Skip to main content
End of Swift Science Operations, CHIME Notices Unavailable During Upgrade. 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"

23734 results found.

  1. GRB 240108A: Glowbug gamma-ray detection
  2. GRB 240106B: Glowbug gamma-ray detection
  3. GRB 240106A: Glowbug gamma-ray detection
  4. Konus-Wind detection of GRB 240101C
  5. GRB 231215A: radio detection with the VLA
  6. GRB 230818A: further radio observations with the VLA
  7. GRB 230812B: further radio observations with the VLA
  8. Swift GRB240109.17: Global MASTER-Net observations report
  9. GRB 240109A: Swift detection of a short burst
  10. IceCube-240105A: JCMT SCUBA2 Detection of Two Bright Submillimeter Sources
  11. GRB 240106A: GRBAlpha detection
  12. GRB 240107A: MAXI/GSC detection
  13. Fermi trigger No 726347794: Global MASTER-Net observations report
  14. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  15. GRB 240106B: Fermi GBM Final Real-time Localization
  16. Fermi trigger No 726194053: Global MASTER-Net observations report
  17. GRB 240106A: Fermi GBM Final Real-time Localization
  18. IPN triangulation of GRB 240101C (short)
  19. GRB GRB240101C: Fermi GBM observation
  20. IceCube Alert 240105.52: Global MASTER-Net observations report
  21. GRB 240102A: Swift-BAT refined analysis
  22. GRB 231230A: Swift-BAT refined analysis
  23. GRB 240101A: Swift-BAT refined analysis
  24. GRB 240101B: Swift-BAT refined analysis
  25. Fermi trigger No 725857207: Global MASTER-Net observations report
  26. GRB240102A: BOOTES-6/DPRT optical upper limit
  27. GRB 240102A: Swift detection of a burst
  28. GRB 240101C: GRBAlpha detection
  29. GRB 240101B: Swift/UVOT Upper Limits
  30. GRB 240101A: Swift/UVOT Upper Limits
  31. GRB 240101B: KAIT Optical Upper Limit
  32. GRB 240101A: KAIT Optical Upper Limit
  33. Swift GRB240101.85: Global MASTER-Net observations report
  34. Fermi trigger No 725806648: Global MASTER-Net observations report
  35. GRB 231230A: GOTO optical upper limits
  36. GRB 231230A: Swift/UVOT Upper Limits
  37. Fermi trigger No 725592555: Global MASTER-Net observations report
  38. GRB 231230A: Swift detection of a burst
  39. Swift GRB231230.06: Global MASTER-Net observations report
  40. IPN triangulation of GRB 231224A (short)
  41. LIGO/Virgo/KAGRA S231226av: Identification of a GW compact binary merger candidate
  42. Fermi trigger No 725143760: Global MASTER-Net observations report
  43. GRB 231222B: GRBAlpha detection
  44. GRB 231222B: Swift-XRT afterglow detection
  45. LIGO/Virgo/KAGRA S231223j: Identification of a GW compact binary merger candidate
  46. Fermi trigger No 724921799: Global MASTER-Net observations report
  47. LAT GRB231222.31: Global MASTER-Net observations report
  48. GRB 231222B: Fermi-LAT detection
  49. IceCube-231211A: GRANDMA observations of PKS2047+098
  50. GRB 231220A: Swift-XRT follow-up observations
  51. Fermi trigger No 724781422: Global MASTER-Net observations report
  52. Fermi trigger No 724698747: Global MASTER-Net observations report
  53. GRB 231216A: 10.4 m GTC optical upper limit
  54. GRB 231216A: Nanshan/HMT optical upper limit
  55. GRB 231216A: Swift-XRT refined Analysis
  56. GRB 231216A: REM NIR upper limits
  57. GRB 231216A: Swift/UVOT Upper Limits
  58. GRB 231216A: Swift-BAT refined analysis
  59. GRB 231215A: Swift-BAT refined analysis
  60. GRB 231214A: Swift-BAT refined analysis
  61. GRB 231216A: BOOTES-2/TELMA optical upper limit
  62. GRB 231215A: GRBAlpha detection
  63. Swift GRB231216.77: Global MASTER-Net observations report
  64. GRB 231216A: Swift detection of a burst
  65. Konus-Wind detection of GRB 231215A
  66. GRB 231215A: NOT optical observations
  67. GRB 231215A: Redshift from OSIRIS+ / GTC
  68. GRB 231205B: VZLUSAT-2 detection
  69. GRB 231204A: VZLUSAT-2 detection
  70. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  71. GRB 231215A: Swift/UVOT Detection
  72. LIGO/Virgo/KAGRA S231215i: 3 counterpart neutrino candidate events from an IceCube neutrino search
  73. GRB 231215A: BOOTES-4/MET optical detection
  74. GRB 231215A: AGILE detection
  75. Konus-Wind detection of GRB 231210B
  76. Fermi trigger No 724326442: Global MASTER-Net observations report
  77. GRB 231214A: REM optical/NIR upper limits
  78. GRB 231215A: GROWTH-India optical follow-up
  79. GRB 231215A : Nanshan/HMT optical observations
  80. GRB 231215A: AstroSat CZTI detection
  81. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  82. GRB 231214A: Swift-XRT refined Analysis
  83. GRB 231215C: MASTER OT detection
  84. Swift GRB231215.41: Global MASTER-Net observations report
  85. GRB 231215A: Swift detection of a burst
  86. GRB 231214A: Fermi-LAT detection
  87. GRB231214A: BOOTES-6/DPRT optical upper limit
  88. Fermi trigger No 724278269: Global MASTER-Net observations report
  89. Fermi trigger No 724233240: Global MASTER-Net observations report
  90. Swift GRB231214.85: Global MASTER-Net observations report
  91. GRB 231214A: Swift detection of a burst
  92. GRB 231210B: REM optical/NIR upper limits
  93. LIGO/Virgo/KAGRA S231213ap: Identification of a GW compact binary merger candidate
  94. Fermi trigger No 724035412: Global MASTER-Net observations report
  95. GRB 231210B: MeerLICHT afterglow observations
  96. GRB 231210B: Swift-BAT refined analysis
  97. IceCube Alert 231211.03: Global MASTER-Net observations report
  98. GRB 231210B: Swift-XRT refined Analysis
  99. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  100. Fermi trigger No 723906955: 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