Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

28094 results found.

  1. GRB 240118A: Swift-XRT afterglow detection
  2. GRB 240118C: Fermi GBM Observation
  3. IceCube-240105A: Detection of NIR flare of PKS 0446+11 with WINTER
  4. GRB 240118C: Swift/BAT-GUANO detection of a burst
  5. GRB 240118D: AstroSat CZTI detection
  6. GRB 240118A: AbAO optical upper limit
  7. GRB 240118A: NuSTAR Offline Analysis of the GRB
  8. GRB 240117A: Glowbug gamma-ray detection
  9. GRB 240118A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  10. GRB 240118C: BALROG localization (Fermi Trigger 727291408 / GRB 240118725)
  11. GRB 240118A: Fermi GBM Observation
  12. GRID detection of GRB 231230A
  13. GRB 240115A: Swift/BAT-GUANO detection of a short burst
  14. Swift Triggers 1209369 and 1209370 are not astrophysical events
  15. GRB 240115B: AstroSat CZTI detection
  16. LIGO/Virgo/KAGRA S240109a: Upper limits from Swift/BAT-GUANO
  17. GRB 240115B: Fermi GBM Detection
  18. GRB 240112D: Glowbug gamma-ray detection
  19. GRB 240112C: Glowbug gamma-ray detection
  20. GRB 240112C: VZLUSAT-2 detection
  21. GRB 240114A: MAXI/GSC detection
  22. GRB 240112C: Swift/UVOT Detection
  23. GRB 240112C: Fermi GBM Detection
  24. Fermi trigger No 726773850: Global MASTER-Net observations report
  25. GRB 240112C: Swift-XRT refined Analysis
  26. GRB 240112C: SAO RAS optical observations
  27. GRB 240109A: Swift-BAT refined analysis
  28. GRB 240112C: Swift detection of a burst with an optical counterpart
  29. GRB 240112A: GECAM detection of a burst
  30. GRB 240109A: Fermi GBM Observation
  31. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 0446+11, located inside the IceCube-240105A error region
  32. GRB 240108A: Glowbug gamma-ray detection
  33. GRB 240106B: Glowbug gamma-ray detection
  34. GRB 240106A: Glowbug gamma-ray detection
  35. IceCube-240105A: Upper limits from a search for additional neutrino events in IceCube
  36. LIGO/Virgo/KAGRA S240109a: Updated Sky localization
  37. GRB 231215A: radio detection with the VLA
  38. GRB 230818A: further radio observations with the VLA
  39. GRB 230812B: further radio observations with the VLA
  40. Swift GRB240109.17: Global MASTER-Net observations report
  41. LIGO/Virgo/KAGRA S240109a: Identification of a GW compact binary merger candidate
  42. LIGO/Virgo/KAGRA S240104bl: Upper limits from Swift/BAT-GUANO
  43. LIGO/Virgo/KAGRA S240107b: Updated Sky localization and Source Classification
  44. GRB 240107A: MAXI/GSC detection
  45. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  46. IPN triangulation of GRB 240101C (short)
  47. GRB 240101A: 1.3m DFOT optical observations
  48. GRB 240102A: 1.3m DFOT optical upper limit
  49. GRB 240101B: 1.3m DFOT optical upper limit
  50. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  51. LIGO/Virgo/KAGRA S240104bl: Updated Sky localization
  52. LIGO/Virgo/KAGRA S240104bl: Identification of a GW compact binary merger candidate
  53. GRB 240102A: Swift-BAT refined analysis
  54. GRB 240102A: Swift/UVOT Upper Limits
  55. GRB 231230A: Swift-BAT refined analysis
  56. GRB 240101A: Swift-BAT refined analysis
  57. GRB 240101B: Swift-BAT refined analysis
  58. GRB 240102A: Enhanced Swift-XRT position
  59. GRB 240101B: Swift-XRT refined Analysis
  60. GRB 240102A: Swift-XRT refined Analysis
  61. GRB 240102A: LCOGT Optical Upper Limits
  62. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  63. IceCube-Cascade 231230A: Upper limits from a search for additional neutrino events in IceCube
  64. GRB 240102A: Swift detection of a burst
  65. GRB 240101C: GRBAlpha detection
  66. GRB 240101B: Swift/UVOT Upper Limits
  67. GRB 240101A: Swift/UVOT Upper Limits
  68. GRB 240101A: Swift-XRT refined Analysis
  69. GRB 240101B: Enhanced Swift-XRT position
  70. GRB 240101A: Enhanced Swift-XRT position
  71. GRB 240101B: Swift detection of a burst
  72. LIGO/Virgo/KAGRA S231231ag: Updated Sky localization and Source Classification
  73. LIGO/Virgo/KAGRA S231231ag: Identification of a GW compact binary merger candidate
  74. GRB231230A: Fermi GBM Observation
  75. GRB 231230A: Swift-XRT refined Analysis
  76. GRB 231230A: Enhanced Swift-XRT position
  77. GRB 231230A: Swift/UVOT Upper Limits
  78. GRB 231230A: NOT optical upper limits
  79. GRB 231230A: Swift detection of a burst
  80. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  81. LIGO/Virgo/KAGRA S231226av: Updated Sky localization
  82. LIGO/Virgo/KAGRA S231226av: Identification of a GW compact binary merger candidate
  83. LIGO/Virgo/KAGRA S231224e: Updated Sky localization and Source Classification
  84. LIGO/Virgo/KAGRA S231224e: Identification of a GW compact binary merger candidate
  85. LIGO/Virgo/KAGRA S231223j: Updated Sky localization
  86. GRB 231222B: Swift-XRT afterglow detection
  87. LIGO/Virgo/KAGRA S231223j: Identification of a GW compact binary merger candidate
  88. GRB 231222B: Fermi GBM Detection
  89. IceCube-231211A: GRANDMA observations of PKS2047+098
  90. GRID detection of GRB 231215A
  91. GRB 231220A: Swift-XRT follow-up observations
  92. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  93. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  94. GRB 231214B: Fermi GBM observation
  95. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  96. GRB 231215A: AMI-LA radio detection
  97. GRB 231216A: Nanshan/HMT optical upper limit
  98. GRB 231216A: LCOGT Optical Upper Limits
  99. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  100. GRB 231216A: Swift-XRT refined analysis correction

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov