Skip to main content
Circulars over Kafka event name backfill. See news and announcements

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"

18399 results found.

  1. GRB050712: Swift UVOT Observation of Afterglow Emission
  2. GRB 050713A XMM-Newton observation
  3. GRB050713B: Faulkes North Telescope observation
  4. RBO RI observations of GRB 050713A
  5. GRB 050713B
  6. GRB050713: Liverpool Telescope prompt observations
  7. GRB050709: Candidate X-ray Afterglow from Chandra
  8. GRB 050713, R-band observations at NOT
  9. GRB 050713: Swift detection of Bright Burst
  10. GRB 050713A: ROTSE-III Optical Limits
  11. GRB050712: XRT refined analysis
  12. GRB 050709: Swift UVOT and XRT observations
  13. GRB 050712: Swift-BAT Refined Analysis
  14. GRB050712: UVOT candidate optical counterpart
  15. GRB 050712: Swift XRT afterglow position
  16. GRB 050712: Swift detection of a weak burst
  17. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  18. GRB 050626: Swift XRT observations
  19. GRB 050701
  20. GRB 050701, optical observations
  21. GRB 050701: Refined XRT analysis
  22. Swift UVOT observations of GRB 050701
  23. GRB050701: Swift-BAT Refined analysis
  24. GRB 050701: Swift XRT afterglow position
  25. Swift trigger 143708 is really GRB 050701
  26. GRB 050525A: Swift Late-Time Decay Rate
  27. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  28. GRB 050416(a): Host Galaxy Redshift Determination
  29. Swift/UVOT observations of GRB050607
  30. GRB 050607: RAPTOR-S Early Optical Limits
  31. GRB050607: KAIT optical limits
  32. GRB 050607: MDM Observations
  33. GRB050607,optical observation
  34. GRB 050607 - XRT refined data analysis
  35. GRB050607 optical limit by "Pi of the Sky"
  36. GRB050607: Swift Detection of a long GRB
  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. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  43. Swift/BAT Detection of GRB050603
  44. GRB 050408: jet break in the XRT light curve
  45. GRB050528, XRT observations
  46. Correction to GCN Circ 3502 on GRB 050528
  47. Swift-BAT GRB 050528: a soft burst
  48. Update on Swift-BAT GRB 050528 (Trigger 130679)
  49. Possible GRB050528: no candidate from Liverpool Telescope
  50. Swift-BAT detection of possible GRB 050528
  51. GRB 050509b: refined XRT/Chandra afterglow position analysis
  52. GRB050525a: optical upper limits
  53. GRB 050525B: Swift-BAT observations
  54. GRB050525A,optical observation
  55. GRB050525: Super-LOTIS observations
  56. GRB 050525, spectral lag pseudo-redshift
  57. GRB050306: optical afterglow not confirmed
  58. GRB 050525A: BOOTES simultaneous optical observations
  59. GRB 050525A: Swift-BAT refined analysis
  60. Swift/UVOT UV and optical detections of GRB 050525
  61. Konus-Wind observation of GRB 050525
  62. GRB 050525: TAROT observations of the early afterglow
  63. INTEGRAL detection of GRB 050525
  64. GRB 050525: Optical observation
  65. GRB050525: ROTSE-III Refined Analysis
  66. GRB 050525 - Very Bright, Not Short
  67. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  68. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  69. XRF 050522: Swift XRT refined analysis
  70. Swift/UVOT observation of XRF 050522
  71. GRB 050509A: Further I-band imaging
  72. RBO Observations of GRB050522
  73. XRF 050522: Swift XRT observation
  74. GRB 050520: VLT/ULTRACAM observations
  75. Swift UVOT Observations of GRB 050520
  76. GRB 050520: Swift XRT refined analysis
  77. XRF050509C: Chandra Afterglow Detection
  78. XRF 050509c: Swift XRT Upper Limit
  79. RBO Observations of GRB050520
  80. GRB 050520: TAROT optical limit
  81. GRB 050520: Swift XRT position
  82. No Swift-BAT Lightcurves in real-time for next 3 weeks
  83. Swift-BAT trigger 122203 is not a real GRB
  84. GRB 050504: Swift XRT afterglow candidate has faded
  85. GRB 050509B: Subaru Optical Observations
  86. GRB050502b: Early Observation
  87. Refined Chandra analysis of GRB 050509b
  88. GRB050509b, SDSS pre-burst observations
  89. Chandra observation of GRB 050509b
  90. GRB 050509b: RAPTOR deep, early limits.
  91. GRB050509B: Optical/Infared observations
  92. GRB 050509b: Swift/UVOT follow-up measurements
  93. GRB 050509b Milagro GeV/TeV Observations
  94. GRB050509B: Optical observations at the Very Large Telescope
  95. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  96. GRB 050509a: Swift-BAT refined analysis
  97. GRB 050509B: WSRT Radio Observations
  98. GRB 050505: SARA Observations
  99. Swift UVOT Follow-up Observations of GRB 050509B
  100. GRB 050509B, Optical Observations

Advanced

Download all Circulars as a .tar.gz archive:
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov