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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"

36398 results found.

  1. GRB 230506B: Fermi GBM detection
  2. GRB 230510A: Swift-XRT refined Analysis
  3. GRB 230510A: Enhanced Swift-XRT position
  4. GRB 230506C: Fermi GBM detection
  5. Fermi Gamma-ray Burst Monitor trigger 230510133/705381054 is not a GRB
  6. GRB 230510A: Swift detection of a burst
  7. GRB 230510A: Fermi GBM Final Real-time Localization
  8. GRB 230506B: Swift/UVOT further analysis
  9. GRB 230506C: T193-OHP MISTRAL tentative redshift
  10. GRB 230506C: SAO RAS optical observations
  11. GRB 230307A: JWST second-epoch observations
  12. IceCube-230506A: Upper limits from a search for additional neutrino events in IceCube
  13. GRB 230506C: Swift-XRT refined Analysis
  14. GRB 230506C: Swift-BAT refined analysis
  15. GRB 230506B: Swift-BAT refined analysis
  16. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  17. GRB 230506B: LCOGT Optical Upper Limits
  18. GRB 230506C: Swift/UVOT Upper Limits
  19. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  20. GRB 230506B: Swift-XRT refined Analysis
  21. GRB 230506C: Swift-XRT analysis
  22. GRB 230506C: Candidate afterglow observation by D50
  23. GRB 230506C: TSHAO possible afterglow candidate
  24. GRB 230506B: Swift/UVOT Detection
  25. GRB 230506C: Swift detection of a burst
  26. GRB 230506B: Swift detection of a burst
  27. GRB 230506B: MASTER optical observations
  28. GRB 230506B: Swift detection of a burst
  29. GRB 230506A: Fermi GBM Final Real-time Localization
  30. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  31. GRB 230430A: A short GRB from a neutron star merger
  32. GRB 230427A: Swift-BAT refined analysis
  33. GRB 230503A: Fermi GBM Final Real-time Localization
  34. Konus-Wind detection of GRB 230430A
  35. IPN triangulation of GRB 230430A (short)
  36. GRB 230420A: AROMA-N Optical Upper Limit
  37. GRB 230430B: Fermi GBM Final Localization
  38. GRB 230430A: Fermi GBM observation
  39. GRB 230430A: AstroSat CZTI detection
  40. GRB 230430A: Fermi GBM Final Real-time Localization
  41. GRB 230427A: NOT optical upper limit
  42. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  43. GRB 230427A: Swift/UVOT Detection
  44. GRB 230427A: Gaoyazi/GOT optical upper limit
  45. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7
  46. GRB 230427A: Nanshan/HMT optical upper limit
  47. GRB 230427A: Osservatorio Astronomico Nastro verde upper limit
  48. GRB 230427A: OSIRIS+/GTC observations
  49. GRB 230427A: Swift-XRT refined Analysis
  50. GRB 230426A: VZLUSAT-2 detection
  51. GRB 230428A: Fermi GBM Final Real-time Localization
  52. GRB 230427A: GIT optical upper limit
  53. GRB 230427A: Bassano Bresciano Observatory upper limit
  54. GRB 230427A: GMG upper limit
  55. GRB 230427A : OHP/T193 optical upper limit
  56. GRB 230427A: BOOTES-5/JGT afterglow detection
  57. GRB 230423A(trigger #1165354): Swift-BAT refined analysis
  58. GRB 230427A: AKO Upper Limit
  59. GRB 230426A: MASTER OT J023135.16-792104.8 optical counterpart discovery
  60. GRB 230427A: MITSuME Akeno optical upper limits
  61. GRB 230426A: Fermi GBM Detection
  62. GRB 230427A: Enhanced Swift-XRT position
  63. GRB 230427A: Swift detection of a burst with an optical counterpart
  64. GRB 230426A: AstroSat CZTI detection
  65. GRB 230426A: Fermi GBM Final Real-time Localization
  66. GRB 230423A: Swift/UVOT Upper Limits
  67. GRB 230425A: Fermi GBM Final Real-time Localization
  68. GRB 230423A: Swift-XRT refined Analysis
  69. GRB 230420A: Lowell Discovery Telescope Optical Detection
  70. GRB 230423A: Swift-XRT afterglow detection
  71. Swift Trigger 1165354 is probably not a GRB
  72. GRB 221009A: Late-time JWST Observations and Detection of Supernova Emission
  73. GRB 230421A: Fermi GBM observation
  74. Konus-Wind detection of GRB 230418A
  75. GRB 230420A: Swift/UVOT Upper Limits
  76. GRB 230421: Swift/BAT-GUANO arcminute localization
  77. GRB230420A: VLT optical observation
  78. GRB 230420A: Swift-BAT refined analysis
  79. GRB 230421A: Fermi GBM Final Real-time Localization
  80. GRB 230420A: Swift-XRT refined Analysis
  81. GRB 230420A: MITSuME Akeno optical observation
  82. GRB 230420A: NOT optical afterglow confirmation
  83. GRB 230420A: Gaoyazi/GOT optical upper limit
  84. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  85. GRB 230420A: LCOGT Optical Upper Limit
  86. GRB 230420A: Enhanced Swift-XRT position
  87. IPN triangulation of GRB 230418A (short)
  88. GRB 230420A: Swift detection of a burst
  89. GRB 230418A: AstroSat CZTI detection
  90. GRB 230418A: AGILE detection
  91. GRB 230402A: Fermi GBM detection
  92. GRB 230419A: Fermi GBM Final Real-time Localization
  93. GRB 230418A: Swift/BAT-GUANO detection outside the coded FOV
  94. GRB 230418A: Fermi GBM Observation
  95. GRB 230402A: Fermi-LAT detection
  96. GRB 230414B: Nickel and KAIT telescope optical observations
  97. GRB 230414B Swift-BAT refined analysis
  98. GRB 230415A: Fermi GBM detection
  99. GRB 230414B: Swift/UVOT Detection
  100. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations

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