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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"

36177 results found.

  1. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  2. GRB 240514A: Fermi GBM Final Real-time Localization
  3. GRB 240513A: Tiled Swift observations
  4. GRB 240513A: Fermi-LAT detection
  5. GRB 240511A: Fermi GBM Observation
  6. GRB 240511A: Swift-BAT refined analysis
  7. Fermi GRB 240513B: Global MASTER-Net observations report
  8. GRB 240513B: Fermi GBM Final Real-time Localization
  9. GRB 240513A: AstroSat CZTI detection
  10. GRB 240511A: J-band observations with WINTER
  11. GRB 240511A: Enhanced Swift-XRT position
  12. GRB 240511A : MITSuME Akeno optical upper limits
  13. GRB 240511A: Swift-XRT refined Analysis
  14. GRB 240511A: optical afterglow detection from the NOT
  15. Fermi Gamma-ray Burst Monitor trigger 737102480/240511279 is not a GRB
  16. Fermi Gamma-ray Burst Monitor trigger 737111207/240511380 is not a GRB
  17. Fermi GBM trigger 737105243/240511311 is not a GRB
  18. Fermi GRB 240511A: Global MASTER-Net observations report
  19. Swift GRB 240511A: Global MASTER-Net observations report
  20. Fermi Gamma-ray Burst Monitor trigger 737133200/240511634 is not a GRB
  21. GRB 240511A: Prompt enhanced Swift-XRT position
  22. GRB 240511A: Swift detection of a burst
  23. GRB 240511A: Fermi GBM Final Real-time Localization
  24. Fermi Gamma-ray Burst Monitor trigger 737076431/240510977 is not a GRB
  25. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  26. EP240506a: CrAO ZTSH optical upper limit
  27. GRB 240504A: Fermi GBM Observation
  28. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  29. IPN triangulation of GRB 240504A
  30. GRB 240502A: 1.3m DFOT Optical upper limit
  31. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  32. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  33. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  34. Fermi GRB 240504A: Global MASTER-Net observations report
  35. GRB 240503A: AstroSat CZTI detection
  36. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  37. GRB 240504A: Fermi GBM Final Real-time Localization
  38. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  39. GRB 240502A: GOTO optical upper limit
  40. GRB 240502A: Fermi GBM Observation
  41. GRB 240415A 1.3m DFOT Optical upper limit
  42. GRB 240502C: GOTO possible optical counterpart candidates
  43. Fermi GRB 240502B: Global MASTER-Net observations report
  44. GRB 240502C: Fermi GBM Final Localization
  45. Fermi GRB 240502A: Global MASTER-Net observations report
  46. GRB 240501B: GRBAlpha detection
  47. GRB 240430A: GRBAlpha detection
  48. GRB 240502B: Fermi GBM Final Real-time Localization
  49. GRB 240502A long GRB detected by INTEGRAL
  50. GRB 240502A: Fermi GBM Final Real-time Localization
  51. Fermi GRB 240501A: Global MASTER-Net observations report
  52. GRB 240426A: VZLUSAT-2 detection
  53. GRB 240425A: VZLUSAT-2 detection
  54. GRB240430A: Fermi GBM Final Localization
  55. GRB 240501B: AstroSat CZTI detection
  56. GRB 240501A: Fermi GBM Final Real-time Localization
  57. GRB 240408B: VZLUSAT-2 detection
  58. GRB 240407A: VZLUSAT-2 detection
  59. X-ray transient EP240414a: Detection of associated supernova
  60. GRB 240425A: GRBAlpha detection
  61. GRB 240429A: Fermi GBM Final Real-time Localization
  62. Fermi GRB 240428A: Global MASTER-Net observations report
  63. GRB 240428A: Fermi GBM Final Real-time Localization
  64. GRB 240426A: AstroSat CZTI detection
  65. GRB 240414A: NOEMA detection
  66. LIGO/Virgo/KAGRA S240422ed: Upper limits from GECAM Observations
  67. GRB 240425A: Fermi GBM Final Real-time Localization
  68. GRB 240419B: Swift-BAT refined analysis
  69. GRB 240421B: Swift-BAT refined analysis
  70. GRB 240422A: Glowbug gamma-ray detection
  71. IceCube-240424A - IceCube observation of a high-energy neutrino candidate track-like event
  72. GRB 240421B: GRBAlpha detection
  73. GRB 240419A: Swift-BAT refined analysis
  74. GRB 240418A: Swift-BAT refined analysis
  75. LXT240402A/GRB240402B: Chandra X-ray detection
  76. GRB 240419A: Possible ATCA radio detection
  77. GRB 240421B: ATCA radio observations
  78. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  79. LIGO/Virgo/KAGRA S240422ed: AstroSat CZTI non-detection and upper limits
  80. LIGO/Virgo/KAGRA S240422ed: Upper limits from Fermi-GBM Observations
  81. LIGO/Virgo/KAGRA S240421ar: Upper limits from Swift/BAT-GUANO
  82. GRB 240421A: Glowbug gamma-ray detection
  83. GRB 240414A: radio detection with the VLA
  84. GRB 240414A: AMI-LA radio observations
  85. GRB 240414A: LBT optical detection
  86. GRB 240419B : MITSuME Akeno optical upper limits
  87. GRB 240415B: Swift-XRT observations
  88. GRB 240415A: Swift-XRT refined Analysis
  89. Fermi GRB 240422A: Global MASTER-Net observations report
  90. GRB 240421B: AstroSat CZTI detection
  91. GRB 240422A: Fermi GBM Final Real-time Localization
  92. GRB240421B: Zadko Observations
  93. Fermi GRB 240421B: Global MASTER-Net observations report
  94. Swift GRB 240421B: Global MASTER-Net observations report
  95. GRB 240421B: Fermi GBM Observation
  96. GRB 240421B: Swift-XRT refined Analysis
  97. GRB240421B: BOOTES-5/JGT optical upper limit
  98. GRB 240421B: J-band upper limits from WINTER
  99. GRB 240421B: Swift/UVOT Upper Limits
  100. GRB 240421B: Enhanced Swift-XRT position

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