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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').

2982 results found.

  1. GRB 230228A: OSN optical upper limit
  2. Fermi trigger No 699311646: Global MASTER-Net observations report
  3. GRB 230228A: Mondy optical upper limit
  4. GRB 230228A: Enhanced Swift-XRT position
  5. GRB 230228A: Nanshan/NEXT optical upper limit
  6. GRB 230228A: Miryang Arirang Astronomical Observatory (MAAO) 0.7-m telescope optical upper limit
  7. GRB 230228A: Prompt enhanced Swift-XRT position
  8. GRB 230228A: Swift detection of a possibly short burst
  9. Fermi GRB 230227A: Global MASTER-Net observations report
  10. Fermi trigger No 699029364: Global MASTER-Net observations report
  11. GRB 230217A: VLT/FORS2 optical observations and candidate counterpart
  12. GRB 230205A: VLA radio afterglow confirmation
  13. GRB 230220A: Correction to GCN 33352
  14. GRB 230217A: 6 GHz VLA observations
  15. GRB 230220A: MAXI/GSC detection
  16. GRB 230217A: Swift-XRT observations
  17. IceCube Alert 230217.87: Global MASTER-Net observations report
  18. Fermi trigger No 697678542: Global MASTER-Net observations report
  19. GRB 230205A: 6 GHz VLA observations
  20. GRB 230209A is not a GRB
  21. GRB 230205A: SUBARU HSC pre-imaging for host galaxy search
  22. GRB 230209A: Fermi GBM Final Real-time Localization
  23. GRB 230205A: possible host galaxy detection with the Schmidt - Asiago telescope
  24. Fermi trigger No 697098930: Global MASTER-Net observations report
  25. ZTF23aabmzlp/AT2023azs: Lulin 1m LOT optical observations
  26. ZTF23aaarlti/AT2023avj: Assy continued optical observations
  27. ZTF23aabmzlp/AT2023azs: 1.3m DFOT optical observations
  28. GRB 230128A: AstroSat CZTI detection
  29. ZTF23aaarlti/AT2023avj: VLA radio detection
  30. GRB 230128A: Fermi GBM Final Real-time Localization
  31. ZTF23aabmzlp/AT2023azs: Zwicky Transient Facility discovery of a fast optical transient
  32. Fermi GRB 230124A: Global MASTER-Net observations report
  33. Fermi GRB 230118A: Global MASTER-Net observations report
  34. Subject: IceCube-Cascade 221229A: Upper limits from a search for additional neutrino events in IceCube
  35. IceCube-221229A: Upper limits from a search for additional neutrino events in IceCube
  36. GRB 221228A: Fermi GBM Final Real-time Localization
  37. IceCube Alert 221223.32: Global MASTER-Net observations report
  38. GRB 221216A: Detection by VZLUSAT-2
  39. Fermi trigger No 692713692: Global MASTER-Net observations report
  40. Fermi Gamma-ray Burst Monitor triggers 692721536/221214610 and 692713692/221214520 are not GRBs
  41. Fermi GRB 221211A: Global MASTER-Net observations report
  42. IceCube Alert 221210.36: Global MASTER-Net observations report
  43. GRB 221202A: MeerLICHT upper limits
  44. Swift GRB 221201A: Global MASTER-Net observations report
  45. Alert from the HAWC Burst Monitor HAWC-221128A
  46. GRB 221120A: Detection by VZLUSAT-2
  47. Alert from the HAWC Burst Monitor HAWC-221123A
  48. GRB 221120A: AKO Telescope Upper Limits
  49. GRB 221120A: GIT upper limits on optical afterglow
  50. GRB 221120A: Swift detection of a likely short burst
  51. LAT GRB221119.63: Global MASTER-Net observations report
  52. GRB 221115A: Swift/BAT-GUANO detection
  53. GRB 221110A: GRANDMA observations
  54. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 November 9
  55. GRB 221110A: COATLI Second-Epoch Upper Limits
  56. GRB 221110A: GMG upper limit
  57. GRB 221110A: Swift detection of a burst with an optical counterpart
  58. GRB 221028A: Detection by VZLUSAT-2
  59. GRB 221028A: 1.3m DFOT Optical upper limit
  60. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  61. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  62. GRB 221029A: Detection by GRBAlpha
  63. GRB 221028A: CrAO/ZTSh optical upper limit
  64. GRB 221028A: AGILE detection
  65. GRB 221028A: MITSuME Okayama optical upper limits
  66. GRB 221028A: LCOGT Optical Upper Limits
  67. GRB 221027B: COATLI Upper Limits
  68. Swift GRB 221028A: Global MASTER-Net observations report
  69. GRB 221028A: BOOTES-4/MET optical upper limit
  70. GRB 221027B: FRAM-ORM and Ondrejov SBT optical limits
  71. Swift GRB 221027B: Global MASTER-Net observations report
  72. IPN triangulation of GRB 221022C (short)
  73. GRB 221023A: AGILE/GRID analysis
  74. IPN triangulation of GRB 221022B (long)
  75. GRB 221024A: Swift detection of a burst
  76. Fermi GBM trigger 687320613 / 221013100 (GRB 221013B) is not a GRB
  77. GRB 221013B: Swift/BAT-GUANO detection
  78. SGR 1935+2154: Bursting activity detected by VZLUSAT-2
  79. IPN triangulation of GRB 221017A (long)
  80. MAXI GRB221017.24: Global MASTER-Net observations report
  81. MAXI GRB 221006A: Redshifts of the possible host galaxies
  82. GRB 221013B: Fermi GBM Final Real-time Localization
  83. Integral GRB221012.98: Global MASTER-Net observations report
  84. Afterglow limits of GRB 221006A from OHP
  85. Fermi trigger No 687205006: Global MASTER-Net observations report
  86. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  87. INTEGRAL detection of a burst from SGR J1935+2154
  88. Konus-Wind detection of GRB 221009A
  89. GRB221009A/Swift J1913.1+1946: ATA follow-up observations
  90. GRB 221006A: Swift-XRT observations
  91. GRB 220921A: ATCA detection of radio counterpart
  92. Fermi trigger No 686403226: Global MASTER-Net observations report
  93. Fermi trigger No 686350260: Global MASTER-Net observations report
  94. Fermi-LAT gamma-ray observations of IceCube-220928A
  95. IceCube-220928A: Upper limits from a search for additional neutrino events in IceCube
  96. IceCube-220928A - IceCube observation of a high-energy neutrino candidate track-like event
  97. IPN triangulation of GRB 220927A (long)
  98. Fermi GRB 220925A: Global MASTER-Net observations report
  99. Fermi trigger No 685748699: Global MASTER-Net observations report
  100. LAT GRB220921.46: Global MASTER-Net observations report

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