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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"

27774 results found.

  1. GRB 050713B
  2. GRB050713: Liverpool Telescope prompt observations
  3. GRB050709: Candidate X-ray Afterglow from Chandra
  4. GRB 050713, R-band observations at NOT
  5. GRB 050713: Swift detection of Bright Burst
  6. GRB 050713A: ROTSE-III Optical Limits
  7. GRB050712: XRT refined analysis
  8. GRB 050709: Swift UVOT and XRT observations
  9. GRB 050712: Swift-BAT Refined Analysis
  10. GRB050712: UVOT candidate optical counterpart
  11. GRB 050712: Swift XRT afterglow position
  12. GRB 050712: Swift detection of a weak burst
  13. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  14. GRB 050626: Swift XRT observations
  15. GRB 050701
  16. GRB 050701, optical observations
  17. GRB 050701: Refined XRT analysis
  18. Swift UVOT observations of GRB 050701
  19. GRB050701: Swift-BAT Refined analysis
  20. GRB 050701: Swift XRT afterglow position
  21. Swift trigger 143708 is really GRB 050701
  22. GRB 050525A: Swift Late-Time Decay Rate
  23. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  24. XRF050509c: Radio Detection
  25. GRB 050416(a): Host Galaxy Redshift Determination
  26. GRB050607: refined analysis of prompt REM observations
  27. Swift/UVOT observations of GRB050607
  28. GRB 050607: RAPTOR-S Early Optical Limits
  29. GRB050607: KAIT optical limits
  30. GRB 050525a, Mid-Infrared Observations
  31. GRB 050607: MDM Observations
  32. GRB050607,optical observation
  33. GRB 050607 - XRT refined data analysis
  34. GRB050607 optical limit by "Pi of the Sky"
  35. GRB050607: Swift Detection of a long GRB
  36. Limits on a SN in the field of GRB 050509b
  37. GRB 050603 - XRT data analysis of the first day
  38. Konus-Wind observation of GRB 050603
  39. GRB 050603: Analysis of UVOT data
  40. GRB050603: Fading Afterglow observed by Swift UVOT
  41. GRB 050603: Swift XRT Position
  42. GRB050603: Radio Detection
  43. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  44. Swift/BAT Detection of GRB050603
  45. GRB 050408: jet break in the XRT light curve
  46. GRB050528, XRT observations
  47. Correction to GCN Circ 3502 on GRB 050528
  48. Swift-BAT GRB 050528: a soft burst
  49. Update on Swift-BAT GRB 050528 (Trigger 130679)
  50. Possible GRB050528: no candidate from Liverpool Telescope
  51. Swift-BAT detection of possible GRB 050528
  52. GRB 050509b: refined XRT/Chandra afterglow position analysis
  53. GRB050525a: optical upper limits
  54. GRB 050525B: Swift-BAT observations
  55. GRB050525A,optical observation
  56. GRB050525: Super-LOTIS observations
  57. GRB 050525, spectral lag pseudo-redshift
  58. GRB050306: optical afterglow not confirmed
  59. GRB 050525: BART optical observation
  60. GRB 050525A: BOOTES simultaneous optical observations
  61. GRB 050525A: Swift-BAT refined analysis
  62. Swift/UVOT UV and optical detections of GRB 050525
  63. Konus-Wind observation of GRB 050525
  64. GRB 050525: TAROT observations of the early afterglow
  65. INTEGRAL detection of GRB 050525
  66. GRB 050525: Optical observation
  67. GRB050525: ROTSE-III Refined Analysis
  68. GRB 050525 - Very Bright, Not Short
  69. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  70. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  71. XRF 050522: Swift XRT refined analysis
  72. Swift/UVOT observation of XRF 050522
  73. GRB 050509A: Further I-band imaging
  74. RBO Observations of GRB050522
  75. XRF 050522: Swift XRT observation
  76. GRB 050520: VLT/ULTRACAM observations
  77. Swift UVOT Observations of GRB 050520
  78. GRB 050520: Swift XRT refined analysis
  79. XRF050509C: Chandra Afterglow Detection
  80. XRF 050509c: Swift XRT Upper Limit
  81. RBO Observations of GRB050520
  82. GRB 050520: TAROT optical limit
  83. GRB 050520: Swift XRT position
  84. GRB 050520: OSN optical observations
  85. No Swift-BAT Lightcurves in real-time for next 3 weeks
  86. Swift-BAT trigger 122203 is not a real GRB
  87. XRF 050509C: REM NIR and Optical refined analysis
  88. GRB 050504: Swift XRT afterglow candidate has faded
  89. GRB 050509B: Subaru Optical Observations
  90. GRB050502b: Early Observation
  91. Refined Chandra analysis of GRB 050509b
  92. GRB050509b, SDSS pre-burst observations
  93. Chandra observation of GRB 050509b
  94. GRB 050509b: RAPTOR deep, early limits.
  95. GRB050509B: Optical/Infared observations
  96. GRB 050509b: Swift/UVOT follow-up measurements
  97. GRB 050509b Milagro GeV/TeV Observations
  98. GRB050509B: Optical observations at the Very Large Telescope
  99. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  100. GRB 050509a: Swift-BAT refined analysis

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