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"

5821 results found.

  1. GRB 190109B: Swift detection of a burst
  2. GRB 190109A: Swift detection of a burst
  3. GRB 190103B: Swift detection of a burst
  4. GRB 181228A: MITSuME Akeno optical upper limits
  5. GRB 181228A: Global MASTER Net OT detection
  6. GRB 181222B: Global MASTER Net observations of short bright Fermi GRB
  7. GRB 181222B: Global MASTER Net observations of the short bright Fermi GRB error box.
  8. Swift Trigger 878504 is not astrophysical
  9. GRB 181222A: MAXI/GSC detection
  10. GRB 181126B: KAIT Follow-Up Observations of a Fermi Short GRB (Trigger 564897175)
  11. MASTER: OTs detection during Fermi alert trigger 565936249 early observations
  12. GRB 181126B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 564897175)
  13. GRB 181201A: continued optical observations in SAAO and Chilesope
  14. GRB 181202A: Global MASTER-Net optical observations
  15. GRB 181201A: NOT optical observations
  16. Short-duration GRB 181121.4: MASTER-Tavrida possible OT detection near the PGC galaxy during large Fermi error box inspection
  17. GRB 181126A: Fermi GBM observation
  18. GRB 181126A: Prompt enhanced Swift-XRT position
  19. GRB 181126A: Swift detection of a burst
  20. GRB 181123B: Global MASTER Net optical inspection
  21. GRB 181110A: Swift/UVOT Detection
  22. GRB 181110A: optical observations from iTelescope SSO
  23. GRB 181110A: MITSuME Akeno optical observation
  24. GRB 181110A: Swift detection of a burst with an optical counterpart
  25. GRB 181028A: Insight-HXMT/HE detection
  26. GRB 181028A: CALET Gamma-Ray Burst Monitor detection
  27. Konus-Wind observation of GRB 181028A
  28. GRB 181030A: SAO RAS optical observations
  29. GRB 181030A: Swift detection of a burst with a possible optical counterpart
  30. IPN Triangulation of GRB 181028A (long)
  31. GRB 181028A: Fermi GBM observation
  32. GRB 181028A: Fermi-LAT detection
  33. IceCube-181023A: HAWC follow-up
  34. Search for counterparts to IceCube-181023A with IceCube
  35. GRB 181022A: MITSuME Akeno optical upper limits
  36. Baksan Neutrino BNO 181021: Global MASTER-net Optical Follow-up Observations
  37. GRB 181020A: Swift detection of a burst with an optical counterpart
  38. GRB 181016A: Swift detection of a burst
  39. Search for counterparts to IceCube-181014A with IceCube
  40. GRB 181011A: MAXI/GSC detection
  41. GRB180913A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 558557292)
  42. GRB 181008B: Global MASTER Net optical inspection
  43. GRB 180930A: TSHAO optical upper limit
  44. INTEGRAL detections of the prompt gamma-ray emission of GRB 180914B
  45. GRB 180925A: Insight-HXMT/HE detection
  46. GRB 180925A: Swift detection of a burst
  47. GRB 180924A: MASTER inspection
  48. GRB 180924A: Swift detection of a burst
  49. GRB 180923A: MASTER inspection MAXI/GSC error box
  50. GRB 180923A: MAXI/GSC detection
  51. GRB 180914B: DDOTI/OAN Detection and Confirmation of Fading
  52. GRB 180914B: GOTO optical detection
  53. GRB 180914B : continued TSHAO optical observations
  54. GRB 180914B: MASTER OT automatic dtection
  55. GRB 180914B : TSHAO optical observations
  56. GRB 180914B: Continued RATIR Optical and NIR Observations
  57. GRB 180914B: AGILE/MCAL refined analysis
  58. GRB180914B: Swift UVOT detection of an optical afterglow
  59. GRB 180914B: RATIR Optical and NIR Observations
  60. GRB 180914B: KAIT Optical Afterglow Candidate
  61. GRB 180914A: RATIR Optical and NIR Observations
  62. GRB 180914A: MASTER automatic inspection
  63. GRB 180914B: AGILE/MCAL detection of a burst
  64. Fermi-LAT Gamma-ray Observations of IceCube-180908A
  65. INTEGRAL observation of IceCube-180908A
  66. Search for counterparts to IceCube-180908A with IceCube
  67. IceCube-180908A: HAWC follow-up
  68. IceCube-180908A - IceCube observation of a high-energy neutrino candidate event
  69. GRB 180905A: RATIR Optical and NIR Observations
  70. GRB 180905A: MITSuME Akeno optical upper limits
  71. GRB 180904A: AbAO optical upper limit
  72. GRB 180904A: RATIR Optical and NIR Observations
  73. GRB 180905A: Swift detection of a burst
  74. IPN Triangulation of GRB 180824A (short)
  75. GRB 180823A: Swift detection of a burst
  76. GRB 180818B: Swift detection of a burst
  77. GRB 180818A: Swift detection of a burst
  78. GRB 180728A: MASTER early polarization and 19 days monitoring
  79. GRB180809B TUG T60 observations
  80. GRB180809B: MASTER Triple Independent Automatic OT Detection
  81. GRB 180809B: LCO Sutherland observations
  82. GRB 180809B: GROND Detection of the NIR Afterglow
  83. GRB180809B: MASTER OT observation
  84. GRB 180809A: iTelescope optical limit
  85. GRB 180723A: AstroSat CZTI detection
  86. GRB 180805B: Swift detection of a burst
  87. GRB 180805A: Swift detection of a burst
  88. GRB 180728B: MASTER optical observations short GRB IPN error box
  89. Konus-Wind observation of GRB 180728B
  90. GRB 180728B: Fermi GBM detection
  91. IPN Triangulation of GRB 180728B (short)
  92. GRB 180728A: MASTER OT (= new object) detection
  93. GRB 180723A: Fermi GBM detection
  94. GRB 180723A: CALET Gamma-Ray Burst Monitor detection
  95. GRB 180720B: MASTER Global Net OT observations
  96. GRB 180720C: BOOTES-2/TELMA optical observations
  97. GRB 180722A: MASTER optical observation
  98. GRB 180722A: MAXI/GSC detection
  99. IceCube-171106A: MASTER optical observation
  100. IceCube-170922A: First Optical observations of the Neutrino Trigger by MASTER Global Net and 25 IceCube alerts inspection.

Advanced

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