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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').

9654 results found.

  1. LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
  2. LIGO/Virgo/KAGRA S231020ba: Identification of a GW compact binary merger candidate
  3. Konus-Wind detection of GRB 231018A
  4. GRB 231017A: GOTO optical upper limits
  5. GRB 231015A: AstroSat CZTI detection
  6. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  7. Fermi-LAT gamma-ray observations of IceCube-231014A
  8. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  9. GRB 231012A: Fermi GBM Final Real-time Localization
  10. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  11. LIGO/Virgo/KAGRA S231008ap: Identification of a GW compact binary merger candidate
  12. Fermi-LAT gamma-ray observations of IceCube-231004A
  13. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  14. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  15. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  16. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A
  17. Konus-Wind detection of GRB 230919A
  18. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  19. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  20. Title: LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  21. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  22. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  23. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  24. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  25. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  26. GRB 230919A: AstroSat CZTI detection
  27. LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate
  28. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  29. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  30. GRB 230917A: AstroSat CZTI detection
  31. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  32. Fermi trigger No 716572242: Global MASTER-Net observations report
  33. Fermi-LAT gamma-ray observations of IceCube-230914A
  34. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  35. Swift GRB230916.11: Global MASTER-Net observations report
  36. Fermi trigger No 716449174: Global MASTER-Net observations report
  37. Fermi trigger No 716419312: Global MASTER-Net observations report
  38. GRB 230913A: Fermi GBM Observation
  39. Swift GRB230913.70: Global MASTER-Net observations report
  40. GRB 230911B: AstroSat CZTI detection
  41. GRB 230911C: Swift-XRT refined Analysis
  42. GRB 230911D: Fermi-LAT detection
  43. GRB230911C: LCOGT Optical Upper Limits
  44. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  45. Konus-Wind detection of GRB 230811D
  46. GRB 230911C: Swift detection of a burst
  47. GRB 230906A: AstroSat CZTI detection
  48. GRB 230908A: GRBAlpha detection
  49. GRB 230908A: AstroSat CZTI detection
  50. Konus-Wind detection of GRB 230906A (short)
  51. IPN triangulation of GRB 230906A (short)
  52. GRB 230905B: AstroSat CZTI detection
  53. Fermi GRB 230906A: Global MASTER-Net observations report
  54. GRB 230905B: GECAM-C detection of a long burst
  55. GRB 230903A: Swift-XRT refined Analysis
  56. GRB 230904C: Fermi GBM Final Localization
  57. Fermi trigger No 715552087: Global MASTER-Net observations report
  58. Fermi trigger No 715429986: Global MASTER-Net observations report
  59. GRB 230903A: LCOGT Optical Upper Limits
  60. GRB 230903A: Swift detection of a burst
  61. Swift GRB230903.72: Global MASTER-Net observations report
  62. GRB 230828A: AstroSat CZTI detection
  63. GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  64. Fermi trigger No 714809315: Global MASTER-Net observations report
  65. Fermi GRB 230827A: Global MASTER-Net observations report
  66. Swift J1727.8-1613 (GRB 230824A): Leavitt Observatory optical observations
  67. GRB 230826A: Mondy optical observations
  68. Swift GRB230826.81: Global MASTER-Net observations report
  69. LIGO/Virgo/KAGRA S230825k: Upper limits from Swift/BAT-GUANO
  70. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  71. Trigger 1187207: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  72. Trigger 1187203: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  73. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  74. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  75. IBAS trigger 10375 is not a GRB
  76. Integral GRB230824.72: Global MASTER-Net observations report
  77. GRB 230824B: AstroSat CZTI detection
  78. GRB 230824A: Swift detection of a burst
  79. LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO
  80. GRB 230818B: AstroSat CZTI detection
  81. GRB 230812B: Assy optical observations, possible SN rise
  82. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  83. Konus-Wind detection of GRB 230818A
  84. GRB 230820A: AstroSat CZTI detection
  85. LIGO/Virgo/KAGRA S230820bq: Identification of a GW compact binary merger candidate
  86. Swift GRB230820.82: Global MASTER-Net observations report
  87. Swift Triggers 1186280 and 1186291 are not GRBs
  88. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  89. GRB 230818A: AstroSat CZTI detection
  90. Fermi GRB 230818A: Global MASTER-Net observations report
  91. Fermi trigger No 713974668: Global MASTER-Net observations report
  92. Swift GRB230818.98: Global MASTER-Net observations report
  93. GRB 230812B: SAO RAS observations, possible re-brightening
  94. GRB 230817A: AstroSat CZTI detection
  95. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  96. GRB 230812B: SAO RAS optical observations
  97. GRB 230816A: Tautenburg observations
  98. GRB 230816A: AKO Optical Observations
  99. GRB 230816A: TShAO and Assy optical observations
  100. Swift GRB230816.80: Global MASTER-Net observations report

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