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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"

18400 results found.

  1. GRB 050713A : Swift-BAT Refined Analysis
  2. GRB050712: Swift UVOT Observation of Afterglow Emission
  3. GRB 050713A XMM-Newton observation
  4. GRB050713B: Faulkes North Telescope observation
  5. RBO RI observations of GRB 050713A
  6. GRB 050713B
  7. GRB050713: Liverpool Telescope prompt observations
  8. GRB050709: Candidate X-ray Afterglow from Chandra
  9. GRB 050713, R-band observations at NOT
  10. GRB 050713: Swift detection of Bright Burst
  11. GRB 050713A: ROTSE-III Optical Limits
  12. GRB050712: XRT refined analysis
  13. GRB 050709: Swift UVOT and XRT observations
  14. GRB 050712: Swift-BAT Refined Analysis
  15. GRB050712: UVOT candidate optical counterpart
  16. GRB 050712: Swift XRT afterglow position
  17. GRB 050712: Swift detection of a weak burst
  18. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  19. GRB 050626: Swift XRT observations
  20. GRB 050701
  21. GRB 050701, optical observations
  22. GRB 050701: Refined XRT analysis
  23. Swift UVOT observations of GRB 050701
  24. GRB050701: Swift-BAT Refined analysis
  25. GRB 050701: Swift XRT afterglow position
  26. Swift trigger 143708 is really GRB 050701
  27. GRB 050525A: Swift Late-Time Decay Rate
  28. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  29. GRB 050416(a): Host Galaxy Redshift Determination
  30. Swift/UVOT observations of GRB050607
  31. GRB 050607: RAPTOR-S Early Optical Limits
  32. GRB050607: KAIT optical limits
  33. GRB 050607: MDM Observations
  34. GRB050607,optical observation
  35. GRB 050607 - XRT refined data analysis
  36. GRB050607 optical limit by "Pi of the Sky"
  37. GRB050607: Swift Detection of a long GRB
  38. GRB 050603 - XRT data analysis of the first day
  39. Konus-Wind observation of GRB 050603
  40. GRB 050603: Analysis of UVOT data
  41. GRB050603: Fading Afterglow observed by Swift UVOT
  42. GRB 050603: Swift XRT Position
  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 050525A: BOOTES simultaneous optical observations
  60. GRB 050525A: Swift-BAT refined analysis
  61. Swift/UVOT UV and optical detections of GRB 050525
  62. Konus-Wind observation of GRB 050525
  63. GRB 050525: TAROT observations of the early afterglow
  64. INTEGRAL detection of GRB 050525
  65. GRB 050525: Optical observation
  66. GRB050525: ROTSE-III Refined Analysis
  67. GRB 050525 - Very Bright, Not Short
  68. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  69. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  70. XRF 050522: Swift XRT refined analysis
  71. Swift/UVOT observation of XRF 050522
  72. GRB 050509A: Further I-band imaging
  73. RBO Observations of GRB050522
  74. XRF 050522: Swift XRT observation
  75. GRB 050520: VLT/ULTRACAM observations
  76. Swift UVOT Observations of GRB 050520
  77. GRB 050520: Swift XRT refined analysis
  78. XRF050509C: Chandra Afterglow Detection
  79. XRF 050509c: Swift XRT Upper Limit
  80. RBO Observations of GRB050520
  81. GRB 050520: TAROT optical limit
  82. GRB 050520: Swift XRT position
  83. No Swift-BAT Lightcurves in real-time for next 3 weeks
  84. Swift-BAT trigger 122203 is not a real GRB
  85. GRB 050504: Swift XRT afterglow candidate has faded
  86. GRB 050509B: Subaru Optical Observations
  87. GRB050502b: Early Observation
  88. Refined Chandra analysis of GRB 050509b
  89. GRB050509b, SDSS pre-burst observations
  90. Chandra observation of GRB 050509b
  91. GRB 050509b: RAPTOR deep, early limits.
  92. GRB050509B: Optical/Infared observations
  93. GRB 050509b: Swift/UVOT follow-up measurements
  94. GRB 050509b Milagro GeV/TeV Observations
  95. GRB050509B: Optical observations at the Very Large Telescope
  96. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  97. GRB 050509a: Swift-BAT refined analysis
  98. GRB 050509B: WSRT Radio Observations
  99. GRB 050505: SARA Observations
  100. Swift UVOT Follow-up Observations of GRB 050509B

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