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"

35958 results found.

  1. Fermi GRB 230723A: Global MASTER-Net observations report
  2. GRB 230723A: Fermi GBM Final Real-time Localization
  3. IPN triangulation of GRB 230715D
  4. Swift Trigger 1180063 is not a GRB
  5. Swift Trigger 1180060 is not a GRB
  6. Swift Trigger 1180055 is not a GRB
  7. GRB 230718A: Final Localization Correction
  8. GRB 230718A: Fermi GBM Final Real-time Localization
  9. Fermi Gamma-ray Burst Monitor trigger 711329677/230717982 is not a GRB
  10. IPN triangulation of GRB 230712C (short)
  11. IPN triangulation of GRB 230712A (short)
  12. GRB 230717A: Fermi GBM Final Real-time Localization
  13. GRB 230715A: Fermi GBM Final Real-time Localization
  14. Fermi GRB 230713A: Global MASTER-Net observations report
  15. GRB 230713A: Fermi GBM Final Real-time Localization
  16. GRB 230709B: CALET Gamma-Ray Burst Monitor detection
  17. GRB 230703A: CALET Gamma-Ray Burst Monitor detection
  18. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  19. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  20. GRB 230712B: Fermi GBM Final Localization
  21. GRB 230707A: Swift/BAT-GUANO position correction
  22. GRB 230712A: Fermi GBM Final Real-time Localization
  23. GRB 230709C: GRBAlpha detection
  24. GRB 230709B: GRBAlpha detection
  25. GRB 230709C: Fermi GBM Detection
  26. GRB 230709C: Fermi GBM Final Localization
  27. GRB 230707B: Fermi GBM Observation
  28. GRB 230710A: Fermi GBM Final Real-time Localization
  29. GRB 230709C: AstroSat CZTI detection
  30. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  31. GRB 230703A detected with multiple GRID detectors
  32. GRB 230709C: BALROG localization (Fermi Trigger 710617111 / GRB 230709735)
  33. GRB 230709B: BALROG localization (Fermi Trigger 710614579 / GRB 230709706)
  34. Swift Trigger 1178410: possible GRB 230709A
  35. GRB 230628C: GRID Detection
  36. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  37. GRB 230707A: Swift-XRT observations
  38. GRB 230707B: Fermi GBM Final Real-time Localization
  39. GRB 230707A: Fermi GBM Detection
  40. GRB 230707A: Swift ToO observations
  41. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  42. Fermi GRB 230707A: Global MASTER-Net observations report
  43. GRB 230707A: Fermi GBM Final Real-time Localization
  44. IBAS trigger number 10311: not a real GRB
  45. GRB 230625A: Detection by GRID
  46. GRB 230626A: VZLUSAT-2 detection
  47. GRB 230328B: LBT detection of the likely host galaxy
  48. Konus-Wind detection of GRB 220623A
  49. GRB 230701B: AstroSat CZTI detection
  50. GRB 230628E: Swift/UVOT Detection
  51. GRB 230628E: Swift-BAT refined analysis
  52. GRB 230702A: Fermi GBM Final Real-time Localization
  53. GRB 230628E: ATCA rapid radio follow-up
  54. GRB 230701A: Fermi GBM Final Real-time Localization
  55. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  56. IPN triangulation of GRB 230625B (ultra-long)
  57. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  58. GRB 230628E - VLT spectroscopic observations
  59. Fermi GRB 230628C: Global MASTER-Net observations report
  60. GRB 230625B: AstroSat CZTI detection
  61. GRB230628E: VLT optical identification of afterglow candidate
  62. GRB 230628E: Swift-XRT refined Analysis
  63. GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
  64. GRB 230628A: Enhanced Swift-XRT position
  65. Fermi GRB 230628D: Global MASTER-Net observations report
  66. GRB 230628E: LCOGT Optical Upper Limit
  67. GRB 230628E: Swift detection of a burst
  68. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  69. GRB 230628D: Fermi GBM Final Real-time Localization
  70. GRB 230628C: Fermi GBM Final Real-time Localization
  71. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  72. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  73. GRB 230628A: Fermi GBM Final Localization
  74. GRB 230626A: GRBAlpha detection
  75. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  76. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  77. GRB230626A: Fermi GBM Detection
  78. Konus-Wind detection of GRB 230616A
  79. GRB 230618A: Swift-BAT refined analysis
  80. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  81. GRB 230622A: Swift-BAT refined analysis
  82. GRB 230623A: Swift-XRT observations
  83. GRB 230625A: Fermi GBM Final Real-time Localization
  84. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  85. ATLAS23msn/ZTF23aaoohpy/AT2023lcr: Zeiss-1000 of Koshka observatory optical observations
  86. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  87. GRB 230623A: Tiled Swift observations
  88. MAXI GRB 230623A: MASTER optical observations
  89. GRB 230623A: Tiled Swift observations
  90. GRB 230622A: ATCA rapid radio follow-up
  91. GRB 230622A: Swift-XRT refined Analysis
  92. GRB 230623A: MAXI/GSC detection
  93. Swift GRB 230622A: Global MASTER-Net observations report
  94. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  95. GRB 230622A: Swift detection of a burst
  96. GRB 230621A: Fermi GBM Final Localization Correction
  97. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  98. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  99. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  100. ZTF23aaoohpy/AT2023lc: Mondy optical observations

Advanced

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