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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"

18476 results found.

  1. GRB 050701: Swift XRT afterglow position
  2. Swift trigger 143708 is really GRB 050701
  3. GRB 050525A: Swift Late-Time Decay Rate
  4. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  5. GRB 050416(a): Host Galaxy Redshift Determination
  6. Swift/UVOT observations of GRB050607
  7. GRB 050607: RAPTOR-S Early Optical Limits
  8. GRB050607: KAIT optical limits
  9. GRB 050607: MDM Observations
  10. GRB050607,optical observation
  11. GRB 050607 - XRT refined data analysis
  12. GRB050607 optical limit by "Pi of the Sky"
  13. GRB050607: Swift Detection of a long GRB
  14. GRB 050603 - XRT data analysis of the first day
  15. Konus-Wind observation of GRB 050603
  16. GRB 050603: Analysis of UVOT data
  17. GRB050603: Fading Afterglow observed by Swift UVOT
  18. GRB 050603: Swift XRT Position
  19. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  20. Swift/BAT Detection of GRB050603
  21. GRB 050408: jet break in the XRT light curve
  22. GRB050528, XRT observations
  23. Correction to GCN Circ 3502 on GRB 050528
  24. Swift-BAT GRB 050528: a soft burst
  25. Update on Swift-BAT GRB 050528 (Trigger 130679)
  26. Possible GRB050528: no candidate from Liverpool Telescope
  27. Swift-BAT detection of possible GRB 050528
  28. GRB 050509b: refined XRT/Chandra afterglow position analysis
  29. GRB050525a: optical upper limits
  30. GRB 050525B: Swift-BAT observations
  31. GRB050525A,optical observation
  32. GRB050525: Super-LOTIS observations
  33. GRB 050525, spectral lag pseudo-redshift
  34. GRB050306: optical afterglow not confirmed
  35. GRB 050525A: BOOTES simultaneous optical observations
  36. GRB 050525A: Swift-BAT refined analysis
  37. Swift/UVOT UV and optical detections of GRB 050525
  38. Konus-Wind observation of GRB 050525
  39. GRB 050525: TAROT observations of the early afterglow
  40. INTEGRAL detection of GRB 050525
  41. GRB 050525: Optical observation
  42. GRB050525: ROTSE-III Refined Analysis
  43. GRB 050525 - Very Bright, Not Short
  44. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  45. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  46. XRF 050522: Swift XRT refined analysis
  47. Swift/UVOT observation of XRF 050522
  48. GRB 050509A: Further I-band imaging
  49. RBO Observations of GRB050522
  50. XRF 050522: Swift XRT observation
  51. GRB 050520: VLT/ULTRACAM observations
  52. Swift UVOT Observations of GRB 050520
  53. GRB 050520: Swift XRT refined analysis
  54. XRF050509C: Chandra Afterglow Detection
  55. XRF 050509c: Swift XRT Upper Limit
  56. RBO Observations of GRB050520
  57. GRB 050520: TAROT optical limit
  58. GRB 050520: Swift XRT position
  59. No Swift-BAT Lightcurves in real-time for next 3 weeks
  60. Swift-BAT trigger 122203 is not a real GRB
  61. GRB 050504: Swift XRT afterglow candidate has faded
  62. GRB 050509B: Subaru Optical Observations
  63. GRB050502b: Early Observation
  64. Refined Chandra analysis of GRB 050509b
  65. GRB050509b, SDSS pre-burst observations
  66. Chandra observation of GRB 050509b
  67. GRB 050509b: RAPTOR deep, early limits.
  68. GRB050509B: Optical/Infared observations
  69. GRB 050509b: Swift/UVOT follow-up measurements
  70. GRB 050509b Milagro GeV/TeV Observations
  71. GRB050509B: Optical observations at the Very Large Telescope
  72. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  73. GRB 050509a: Swift-BAT refined analysis
  74. GRB 050509B: WSRT Radio Observations
  75. GRB 050505: SARA Observations
  76. Swift UVOT Follow-up Observations of GRB 050509B
  77. GRB 050509B, Optical Observations
  78. GRB 050509B: Swift/XRT refined analysis
  79. GRB050509a: Swift UVOT observations
  80. GRB 050509b: Optical observations
  81. GRB 050509b: Possible Optical Counterpart
  82. GRB 050509A: Optical observations
  83. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  84. GRB 050509b: optical observations
  85. GRB 050509b: Swift XRT Position
  86. GRB 050509B: ROTSE-III Optical Limits
  87. Swift Detection of GRB050509b: A short duration burst
  88. GRB 050509a: Swift XRT Position
  89. Swift Detection of the Burst GRB050509
  90. Swift-BAT detection of GRB 050507
  91. GRB 050505: early time observations
  92. GRB 050505 - Faulkes Telescope North observations
  93. GRB 050502a: Swift XRT Upper Limit
  94. GRB 050505, simultaneous optical observation
  95. GRB 050505: Further Swift UVOT observations.
  96. GRB050416A : 1 GHz limit from GMRT
  97. GRB 050505 UVOT
  98. GRB 050505: Swift XRT Position
  99. GRB050505 Swift-BAT refined analysis
  100. GRB 050416b:Swift XRT afterglow upper limits

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