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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').

2983 results found.

  1. GRB 231230A: GOTO optical upper limits
  2. Fermi trigger No 725592555: Global MASTER-Net observations report
  3. Swift Triggers 1205103, 1205104, 1205107 and 1205110 are not astrophysical events
  4. LIGO/Virgo/KAGRA S231223j: Identification of a GW compact binary merger candidate
  5. Fermi trigger No 724781422: Global MASTER-Net observations report
  6. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  7. GRB 231216A: BOOTES-2/TELMA optical upper limit
  8. GRB 231214A: AstroSat CZTI detection
  9. Fermi trigger No 724278269: Global MASTER-Net observations report
  10. Fermi trigger No 724233240: Global MASTER-Net observations report
  11. GRB 231214A: Swift detection of a burst
  12. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  13. GRB 231129C: ASIM MXGS observation and localization
  14. Fermi trigger No 723435916: Global MASTER-Net observations report
  15. Fermi trigger No 723326169: Global MASTER-Net observations report
  16. Fermi trigger No 723149952: Global MASTER-Net observations report
  17. GRB 231128A: VZLUSAT-2 detection
  18. GRB 231129C: MAXI/GSC detection
  19. GRB 231128A: Fermi GBM Final Real-time Localization
  20. Fermi trigger No 722507896: Global MASTER-Net observations report
  21. GRB230728A: VIRT optical upper limit
  22. Fermi trigger No 722400249: Global MASTER-Net observations report
  23. GRB 231118A: MeerLICHT afterglow detection
  24. GRB 231115A: optical observations from INAF observatories
  25. GRB 231110A: Terskol Zeiss-2000 optical upper limit
  26. Swift GRB231110.89: Global MASTER-Net observations report
  27. Fermi GRB 231108A: Global MASTER-Net observations report
  28. Fermi trigger No 721006392: Global MASTER-Net observations report
  29. Fermi GRB 231106A: Global MASTER-Net observations report
  30. Fermi GRB 231103A: Global MASTER-Net observations report
  31. GRB 231104A: Fermi-LAT detection
  32. GRB 231104A: Swift detection of a bright burst
  33. GRB 231104A: Fermi GBM Final Real-time Localization
  34. Fermi trigger No 720498201: Global MASTER-Net observations report
  35. GRB 231028B: VZLUSAT-2 detection
  36. Fermi GRB 231030B: Global MASTER-Net observations report
  37. IceCube-231027A: Upper limits from a search for additional neutrino events in IceCube
  38. GRB 231028A: CALET Gamma-Ray Burst Monitor detection
  39. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  40. GRB 231028A: AstroSat CZTI detection
  41. GRB 231028A: Glowbug gamma-ray detection
  42. GRB 231028A: Fermi GBM Detection
  43. Fermi trigger No 720224759: Global MASTER-Net observations report
  44. Swift GRB 231028A: Global MASTER-Net observations report
  45. LIGO/Virgo/KAGRA S231028bg: Identification of a GW compact binary merger candidate
  46. GRB 231028A: Fermi GBM Final Real-time Localization
  47. IceCube Alert 231027.18: Global MASTER-Net observations report
  48. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  49. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  50. Fermi trigger No 719846439: Global MASTER-Net observations report
  51. Fermi GRB 231019A: Global MASTER-Net observations report
  52. Konus-Wind detection of GRB 231018A
  53. IPN triangulation of GRB 231018A
  54. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  55. IceCube-231004A: No significant detection in HAWC
  56. LIGO/Virgo/KAGRA S231005j: Identification of a GW compact binary merger candidate
  57. NuEm-230927A: Swift-XRT follow-up
  58. LIGO/Virgo/KAGRA S230928cb: Identification of a GW compact binary merger candidate
  59. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  60. IPN triangulation of GRB 230919A (short)
  61. GRB 230916A: NuSTAR Discovery of Prompt Emission from a Potential GRB
  62. Fermi trigger No 716449174: Global MASTER-Net observations report
  63. Fermi trigger No 716145795: Global MASTER-Net observations report
  64. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  65. Fermi GRB 230906A: Global MASTER-Net observations report
  66. GRB 230904C: Fermi GBM Final Localization
  67. Fermi trigger No 715429986: Global MASTER-Net observations report
  68. Fermi GRB 230903A: Global MASTER-Net observations report
  69. GRB 230828A: AstroSat CZTI detection
  70. GRB 230828A: GRBAlpha detection
  71. GRB 230827B / GRB 230827256: Fermi GBM Observation
  72. Fermi GRB 230827A: Global MASTER-Net observations report
  73. AT 2023qxj: ZTF discovery of the likely afterglow of Fermi GRB 230827256
  74. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  75. Integral GRB230824.72: Global MASTER-Net observations report
  76. Swift GRB230821.64: Global MASTER-Net observations report
  77. Swift Triggers 1186280 and 1186291 are not GRBs
  78. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  79. Fermi GRB 230818A: Global MASTER-Net observations report
  80. Swift GRB230818.98: Global MASTER-Net observations report
  81. Swift GRB230818.98: Global MASTER-Net OT detection
  82. Swift GRB230816.80: Global MASTER-Net observations report
  83. LAT GRB230812.79: Global MASTER-Net observations report
  84. Fermi trigger No 713525317: Global MASTER-Net observations report
  85. GRB 230812A: Fermi GBM Final Real-time Localization
  86. GRB 230805B : MITSuME Akeno optical upper limits
  87. transient SPT-SVJ025406.5-702837: ATCA follow-up observations
  88. Fermi trigger No 713134237: Global MASTER-Net observations report
  89. GRB 230803A: AstroSat CZTI detection
  90. IceCube-230724A: JCMT/SCUBA-2 submm observations
  91. IceCube-230707A: JCMT/SCUBA-2 submm observations
  92. GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G
  93. Fermi trigger No 712306969: Global MASTER-Net observations report
  94. IceCube-230727A: No candidates from the Zwicky Transient Facility
  95. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  96. GRB 230728A: BOOTES-1 optical upper limit
  97. GRB 230728A: Fermi GBM Observation
  98. GRB 230728A: LCOGT Optical Upper Limit
  99. GRB 230728A: NOT optical observations and possible host galaxy
  100. Swift GRB230728.12: Global MASTER-Net observations report

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