Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

26358 results found.

  1. GRB 050525a, infrared observations
  2. GRB050528, XRT observations
  3. GRB050528: updated Liverpool Telescope limits
  4. Swift-BAT GRB 050528: a soft burst
  5. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  6. Possible GRB050528: no candidate from Liverpool Telescope
  7. GRB050525a: Radio Observations
  8. GRB 050509b: refined XRT/Chandra afterglow position analysis
  9. GRB 050525: RTT150, Optical observations
  10. GRB 050525a: SARA Observations
  11. GRB 050525B: Swift-BAT observations
  12. GRB 050525: MITSuME Optical Observation in VRI
  13. GRB050525A,optical observation
  14. GRB050525: Super-LOTIS observations
  15. GRB 050525, spectral lag pseudo-redshift
  16. GRB050306: optical afterglow not confirmed
  17. GRB 050525: BART optical observation
  18. GRB 050525A: BOOTES simultaneous optical observations
  19. GRB 050525A: Swift-BAT refined analysis
  20. GRB050525: Optical observations
  21. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  22. Konus-Wind observation of GRB 050525
  23. GRB 050525: TAROT observations of the early afterglow
  24. INTEGRAL detection of GRB 050525
  25. GRB 050525, infrared observations
  26. GRB 050525: observatons of the optical afterglow
  27. GRB050525: ROTSE-III Refined Analysis
  28. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  29. XRF050522: Radio Observations
  30. Swift/UVOT observation of XRF 050522
  31. GRB 050509A: Further I-band imaging
  32. GRB050522,optical observation
  33. GRB050520,optical observation
  34. XRF 050522: Continued NIR P200 Monitoring
  35. RBO Observations of GRB050522
  36. Recent GRB BVRcIc field photometry
  37. GRB050520: Radio Observations
  38. XRF 050522: Swift XRT observation
  39. XRF050522, BVRcIc field photometry
  40. XRF050522: Optical Observations
  41. XRF050522: Near-infrared Observations
  42. GRB 050520: VLT/ULTRACAM observations
  43. GRB 050520: Swift XRT refined analysis
  44. XRF050509C: Chandra Afterglow Detection
  45. XRF050509c: Radio Observations
  46. GRB 050520: P200 Observations
  47. GRB 050520: TAROT optical limit
  48. GRB 050520: VLT/ULTRACAM observations
  49. XRF 050509c optical afterglow
  50. GRB 050509B and short GRB-SN association? (corrected)
  51. GRB 050509B and short GRB-SN association?
  52. GRB050502b: Early Observation
  53. GRB050509b, Bok telescope B-band imaging
  54. Refined Chandra analysis of GRB 050509b
  55. GRB050509b, SDSS pre-burst observations
  56. GRB 050509b: Keck/Chandra Cross-Correlation
  57. GRB 050509b: Keck/Chandra Cross-Correlation
  58. Chandra observation of GRB 050509b
  59. GRB 050509b: RAPTOR deep, early limits.
  60. GRB050509B: Optical observations at the Very Large Telescope
  61. GRB 050509b: No Optical Variability in XRT Error Circle
  62. GRB 050509a: Swift-BAT refined analysis
  63. GRB 050509c: ROTSE-III Optical Limits
  64. GRB 050505, early TAROT observation
  65. GRB050509c: REM NIR and Optical observations
  66. GRB 050509b: Physical Properties of the Candidate Host galaxy
  67. GRB 050505: SARA Observations
  68. GRB 050509B, Optical Observations
  69. GRB 050509B: Swift/XRT refined analysis
  70. GRB 050509b: Optical observations
  71. GRB 050509A: Optical observations
  72. GRB050509b: Radio Observations
  73. GRB 050509b: PAIRITEL and WIYN Observations
  74. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  75. Swift Detection of GRB050509b: A short duration burst
  76. Swift Detection of the Burst GRB050509
  77. GRB 050505: early time observations
  78. GRB 050505, simultaneous optical observation
  79. GRB050505: AAVSO observations
  80. GRB050416A : 1 GHz limit from GMRT
  81. GRB050505: Optical Afterglow Candidate
  82. GRB050505 Swift-BAT refined analysis
  83. GRB 050416b:Swift XRT afterglow upper limits
  84. GRB 050416b:Swift XRT afterglow upper limits
  85. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  86. GRB050502b: Afterglow Confirmation
  87. GRB050502: P200 Observations (Correction)
  88. GRB050502: P200 Observations
  89. GRB 050504 : R band observation at Lulin observatory
  90. Swift UVOT observation of GRB 050504
  91. GRB 050504, R band Observations
  92. GRB 050502b, V band Observations
  93. GRB050504: P60 Observations
  94. GRB 050504: A long GRB detected with INTEGRAL
  95. GRB (?) 050504: IR Observations, Intriguing Source
  96. GRB 050502b, Optical observations
  97. GRB050502a: P60 Observations (Correction)
  98. GRB050502a: P60 Observations
  99. Renewal of SGR 1806-20 activity
  100. GRB050502B Swift-BAT refined analysis

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