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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"

19597 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. GRB 050416(a): Host Galaxy Redshift Determination
  25. Swift/UVOT observations of GRB050607
  26. GRB 050607: RAPTOR-S Early Optical Limits
  27. GRB050607: KAIT optical limits
  28. GRB 050607: MDM Observations
  29. GRB050607,optical observation
  30. GRB 050607 - XRT refined data analysis
  31. GRB050607 optical limit by "Pi of the Sky"
  32. GRB050607: Swift Detection of a long GRB
  33. GRB 050603 - XRT data analysis of the first day
  34. Konus-Wind observation of GRB 050603
  35. GRB 050603: Analysis of UVOT data
  36. GRB050603: Fading Afterglow observed by Swift UVOT
  37. GRB 050603: Swift XRT Position
  38. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  39. Swift/BAT Detection of GRB050603
  40. GRB 050408: jet break in the XRT light curve
  41. GRB050528, XRT observations
  42. Correction to GCN Circ 3502 on GRB 050528
  43. Swift-BAT GRB 050528: a soft burst
  44. Update on Swift-BAT GRB 050528 (Trigger 130679)
  45. Possible GRB050528: no candidate from Liverpool Telescope
  46. Swift-BAT detection of possible GRB 050528
  47. GRB 050509b: refined XRT/Chandra afterglow position analysis
  48. GRB050525a: optical upper limits
  49. GRB 050525B: Swift-BAT observations
  50. GRB050525A,optical observation
  51. GRB050525: Super-LOTIS observations
  52. GRB 050525, spectral lag pseudo-redshift
  53. GRB050306: optical afterglow not confirmed
  54. GRB 050525A: BOOTES simultaneous optical observations
  55. GRB 050525A: Swift-BAT refined analysis
  56. Swift/UVOT UV and optical detections of GRB 050525
  57. Konus-Wind observation of GRB 050525
  58. GRB 050525: TAROT observations of the early afterglow
  59. INTEGRAL detection of GRB 050525
  60. GRB 050525: Optical observation
  61. GRB050525: ROTSE-III Refined Analysis
  62. GRB 050525 - Very Bright, Not Short
  63. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  64. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  65. XRF 050522: Swift XRT refined analysis
  66. Swift/UVOT observation of XRF 050522
  67. GRB 050509A: Further I-band imaging
  68. RBO Observations of GRB050522
  69. XRF 050522: Swift XRT observation
  70. GRB 050520: VLT/ULTRACAM observations
  71. Swift UVOT Observations of GRB 050520
  72. GRB 050520: Swift XRT refined analysis
  73. XRF050509C: Chandra Afterglow Detection
  74. XRF 050509c: Swift XRT Upper Limit
  75. RBO Observations of GRB050520
  76. GRB 050520: TAROT optical limit
  77. GRB 050520: Swift XRT position
  78. No Swift-BAT Lightcurves in real-time for next 3 weeks
  79. Swift-BAT trigger 122203 is not a real GRB
  80. GRB 050504: Swift XRT afterglow candidate has faded
  81. GRB 050509B: Subaru Optical Observations
  82. GRB050502b: Early Observation
  83. Refined Chandra analysis of GRB 050509b
  84. GRB050509b, SDSS pre-burst observations
  85. Chandra observation of GRB 050509b
  86. GRB 050509b: RAPTOR deep, early limits.
  87. GRB050509B: Optical/Infared observations
  88. GRB 050509b: Swift/UVOT follow-up measurements
  89. GRB 050509b Milagro GeV/TeV Observations
  90. GRB050509B: Optical observations at the Very Large Telescope
  91. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  92. GRB 050509a: Swift-BAT refined analysis
  93. GRB 050509B: WSRT Radio Observations
  94. GRB 050505: SARA Observations
  95. Swift UVOT Follow-up Observations of GRB 050509B
  96. GRB 050509B, Optical Observations
  97. GRB 050509B: Swift/XRT refined analysis
  98. GRB050509a: Swift UVOT observations
  99. GRB 050509b: Optical observations
  100. GRB 050509b: Possible Optical Counterpart

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