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"

12091 results found.

  1. GRB 230712B: Fermi GBM Final Localization
  2. GRB 230709C: AstroSat CZTI detection
  3. Fermi-LAT gamma-ray observations of IceCube-230708A
  4. Fermi-LAT gamma-ray observations of IceCube-230707B
  5. Fermi-LAT gamma-ray observations of IceCube-230707A
  6. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  7. IceCube Alert 230708.35: Global MASTER-Net observations report
  8. GRB 230707B: Fermi GBM Final Real-time Localization
  9. Integral GRB230706.70: Global MASTER-Net observations report
  10. Fermi trigger No 710117592: Global MASTER-Net observations report
  11. GRB 230328B: LBT detection of the likely host galaxy
  12. Konus-Wind detection of GRB 220623A
  13. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  14. GRB 230625B: AstroSat CZTI detection
  15. GRB 230628E: Swift-XRT refined Analysis
  16. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  17. GRB 230628D: Fermi GBM Final Real-time Localization
  18. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  19. LIGO/Virgo/KAGRA S230627c: Global MASTER-Net observations report
  20. LIGO/Virgo/Kagra S230627c: NED Galaxies in the Localization Volume
  21. Konus-Wind detection of GRB 230616A
  22. LIGO/Virgo/KAGRA S230627c: Coverage and upper limits from MAXI/GSC observations
  23. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  24. GRB 230622A: Swift-BAT refined analysis
  25. ATLAS23msn/ZTF23aaoohpy/AT2023lcr: Zeiss-1000 of Koshka observatory optical observations
  26. MAXI GRB 230623A: MASTER optical observations
  27. GRB 230623A: MAXI/GSC detection
  28. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  29. IceCube-Cascade 230621A: Upper limits from a search for additional neutrino events in IceCube
  30. Fermi trigger No 709083929: Global MASTER-Net observations report
  31. AT2023lcr: VLA radio detection
  32. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  33. LIGO/Virgo S230620ad: Global MASTER-Net observations report
  34. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Swift/UVOT detection
  35. LIGO/Virgo S230620au: Global MASTER-Net observations report
  36. ZTF23aaoohpy/AT2023lc: Mondy optical observations
  37. IPN triangulation of GRB 230616A (short)
  38. AT2023lcr: Neil Gehrels Swift Observatory X-ray detection
  39. AT2023lcr: Pan-STARRS & ATLAS Observations
  40. ZTF23aaoohpy/AT2023lcr: Keck/LRIS spectroscopy and redshift
  41. ZTF23aaoohpy/AT2023lcr: Xinglong-2.16m optical observations
  42. LIGO/Virgo S230620al: Global MASTER-Net observations report
  43. LIGO/Virgo S230620af: Global MASTER-Net observations report
  44. LIGO/Virgo S230620z: Global MASTER-Net observations report
  45. LIGO/Virgo S230620w: Global MASTER-Net observations report
  46. LIGO/Virgo S230619bg: Global MASTER-Net observations report
  47. LIGO/Virgo S230620g: Global MASTER-Net observations report
  48. LIGO/Virgo S230619ay: Global MASTER-Net observations report
  49. LIGO/Virgo/KAGRA S230615az: GRANDMA observations of GOTO and GIT candidates
  50. LIGO/Virgo S230619e: Global MASTER-Net observations report
  51. LIGO/Virgo S230618at: Global MASTER-Net observations report
  52. GRB 230618A: Swift-XRT refined Analysis
  53. LIGO/Virgo S230618r: Global MASTER-Net observations report
  54. LIGO/Virgo S230616aa: Global MASTER-Net observations report
  55. LIGO/Virgo S230615ak: Global MASTER-Net observations report
  56. LIGO/Virgo S230618k: Global MASTER-Net observations report
  57. LIGO/Virgo S230617bc: Global MASTER-Net observations report
  58. LIGO/Virgo S230617aq: Global MASTER-Net observations report
  59. LIGO/Virgo S230617ab: Global MASTER-Net observations report
  60. Swift GRB 230618A: Global MASTER-Net observations report
  61. LIGO/Virgo S230617aj: Global MASTER-Net observations report
  62. GRB 230618A: Swift detection of a burst
  63. LIGO/Virgo/KAGRA S230615az: Non-Detections of GROWTH-India Candidates from GECKO Optical Observations
  64. GRB 230616A: AstroSat CZTI detection
  65. LIGO/Virgo S230616s: Global MASTER-Net observations report
  66. LIGO/Virgo/KAGRA S230615az: GROWTH-India candidates
  67. GRB 230614C: AstroSat CZTI detection
  68. LIGO/Virgo S230614ac: Global MASTER-Net observations report
  69. Fermi trigger No 708426906: Global MASTER-Net observations report
  70. LIGO/Virgo S230609u: Global MASTER-Net observations report
  71. GRB 230608A: AstroSat CZTI detection
  72. LIGO/Virgo S230608as: Global MASTER-Net observations report
  73. LIGO/Virgo S230609a: Global MASTER-Net observations report
  74. LIGO/Virgo S230608ah: Global MASTER-Net observations report
  75. LIGO/Virgo/KAGRA S230608as: Identification of a GW compact binary merger candidate
  76. Fermi trigger No 707039690: Global MASTER-Net observations report
  77. GRB 230606A: Swift-XRT refined Analysis
  78. GRB 230606A: Swift detection of a burst
  79. Fermi-LAT gamma-ray observations of IceCube-230603A
  80. GRB 230604A: AstroSat CZTI detection of a short GRB
  81. LIGO/Virgo S230603aa: Global MASTER-Net observations report
  82. LIGO/Virgo S230602ap: Global MASTER-Net observations report
  83. LIGO/Virgo S230601bf: Global MASTER-Net observations report
  84. LIGO/Virgo/KAGRA S230527ch: Zwicky Transient Facility observations
  85. LIGO/Virgo/KAGRA S230529ay: Upper limits from CALET observations.
  86. LIGO/Virgo/KAGRA S230529ay: AstroSat CZTI non-detection and upper limits
  87. LIGO/Virgo S230529ay: Global MASTER-Net observations report
  88. LIGO/Virgo/KAGRA S230529ay: Coverage and upper limits from MAXI/GSC observations
  89. LIGO/Virgo S230525a: Global MASTER-Net observations report
  90. Fermi-LAT gamma-ray observations of IceCube-230524A
  91. GRB 230510A: Swift-BAT refined analysis
  92. GRB 230525A: Fermi GBM Final Localization
  93. IceCube Alert 230524.47: Global MASTER-Net observations report
  94. GRB 230524B: AstroSat CZTI detection
  95. GRB 230524A: AstroSat CZTI detection
  96. LIGO/Virgo S230524b: Global MASTER-Net observations report
  97. Fermi trigger No 706536788: Global MASTER-Net observations report
  98. LIGO/Virgo S230522a: Global MASTER-Net observations report
  99. LIGO/Virgo S230521k: Global MASTER-Net observations report
  100. LIGO/Virgo S230520ae: Global MASTER-Net observations report

Advanced

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