Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

2975 results found.

  1. Fermi GRB 240229A: Global MASTER-Net observations report
  2. IceCube Alert 240229.66: Global MASTER-Net observations report
  3. Fermi trigger No 730618809: Global MASTER-Net observations report
  4. GRB 240216A: Glowbug gamma-ray detection
  5. GRB 240218A: Swift-BAT refined analysis
  6. GRB 240215A: Fermi GBM Observation
  7. GRB 240216A: GRBAlpha detection
  8. Fermi trigger No 729914426: Global MASTER-Net observations report
  9. GRB 240216A: Fermi GBM Final Real-time Localization
  10. GRB 240214A/1H 0451-560: MAXI/GSC detection
  11. Fermi trigger No 729152364: Global MASTER-Net observations report
  12. Fermi trigger No 729012023: Global MASTER-Net observations report
  13. Konus-Wind detection of GRB 240205B (long / very soft)
  14. GRB 240204A: Swift-BAT refined analysis
  15. Fermi trigger No 728749569: Global MASTER-Net observations report
  16. GRB 240204a: Liverpool Telescope optical afterglow detection
  17. IceCube Alert 240123.48: Global MASTER-Net observations report
  18. Swift triggers 1209631, 1209632, 1209635 and 1209644 are not interesting astrophysical events
  19. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-240118A
  20. Swift Triggers 1209371 through 1209374 are not astrophysical events
  21. Fermi GRB 240115A: Global MASTER-Net observations report
  22. GRB 240114A: MAXI/GSC detection
  23. Fermi GRB 240112D: Global MASTER-Net observations report
  24. Konus-Wind detection of GRB 240101C
  25. GRB 231215A: radio detection with the VLA
  26. Swift GRB240109.17: Global MASTER-Net observations report
  27. IPN triangulation of GRB 240101C (short)
  28. GRB GRB240101C: Fermi GBM observation
  29. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  30. GRB 240101C: AstroSat CZTI detection
  31. GRB 240101C: GRBAlpha detection
  32. GRB 240101C: Fermi GBM Final Localization
  33. Swift GRB240101.85: Global MASTER-Net observations report
  34. Fermi trigger No 725806648: Global MASTER-Net observations report
  35. Fermi trigger No 725592555: Global MASTER-Net observations report
  36. Fermi trigger No 725143760: Global MASTER-Net observations report
  37. Fermi trigger No 724781422: Global MASTER-Net observations report
  38. GRB 231215A: AMI-LA radio detection
  39. GRB 231214A: Swift-BAT refined analysis
  40. GRB 231216A: BOOTES-2/TELMA optical upper limit
  41. GRB 231205B: VZLUSAT-2 detection
  42. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  43. GRB 231215A: Swift/UVOT Detection
  44. GRB 231210B: MeerLICHT afterglow observations
  45. IceCube Alert 231211.03: Global MASTER-Net observations report
  46. Fermi trigger No 723906955: Global MASTER-Net observations report
  47. IPN triangulation of GRB 231205A
  48. Fermi trigger No 723581802: Global MASTER-Net observations report
  49. GRB 231205B: Nanshan/HMT optical upper limit
  50. GRB 231205A: DDOTI Upper Limits on the Afterglow
  51. Fermi trigger No 723326169: Global MASTER-Net observations report
  52. LIGO/Virgo/KAGRA S231129ac: Upper limits from Swift/BAT-GUANO
  53. Fermi trigger No 723412808: Global MASTER-Net observations report
  54. GRB 231129A: Swift-BAT refined analysis
  55. Fermi trigger No 722653947: Global MASTER-Net observations report
  56. Fermi trigger No 722400249: Global MASTER-Net observations report
  57. GRB 231117A: GTC Near-Infrared Observations
  58. Konus-Wind detection of GRB 231020A
  59. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  60. Fermi trigger No 722039659: Global MASTER-Net observations report
  61. GRB 231115A : OHP/T120 optical upper limit
  62. GRB 231117A : MITSuME Akeno optical upper limits
  63. Fermi GRB 231115A: Global MASTER-Net observations report
  64. GRB 231113A (short): Glowbug gamma-ray detection
  65. Swift GRB231111.60: Global MASTER-Net observations report
  66. Fermi trigger No 721204446: Global MASTER-Net observations report
  67. Fermi GRB 231108A: Global MASTER-Net observations report
  68. Fermi GRB 231106A: Global MASTER-Net observations report
  69. GRB 231104A: NOT upper limit
  70. Fermi GRB 231103A: Global MASTER-Net observations report
  71. Swift GRB231104.07: Global MASTER-Net observations report
  72. GRB 231030B: AstroSat CZTI detection
  73. Fermi GRB 231030B: Global MASTER-Net observations report
  74. Fermi trigger No 720224759: Global MASTER-Net observations report
  75. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  76. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  77. GRB 231020A: AstroSat CZTI detection
  78. Fermi trigger No 719846439: Global MASTER-Net observations report
  79. LIGO/Virgo/KAGRA S231021az: Coverage and upper limits from MAXI/GSC observations
  80. GRB 231018A: Fermi GBM Detection
  81. LIGO/Virgo/KAGRA S230919bj: Identification of a GW compact binary merger candidate
  82. Fermi trigger No 716449174: Global MASTER-Net observations report
  83. GRB 230903A: Enhanced Swift-XRT position
  84. GRB 230903A: Swift-BAT refined analysis
  85. Fermi trigger No 715552087: Global MASTER-Net observations report
  86. GRB 230826A: Swift-BAT refined analysis
  87. AT 2023qxj: ZTF discovery of the likely afterglow of Fermi GRB 230827256
  88. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  89. Swift GRB230821.64: Global MASTER-Net observations report
  90. GRB 230818A: Tautenburg observations
  91. GRB 230818A: Leavitt Observatory upper limit
  92. GRB 230818A: SAO RAS Zeiss-1000 observations
  93. Fermi GRB 230818A: Global MASTER-Net observations report
  94. Fermi trigger No 713974668: Global MASTER-Net observations report
  95. Swift GRB230818.98: Global MASTER-Net observations report
  96. IPN triangulation of GRB 230815B
  97. GRB 230812B: continued SAO RAS optical observation
  98. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  99. Fermi trigger No 713205976: Global MASTER-Net observations report
  100. Fermi GRB 230807A: Global MASTER-Net observations report

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