GRB 050607 - XRT refined data analysis
  6. GRB050607 optical limit by "Pi of the Sky"
  7. GRB050607: Swift Detection of a long GRB
  8. GRB 050603 - XRT data analysis of the first day
  9. Konus-Wind observation of GRB 050603
  10. GRB 050603: Analysis of UVOT data
  11. GRB050603: Fading Afterglow observed by Swift UVOT
  12. GRB 050603: Swift XRT Position
  13. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  14. Swift/BAT Detection of GRB050603
  15. GRB 050408: jet break in the XRT light curve
  16. GRB050528, XRT observations
  17. Correction to GCN Circ 3502 on GRB 050528
  18. Swift-BAT GRB 050528: a soft burst
  19. Update on Swift-BAT GRB 050528 (Trigger 130679)
  20. Possible GRB050528: no candidate from Liverpool Telescope
  21. Swift-BAT detection of possible GRB 050528
  22. GRB 050509b: refined XRT/Chandra afterglow position analysis
  23. GRB050525a: optical upper limits
  24. GRB 050525B: Swift-BAT observations
  25. GRB050525A,optical observation
  26. GRB050525: Super-LOTIS observations
  27. GRB 050525, spectral lag pseudo-redshift
  28. GRB050306: optical afterglow not confirmed
  29. GRB 050525A: BOOTES simultaneous optical observations
  30. GRB 050525A: Swift-BAT refined analysis
  31. Swift/UVOT UV and optical detections of GRB 050525
  32. Konus-Wind observation of GRB 050525
  33. GRB 050525: TAROT observations of the early afterglow
  34. INTEGRAL detection of GRB 050525
  35. GRB 050525: Optical observation
  36. GRB050525: ROTSE-III Refined Analysis
  37. GRB 050525 - Very Bright, Not Short
  38. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  39. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  40. XRF 050522: Swift XRT refined analysis
  41. Swift/UVOT observation of XRF 050522
  42. GRB 050509A: Further I-band imaging
  43. RBO Observations of GRB050522
  44. XRF 050522: Swift XRT observation
  45. GRB 050520: VLT/ULTRACAM observations
  46. Swift UVOT Observations of GRB 050520
  47. GRB 050520: Swift XRT refined analysis
  48. XRF050509C: Chandra Afterglow Detection
  49. XRF 050509c: Swift XRT Upper Limit
  50. RBO Observations of GRB050520
  51. GRB 050520: TAROT optical limit
  52. GRB 050520: Swift XRT position
  53. No Swift-BAT Lightcurves in real-time for next 3 weeks
  54. Swift-BAT trigger 122203 is not a real GRB
  55. GRB 050504: Swift XRT afterglow candidate has faded
  56. GRB 050509B: Subaru Optical Observations
  57. GRB050502b: Early Observation
  58. Refined Chandra analysis of GRB 050509b
  59. GRB050509b, SDSS pre-burst observations
  60. Chandra observation of GRB 050509b
  61. GRB 050509b: RAPTOR deep, early limits.
  62. GRB050509B: Optical/Infared observations
  63. GRB 050509b: Swift/UVOT follow-up measurements
  64. GRB 050509b Milagro GeV/TeV Observations
  65. GRB050509B: Optical observations at the Very Large Telescope
  66. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  67. GRB 050509a: Swift-BAT refined analysis
  68. GRB 050509B: WSRT Radio Observations
  69. GRB 050505: SARA Observations
  70. Swift UVOT Follow-up Observations of GRB 050509B
  71. GRB 050509B, Optical Observations
  72. GRB 050509B: Swift/XRT refined analysis
  73. GRB050509a: Swift UVOT observations
  74. GRB 050509b: Optical observations
  75. GRB 050509b: Possible Optical Counterpart
  76. GRB 050509A: Optical observations
  77. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  78. GRB 050509b: optical observations
  79. GRB 050509b: Swift XRT Position
  80. GRB 050509B: ROTSE-III Optical Limits
  81. Swift Detection of GRB050509b: A short duration burst
  82. GRB 050509a: Swift XRT Position
  83. Swift Detection of the Burst GRB050509
  84. Swift-BAT detection of GRB 050507
  85. GRB 050505: early time observations
  86. GRB 050505 - Faulkes Telescope North observations
  87. GRB 050502a: Swift XRT Upper Limit
  88. GRB 050505, simultaneous optical observation
  89. GRB 050505: Further Swift UVOT observations.
  90. GRB050416A : 1 GHz limit from GMRT
  91. GRB 050505 UVOT
  92. GRB 050505: Swift XRT Position
  93. GRB050505 Swift-BAT refined analysis
  94. GRB 050416b:Swift XRT afterglow upper limits
  95. GRB 050416b:Swift XRT afterglow upper limits
  96. Swift-BAT detection of GRB050505
  97. GRB 050504: Swift XRT position
  98. Swift UVOT observation of GRB 050504
  99. GRB 050502b, V band Observations
  100. Renewal of SGR 1806-20 activity

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