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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').

9625 results found.

  1. GRB 231117A: AGILE detection of a bright short burst
  2. GRB 231117A: AstroSat CZTI detection of a bright short burst
  3. GRB 231115A: Non-detection of radio emission with CHIME/FRB
  4. GRB 231111A: Swift/UVOT Detection
  5. GRB 231115A: Swift/BAT-GUANO detection of a short burst
  6. Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
  7. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  8. GRB 231115A: Kinder observations with Lulin observatory
  9. GRB231115A: GRANDMA Observations
  10. GECAM-B observation of a short burst from SGR J1555-5402
  11. LIGO/Virgo S231113bw: upper limits from AGILE/MCAL
  12. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  13. LIGO/Virgo/KAGRA S231113cd: Coverage and upper limits from MAXI/GSC observations
  14. LIGO/Virgo/KAGRA S231113bw: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo/KAGRA S231113bw: Identification of a GW compact binary merger candidate
  16. GRB 231111A: Afterglow redshift from OSIRIS+/GTC
  17. GRB 231110A: AstroSat CZTI detection
  18. GRB 231111A: Leavitt Observatory optical observations
  19. GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
  20. GRB 231111A: GECAM-C detection of a long burst (correction)
  21. GRB 231110A: GECAM-B detection (correction)
  22. GRB 231111A: GECAM-C detection of a long burst
  23. GRB 231110A: GECAM detection
  24. GRB 231111A: Swift detection of a burst with an optical counterpart
  25. Swift GRB231111.60: Global MASTER-Net observations report
  26. Swift GRB231110.89: Global MASTER-Net observations report
  27. GRB 231110A: Swift detection of a burst
  28. Fermi GRB 231108A: Global MASTER-Net observations report
  29. Fermi trigger No 721006392: Global MASTER-Net observations report
  30. LIGO/Virgo/KAGRA S231102w: Upper limits from Swift/BAT-GUANO
  31. Fermi GRB 231106A: Global MASTER-Net observations report
  32. Fermi-LAT gamma-ray observations of IceCube-231103A
  33. GRB 231104A: Fermi GBM Observation
  34. Fermi GRB 231103A: Global MASTER-Net observations report
  35. GRB 231104A: AstroSat CZTI detection
  36. GRB 231104A: Fermi-LAT detection
  37. GRB 231104A: Swift/UVOT Upper Limits
  38. Swift GRB231104.07: Global MASTER-Net observations report
  39. Fermi-LAT gamma-ray observations of IceCube-231027A
  40. Fermi trigger No 720498201: Global MASTER-Net observations report
  41. GRB 231030B: GRBAlpha detection
  42. GRB 231030B: Fermi GBM Detection
  43. GRB 231030B: AstroSat CZTI detection
  44. Fermi GRB 231030B: Global MASTER-Net observations report
  45. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  46. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  47. GRID detection of GRB 231020A
  48. GRB 231028A: AstroSat CZTI detection
  49. Fermi trigger No 720224759: Global MASTER-Net observations report
  50. Swift GRB 231028A: Global MASTER-Net observations report
  51. IceCube Alert 231027.18: Global MASTER-Net observations report
  52. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  53. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  54. IC231004A: GRANDMA observations of AT2023uqf/ZTF23abidzvf candidate
  55. GRB 231024A: Fermi GBM Observation
  56. GRB 231020A: AstroSat CZTI detection
  57. GRB 231020B: AstroSat CZTI detection
  58. GRB 231024A: Fermi GBM Final Localization
  59. Fermi trigger No 719846439: Global MASTER-Net observations report
  60. The photometry of the transient in Messier 31 field: GMG observation
  61. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  62. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  63. LIGO/Virgo/KAGRA S231021az: Coverage and upper limits from MAXI/GSC observations
  64. GRB 231020A: Fermi GBM Detection
  65. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  66. GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
  67. GRB 231020B: Fermi GBM Final Real-time Localization
  68. GRB 231020A: BALROG localization (Fermi Trigger / GRB 231020790)
  69. Fermi GRB 231020A: Global MASTER-Net observations report
  70. LIGO/Virgo/KAGRA S231020bw: Identification of a GW compact binary merger candidate
  71. GRB 231020A: Fermi GBM Final Real-time Localization
  72. LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
  73. LIGO/Virgo/KAGRA S231020ba: Identification of a GW compact binary merger candidate
  74. Konus-Wind detection of GRB 231018A
  75. GRB 231017A: GOTO optical upper limits
  76. GRB 231015A: AstroSat CZTI detection
  77. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  78. Fermi-LAT gamma-ray observations of IceCube-231014A
  79. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  80. GRB 231012A: Fermi GBM Final Real-time Localization
  81. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  82. LIGO/Virgo/KAGRA S231008ap: Identification of a GW compact binary merger candidate
  83. Fermi-LAT gamma-ray observations of IceCube-231004A
  84. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  85. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  86. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  87. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A
  88. Konus-Wind detection of GRB 230919A
  89. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  90. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  91. Title: LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  92. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  93. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  94. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  95. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  96. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  97. GRB 230919A: AstroSat CZTI detection
  98. LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate
  99. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  100. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources

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