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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.

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

23721 results found.

  1. EP240408a: Upper limits from GECAM-B Observation
  2. EP240408a: Swift follow-up observation
  3. EP240408a: BOOTES-6/DPRT optical upper limit
  4. GRB 240405A: GRBAlpha detection
  5. EP240408a: EP-WXT detection of a fast X-ray transient
  6. Swift Trigger 1220736: detection of 4U 1543-62.
  7. GRB 240408B: AstroSat CZTI detection
  8. IceCube-240327B: GRANDMA/Kilonova-Catcher observations of 4FGL J0555.9+0030 and optical upper limits
  9. Fermi GRB 240408A: Global MASTER-Net observations report
  10. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  11. Fermi GRB 240407A: Global MASTER-Net observations report
  12. LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation
  13. Fermi GRB 240405B: Global MASTER-Net observations report
  14. GRB 240402C: Glowbug gamma-ray detection
  15. GRB 240402C: GRBAlpha detection
  16. GRB 240331A: GRBAlpha detection
  17. Swift satellite resumes pointed science observations
  18. GRB 240403B: Glowbug gamma-ray detection
  19. GRB 240403A: Glowbug gamma-ray detection
  20. LXT 240402A/GRB 240402B: Glowbug gamma-ray detection
  21. Konus-Wind detection of LXT 240402A/GRB 240402B
  22. GRB/FXT 240402B: Kinder optical counterpart candidate
  23. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  24. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  25. LXT 240402A: EP-FXT detection of the X-ray afterglow
  26. Fermi GRB 240404A: Global MASTER-Net observations report
  27. LXT 240402A: MASTER optical observations with AGN in error-box
  28. X-ray transient LXT 240402A: LEIA detection
  29. Fermi trigger No 733808041: Global MASTER-Net observations report
  30. Fermi GRB 240402A: Global MASTER-Net observations report
  31. X-ray transient EP240331a: Kinder optical upper limits
  32. X-ray transient EP240331A: GRANDMA-Kilonova catcher optical upper limit
  33. EP240331A: MASTER optical observations
  34. Integral GRB240401.69: Global MASTER-Net observations report
  35. GRB 240329A: Glowbug gamma-ray detection
  36. GRB 240331A: AstroSat CZTI detection
  37. GRB 240329A: AstroSat CZTI detection
  38. GRB 240329A: GRBAlpha detection
  39. Fermi trigger No 733366352: Global MASTER-Net observations report
  40. Fermi GRB 240329A: Global MASTER-Net observations report
  41. Fermi GRB 240328B: Global MASTER-Net observations report
  42. Fermi GRB 240328A: Global MASTER-Net observations report
  43. GRB 240328C: Glowbug gamma-ray detection
  44. IceCube Alert 240327.68: Global MASTER-Net observations report
  45. X-ray transient EP 240315a: Second epoch Chandra observations
  46. Fermi trigger No 733097506: Global MASTER-Net observations report
  47. Transient EPW20240219aa: REM optical/NIR further observations
  48. Fermi trigger No 733092476: Global MASTER-Net observations report
  49. GRB 240320A: Glowbug gamma-ray detection
  50. Fermi trigger No 732937833: Global MASTER-Net observations report
  51. Fermi GRB 240320A: Global MASTER-Net observations report
  52. Konus-Wind detection of GRB 240315C (possible counterpart of EP240315a)
  53. Fermi trigger No 732657380: Global MASTER-Net observations report
  54. X-ray transient EP 240315a: Chandra observations
  55. X-ray transient EP240315a: GTC/HiPERCAM photometry
  56. X-ray transient EP240315a: GTC/OSIRIS spectroscopic redshift confirmation
  57. GRB 240318A: Glowbug gamma-ray detection
  58. GRB 240317C: Glowbug gamma-ray detection
  59. GRB 240318B: Glowbug gamma-ray detection
  60. X-ray transient EP240315a: 3.6 m TNG NIR detection
  61. Fermi GRB 240318A: Global MASTER-Net observations report
  62. GRB 240317A: AstroSat CZTI detection
  63. GRB 240315B: AstroSat CZTI detection
  64. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  65. Fermi GRB 240317B: Global MASTER-Net observations report
  66. Fermi GRB 240317A: Global MASTER-Net observations report
  67. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  68. Fermi trigger No 732299243: Global MASTER-Net observations report
  69. AT2024eju: followup observations with Liverpool Telescope suggest a fading transient
  70. X-ray transient EP240315a: ATLAS detection of a possible optical counterpart AT2024eju
  71. Einstein Probe detected of a fast X-ray transient EP240315a
  72. Fermi GRB 240314A: Global MASTER-Net observations report
  73. GRB 240312A: Glowbug gamma-ray detection
  74. GRB 240312A: GECAM detection of a long burst
  75. GRB 240303C: VZLUSAT-2 detection
  76. GRB 240310A: MASTER OT J200702.72-263928.7 inside 3sigma
  77. Fermi trigger No 731839490: Global MASTER-Net observations report
  78. GRB 240310B: Glowbug gamma-ray detection
  79. Fermi GRB 240310A: Global MASTER-Net observations report
  80. Swift GRB240309.61: Global MASTER-Net observations report
  81. GRB 240309A: MAXI/GSC detection
  82. Fermi trigger No 731571927: Global MASTER-Net observations report
  83. GRB 231215A: further radio observations with the VLA
  84. GRB 240229A: Glowbug gamma-ray detection
  85. GRB 240227A (short): Glowbug gamma-ray detection
  86. IceCube Alert 240307.32: Global MASTER-Net observations report
  87. GRB 240229A: GRBAlpha detection
  88. Konus-Wind detection of GRB 231118A
  89. Fermi GRB 240306A: Global MASTER-Net observations report
  90. Fermi GRB 240305A: Global MASTER-Net observations report
  91. GRB 240306A: Fermi GBM Final Real-time Localization
  92. Swift GRB240305.18: Global MASTER-Net observations report
  93. Swift GRB240305.16: Global MASTER-Net observations report
  94. Fermi GRB 240305C: Global MASTER-Net observations report
  95. GRB 231028C: Glowbug gamma-ray confirmation of a prior burst
  96. Fermi trigger No 731303574: Global MASTER-Net observations report
  97. Konus-Wind detection of GRB 240227A (short/hard)
  98. GRB 240303B: VZLUSAT-2 detection
  99. GRB 240229A: VZLUSAT-2 detection
  100. Improved IPN triangulation of GRB 240227A (short)

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