Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

42177 results found.

  1. GRB 050626: Swift XRT observations
  2. GRB 050701, optical observations
  3. Swift UVOT observations of GRB 050701
  4. GRB050701: Swift-BAT Refined analysis
  5. GRB 050701: Swift XRT afterglow position
  6. Swift trigger 143708 is really GRB 050701
  7. GRB 050607, radio observations
  8. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  9. GRB 050626 - a long GRB detected with INTEGRAL
  10. GRB 050525A: Swift Late-Time Decay Rate
  11. GRB050525a: HST Observations
  12. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  13. H3804: A Possible New XRB Detected by HETE
  14. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  15. XRF 050509c: Optical monitoring
  16. Konus-Wind observation of an intermediate burst from SGR 1806-20
  17. XRF050509c: Radio Detection
  18. GRB 050416(a): Host Galaxy Redshift Determination
  19. GRB 050607: MDM Observation
  20. GRB 050607 optical decay
  21. GRB 050607: RTT150 optical observations
  22. GRB050607: refined analysis of prompt REM observations
  23. Swift/UVOT observations of GRB050607
  24. GRB 050607 : Lulin R-band observation
  25. GRB 050607: PROMPT VRcIc Observations
  26. GRB 050607: RAPTOR-S Early Optical Limits
  27. GRB050607: KAIT optical limits
  28. GRB 050525a, Mid-Infrared Observations
  29. GRB 050607: Optical decay and spectral slope
  30. GRB 050607: MDM Observations
  31. GRB050607,optical observation
  32. GRB 050607 - XRT refined data analysis
  33. Optical Afterglow of GRB 050607
  34. GRB050607 optical limit by "Pi of the Sky"
  35. GRB050607: Swift Detection of a long GRB
  36. GRB050607: P60 Observations
  37. GRB050607: prompt REM observations
  38. GRB 050603: prediction of t_break
  39. Limits on a SN in the field of GRB 050509b
  40. GRB 050603: Redshift
  41. GRB 050603 - XRT data analysis of the first day
  42. GRB050603: Fading Afterglow observed by Swift UVOT
  43. GRB050603, submillimetre observations
  44. GRB 050603: Swift XRT Position
  45. GRB050603: Radio Detection
  46. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  47. GRB 050603: Afterglow Identification from LCO
  48. GRB 050603: INTEGRAL shows it is not a short GRB
  49. Swift/BAT Detection of GRB050603
  50. GRB 050408: jet break in the XRT light curve
  51. GRB 050525a, infrared observations
  52. GRB 050525a, SMARTS optical/IR afterglow observations
  53. GRB050528, XRT observations
  54. Swift-BAT GRB 050528: a soft burst
  55. Update on Swift-BAT GRB 050528 (Trigger 130679)
  56. GRB050528: BOOTES optical candidate (retraction)
  57. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  58. GRB050528: BOOTES optical candidate
  59. Swift-BAT detection of possible GRB 050528
  60. GRB050525a: Radio Observations
  61. GRB 050509b: refined XRT/Chandra afterglow position analysis
  62. GRB 050525: RTT150, Optical observations
  63. GRB050525a: optical upper limits
  64. GRB 050525a: SARA Observations
  65. GRB 050525B: Swift-BAT observations
  66. GRB 050525: MITSuME Optical Observation in VRI
  67. GRB 050525a: MDM Observations
  68. GRB050525A,optical observation
  69. GRB 050525 : Lulin optical afterglow observations
  70. GRB050525: Super-LOTIS observations
  71. GRB 050525, spectral lag pseudo-redshift
  72. GRB 050525a: Gemini/GMOS Spectra
  73. GRB050306: optical afterglow not confirmed
  74. GRB 050525: BART optical observation
  75. GRB 050525A: BOOTES simultaneous optical observations
  76. GRB 050525A: Swift-BAT refined analysis
  77. GRB050525: Optical observations
  78. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  79. Swift/UVOT UV and optical detections of GRB 050525
  80. Konus-Wind observation of GRB 050525
  81. GRB 050525: TAROT observations of the early afterglow
  82. INTEGRAL detection of GRB 050525
  83. GRB 050525, infrared observations
  84. GRB 050525: Optical observation
  85. GRB 050525: observatons of the optical afterglow
  86. GRB050525: ROTSE-III Refined Analysis
  87. GRB 050525 - Very Bright, Not Short
  88. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  89. XRF 050522: Swift XRT refined analysis
  90. GRB 050509A: Further I-band imaging
  91. GRB050522,optical observation
  92. GRB050520,optical observation
  93. XRF 050522: Continued NIR P200 Monitoring
  94. RBO Observations of GRB050522
  95. GRB050509b: optical observations
  96. Recent GRB BVRcIc field photometry
  97. XRF 050522: Swift XRT observation
  98. XRF050522, BVRcIc field photometry
  99. XRF 050522 : Lulin observations
  100. XRF050522: Optical Observations

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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