Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

19662 results found.

  1. GRB 231230A: Swift detection of a burst
  2. Swift GRB231230.06: Global MASTER-Net observations report
  3. GRB 231210B: BOOTES-7 optical upper limit
  4. Swift Triggers 1205103, 1205104, 1205107 and 1205110 are not astrophysical events
  5. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  6. GRB 231222B: Swift-XRT afterglow detection
  7. GRB 231222B: Fermi-LAT detection
  8. GRB 231222A: Tiled Swift observations
  9. GRID detection of GRB 231215A
  10. GRB 231220A: Swift-XRT follow-up observations
  11. GRB 231220A: Swift ToO observations
  12. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  13. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  14. GRID detection of GRB 231205B
  15. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  16. GRB 231214B: Fermi GBM observation
  17. GRB 231216A: 10.4 m GTC optical upper limit
  18. GRB 231216A: Nanshan/HMT optical upper limit
  19. GRB 231216A: LCOGT Optical Upper Limits
  20. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  21. GRB 231216A: Swift-XRT refined analysis correction
  22. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  23. GRB 231216A: Swift-XRT refined Analysis
  24. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  25. GRB 231216A: REM NIR upper limits
  26. GRB 231216A: Swift/UVOT Upper Limits
  27. GRB 231216A: Swift-BAT refined analysis
  28. GRB 231215A: Swift-BAT refined analysis
  29. GRB 231214A: Swift-BAT refined analysis
  30. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  31. GRB 231216A: GIT optical upper limit
  32. GRB 231216A: BOOTES-2/TELMA optical upper limit
  33. GRB 231215A: GRBAlpha detection
  34. Swift GRB231216.77: Global MASTER-Net observations report
  35. GRB 231216A: Swift detection of a burst
  36. Konus-Wind detection of GRB 231215A
  37. GRB 231215A: NOT optical observations
  38. GRB 231214A: Swift/UVOT Upper Limits
  39. GRB 231205B: VZLUSAT-2 detection
  40. GRB 231215A: Fermi GBM observation
  41. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  42. GRB 231215A: Swift/UVOT Detection
  43. GRB 231215A: Swift-XRT refined Analysis
  44. GRB 231215A: BOOTES-4/MET optical detection
  45. GRB 231215A: AKO Optical Upper Limit
  46. GRB 231215A: AGILE detection
  47. GRB 231214A: Fermi GBM observation
  48. Konus-Wind detection of GRB 231210B
  49. GRB 231215A: Enhanced Swift-XRT position
  50. GRB 231214A: REM optical/NIR upper limits
  51. GRB 231215A: GROWTH-India optical follow-up
  52. GRB 231215A : Nanshan/HMT optical observations
  53. GRB 231215A: AstroSat CZTI detection
  54. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  55. GRB 231214A: Swift-XRT refined Analysis
  56. GRB 231215A: Mondy optical bright afterglow detection
  57. GRB 231214A: AstroSat CZTI detection
  58. GRB 231215C: MASTER OT detection
  59. Swift GRB231215.41: Global MASTER-Net observations report
  60. GRB 231215A: Swift-XRT observations
  61. GRB 231215A: Swift detection of a burst
  62. GRB 231214A: Fermi-LAT detection
  63. GRB 231214A: Enhanced Swift-XRT position
  64. GRB 231214B: Swift/BAT-GUANO detection of a burst
  65. GRB231214A: BOOTES-6/DPRT optical upper limit
  66. Swift GRB231214.85: Global MASTER-Net observations report
  67. GRB 231214A: Swift detection of a burst
  68. GRB 231210B: REM optical/NIR upper limits
  69. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  70. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  71. GRB 231210B: MeerLICHT afterglow observations
  72. GRB 231210B: Swift-BAT refined analysis
  73. GRB 231210B: Swift-XRT refined Analysis
  74. GRB 231210B: Enhanced Swift-XRT position
  75. GRB 231210B: VLT/X-shooter redshift
  76. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  77. GRB 231210B: Swift detection of a burst with optical counterpart
  78. Swift GRB231210.90: Global MASTER-Net OT detection
  79. Swift GRB231210.90: Global MASTER-Net observations report
  80. IPN triangulation of GRB 231129C
  81. GRB231205B: Swift/UVOT Upper Limits
  82. GRB 231205B: Swift-BAT refined analysis
  83. GRB 231205B: 1.3m DFOT Optical upper limit
  84. GRB 231205B: AGILE detection
  85. GRB 231205B: Ondrejov D50 optical upper limit
  86. GRB 231205B: Swift-XRT refined Analysis
  87. GRB 231205B: REM optical/NIR upper limits
  88. GRB 231129C: ASIM MXGS observation and localization
  89. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  90. GRB 231205B : MITSuME Akeno optical upper limits
  91. GRB 231205B: Zadko observatory - Gingin optical observations
  92. GRB 231205B: Gaoyazi/GOT optical upper limit
  93. GRB 231205B: Nanshan/HMT optical upper limit
  94. GRB 231205B: GECAM-B detection of a long burst
  95. GRB 231205B: LCOGT Optical Upper Limits
  96. GRB 231205B: Enhanced Swift-XRT position
  97. Swift GRB231205.70: Global MASTER-Net observations report
  98. GRB 231205B: AKO Optical Upper Limit
  99. GRB 231205B: Swift detection of a burst
  100. LIGO/Virgo/KAGRA S231129ac: Upper limits from Swift/BAT-GUANO

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