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"

24539 results found.

  1. GRB231115A: GRANDMA Observations
  2. GRB 231115A: Non-detection in low-latency of gravitational waves with LIGO/Virgo/KAGRA
  3. GRB 231115A: pre-burst ZTF upper limits for GRB optical counterpart candidate
  4. GRB 231106A: TESS identification of candidate optical counterpart
  5. GRB 231115A: MASTER optical observations
  6. GRB 231115A: Fermi Observations of a probable Magnetar Giant Flare from M82
  7. Integral GRB231115.65: Global MASTER-Net observations report
  8. Fermi GRB 231115A: Global MASTER-Net observations report
  9. GRB 231115A: significance of INTEGRAL localization alignment with M82
  10. GRB 231115A: Fermi GBM Final Real-time Localization
  11. LIGO/Virgo/KAGRA S231113bw: Updated Sky localization, EM Bright Classification, and Source Classification
  12. GRB 231111A: Swift-BAT refined analysis
  13. LIGO/Virgo/KAGRA S231113bw: Zwicky Transient Facility observations
  14. LIGO/Virgo/KAGRA S231114n: Updated Sky localization
  15. Fermi GRB 231114A: Global MASTER-Net observations report
  16. GRB 231113A (short): Glowbug gamma-ray detection
  17. GECAM-B observation of a short burst from SGR J1555-5402
  18. GRB 231114A: Fermi GBM Final Localization
  19. LIGO/Virgo S231113bw: upper limits from AGILE/MCAL
  20. LIGO/Virgo/KAGRA S231114n: Identification of a GW compact binary merger candidate
  21. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  22. LIGO/Virgo/KAGRA S231113bw: Upper limits from Fermi-GBM Observations
  23. GRB 231110A: CALET Gamma-Ray Burst Monitor detection
  24. LIGO/Virgo/KAGRA S231113cd: Coverage and upper limits from MAXI/GSC observations
  25. LIGO/Virgo/KAGRA S231113bb: Updated Sky localization
  26. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  27. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate
  28. GRB 231110A: Swift-BAT refined analysis
  29. LIGO/Virgo/KAGRA S231113bb: Identification of a GW compact binary merger candidate
  30. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  31. GRB 231104A: VZLUSAT-2 detection
  32. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  33. GRB231111A: Optical follow-up observations with Mephisto
  34. GRB 231106B: GRBAlpha detection
  35. GRB 231111A: Swift-XRT refined Analysis
  36. GRB 231111A: GECAM-C detection of a long burst (correction)
  37. GRB 231110A: GECAM-B detection (correction)
  38. GRB 231111A: GECAM-C detection of a long burst
  39. GRB 231110A: GECAM detection
  40. GRB 231110A: Swift-XRT afterglow detection
  41. GRB 231111A: MASTER OT earlier detection
  42. Swift GRB231111.60: Global MASTER-Net observations report
  43. Swift GRB231110.89: Global MASTER-Net observations report
  44. GRB 231110A: Swift detection of a burst
  45. LIGO/Virgo/KAGRA S231110g: Updated Sky localization
  46. LIGO/Virgo/KAGRA S231110g: Identification of a GW compact binary merger candidate
  47. GRB 231109A: Fermi GBM Final Localization
  48. IceCube-231103A: No candidates from the Zwicky Transient Facility
  49. LIGO/Virgo/KAGRA S231108u: Updated Sky localization
  50. Fermi trigger No 721204446: Global MASTER-Net observations report
  51. Fermi GRB 231108A: Global MASTER-Net observations report
  52. GRB 231108A: Fermi GBM Final Real-time Localization
  53. LIGO/Virgo/KAGRA O4 Landscape
  54. LIGO/Virgo/KAGRA S231108u: Identification of a GW compact binary merger candidate
  55. GRB 231106A: CALET Gamma-Ray Burst Monitor detection
  56. GRB 231104A: Swift-BAT refined analysis
  57. Fermi trigger No 721006392: Global MASTER-Net observations report
  58. GRB 231104A: FRAM-ORM optical limit
  59. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  60. Fermi GRB 231106A: Global MASTER-Net observations report
  61. GRB 231104A: NuSTAR Observation of the prompt emission
  62. GRB 231106A: Fermi GBM Final Real-time Localization
  63. GRB 231104A: 3.6m DOT optical upper limit
  64. IceCube-231103A: Upper limits from a search for additional neutrino events in IceCube
  65. LIGO/Virgo/KAGRA S231106y: one counterpart neutrino candidate from IceCube neutrino searches
  66. Fermi-LAT gamma-ray observations of IceCube-231103A
  67. GRB 231104A: Fermi GBM Observation
  68. GRB 231104B: Fermi GBM Final Real-time Localization
  69. Fermi GRB 231103A: Global MASTER-Net observations report
  70. LIGO/Virgo/KAGRA S231104ac: Updated Sky localization
  71. GRB 231104A: AKO Upper Limit
  72. GRB 231104A: AstroSat CZTI detection
  73. GRB 231104A: Swift-XRT refined Analysis
  74. GRB 231104A: Fermi-LAT detection
  75. LIGO/Virgo/KAGRA S231104ac: Identification of a GW compact binary merger candidate
  76. GRB231104A: LCOGT Optical Upper Limits
  77. GRB 231104A: Fermi GBM Final Real-time Localization
  78. Swift GRB231104.07: Global MASTER-Net observations report
  79. IceCube Alert 231103.39: Global MASTER-Net observations report
  80. GRB 231103A: Fermi GBM Final Real-time Localization
  81. IceCube-231103A - IceCube observation of a high-energy neutrino candidate track-like event
  82. Fermi-LAT gamma-ray observations of IceCube-231027A
  83. LIGO/Virgo/KAGRA S231102w: Updated Sky localization
  84. LIGO/Virgo/KAGRA S231102i: Global MASTER-Net observations report
  85. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  86. LIGO/Virgo/KAGRA S231102w: Identification of a GW compact binary merger candidate
  87. New Swift-BAT/GUANO and IceCube Notices Available via GCN Kafka
  88. Fermi trigger No 720498201: Global MASTER-Net observations report
  89. GRB 231101A: Fermi GBM Final Real-time Localization
  90. GRB 231030B: GRBAlpha detection
  91. GRB 231028B: VZLUSAT-2 detection
  92. Fermi trigger No 720415645: Global MASTER-Net observations report
  93. GRB 231030B: Fermi GBM Detection
  94. Fermi GRB 231030B: Global MASTER-Net observations report
  95. IPN triangulation of GRB 231020A
  96. GRB 231030B: BALROG localization (Fermi Trigger 720388704 / GRB 231030832)
  97. GRB 231030B: Fermi GBM Final Real-time Localization
  98. GRB 231028A: Swift-BAT refined analysis
  99. IceCube-231027A: Upper limits from a search for additional neutrino events in IceCube
  100. LIGO/Virgo/KAGRA S231029y: 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