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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"

23727 results found.

  1. GRB 240411A: GRBAlpha detection
  2. GRB 240405A: Glowbug gamma-ray detection
  3. GRB 240411B: LCO optical afterglow detection
  4. GRB 240411B: Swift detection of a burst
  5. GRB 240408B: GRBAlpha detection
  6. EP240408A: MASTER optical observations
  7. EP240408a: Upper limits from GECAM-B Observation
  8. EP240408a: Swift follow-up observation
  9. EP240408a: BOOTES-6/DPRT optical upper limit
  10. GRB 240405A: GRBAlpha detection
  11. EP240408a: EP-WXT detection of a fast X-ray transient
  12. Swift Trigger 1220736: detection of 4U 1543-62.
  13. GRB 240408B: AstroSat CZTI detection
  14. IceCube-240327B: GRANDMA/Kilonova-Catcher observations of 4FGL J0555.9+0030 and optical upper limits
  15. Fermi GRB 240408A: Global MASTER-Net observations report
  16. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  17. Fermi GRB 240407A: Global MASTER-Net observations report
  18. LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation
  19. Fermi GRB 240405B: Global MASTER-Net observations report
  20. GRB 240402C: Glowbug gamma-ray detection
  21. GRB 240402C: GRBAlpha detection
  22. GRB 240331A: GRBAlpha detection
  23. Swift satellite resumes pointed science observations
  24. GRB 240403B: Glowbug gamma-ray detection
  25. GRB 240403A: Glowbug gamma-ray detection
  26. LXT 240402A/GRB 240402B: Glowbug gamma-ray detection
  27. Konus-Wind detection of LXT 240402A/GRB 240402B
  28. GRB/FXT 240402B: Kinder optical counterpart candidate
  29. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  30. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  31. LXT 240402A: EP-FXT detection of the X-ray afterglow
  32. Fermi GRB 240404A: Global MASTER-Net observations report
  33. LXT 240402A: MASTER optical observations with AGN in error-box
  34. X-ray transient LXT 240402A: LEIA detection
  35. Fermi trigger No 733808041: Global MASTER-Net observations report
  36. Fermi GRB 240402A: Global MASTER-Net observations report
  37. X-ray transient EP240331a: Kinder optical upper limits
  38. X-ray transient EP240331A: GRANDMA-Kilonova catcher optical upper limit
  39. EP240331A: MASTER optical observations
  40. Integral GRB240401.69: Global MASTER-Net observations report
  41. GRB 240329A: Glowbug gamma-ray detection
  42. GRB 240331A: AstroSat CZTI detection
  43. GRB 240329A: AstroSat CZTI detection
  44. GRB 240329A: GRBAlpha detection
  45. Fermi trigger No 733366352: Global MASTER-Net observations report
  46. Fermi GRB 240329A: Global MASTER-Net observations report
  47. Fermi GRB 240328B: Global MASTER-Net observations report
  48. Fermi GRB 240328A: Global MASTER-Net observations report
  49. GRB 240328C: Glowbug gamma-ray detection
  50. IceCube Alert 240327.68: Global MASTER-Net observations report
  51. X-ray transient EP 240315a: Second epoch Chandra observations
  52. Fermi trigger No 733097506: Global MASTER-Net observations report
  53. Transient EPW20240219aa: REM optical/NIR further observations
  54. Fermi trigger No 733092476: Global MASTER-Net observations report
  55. GRB 240320A: Glowbug gamma-ray detection
  56. Fermi trigger No 732937833: Global MASTER-Net observations report
  57. Fermi GRB 240320A: Global MASTER-Net observations report
  58. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  59. Fermi trigger No 732657380: Global MASTER-Net observations report
  60. X-ray transient EP 240315a: Chandra observations
  61. X-ray transient EP240315a: GTC/HiPERCAM photometry
  62. X-ray transient EP240315a: GTC/OSIRIS spectroscopic redshift confirmation
  63. GRB 240318A: Glowbug gamma-ray detection
  64. GRB 240317C: Glowbug gamma-ray detection
  65. GRB 240318B: Glowbug gamma-ray detection
  66. X-ray transient EP240315a: 3.6 m TNG NIR detection
  67. Fermi GRB 240318A: Global MASTER-Net observations report
  68. GRB 240317A: AstroSat CZTI detection
  69. GRB 240315B: AstroSat CZTI detection
  70. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  71. Fermi GRB 240317B: Global MASTER-Net observations report
  72. Fermi GRB 240317A: Global MASTER-Net observations report
  73. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  74. Fermi trigger No 732299243: Global MASTER-Net observations report
  75. AT2024eju: followup observations with Liverpool Telescope suggest a fading transient
  76. X-ray transient EP240315a: ATLAS detection of a possible optical counterpart AT2024eju
  77. Einstein Probe detected of a fast X-ray transient EP240315a
  78. Fermi GRB 240314A: Global MASTER-Net observations report
  79. GRB 240312A: Glowbug gamma-ray detection
  80. GRB 240312A: GECAM detection of a long burst
  81. GRB 240303C: VZLUSAT-2 detection
  82. GRB 240310A: MASTER OT J200702.72-263928.7 inside 3sigma
  83. Fermi trigger No 731839490: Global MASTER-Net observations report
  84. GRB 240310B: Glowbug gamma-ray detection
  85. Fermi GRB 240310A: Global MASTER-Net observations report
  86. Swift GRB240309.61: Global MASTER-Net observations report
  87. GRB 240309A: MAXI/GSC detection
  88. Fermi trigger No 731571927: Global MASTER-Net observations report
  89. GRB 231215A: further radio observations with the VLA
  90. GRB 240229A: Glowbug gamma-ray detection
  91. GRB 240227A (short): Glowbug gamma-ray detection
  92. IceCube Alert 240307.32: Global MASTER-Net observations report
  93. GRB 240229A: GRBAlpha detection
  94. Konus-Wind detection of GRB 231118A
  95. Fermi GRB 240306A: Global MASTER-Net observations report
  96. Fermi GRB 240305A: Global MASTER-Net observations report
  97. GRB 240306A: Fermi GBM Final Real-time Localization
  98. Swift GRB240305.18: Global MASTER-Net observations report
  99. Swift GRB240305.16: Global MASTER-Net observations report
  100. Fermi GRB 240305C: Global MASTER-Net observations report

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