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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"

28257 results found.

  1. LIGO/Virgo/KAGRA S230602ap: Zwicky Transient Facility observations
  2. GRB 230606A: Swift-XRT refined Analysis
  3. GRB 230604A: GRBAlpha detection
  4. GRB 230606A: Swift/UVOT Upper Limits
  5. GRB 230606A: Enhanced Swift-XRT position
  6. GRB 230606A: Swift detection of a burst
  7. Super-Kamiokande: Neutrino search for SN2023ixf
  8. GRB 230604A: AstroSat CZTI detection of a short GRB
  9. IceCube-230603A - IceCube observation of a high-energy neutrino candidate track-like event
  10. GRB 230603A: Fermi GBM Final Real-time Localization
  11. GRB 230521A: VZLUSAT-2 detection
  12. GRB 230522A: GRBAlpha and VZLUSAT-2 joint detection
  13. GRB 230525A: CALET Gamma-Ray Burst Monitor detection
  14. LIGO/Virgo/KAGRA S230529ay: Zwicky Transient Facility observations
  15. LIGO/Virgo/KAGRA S230528a: Zwicky Transient Facility observations
  16. LIGO/Virgo/KAGRA S230527ch: Zwicky Transient Facility observations
  17. LIGO/Virgo/KAGRA S230529ay: AstroSat CZTI non-detection and upper limits
  18. LIGO/Virgo/KAGRA S230529ay: Upper limits from Fermi-GBM Observations
  19. GRB 230529A: Fermi GBM Final Real-time Localization
  20. GRB 230525A: Fermi GBM Detection
  21. GRB 230525A: Fermi GBM Final Localization
  22. GRB 230523B: GRBAlpha detection
  23. LIGO/Virgo/KAGRA S230524x: Retraction of GW compact binary merger candidate
  24. IceCube-230524A - IceCube observation of a high-energy neutrino candidate track-like event
  25. GRB 230524B: AstroSat CZTI detection
  26. GRB 230524A: AstroSat CZTI detection
  27. GRB 230524A: AGILE detection
  28. GRB 230524A: Fermi GBM Final Real-time Localization
  29. LIGO/Virgo/KAGRA S230521k: MASTER new OT discovery
  30. GRB 230523B: Name correction from GCN Circular 33859
  31. GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
  32. LIGO/Virgo/KAGRA S230521k: Additional candidates from Zwicky Transient Facility
  33. GRB 230523A: Fermi GBM Final Real-time Localization
  34. LIGO/Virgo/KAGRA S230521k: Zwicky Transient Facility observations
  35. GRB 230518B: VZLUSAT-2 detection
  36. IPN triangulation of GRB 230518A (short)
  37. GRB 230520A: CALET Gamma-Ray Burst Monitor detection
  38. GRB 230521A: Fermi GBM Final Real-time Localization
  39. GRB 230520B: Fermi GBM Final Real-time Localization
  40. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  41. GRB 230520A: MAXI/GSC detection
  42. LIGO/Virgo S230518h: AGILE/MCAL observations
  43. GRB 230518A: Swift/BAT-GUANO detection
  44. LIGO/Virgo S230518h: Swift XRT observations, 8 X-ray sources
  45. GRB 230518A: Fermi GBM Final Real-time Localization
  46. LIGO/Virgo/KAGRA S230518h: AstroSat CZTI non-detection and upper limits
  47. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  48. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  49. GRB 230510B: GRBAlpha detection
  50. GRB 230517A: Fermi GBM Final Real-time Localization
  51. GRB 230510B: Fermi GBM detection
  52. GRB 230516A: Fermi GBM Final Real-time Localization
  53. IPN triangulation of GRB 230511D (short)
  54. IPN triangulation of GRB 230512A
  55. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  56. GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate
  57. GRB 230512A: Zwicky Transient Facility non-detection of GRB afterglow candidate
  58. GRB 230512A: Liverpool Telescope observations
  59. GRB 230512A: GIT non detection of afterglow candidate
  60. GRB 230512A: Kitab possible afterglow candidate
  61. GRB 230512A: GRBAlpha detection
  62. GRB 230510A: GRBAlpha detection
  63. GRB 230513A: Fermi GBM Final Real-time Localization
  64. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  65. GRB 230512A: Swift-XRT observations
  66. GRB 230512A: Fermi GBM detection
  67. GRB 230512A: Tiled Swift observations
  68. GRB 230512A: Fermi-LAT detection
  69. GRB 230512A: AstroSat CZTI detection
  70. GRB 230512A: Fermi GBM Final Localization
  71. GRB 230510A: GIT optical upper limits
  72. GRB 230510A: LCOGT Optical Upper Limit
  73. GRB 230511D: Fermi GBM Final Real-time Localization
  74. GRB 230510A: Swift/UVOT Observations
  75. IceCube-230511A: IceCube observation of a high-energy neutrino candidate
  76. GRB 230510B: AstroSat CZTI detection
  77. GRB 230511C: Fermi GBM Final Localization
  78. GRB 230511B: Fermi GBM Final Real-time Localization
  79. GRB 230511A: Fermi GBM Final Real-time Localization
  80. GRB 230510A: Fermi GBM detection
  81. GRB 230510A: Gaoyazi/GOT optical upper limit
  82. GRB 230510B: CALET Gamma-Ray Burst Monitor detection
  83. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  84. GRB 230510A: Nanshan/NEXT optical afterglow detection
  85. GRB 230510B: MAXI/GSC detection
  86. GRB 230510B: Fermi GBM Final Real-time Localization
  87. GRB 230506B: Fermi GBM detection
  88. GRB 230510A: Swift-XRT refined Analysis
  89. GRB 230510A: Enhanced Swift-XRT position
  90. GRB 230506C: Fermi GBM detection
  91. GRB 230510A: Swift detection of a burst
  92. GRB 230510A: Fermi GBM Final Real-time Localization
  93. GRB 230506B: Swift/UVOT further analysis
  94. GRB 230307A: JWST second-epoch observations
  95. GRB 230506C: Swift-XRT refined Analysis
  96. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  97. GRB 230506B: LCOGT Optical Upper Limits
  98. GRB 230506C: Swift/UVOT Upper Limits
  99. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  100. GRB 230506B: Swift-XRT refined Analysis

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