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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 230529A: Fermi GBM Final Real-time Localization
  2. LIGO/Virgo S230525a: Global MASTER-Net observations report
  3. LIGO/Virgo S230522a: Global MASTER-Net observations report
  4. LIGO/Virgo/KAGRA S230522a: 2 counterpart neutrino candidates from IceCube neutrino searches
  5. LIGO/Virgo S230521k: Global MASTER-Net observations report
  6. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  7. LIGO/Virgo/KAGRA S230520ae: Identification of a GW compact binary merger candidate: End-to-End Test
  8. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  9. GRB 230520A: MAXI/GSC detection
  10. LIGO/Virgo/KAGRA S230518h: AstroSat CZTI non-detection and upper limits
  11. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  12. GRB 230512A: Kitab possible afterglow candidate
  13. Fermi trigger No 705565670: Global MASTER-Net observations report
  14. GRB 230506C: SAO RAS optical observations
  15. GRB 230506B: MASTER optical observations
  16. IceCube-Cascade 230430A: Upper limits from a search for additional neutrino events in IceCube
  17. GRB 230426A: VZLUSAT-2 detection
  18. GRB 230426A: AstroSat CZTI detection
  19. Fermi trigger No 704233744: Global MASTER-Net observations report
  20. GRB 230414B: 3.6m DOT Optical observations, slow decay at early epochs
  21. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  22. GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  23. Fermi GRB 230414A: Global MASTER-Net observations report
  24. Fermi trigger No 702745263: Global MASTER-Net observations report
  25. GRB 230404A: AstroSat CZTI detection
  26. Fermi GRB 230402A: Global MASTER-Net observations report
  27. IceCube-Cascade 230329A: Upper limits from a search for additional neutrino events in IceCube
  28. GRB 230328B: 3.6m DOT multiband optical observation
  29. Konus-Wind detection of GRB 230328B
  30. GRB 230330A: Fermi GBM Final Real-time Localization
  31. GRB 230328B: Nanshan/NEXT 2nd optical observation
  32. GRB 230328B: Liverpool Telescope afterglow detection
  33. Fermi trigger No 701313046: Global MASTER-Net observations report
  34. Konus-Wind detection of GRB 230309A
  35. Fermi trigger No 701071944: Global MASTER-Net observations report
  36. SGR 1806-20: Correction to GCN 33494
  37. INTEGRAL detection of a burst from SGR 1806-200
  38. GRB 230314A: TURBO Optical Upper Limit
  39. Fermi GRB 230316A: Global MASTER-Net observations report
  40. VZLUSAT-2 detection of SGR 1806-20
  41. Alert from the HAWC Burst Monitor HAWC-230311A
  42. Trigger 1159327: Swift detection of SGR1806-20
  43. Fermi GRB 230310A: Global MASTER-Net observations report
  44. GRB 230228A: VIRT Optical Upper Limit
  45. Improved IPN localization for GRB 230307A
  46. IceCube Alert 230306.46: Global MASTER-Net observations report
  47. GRB 230228A: Swift-BAT refined analysis
  48. Fermi trigger No 699294715: Global MASTER-Net observations report
  49. GRB 230228A: Swift detection of a possibly short burst
  50. Fermi trigger No 699029364: Global MASTER-Net observations report
  51. GRB 230220A: MAXI/GSC detection
  52. IceCube Alert 230217.87: Global MASTER-Net observations report
  53. Fermi trigger No 697904388: Global MASTER-Net observations report
  54. Fermi GRB 230209B: Global MASTER-Net observations report
  55. ZTF23aabmzlp/AT2023azs: Neil Gehrels Swift Observatory X-ray observations
  56. GRB 230204B: 3.6m DOT optical observation
  57. GRB 230205A: Swift detection of a burst
  58. GRB 230204B: MAXI/GSC detection
  59. IceCube-230201A: Upper limits from a search for additional neutrino events in IceCube
  60. ZTF23aabmzlp/AT2023azs: Lulin 1m LOT optical observations
  61. ZTF23aabmzlp/AT2023azs: AMI-LA radio upper limit
  62. ZTF23aabmzlp/AT2023azs: LCOGT Optical Detection
  63. ZTF23aabmzlp/AT2023azs: Mondy and AbAO optical observations
  64. GRB 230129A: AstroSat CZTI detection
  65. GRB 230129A: Fermi GBM Final Real-time Localization
  66. GRB 230116D: 3.6m DOT optical upper limit
  67. Fermi-LAT Gamma-ray Observations of IceCube-Cascade-221229A
  68. GRB 230111A: MAXI/GSC detection
  69. IceCube-221223A: JCMT/SCUBA2 observations
  70. Fermi Gamma-ray Burst Monitor trigger 694043024/221229905 is not a GRB
  71. GRB 221231A: 3.6m DOT optical upper limit
  72. Subject: IceCube-Cascade 221229A: Upper limits from a search for additional neutrino events in IceCube
  73. IceCube-221229A: Upper limits from a search for additional neutrino events in IceCube
  74. Fermi-LAT gamma-ray observations of IceCube-221229A
  75. IceCube-221229A: BOOTES-2/TELMA Optical Upper Limit
  76. IceCube-221229A - IceCube observation of a high-energy neutrino candidate track-like event
  77. Fermi GRB 221226A: Global MASTER-Net observations report
  78. GRB 221218A: 3.6m DOT optical upper limit
  79. Fermi trigger No 692713692: Global MASTER-Net observations report
  80. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 December 13
  81. Fermi GRB 221211A: Global MASTER-Net observations report
  82. IceCube Alert 221210.36: Global MASTER-Net observations report
  83. GRB 221202A: VLT/FORS2 Afterglow Discovery
  84. GRB 221201A: Fermi GBM observation
  85. GRB 221126A: AGILE detection
  86. IceCube-221124A: BOOTES-4/MET and BOOTES-2/TELMA optical upper limit
  87. GRB 221126A: Swift/BAT-GUANO detection outside the coded FOV
  88. GRB 221126A: Fermi GBM Final Real-time Localization
  89. GRB 221120A: Detection by VZLUSAT-2
  90. IPN triangulation of GRB 221121A (long)
  91. GRB 221120A: Fermi GBM observation
  92. GRB 221120A: Swift detection of a likely short burst
  93. Konus-Wind detection of a burst from SGR 1935+2154 on 2022 November 9
  94. GRB 221110A: COATLI Afterglow detection
  95. GRB 221110A: Swift detection of a burst with an optical counterpart
  96. Swift GRB221110.10: Global MASTER-Net OT detection
  97. Swift GRB221110.10: Global MASTER-Net observations report
  98. Fermi-GBM Observations of High Bursting Activity from SGR J1935+2154
  99. GRB 221029A: CALET Gamma-Ray Burst Monitor detection
  100. GRB 221029A: Fermi GBM observation

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