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"

39404 results found.

  1. Konus-Wind detection of GRB 230308A
  2. Konus-Wind detection of GRB 230304B
  3. GRB 230322B: Swift-XRT refined Analysis
  4. GRB 230322B: Enhanced Swift-XRT position
  5. Swift GRB 230322B: Global MASTER-Net observations report
  6. GRB 230322B: Swift detection of a burst with optical counterpart
  7. GRB 230322A: Fermi GBM Final Real-time Localization
  8. GRB 230320B: GRBAlpha detection
  9. GRB 230321A: CALET Gamma-Ray Burst Monitor detection
  10. GRB 230320B: CALET Gamma-Ray Burst Monitor detection
  11. Fermi trigger No 701071944: Global MASTER-Net observations report
  12. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  13. Fermi GRB 230320A: Global MASTER-Net observations report
  14. Fermi GRB 230321A: Global MASTER-Net observations report
  15. Fermi trigger No 701058254: Global MASTER-Net observations report
  16. GRB 230321B: AstroSat CZTI detection
  17. GRB 230320B: AstroSat CZTI detection
  18. GRB 230321A: BALROG localization (Fermi Trigger 701065308 / GRB 230321182)
  19. GRB 230321A: Fermi GBM Final Real-time Localization
  20. GRB 230320A: Fermi GBM Final Real-time Localization
  21. GRB 230314A: TURBO Optical Upper Limit
  22. Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
  23. Fermi trigger No 700976129: Global MASTER-Net observations report
  24. GRB 230307A: Continued Gemini-South observations confirm rapid optical fading
  25. IPN triangulation of GRB 230309A
  26. Fermi GRB 230316A: Global MASTER-Net observations report
  27. GRB 230304D: AstroSat CZTI detection
  28. GRB 230316A: Fermi GBM Final Real-time Localization
  29. IPN triangulation of GRB 230304B
  30. GRB 230313A: AstroSat CZTI detection
  31. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  32. IPN triangulation of GRB 230308A (short/bright)
  33. Fermi GRB 230314A: Global MASTER-Net observations report
  34. GRB 230307A: ATCA radio detection
  35. GRB 230314A: Fermi GBM Final Real-time Localization
  36. VZLUSAT-2 detection of SGR 1806-20
  37. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  38. GRB 230307A: Swift/UVOT detection
  39. GRB 230313A: BALROG localization (Fermi Trigger 700400328 / GRB 230313485)
  40. Fermi GRB 230313A: Global MASTER-Net observations report
  41. GRB 230313A: Fermi GBM Final Real-time Localization
  42. GRB 230307A: soft X-ray detection with LEIA
  43. GRB 230307A: Swift-XRT afterglow detection
  44. GRB 230309A: AstroSat CZTI detection of a bright long GRB
  45. Swift GRB230311.85: Global MASTER-Net observations report
  46. Swift GRB230311.83: Global MASTER-Net observations report
  47. Further improved IPN localization for GRB 230307A
  48. Swift GRB230311.81: Global MASTER-Net observations report
  49. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  50. Swift GRB230311.84: Global MASTER-Net observations report
  51. Swift GRB230311.82: Global MASTER-Net observations report
  52. TESS Detection of the Optical Afterglow of GRB230307A
  53. GRB 230308A: CALET Gamma-Ray Burst Monitor detection
  54. Trigger 1159327: Swift detection of SGR1806-20
  55. GRB 230310A: AstroSat CZTI detection
  56. GRB 230307A: GECKO optical observations and detections of the afterglow
  57. GRB 230307A: MAXI/GSC upper limit
  58. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  59. Fermi GRB 230310A: Global MASTER-Net observations report
  60. GRB 230310A: Fermi GBM Final Real-time Localization
  61. GRB 230307A: AGILE/MCAL analysis
  62. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  63. GRB 230307A: Erratum of the GCN 33441
  64. GRB 230204B: MASTER detection of an object near NTT Optical Afterglow Candidate
  65. GRB 230308A: Fermi GBM detection
  66. GRB 230307A: Possible optical afterglow
  67. GRB 230307A: ASO-S/HXI detection
  68. GRB 230307A: AstroSat LAXPC detection
  69. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  70. GRB 230308A: AGILE/MCAL detection
  71. GRB 230307A: optical upper limit
  72. GRB 230217A: ATCA rapid-response radio detection
  73. Swift Trigger 1159108 is not a GRB
  74. GRB 230307A: Swift/BAT upper limits on the early afterglow
  75. GRB 230307A: Upper limits from a neutrino search with IceCube
  76. GRB 230307A: Swift-XRT observations
  77. Fermi GRB 230307A: Global MASTER-Net observations report
  78. Konus-Wind detection of GRB 230307A
  79. GRB 230228A: VIRT Optical Upper Limit
  80. Improved IPN localization for GRB 230307A
  81. GRB 230307A: VZLUSAT-2 detection
  82. GRB 230304B: CALET Gamma-Ray Burst Monitor detection
  83. Fermi GRB 230308A: Global MASTER-Net observations report
  84. GRB 230308A: BALROG localization (Fermi Trigger 699975152 / GRB 230308564)
  85. GRB 230308A: Fermi GBM Final Real-time Localization
  86. GRB 230307A: Tiled Swift observations
  87. GRB 230307A: Detection by GRBAlpha
  88. GRB 230305A: Detection by GRBAlpha
  89. GRB 230307A: BALROG localization (Fermi Trigger 699896651/ GRB 230307656)
  90. GRB 230307A: AstroSat CZTI detection
  91. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  92. IPN triangulation of GRB 230307A (long/very bright)
  93. GRB 230307A: AGILE/MCAL detection
  94. GRB 230307A: Fermi GBM Observation of a very bright burst
  95. Solar Orbiter STIX observation of GRB 230307A
  96. Fermi-LAT gamma-ray observations of IceCube-230306A
  97. GRB 230307A: Fermi GBM detection of a very bright GRB
  98. GRB 230307A: GECAM detection of an extremely bright burst
  99. GRB 230307A: Fermi GBM Final Real-time Localization
  100. Fermi trigger No 699811746: Global MASTER-Net observations report

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