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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"

39290 results found.

  1. GRB 240414A: Glowbug gamma-ray detection
  2. GRB 240415B: GECAM-B detection
  3. EP 240416a: Xinglong and NOT decaying optical counterpart
  4. GRB 240415A: Swift-BAT refined analysis
  5. EP240416A: MASTER optical observations
  6. GRB 240411A: Glowbug gamma-ray detection
  7. GRB 240414A: Swift-BAT refined analysis
  8. GRB 240414A: AbAO optical upprer limit
  9. GRB 240415A: Swift/UVOT Detection
  10. GRB 240415A: Fermi GBM Observation
  11. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  12. GRB 240415A: Earliest optical followup with the Kinder observations
  13. GRB 240414A: GMG observation
  14. EP 240414a: BOOTES-4/MET Optical Upper Limits
  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. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  53. EP240408a: GSP optical upper limit
  54. GRB 240411B: CrAO/ZTSh optical observations
  55. GRB 240411B: Kinder observations with Lulin observatory
  56. LIGO/Virgo/Kagra S240413p: NED Galaxies in the Localization Volume
  57. GRB 240411B: HiPERCAM/GTC observation
  58. IceCube Alert 240412.23: Global MASTER-Net observations report
  59. GRB 240411B: Swift-BAT refined analysis
  60. GRB 240411B: Swift-XRT refined Analysis
  61. GRB 240411B: 1.3m DFOT Optical observations
  62. GRB 240411A: GRBAlpha detection
  63. GRB 240411B: OHP/T193 optical observations
  64. GRB 240405A: Glowbug gamma-ray detection
  65. GRB 240411B: Enhanced Swift-XRT position
  66. GRB 240411B: LCO optical afterglow detection
  67. GRB 240411B: Swift detection of a burst
  68. GRB 240408B: GRBAlpha detection
  69. GRB 240411A: Fermi GBM Final Real-time Localization
  70. EP240408A: MASTER optical observations
  71. EP240408a: GROND detection of a candidate counterpart
  72. EP240408a: Upper limits from GECAM-B Observation
  73. GRB 240405A: GRBAlpha detection
  74. Swift Trigger 1220736: detection of 4U 1543-62.
  75. GRB 240408B: AstroSat CZTI detection
  76. Fermi GRB 240408A: Global MASTER-Net observations report
  77. GRB 240408A: Fermi GBM Final Real-time Localization
  78. GRB 240407A: BALROG localization (Fermi Trigger 734144396 / GRB 240407042)
  79. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  80. Fermi GRB 240407A: Global MASTER-Net observations report
  81. GRB 240407A: Fermi GBM Final Real-time Localization
  82. Fermi-LAT gamma-ray observations of IceCube-240327B
  83. Fermi-LAT gamma-ray observations of IceCube-240327A
  84. LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation
  85. Fermi GRB 240405B: Global MASTER-Net observations report
  86. GRB 240405B: Fermi GBM Final Real-time Localization
  87. GRB 240402C: Glowbug gamma-ray detection
  88. GRB 240405A: Fermi GBM Final Real-time Localization
  89. GRB 240402C: GRBAlpha detection
  90. GRB 240331A: GRBAlpha detection
  91. LXT 240402A/GRB 240402B: GECAM-C refined analysis
  92. GRB 240403B: Glowbug gamma-ray detection
  93. GRB 240403A: Glowbug gamma-ray detection
  94. LXT 240402A/GRB 240402B: Glowbug gamma-ray detection
  95. Konus-Wind detection of LXT 240402A/GRB 240402B
  96. GRB/FXT 240402B: Kinder optical counterpart candidate
  97. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  98. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  99. GRB 240403A: Fermi GBM Detection
  100. LXT 240402A: EP-FXT detection of the X-ray afterglow

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