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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"

18511 results found.

  1. GRB 050714B: refined XRT analysis
  2. GRB050714B: Refined analysis of the Swift-BAT burst
  3. Swift detection of a long transient (GRB 050714B?)
  4. GRB 050714: Swift XRT afterglow position
  5. GRB 050713A: XRT refined analysis
  6. GRB 050713A: RAPTOR detection of early optical emission
  7. GRB050713B :Swift/UVOT observations
  8. GRB050713b: XRT refined analysis
  9. GRB 050713B: Swift-BAT Refined Analysis
  10. Swift-BAT Trigger 145729 is not a GRB
  11. GRB 050713A: Swift/UVOT observation
  12. GRB 050713A : Swift-BAT Refined Analysis
  13. GRB050712: Swift UVOT Observation of Afterglow Emission
  14. GRB 050713A XMM-Newton observation
  15. GRB050713B: Faulkes North Telescope observation
  16. RBO RI observations of GRB 050713A
  17. GRB 050713B
  18. GRB050713: Liverpool Telescope prompt observations
  19. GRB050709: Candidate X-ray Afterglow from Chandra
  20. GRB 050713, R-band observations at NOT
  21. GRB 050713: Swift detection of Bright Burst
  22. GRB 050713A: ROTSE-III Optical Limits
  23. GRB050712: XRT refined analysis
  24. GRB 050709: Swift UVOT and XRT observations
  25. GRB 050712: Swift-BAT Refined Analysis
  26. GRB050712: UVOT candidate optical counterpart
  27. GRB 050712: Swift XRT afterglow position
  28. GRB 050712: Swift detection of a weak burst
  29. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  30. GRB 050626: Swift XRT observations
  31. GRB 050701
  32. GRB 050701, optical observations
  33. GRB 050701: Refined XRT analysis
  34. Swift UVOT observations of GRB 050701
  35. GRB050701: Swift-BAT Refined analysis
  36. GRB 050701: Swift XRT afterglow position
  37. Swift trigger 143708 is really GRB 050701
  38. GRB 050525A: Swift Late-Time Decay Rate
  39. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  40. GRB 050416(a): Host Galaxy Redshift Determination
  41. Swift/UVOT observations of GRB050607
  42. GRB 050607: RAPTOR-S Early Optical Limits
  43. GRB050607: KAIT optical limits
  44. GRB 050607: MDM Observations
  45. GRB050607,optical observation
  46. GRB 050607 - XRT refined data analysis
  47. GRB050607 optical limit by "Pi of the Sky"
  48. GRB050607: Swift Detection of a long GRB
  49. GRB 050603 - XRT data analysis of the first day
  50. Konus-Wind observation of GRB 050603
  51. GRB 050603: Analysis of UVOT data
  52. GRB050603: Fading Afterglow observed by Swift UVOT
  53. GRB 050603: Swift XRT Position
  54. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  55. Swift/BAT Detection of GRB050603
  56. GRB 050408: jet break in the XRT light curve
  57. GRB050528, XRT observations
  58. Correction to GCN Circ 3502 on GRB 050528
  59. Swift-BAT GRB 050528: a soft burst
  60. Update on Swift-BAT GRB 050528 (Trigger 130679)
  61. Possible GRB050528: no candidate from Liverpool Telescope
  62. Swift-BAT detection of possible GRB 050528
  63. GRB 050509b: refined XRT/Chandra afterglow position analysis
  64. GRB050525a: optical upper limits
  65. GRB 050525B: Swift-BAT observations
  66. GRB050525A,optical observation
  67. GRB050525: Super-LOTIS observations
  68. GRB 050525, spectral lag pseudo-redshift
  69. GRB050306: optical afterglow not confirmed
  70. GRB 050525A: BOOTES simultaneous optical observations
  71. GRB 050525A: Swift-BAT refined analysis
  72. Swift/UVOT UV and optical detections of GRB 050525
  73. Konus-Wind observation of GRB 050525
  74. GRB 050525: TAROT observations of the early afterglow
  75. INTEGRAL detection of GRB 050525
  76. GRB 050525: Optical observation
  77. GRB050525: ROTSE-III Refined Analysis
  78. GRB 050525 - Very Bright, Not Short
  79. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  80. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  81. XRF 050522: Swift XRT refined analysis
  82. Swift/UVOT observation of XRF 050522
  83. GRB 050509A: Further I-band imaging
  84. RBO Observations of GRB050522
  85. XRF 050522: Swift XRT observation
  86. GRB 050520: VLT/ULTRACAM observations
  87. Swift UVOT Observations of GRB 050520
  88. GRB 050520: Swift XRT refined analysis
  89. XRF050509C: Chandra Afterglow Detection
  90. XRF 050509c: Swift XRT Upper Limit
  91. RBO Observations of GRB050520
  92. GRB 050520: TAROT optical limit
  93. GRB 050520: Swift XRT position
  94. No Swift-BAT Lightcurves in real-time for next 3 weeks
  95. Swift-BAT trigger 122203 is not a real GRB
  96. GRB 050504: Swift XRT afterglow candidate has faded
  97. GRB 050509B: Subaru Optical Observations
  98. GRB050502b: Early Observation
  99. Refined Chandra analysis of GRB 050509b
  100. GRB050509b, SDSS pre-burst observations

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