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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').

9625 results found.

  1. Fermi GRB 240407A: Global MASTER-Net observations report
  2. Fermi-LAT gamma-ray observations of IceCube-240327B
  3. Fermi-LAT gamma-ray observations of IceCube-240327A
  4. GRB 240331A: GRBAlpha detection
  5. Konus-Wind detection of LXT 240402A/GRB 240402B
  6. LXT 240402A: MASTER optical observations with AGN in error-box
  7. Fermi GRB 240402A: Global MASTER-Net observations report
  8. X-ray transient EP240331a: Kinder optical upper limits
  9. X-ray transient EP240331A: GRANDMA-Kilonova catcher optical upper limit
  10. EP240331A: MASTER optical observations
  11. X-ray transient EP20240331a: MeerLICHT optical upper limits
  12. IceCube-240327B: Upper limits from a search for additional neutrino events in IceCube
  13. GRB 240324A: AstroSat CZTI detection of a short burst
  14. GRB 240331A: AstroSat CZTI detection
  15. GRB 240329A: AstroSat CZTI detection
  16. X-ray transient EP240315a: continued ATCA monitoring
  17. X-ray transient EP240315a: e-MERLIN radio observations
  18. GRB 240320A: Glowbug gamma-ray detection
  19. Fermi GRB 240320A: Global MASTER-Net observations report
  20. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  21. Fermi trigger No 732657380: Global MASTER-Net observations report
  22. GRB 240318A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  23. X-ray transient EP240315a: ATCA detection of radio counterpart
  24. GRB 240320A: Fermi GBM Final Real-time Localization
  25. IPN triangulation of GRB 240315C (consistent with a fast X-ray transient EP240315a)
  26. X-ray transient EP 240315a: Chandra observations
  27. GRB 240317C: Glowbug gamma-ray detection
  28. X-ray transient EP240315a: PRIME near infrared detection
  29. Fermi GRB 240318A: Global MASTER-Net observations report
  30. GRB 240317A: AstroSat CZTI detection
  31. GRB 240315B: AstroSat CZTI detection
  32. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  33. Fermi GRB 240317B: Global MASTER-Net observations report
  34. Fermi trigger No 732299243: Global MASTER-Net observations report
  35. Fermi GRB 240314A: Global MASTER-Net observations report
  36. GRB 240312A: GECAM detection of a long burst
  37. GRB 240303C: VZLUSAT-2 detection
  38. Fermi trigger No 731839490: Global MASTER-Net observations report
  39. Fermi-LAT gamma-ray observations of IceCube-240307A
  40. Fermi GRB 240310A: Global MASTER-Net observations report
  41. GRB 240309A: MAXI/GSC detection
  42. Fermi trigger No 731571927: Global MASTER-Net observations report
  43. Konus-Wind detection of GRB 231118A
  44. GRB 240306A: AstroSat CZTI detection
  45. Fermi GRB 240306A: Global MASTER-Net observations report
  46. Fermi GRB 240305A: Global MASTER-Net observations report
  47. GRB 240306A: Swift/BAT-GUANO detection of a burst
  48. Fermi-LAT gamma-ray observations of IceCube-240229A
  49. GRB 240305C: AstroSat CZTI detection of a short burst
  50. Fermi GRB 240305C: Global MASTER-Net observations report
  51. Konus-Wind detection of GRB 240227A (short/hard)
  52. Swift Trigger 1218701: Yes, we triggered on Swift J151857.0-572147 again
  53. Swift Trigger 1218696: Another trigger on Swift J151857.0-572147
  54. Konus-Wind detection of GRB 240303B
  55. GRB 240303B: Fermi GBM Detection
  56. GRB 240225B: Swift-XRT afterglow detection
  57. Fermi trigger No 731161136: Global MASTER-Net observations report
  58. GRB 240303C: BALROG localization (Fermi Trigger 731189113 / GRB 240303837)
  59. GRB 240225B: Glowbug gamma-ray detection
  60. GRB 240225A (short): Glowbug gamma-ray detection
  61. Konus-Wind detection of GRB 240225B (long)
  62. GRB 240225B: SAO RAS optical observations
  63. IPN triangulation of GRB 240227A (short)
  64. GRB 240225B: Liverpool Telescope optical afterglow observations
  65. GRB 240225B: CALET Gamma-Ray Burst Monitor detection
  66. Transient EPW20240219aa: REM optical/NIR upper limits
  67. GRB 240225B: AstroSat CZTI detection
  68. GRB 240225B: MAXI/GSC detection
  69. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  70. Transient EPW20240219aa: 7DT Optical Upper Limits
  71. VLA X-band observation of EPW20240219aa
  72. Transient EPW20240219aa: Mondy optical observations
  73. Transient EPW20240219aa: Liverpool Telescope non-detection and limiting magnitude
  74. GRB 240222A: Swift detection of a burst
  75. Swift GRB240221.92: Global MASTER-Net observations report
  76. GRB 240215B: Fermi GBM Observation
  77. GRB 240218A: LBT H-band detection
  78. Fermi GRB 240220A: Global MASTER-Net observations report
  79. GRB 240220A: Fermi GBM Final Real-time Localization
  80. Konus-Wind detection of GRB 240218A
  81. GRB 240218A: Swift-XRT refined Analysis
  82. GRB 240218A: Fermi GBM Detection
  83. IPN triangulation of GRB 240209A
  84. Fermi trigger No 729914426: Global MASTER-Net observations report
  85. Gamma-ray flaring activity from the blazar 1ES 1959+650 observed by the Fermi-LAT
  86. GRB 240213A: GRBAlpha detection
  87. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  88. GRB 240213A: Glowbug gamma-ray detection
  89. GRB240209A: OHP/T193 detection of the GOTO afterglow candidate AT2024cew / GOTO24pw
  90. GRB 240214A/1H 0451-560: MAXI/GSC detection
  91. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  92. Fermi GRB 240213A: Global MASTER-Net observations report
  93. GRB 240213A: Fermi GBM Final Real-time Localization
  94. Konus-Wind detection of GRB 240204A
  95. Konus-Wind detection of GRB 240205A (short)
  96. Fermi trigger No 729152364: Global MASTER-Net observations report
  97. IPN triangulation of GRB 240205A (short)
  98. Fermi-LAT gamma-ray observations of IceCube-240204A
  99. GRB 240205A (short): Glowbug gamma-ray detection
  100. GRB 240205B: AstroSat CZTI detection

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