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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

45794 results found.

  1. X-ray transient LXT 240402A: LEIA detection
  2. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  3. Fermi trigger No 733808041: Global MASTER-Net observations report
  4. Fermi GRB 240402A: Global MASTER-Net observations report
  5. GRB 240402A: Fermi GBM Final Real-time Localization
  6. X-ray transient EP240331a: Kinder optical upper limits
  7. X-ray transient EP240331A: GRANDMA-Kilonova catcher optical upper limit
  8. EP240331A: MASTER optical observations
  9. Transient EP240315a: J-band observations of AT2024eju with WIRC
  10. X-ray transient EP20240331a: MeerLICHT optical upper limits
  11. IceCube-240327B: Upper limits from a search for additional neutrino events in IceCube
  12. IceCube-240327A: Upper limits from a search for additional neutrino events in IceCube
  13. Integral GRB240401.69: Global MASTER-Net observations report
  14. GRB 240329A: Glowbug gamma-ray detection
  15. GRB 240324A: AstroSat CZTI detection of a short burst
  16. GRB 240331A: AstroSat CZTI detection
  17. GRB 240329A: AstroSat CZTI detection
  18. GRB 240331A: Fermi GBM Final Real-time Localization
  19. GRB 240329A: GRBAlpha detection
  20. Fermi trigger No 733366352: Global MASTER-Net observations report
  21. Fermi GRB 240329A: Global MASTER-Net observations report
  22. GRB 240329A: BALROG localization (Fermi Trigger 733441392 / GRB 240329905)
  23. GRB 240329A: Fermi GBM Final Real-time Localization
  24. Fermi GRB 240328B: Global MASTER-Net observations report
  25. Fermi GRB 240328A: Global MASTER-Net observations report
  26. X-ray transient EP240315a: continued ATCA monitoring
  27. IceCube-240327B: No candidates from the Zwicky Transient Facility
  28. GRB 240328C: Glowbug gamma-ray detection
  29. GRB 240328B: Fermi GBM Final Real-time Localization
  30. GRB 240328A: Fermi GBM Final Real-time Localization
  31. IceCube Alert 240327.68: Global MASTER-Net observations report
  32. IceCube-240327B - IceCube observation of a high-energy neutrino candidate track-like event
  33. IceCube-240327A - IceCube observation of a high-energy neutrino candidate track-like event
  34. X-ray transient EP 240315a: Second epoch Chandra observations
  35. Fermi trigger No 733097506: Global MASTER-Net observations report
  36. X-ray transient EP240315a: e-MERLIN radio observations
  37. X-ray transient EP240315a: Ondrejov D50 optical limit
  38. Transient EPW20240219aa: REM optical/NIR further observations
  39. Fermi trigger No 733092476: Global MASTER-Net observations report
  40. GRB 240320A: Glowbug gamma-ray detection
  41. Fermi trigger No 732937833: Global MASTER-Net observations report
  42. GRB 240318A: Fermi GBM Observation
  43. Fermi GRB 240320A: Global MASTER-Net observations report
  44. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  45. Fermi trigger No 732657380: Global MASTER-Net observations report
  46. GRB 240318A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  47. X-ray transient EP240315a: ATCA detection of radio counterpart
  48. GRB 240320A: Fermi GBM Final Real-time Localization
  49. IPN triangulation of GRB 240315C (consistent with a fast X-ray transient EP240315a)
  50. GRB 240317B: Swift/BAT-GUANO Angular Error Correction
  51. Fermi Gamma-ray Burst Monitor trigger 732299243/240316686 is not a GRB
  52. X-ray transient EP 240315a: Chandra observations
  53. X-ray transient EP240315a: GTC/HiPERCAM photometry
  54. X-ray transient EP240315a: MeerKAT radio detection
  55. X-ray transient EP240315a: GTC/OSIRIS spectroscopic redshift confirmation
  56. GRB 240318A: Glowbug gamma-ray detection
  57. GRB 240317C: Glowbug gamma-ray detection
  58. GRB 240318B: Glowbug gamma-ray detection
  59. X-ray transient EP240315a: PRIME near infrared detection
  60. GRB 240317B: Fermi GBM Observation
  61. X-ray transient EP240315a: 3.6 m TNG NIR detection
  62. Swift satellite in safe mode
  63. X-ray transient EP240315a/AT2024eju: TShAO (Zeiss-1000) observatory optical upper limit
  64. X-ray transient EP240315a: EP-FXT detection of the X-ray afterglow
  65. Fermi GRB 240318A: Global MASTER-Net observations report
  66. GRB 240318A: Fermi GBM Final Real-time Localization
  67. GRB 240317B: Swift/BAT-GUANO arcminute localization of a burst
  68. GRB 240317A: AstroSat CZTI detection
  69. GRB 240315B: AstroSat CZTI detection
  70. X-ray transient EP240315a: Kitab observatory optical upper limitns
  71. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  72. Fermi GRB 240317B: Global MASTER-Net observations report
  73. Fermi GRB 240317A: Global MASTER-Net observations report
  74. GRB 240317B: Fermi GBM Final Real-time Localization
  75. X-ray transient EP240315a: orphan FXT?
  76. GRB 240317A: Fermi GBM Final Real-time Localization
  77. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  78. X-ray transient EP240315a: GROND J-band detection
  79. X-ray transient EP240315a: VLT/X-shooter spectroscopic redshift of z = 4.859
  80. X-ray transient EP240315a: Nanshan/HMT optical upper limit
  81. Fermi trigger No 732299243: Global MASTER-Net observations report
  82. AT2024eju: followup observations with Liverpool Telescope suggest a fading transient
  83. X-ray transient EP240315a: ATLAS detection of a possible optical counterpart AT2024eju
  84. Einstein Probe detected of a fast X-ray transient EP240315a
  85. GRID detection of GRB 240306A
  86. Changes to the Fermi-GBM Triggering Thresholds
  87. Swift Triggers 1220155, 1220156, 1220157, 1220158, 1220160 and 1220161 were not astrophysical
  88. GRB 240315A: Fermi GBM Final Real-time Localization
  89. Swift Triggers 1220093, 1220094, 1220095 and 1220096 are not astrophysical
  90. Swift Triggers 1220090, 1220091 and 1220092 are not astrophysical
  91. Fermi GRB 240314A: Global MASTER-Net observations report
  92. GRB 240314A: Fermi GBM Final Real-time Localization
  93. GRB240204A: VIRT optical upper limit
  94. GRB 240312A: Glowbug gamma-ray detection
  95. Swift triggers 1219917, 1219917 and 1219922 were not astrophysical
  96. Swift Trigger 1219909 and 1219910 are not a astrophysical
  97. Swift Trigger 1219905 is not a GRB
  98. GRB 240312A: GECAM detection of a long burst
  99. Swift Trigger 1219874 is not astrophysical
  100. GRB 240303C: VZLUSAT-2 detection

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