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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').

3410 results found.

  1. GRB 240204A: Mondy optical afterglow observations
  2. Fermi trigger No 728749569: Global MASTER-Net observations report
  3. GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
  4. Fermi GRB 240204A: Global MASTER-Net observations report
  5. Fermi trigger No 728706420: Global MASTER-Net observations report
  6. IceCube Alert 240204.38: Global MASTER-Net observations report
  7. GRB 240129A: Fermi GBM Observation
  8. Fermi GRB 240127A: Global MASTER-Net observations report
  9. Konus-Wind detection of GRB 240119A (short/hard)
  10. IPN triangulation of GRB 240119A (short)
  11. GRB 240119A: GECAM detection of a short burst
  12. GRB 240119A: AstroSat CZTI detection of a short burst
  13. GRB 240118A: Mondy optical observations
  14. GRB 240119A: Fermi GBM Final Localization
  15. GRID detection of GRB 231230A
  16. IPN triangulation of GRB 240112A (long)
  17. GRB 240112C: Swift/UVOT Detection
  18. Fermi trigger No 726773850: Global MASTER-Net observations report
  19. GRB 240112C: Swift-XRT refined Analysis
  20. Fermi trigger No 726774492: Global MASTER-Net observations report
  21. GRB 240112C: Swift detection of a burst with an optical counterpart
  22. GRB 240112A: GECAM detection of a burst
  23. GRB 230812B: further radio observations with the VLA
  24. GRB 240107A: MAXI/GSC detection
  25. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  26. IceCube-Cascade 231230A: Upper limits from a search for additional neutrino events in IceCube
  27. Fermi trigger No 725806648: Global MASTER-Net observations report
  28. GRB231230A: Fermi GBM Observation
  29. Fermi trigger No 725592555: Global MASTER-Net observations report
  30. GRB 231230A: Swift detection of a burst
  31. GRB 231230A: Fermi GBM Final Real-time Localization
  32. Fermi trigger No 724781422: Global MASTER-Net observations report
  33. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  34. GRB 231205B: VZLUSAT-2 detection
  35. Konus-Wind detection of GRB 231210B
  36. Swift GRB231215.41: Global MASTER-Net observations report
  37. Fermi trigger No 724278269: Global MASTER-Net observations report
  38. GRB 231210B: Swift detection of a burst with optical counterpart
  39. IPN triangulation of GRB 231129C
  40. GRB 231208A: GRBAlpha detection
  41. GRB 231208A: Glowbug gamma-ray detection
  42. GRB 231208A: AstroSat CZTI detection of a faint burst
  43. GRB 231205B: REM optical/NIR upper limits
  44. GRB 231129C: ASIM MXGS observation and localization
  45. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  46. GRB 231205B : MITSuME Akeno optical upper limits
  47. Fermi trigger No 723435916: Global MASTER-Net observations report
  48. Fermi trigger No 723326169: Global MASTER-Net observations report
  49. Fermi trigger No 723149952: Global MASTER-Net observations report
  50. GRB 231129A: VZLUSAT-2 detection
  51. GRB 231129C: AGILE detection
  52. GRB 231129A : MITSuME Akeno optical upper limits
  53. GRB 231129C: MASTER OT detection
  54. GRB 231129A: BOOTES-5/JGT optical upper limit
  55. GRB 231129C: Fermi-LAT detection
  56. GRB 231129A: JinShan optical upper limit
  57. GRB 231129C: GRBAlpha detection
  58. GRB 231129C: Glowbug gamma-ray detection
  59. GRB 231129A: optical upper limit in Mondy observatory
  60. GRB 231129C: AstroSat CZTI detection
  61. GRB 231129C: CALET Gamma-Ray Burst Monitor detection
  62. GRB 231129C: Fermi GBM Observation of a very bright GRB
  63. GRB 231129C: iTelescope likely optical afterglow AT 2023yph discovery
  64. GRB 231129C: MAXI/GSC detection
  65. GRB 231129C: BALROG localization (Fermi Trigger / GRB 231129799)
  66. GRB 231129C: Fermi GBM detection of a very bright burst
  67. GRB 231129C: Fermi GBM Final Real-time Localization
  68. Fermi trigger No 722977823: Global MASTER-Net observations report
  69. GRB 231129B: MAXI/GSC detection
  70. Integral GRB231129.21: Global MASTER-Net observations report
  71. LIGO/Virgo/KAGRA S231129ac: Identification of a GW compact binary merger candidate
  72. Fermi trigger No 722507896: Global MASTER-Net observations report
  73. Fermi trigger No 722462310: Global MASTER-Net observations report
  74. Fermi trigger No 722349867: Global MASTER-Net observations report
  75. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  76. GRB 231118A: Fermi GBM Final Real-time Localization
  77. LIGO/Virgo/KAGRA S231118ab: Identification of a GW compact binary merger candidate
  78. GRB 231117A: AKO Optical Upper Limit
  79. Swift GRB 231117A: Global MASTER-Net observations report
  80. GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
  81. GRB 231115A : MITSuME Akeno and Okayama optical upper limits
  82. GRB 231115A: archival HST observations
  83. GECAM-B observation of a short burst from SGR J1555-5402
  84. SGRJ1555-5402: Swift/BAT-GUANO arcminute localization of a SGR flare
  85. GRB 231111A: GMG observation (correction)
  86. GRB 231111A: GMG observation upper limit
  87. Fermi GRB 231108A: Global MASTER-Net observations report
  88. Fermi GRB 231106A: Global MASTER-Net observations report
  89. GRB 231104A: 3.6m DOT optical upper limit
  90. Fermi GRB 231103A: Global MASTER-Net observations report
  91. GRB 231104A: Fermi-LAT detection
  92. LIGO/Virgo/KAGRA S231104ac: Identification of a GW compact binary merger candidate
  93. IceCube Alert 231103.39: Global MASTER-Net observations report
  94. Fermi trigger No 720498201: Global MASTER-Net observations report
  95. GRB 231024A: AKO Optical Counterpart Candidate
  96. Fermi GRB 231030A: Global MASTER-Net observations report
  97. LIGO/Virgo/KAGRA S231029y: One counterpart neutrino candidate from IceCube neutrino searches
  98. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  99. LIGO/Virgo/KAGRA S231029y: Identification of a GW compact binary merger candidate
  100. LIGO/Virgo/KAGRA S231029k: Global MASTER-Net observations report

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