Skip to main content
GCN at AAS 245, Legacy Circulars Address Retirement. 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').

18035 results found.

  1. VLA IInd observation of INTEGRAL burst GRB 071109
  2. Swift/UVOT initial analysis of GRB071109
  3. GRB 071109: further Swift-XRT analysis
  4. No radio detection at Swift-XRT position
  5. GRB 071109: Swift-XRT possible X-ray counterpart
  6. GRB 071104: Swift-XRT Team Refined Analysis
  7. GRB 071104: Possible Swift UVOT Afterglow Candidate
  8. GRB 071104: Swift-XRT position
  9. Swift XRT and UVOT observations of GRB071028B
  10. GRB 071101, Swift-BAT refined analysis
  11. GRB 071101: Swift-XRT Team refined analysis
  12. GRB 071101: TAROT Calern observatory optical observations
  13. GRB 071101: Swift XRT position
  14. GRB 071101: BOOTES-2 prompt optical observations
  15. GRB 071101: a nearby galaxy
  16. GRB 071101: Swift detection of a burst
  17. GRB 071031, Swift-BAT refined analysis
  18. GRB 071031: Swift/UVOT detection of afterglow
  19. GRB 071031: Swift-XRT Team refined analysis
  20. GRB 071031: Swift detection of a burst with an optical counterpart
  21. GRB 071028B Swift-BAT detection of a burst
  22. Swift UVOT upper limits to GRB071028
  23. GRB 071028: Swift-XRT Team refined analysis
  24. GRB 071028, Swift-BAT refined analysis
  25. GRB 071028: Swift detection of a burst
  26. GRB 071025: Kuiper Telescope Optical Observations
  27. GRB 071018: Revised BAT position
  28. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  29. GRB071021: MARGE Optical Limits
  30. GRB071020, optical upper limit
  31. GRB 071025 Milagro GeV/TeV Observations
  32. Swift UVOT upper limits
  33. GRB 071025: Swift-XRT Team refined analysis
  34. GRB 071025, Swift-BAT refined analysis
  35. GRB 071025: Early Super-LOTIS Observations
  36. GRB 071025: ROTSE-III Refined Analysis
  37. GRB 071025: Swift XRT refined position
  38. GRB 071025: ROTSE-III Detection of Optical Counterpart
  39. GRB 071025: Swift detection of a burst
  40. GRB 071020: BTA spectroscopy
  41. Possible radio detection of GRB 071021 with the VLA
  42. Radio detection of GRB 071020 with the VLA
  43. GRB 071021: optical and NIR observations
  44. GRB 071021, Swift-BAT refined analysis
  45. GRB 071021: Swift-XRT Team refined analysis
  46. Konus-Wind observation of GRB 071020
  47. GRB 071021: Swift detection of a burst
  48. GRB 071020: Swift-XRT refined analysis
  49. GRB 071020, Swift-BAT refined analysis
  50. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  51. GRB071020 - SDSS Pre-burst Observations
  52. GRB 071020: Swift detection of a bright burst
  53. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  54. GRB 071018: Mercator Telescope optical observations
  55. Swift autonomous slewing re-enabled
  56. GRB 071018: Swift-XRT observation
  57. GRB 071017 - Swift XRT observations
  58. VLA radio observation of GRB 071018
  59. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  60. GRB 071018, Swift-BAT refined analysis
  61. GRB 071018?: Swift detection of a possible burst
  62. GRB 071010B: Suzaku WAM observation of the prompt emission
  63. GRB 071013: 3rd TLS Epoch - constraints on variability
  64. GRB 071013: TLS Upper Limit
  65. VLA detection of radio afterglow of GRB 071010B
  66. VLA non-detection of GRB 071011
  67. GRB 071013: Optical observations
  68. GRB 071013, Swift-BAT refined analysis
  69. GRB 071013: Swift detection of a burst
  70. GRB 071010C Swift-BAT detection of a burst
  71. GRB 071011: Swift-XRT refined analysis
  72. VLA non-detection of GRB 071010A
  73. GRB 071011, Optical afterglow
  74. GRB 071011: MARGE Optical Limits
  75. GRB 071011: XRT afterglow detection
  76. GRB 071011, Swift-BAT refined analysis
  77. GRB 071011: Early Super-LOTIS Observations
  78. GRB 071010B: Bright OT confirmed with TLS
  79. GRB 071011: Swift detection of a burst
  80. Optical Observation: GRB 071010
  81. Optical observations: GRB 071010A
  82. Konus-Wind observation of GRB 071010B
  83. GRB071010B: Swift/XRT detection
  84. GRB 071010B, Swift-BAT refined analysis
  85. GRB 071006, Swift-BAT refined analysis
  86. GRB 071010B: Swift detection of a burst
  87. GRB 071010: Swift-XRT observation
  88. GRB 071008, Swift-BAT refined analysis
  89. GRB 071010, Swift-BAT refined analysis
  90. GRB071008: Swift-XRT observation
  91. GRB 071010: TAROT La Silla observatory detection of the afterglow
  92. GRB 071010: Swift detection of a burst
  93. GRB 071006 Swift-BAT detection of a burst
  94. GRB071008: IAC80 observation
  95. GRB 071008: Swift detection of a burst
  96. GRB 071003: XRT refined analysis
  97. GRB070920A: MAGIC telescope GeV observation
  98. Radio detection of GRB 071003 with the VLA
  99. GRB 070810B: further XRT analysis
  100. Konus-Wind observation of GRB 071003

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