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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"

36182 results found.

  1. GRB 240514C: Fermi GBM Final Real-time Localization
  2. Fermi GRB 240514B: Global MASTER-Net observations report
  3. GRB 240514B: Fermi GBM Final Real-time Localization
  4. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  5. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  6. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  7. GRB 240514A: Fermi GBM Final Real-time Localization
  8. GRB 240513A: Tiled Swift observations
  9. GRB 240513A: Fermi-LAT detection
  10. GRB 240511A: Fermi GBM Observation
  11. GRB 240511A: Swift-BAT refined analysis
  12. Fermi GRB 240513B: Global MASTER-Net observations report
  13. GRB 240513B: Fermi GBM Final Real-time Localization
  14. GRB 240513A: AstroSat CZTI detection
  15. GRB 240511A: J-band observations with WINTER
  16. GRB 240511A: Enhanced Swift-XRT position
  17. GRB 240511A : MITSuME Akeno optical upper limits
  18. GRB 240511A: Swift-XRT refined Analysis
  19. GRB 240511A: optical afterglow detection from the NOT
  20. Fermi Gamma-ray Burst Monitor trigger 737102480/240511279 is not a GRB
  21. Fermi Gamma-ray Burst Monitor trigger 737111207/240511380 is not a GRB
  22. Fermi GBM trigger 737105243/240511311 is not a GRB
  23. Fermi GRB 240511A: Global MASTER-Net observations report
  24. Swift GRB 240511A: Global MASTER-Net observations report
  25. Fermi Gamma-ray Burst Monitor trigger 737133200/240511634 is not a GRB
  26. GRB 240511A: Prompt enhanced Swift-XRT position
  27. GRB 240511A: Swift detection of a burst
  28. GRB 240511A: Fermi GBM Final Real-time Localization
  29. Fermi Gamma-ray Burst Monitor trigger 737076431/240510977 is not a GRB
  30. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  31. EP240506a: CrAO ZTSH optical upper limit
  32. GRB 240504A: Fermi GBM Observation
  33. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  34. IPN triangulation of GRB 240504A
  35. GRB 240502A: 1.3m DFOT Optical upper limit
  36. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  37. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  38. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  39. Fermi GRB 240504A: Global MASTER-Net observations report
  40. GRB 240503A: AstroSat CZTI detection
  41. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  42. GRB 240504A: Fermi GBM Final Real-time Localization
  43. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  44. GRB 240502A: GOTO optical upper limit
  45. GRB 240502A: Fermi GBM Observation
  46. GRB 240415A 1.3m DFOT Optical upper limit
  47. GRB 240502C: GOTO possible optical counterpart candidates
  48. Fermi GRB 240502B: Global MASTER-Net observations report
  49. GRB 240502C: Fermi GBM Final Localization
  50. Fermi GRB 240502A: Global MASTER-Net observations report
  51. GRB 240501B: GRBAlpha detection
  52. GRB 240430A: GRBAlpha detection
  53. GRB 240502B: Fermi GBM Final Real-time Localization
  54. GRB 240502A long GRB detected by INTEGRAL
  55. GRB 240502A: Fermi GBM Final Real-time Localization
  56. Fermi GRB 240501A: Global MASTER-Net observations report
  57. GRB 240426A: VZLUSAT-2 detection
  58. GRB 240425A: VZLUSAT-2 detection
  59. GRB240430A: Fermi GBM Final Localization
  60. GRB 240501B: AstroSat CZTI detection
  61. GRB 240501A: Fermi GBM Final Real-time Localization
  62. GRB 240408B: VZLUSAT-2 detection
  63. GRB 240407A: VZLUSAT-2 detection
  64. X-ray transient EP240414a: Detection of associated supernova
  65. GRB 240425A: GRBAlpha detection
  66. GRB 240429A: Fermi GBM Final Real-time Localization
  67. Fermi GRB 240428A: Global MASTER-Net observations report
  68. GRB 240428A: Fermi GBM Final Real-time Localization
  69. GRB 240426A: AstroSat CZTI detection
  70. GRB 240414A: NOEMA detection
  71. LIGO/Virgo/KAGRA S240422ed: Upper limits from GECAM Observations
  72. GRB 240425A: Fermi GBM Final Real-time Localization
  73. GRB 240419B: Swift-BAT refined analysis
  74. GRB 240421B: Swift-BAT refined analysis
  75. GRB 240422A: Glowbug gamma-ray detection
  76. IceCube-240424A - IceCube observation of a high-energy neutrino candidate track-like event
  77. GRB 240421B: GRBAlpha detection
  78. GRB 240419A: Swift-BAT refined analysis
  79. GRB 240418A: Swift-BAT refined analysis
  80. LXT240402A/GRB240402B: Chandra X-ray detection
  81. GRB 240419A: Possible ATCA radio detection
  82. GRB 240421B: ATCA radio observations
  83. LIGO/Virgo S240422ed: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  84. LIGO/Virgo/KAGRA S240422ed: AstroSat CZTI non-detection and upper limits
  85. LIGO/Virgo/KAGRA S240422ed: Upper limits from Fermi-GBM Observations
  86. LIGO/Virgo/KAGRA S240421ar: Upper limits from Swift/BAT-GUANO
  87. GRB 240421A: Glowbug gamma-ray detection
  88. GRB 240414A: radio detection with the VLA
  89. GRB 240414A: AMI-LA radio observations
  90. GRB 240414A: LBT optical detection
  91. GRB 240419B : MITSuME Akeno optical upper limits
  92. GRB 240415B: Swift-XRT observations
  93. GRB 240415A: Swift-XRT refined Analysis
  94. Fermi GRB 240422A: Global MASTER-Net observations report
  95. GRB 240421B: AstroSat CZTI detection
  96. GRB 240422A: Fermi GBM Final Real-time Localization
  97. GRB240421B: Zadko Observations
  98. Fermi GRB 240421B: Global MASTER-Net observations report
  99. Swift GRB 240421B: Global MASTER-Net observations report
  100. GRB 240421B: Fermi GBM Observation

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