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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"

19190 results found.

  1. GRB 050713A: ROTSE-III Optical Limits
  2. GRB050712: XRT refined analysis
  3. GRB 050709: Swift UVOT and XRT observations
  4. GRB 050712: Swift-BAT Refined Analysis
  5. GRB050712: UVOT candidate optical counterpart
  6. GRB 050712: Swift XRT afterglow position
  7. GRB 050712: Swift detection of a weak burst
  8. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  9. GRB 050626: Swift XRT observations
  10. GRB 050701
  11. GRB 050701, optical observations
  12. GRB 050701: Refined XRT analysis
  13. Swift UVOT observations of GRB 050701
  14. GRB050701: Swift-BAT Refined analysis
  15. GRB 050701: Swift XRT afterglow position
  16. Swift trigger 143708 is really GRB 050701
  17. GRB 050525A: Swift Late-Time Decay Rate
  18. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  19. GRB 050416(a): Host Galaxy Redshift Determination
  20. Swift/UVOT observations of GRB050607
  21. GRB 050607: RAPTOR-S Early Optical Limits
  22. GRB050607: KAIT optical limits
  23. GRB 050607: MDM Observations
  24. GRB050607,optical observation
  25. GRB 050607 - XRT refined data analysis
  26. GRB050607 optical limit by "Pi of the Sky"
  27. GRB050607: Swift Detection of a long GRB
  28. GRB 050603 - XRT data analysis of the first day
  29. Konus-Wind observation of GRB 050603
  30. GRB 050603: Analysis of UVOT data
  31. GRB050603: Fading Afterglow observed by Swift UVOT
  32. GRB 050603: Swift XRT Position
  33. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  34. Swift/BAT Detection of GRB050603
  35. GRB 050408: jet break in the XRT light curve
  36. GRB050528, XRT observations
  37. Correction to GCN Circ 3502 on GRB 050528
  38. Swift-BAT GRB 050528: a soft burst
  39. Update on Swift-BAT GRB 050528 (Trigger 130679)
  40. Possible GRB050528: no candidate from Liverpool Telescope
  41. Swift-BAT detection of possible GRB 050528
  42. GRB 050509b: refined XRT/Chandra afterglow position analysis
  43. GRB050525a: optical upper limits
  44. GRB 050525B: Swift-BAT observations
  45. GRB050525A,optical observation
  46. GRB050525: Super-LOTIS observations
  47. GRB 050525, spectral lag pseudo-redshift
  48. GRB050306: optical afterglow not confirmed
  49. GRB 050525A: BOOTES simultaneous optical observations
  50. GRB 050525A: Swift-BAT refined analysis
  51. Swift/UVOT UV and optical detections of GRB 050525
  52. Konus-Wind observation of GRB 050525
  53. GRB 050525: TAROT observations of the early afterglow
  54. INTEGRAL detection of GRB 050525
  55. GRB 050525: Optical observation
  56. GRB050525: ROTSE-III Refined Analysis
  57. GRB 050525 - Very Bright, Not Short
  58. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  59. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  60. XRF 050522: Swift XRT refined analysis
  61. Swift/UVOT observation of XRF 050522
  62. GRB 050509A: Further I-band imaging
  63. RBO Observations of GRB050522
  64. XRF 050522: Swift XRT observation
  65. GRB 050520: VLT/ULTRACAM observations
  66. Swift UVOT Observations of GRB 050520
  67. GRB 050520: Swift XRT refined analysis
  68. XRF050509C: Chandra Afterglow Detection
  69. XRF 050509c: Swift XRT Upper Limit
  70. RBO Observations of GRB050520
  71. GRB 050520: TAROT optical limit
  72. GRB 050520: Swift XRT position
  73. No Swift-BAT Lightcurves in real-time for next 3 weeks
  74. Swift-BAT trigger 122203 is not a real GRB
  75. GRB 050504: Swift XRT afterglow candidate has faded
  76. GRB 050509B: Subaru Optical Observations
  77. GRB050502b: Early Observation
  78. Refined Chandra analysis of GRB 050509b
  79. GRB050509b, SDSS pre-burst observations
  80. Chandra observation of GRB 050509b
  81. GRB 050509b: RAPTOR deep, early limits.
  82. GRB050509B: Optical/Infared observations
  83. GRB 050509b: Swift/UVOT follow-up measurements
  84. GRB 050509b Milagro GeV/TeV Observations
  85. GRB050509B: Optical observations at the Very Large Telescope
  86. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  87. GRB 050509a: Swift-BAT refined analysis
  88. GRB 050509B: WSRT Radio Observations
  89. GRB 050505: SARA Observations
  90. Swift UVOT Follow-up Observations of GRB 050509B
  91. GRB 050509B, Optical Observations
  92. GRB 050509B: Swift/XRT refined analysis
  93. GRB050509a: Swift UVOT observations
  94. GRB 050509b: Optical observations
  95. GRB 050509b: Possible Optical Counterpart
  96. GRB 050509A: Optical observations
  97. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  98. GRB 050509b: optical observations
  99. GRB 050509b: Swift XRT Position
  100. GRB 050509B: ROTSE-III Optical Limits

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