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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"

37768 results found.

  1. GRB 240417A: Fermi GBM Final Real-time Localization
  2. GRB 240415A: Glowbug gamma-ray detection
  3. GRB 240414A: Glowbug gamma-ray detection
  4. GRB 240415B: GECAM-B detection
  5. EP 240416a: Xinglong and NOT decaying optical counterpart
  6. GRB 240415A: Swift-BAT refined analysis
  7. GRB 240411A: Glowbug gamma-ray detection
  8. GRB 240414A: Swift-BAT refined analysis
  9. GRB 240414A: AbAO optical upprer limit
  10. GRB 240415A: Swift/UVOT Detection
  11. GRB 240415A: Fermi GBM Observation
  12. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  13. GRB 240415A: Earliest optical followup with the Kinder observations
  14. GRB 240414A: GMG observation
  15. GRB 240415A: Enhanced Swift-XRT position
  16. GRB 240415B: Swift ToO observations
  17. GRB 240415B: Swift/BAT-GUANO Correction
  18. GRB 240415B: Swift/BAT-GUANO arcminute localization of a short burst
  19. GRB 240415A: OHP/T193 optical observations
  20. GRB 240415A: optical afterglow detection from the INAF Asiago Observatory
  21. GRB 240415A: SAO RAS optical observations
  22. GRB 240415A: Mondy optical transient detection (photometry correction in GCN 36118 )
  23. GRB 240414A: Fermi GBM Observation
  24. Fermi GRB 240415A: Global MASTER-Net observations report
  25. GRB 240415A: Mondy optical transient detection
  26. GRB 240414A: Photometric observation from 2.2m CAHA
  27. GRB 240414A: Swift/UVOT Detection
  28. LXT 240402A/GRB 240402B: Swift follow-up observations
  29. GRB 240414A: Mondy optical observations
  30. GRB 240414B: Fermi GBM Final Real-time Localization
  31. GRB 240414A: AKO Optical Upper Limit
  32. GRB 240415A: Prompt Swift-XRT observations
  33. GRB 240415A: Swift detection of a burst
  34. GRB 240415A: Fermi GBM Final Real-time Localization
  35. EP240413a: Upper limits from GECAM-B Observation
  36. GRB 240414A: Swift-XRT refined Analysis
  37. GRB240414A : J-band upper limits from WINTER
  38. GRB 240414A: Enhanced Swift-XRT position
  39. GRB 240414A : OHP/T193 second epoch of optical follow-up and afterglow detection
  40. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  41. GRB 240414A: Skynet Optical Afterglow Observations
  42. Fermi trigger No 734754044: Global MASTER-Net observations report
  43. Swift GRB 240414A: Global MASTER-Net observations report
  44. IPN triangulation of GRB 240410A
  45. IPN triangulation of GRB 240411A
  46. Fermi-LAT gamma-ray observations of IceCube-240412A
  47. GRB 240414A : MITSuME Akeno optical upper limits
  48. GRB 240414A: Redshift confirmation from GTC/OSIRIS+
  49. GRB 240414A : OHP/T193 redshift determination
  50. GRB 240414A : OHP/T193 optical counterpart detection
  51. GRB 240414A: Swift detection of a burst
  52. GRB 240411B: CrAO/ZTSh optical observations
  53. GRB 240411B: Kinder observations with Lulin observatory
  54. GRB 240411B: HiPERCAM/GTC observation
  55. GRB 240411B: Swift-BAT refined analysis
  56. GRB 240411B: Swift-XRT refined Analysis
  57. IceCube-240412A - IceCube observation of a high-energy neutrino candidate track-like event
  58. GRB 240411B: 1.3m DFOT Optical observations
  59. GRB 240411A: GRBAlpha detection
  60. GRB 240411B: OHP/T193 optical observations
  61. GRB 240405A: Glowbug gamma-ray detection
  62. GRB 240411B: Enhanced Swift-XRT position
  63. GRB 240411B: LCO optical afterglow detection
  64. GRB 240411B: Swift detection of a burst
  65. GRB 240408B: GRBAlpha detection
  66. GRB 240411A: Fermi GBM Final Real-time Localization
  67. EP240408a: Upper limits from GECAM-B Observation
  68. GRB 240405A: GRBAlpha detection
  69. GRB 240408B: AstroSat CZTI detection
  70. Fermi GRB 240408A: Global MASTER-Net observations report
  71. GRB 240408A: Fermi GBM Final Real-time Localization
  72. GRB 240407A: BALROG localization (Fermi Trigger 734144396 / GRB 240407042)
  73. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  74. Fermi GRB 240407A: Global MASTER-Net observations report
  75. GRB 240407A: Fermi GBM Final Real-time Localization
  76. Fermi-LAT gamma-ray observations of IceCube-240327B
  77. Fermi-LAT gamma-ray observations of IceCube-240327A
  78. LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation
  79. Fermi GRB 240405B: Global MASTER-Net observations report
  80. GRB 240405B: Fermi GBM Final Real-time Localization
  81. GRB 240402C: Glowbug gamma-ray detection
  82. GRB 240405A: Fermi GBM Final Real-time Localization
  83. GRB 240402C: GRBAlpha detection
  84. GRB 240331A: GRBAlpha detection
  85. LXT 240402A/GRB 240402B: GECAM-C refined analysis
  86. GRB 240403B: Glowbug gamma-ray detection
  87. GRB 240403A: Glowbug gamma-ray detection
  88. LXT 240402A/GRB 240402B: Glowbug gamma-ray detection
  89. Konus-Wind detection of LXT 240402A/GRB 240402B
  90. GRB/FXT 240402B: Kinder optical counterpart candidate
  91. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  92. GRB 240403A: Fermi GBM Detection
  93. LXT 240402A: EP-FXT detection of the X-ray afterglow
  94. Fermi GRB 240404A: Global MASTER-Net observations report
  95. GRB 240404A: Fermi GBM Final Real-time Localization
  96. GRB 240402B: GWAC-F50A optical upper limit
  97. GRB 240402B: GECAM-C detection
  98. GRB 240403A: BALROG localization (Fermi Trigger 733838255 / GRB 240403498)
  99. Fermi trigger No 733808041: Global MASTER-Net observations report
  100. Fermi GRB 240402A: Global MASTER-Net observations report

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