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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"

36322 results found.

  1. GRB230420A: VLT optical observation
  2. GRB 230420A: Swift-BAT refined analysis
  3. GRB 230421A: Fermi GBM Final Real-time Localization
  4. GRB 230420A: Swift-XRT refined Analysis
  5. GRB 230420A: MITSuME Akeno optical observation
  6. GRB 230420A: NOT optical afterglow confirmation
  7. GRB 230420A: Gaoyazi/GOT optical upper limit
  8. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  9. GRB 230420A: LCOGT Optical Upper Limit
  10. GRB 230420A: Enhanced Swift-XRT position
  11. IPN triangulation of GRB 230418A (short)
  12. GRB 230420A: Swift detection of a burst
  13. GRB 230418A: AstroSat CZTI detection
  14. GRB 230418A: AGILE detection
  15. GRB 230402A: Fermi GBM detection
  16. GRB 230419A: Fermi GBM Final Real-time Localization
  17. GRB 230418A: Swift/BAT-GUANO detection outside the coded FOV
  18. GRB 230418A: Fermi GBM Observation
  19. GRB 230402A: Fermi-LAT detection
  20. GRB 230414B: Nickel and KAIT telescope optical observations
  21. GRB 230414B Swift-BAT refined analysis
  22. GRB 230415A: Fermi GBM detection
  23. GRB 230414B: Swift/UVOT Detection
  24. GRB 230414B: Osservatorio Astronomico Nastro Verde - Sorrento: optical observations
  25. GRB 230415A: Swift/BAT-GUANO detection
  26. New GCN Circulars Portal for Rapid Communications on Astronomical Transients is Online
  27. GRB 230414B: 3.6m DOT Optical observations, slow decay at early epochs
  28. GRB 230307A: iTelescope optical upper limit (likely)
  29. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  30. GRB 230414B: Lulin 40cm-SLT optical limit
  31. GRB 230414B: Bassano Bresciano Observatory optical observations
  32. GRB 230414B: Redshift from OSIRIS/GTC
  33. GRB 230414B: AbAO optical observations
  34. GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
  35. GRB 230414B: Swift-XRT refined Analysis
  36. GRB 230414B: Dabancheng/GHOST optical observations
  37. GRB 230414B: slow optical light curve decay
  38. GRB 230414B: SAO RAS optical observations
  39. GRB 230414B: Enhanced Swift-XRT position
  40. GRB 230414B: 1.3m DFOT Optical observations
  41. Fermi GRB 230414A: Global MASTER-Net observations report
  42. GRB 230414B: GROWTH India Telescope afterglow confirmation
  43. GRB 230414B (correction GRB name in the GCN 33615): Mondy optical afterglow candidate
  44. GRB 230414B: Nanshan/HMT optical afterglow detection
  45. GRB 230414A: Mondy optical afterglow candidate
  46. Swift GRB 230414B: Global MASTER-Net observations report
  47. GRB 230414B: Prompt enhanced Swift-XRT position
  48. GRB 230414B: Swift detection of a burst
  49. GRB 230414A: Fermi GBM Final Real-time Localization
  50. GRB 230328B: redshift lower limit estimating
  51. GRB 230409B: Mondy optical upper limit
  52. GRB 230409B: OHP/T193 optical upper limit
  53. GRB 230410B: VZLUSAT-2 detection
  54. GRB 230409D: VZLUSAT-2 detection
  55. GRB 230410B: AGILE detection of a burst
  56. GRB 230410A: Fermi GBM Final Real-time Localization
  57. Fermi GRB 230409C: Global MASTER-Net observations report
  58. Fermi GRB 230409A: Global MASTER-Net observations report
  59. GRB 230409C: Fermi GBM Final Real-time Localization
  60. GRB 230409B: Swift-XRT refined Analysis
  61. GRB 230409B: Swift-BAT refined analysis
  62. Swift GRB 230409B: Global MASTER-Net observations report
  63. GRB 230409B: Swift/UVOT Detection
  64. GRB 230409B: Enhanced Swift-XRT position
  65. GRB 230409B: Swift detection of a burst
  66. GRB 230409A: Fermi GBM Final Real-time Localization
  67. GRB 230405B: VZLUSAT-2 detection
  68. Konus-Wind detection of GRB 230405B
  69. GRB 230405B: AGILE detection
  70. GRB 230405B: Swift-XRT refined Analysis
  71. GRB 230405B: Fermi GBM Observation
  72. GRB 230405B: MeerLICHT upper limits
  73. GRB 230307A: JWST NIRSpec observations, possible higher redshift
  74. GRB 230307A: further analysis of the Konus-Wind detection and rest-frame energetics
  75. GRB 230307A: good match with kilonova models
  76. GRB 230307A: short mininum variability timescale compatible with a merger origin
  77. GRB 230405B: Swift/UVOT Upper Limits
  78. GRB 230405B: AstroSat CZTI detection
  79. GRB 230405B: Enhanced Swift-XRT position
  80. Swift GRB 230405B: Global MASTER-Net observations report
  81. GRB 230405B: Prompt enhanced Swift-XRT position
  82. GRB 230405B: Swift detection of a burst
  83. GRB 230405B: Fermi GBM Final Real-time Localization
  84. GRB 230307A: JWST observations consistent with the presence of a kilonova
  85. Fermi GRB 230405A: Global MASTER-Net observations report
  86. GRB 230405A: Fermi GBM Final Real-time Localization
  87. GRB 230404A: AstroSat CZTI detection
  88. GRB 230404A: Fermi GBM Final Real-time Localization
  89. GRB 230402A: CALET Gamma-Ray Burst Monitor detection
  90. GRB 230402A: AstroSat CZTI detection
  91. GRB 230328B: Multa observatory optical afterglow observation
  92. GRB 230307A: Chandra late-time detection of the X-ray afterglow
  93. GRB 230228A: detection by GTC of the potential host galaxy
  94. GRB 230328B: Swift/UVOT Detection
  95. GRB 230402A: AGILE detection
  96. Fermi GRB 230402A: Global MASTER-Net observations report
  97. GRB 230402A: Fermi GBM Final Real-time Localization
  98. GRB 230307A: Bad Time Intervals for Fermi GBM data
  99. GRB 230328B : GRANDMA/Kilonova-Catcher optical detection
  100. GRB 230328B: CAHA 2.2m/CAFOS detection

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