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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"
  1. GRB 160927A: Magellan imaging
  2. GRB 160927A: Swift/UVOT Upper Limits
  3. GRB 160927A: Bassano Bresciano Observatory optical upper limit
  4. GRB 160927A: Swift-BAT refined analysis
  5. GRB 160927A: NOT optical observations
  6. GRB 160927A: GROND Observations
  7. GRB 160927A: Swift-XRT refined Analysis
  8. GRB 160927A: Enhanced Swift-XRT position
  9. GRB 160927A: TNG optical afterglow confirmation
  10. GRB160927A: D50 optical limit
  11. GRB 160927A: RTT150 optical afterglow candidate
  12. GRB 160927A: Prompt enhanced Swift-XRT position
  13. GRB 160927A: Swift detection of a short hard burst
  14. GRB 160917A: 15 GHz upper limits from AMI
  15. GRB 160912A: 15 GHz upper limits from AMI
  16. GRB160910A: AstroSat CZTI detection
  17. XRT refined analysis for GRB 160925A
  18. GRB 160925A/MASTER optical transient: Mondy optical observations
  19. GRB 160925A: MITSuME Akeno Optical Observations
  20. GRB 160925A: Bassano Bresciano Photometry of MASTER optical transient
  21. GRB 160925A: Optical spectroscopy of MASTER optical transient
  22. GRB160824B: AstroSat CZTI detection
  23. GRB160917A: AstroSat CZTI detection
  24. GRB 160925A / Fermi 496473540: MASTER OT observations
  25. GRB 160925A: Swift ToO observations
  26. GRB160925A / Fermi 496473540: MASTER optical transient confirmation by LCOGT-FTN
  27. GRB 160925A / Fermi 496473540: Global MASTER Net OT discovery
  28. GRB 160910A: 15 GHz detection from AMI
  29. GRB 160917A: Mondy afterglow confirmation
  30. GRB 160910A: TSHAO optical observations
  31. GRB 160917A: Swift-BAT refined analysis
  32. GRB 160917A: RATIR Optical and NIR Observations
  33. GRB 160917A: Fermi GBM observation
  34. GRB 160917A: Swift/UVOT Detection
  35. GRB 160917A: Swift-XRT refined Analysis
  36. GRB 160917A: Mondy optical observations
  37. GRB 160917A: OSN I-band upper limits
  38. GRB 160917A: Enhanced Swift-XRT position
  39. GRB 160917A: Swift detection of a burst
  40. GRB 160910A: Maidanak optical observations
  41. GRB 160912A, Swift-BAT refined analysis
  42. GRB 160910A: Swift/UVOT Detection
  43. GRB 160912A: RATIR Optical and NIR Observations
  44. GRB 160912A: Swift/UVOT Weak Afterglow Detection
  45. GRB 160912A: Mondy optical observations
  46. GRB 160910A: Mondy optical observations
  47. GRB 160912A Liverpool Telescope optical afterglow
  48. GRB 160912A: Swift-XRT refined Analysis
  49. GRB 160912A: Fermi GBM detection
  50. GRB 160912A: Enhanced Swift-XRT position
  51. GRB 160910A: Global MASTER Net OT detection before LAT alert
  52. Konus-Wind observation of GRB 160910A
  53. GRB 160912A: Swift detection of a burst
  54. GRB 160910A: Correction to GCN 19904
  55. GRB 160910A: XRT results and corrections to GCN 19905 & 19906
  56. GRB 160910A: CALET Gamma-Ray Burst Monitor detection
  57. GRB 160910A: NOT afterglow confirmation
  58. GRB 160910A: Afterglow detection from OSN
  59. GRB 160910A: Tiled Swift observations
  60. GRB 160910A: Swift-XRT afterglow detection
  61. GRB 160908A: CALET Gamma-Ray Burst Monitor detection
  62. GRB 160910A: Fermi-LAT detection
  63. GRB 160910A: Fermi GBM observation
  64. Konus-Wind observation of GRB 160905A
  65. GRB 160824A: 15 GHz upper limits from AMI
  66. GRB 160821B: 15 GHz upper limits from AMI
  67. GRB 160905A: Swift/UVOT Detection
  68. GRB 160905A: Swift-BAT refined analysis
  69. Swift Trigger 711158 is not an astrophysical event
  70. GRB 160905A: Swift-XRT refined Analysis
  71. GRB 160821A: 15 GHz upper limits from AMI
  72. GRB 160816A: Possible radio afterglow detection at 15 GHz with AMI
  73. GRB 160905A: Enhanced Swift-XRT position
  74. GRB 160905A: Fermi-LAT detection
  75. GRB 160905A: Fermi GBM observation
  76. IceCube HESE 160814: MASTER OT J130845.02-323254.9 as the possible source of the high energy neutrino
  77. GRB 160905A: Swift detection of a burst with an optical counterpart
  78. Fermi GBM trigger 494508549 / 160902479 is not a GRB
  79. Search for counterpart to IceCube-160814A with ANTARES
  80. GRB 160824B: Lomonosov BDRG gamma ray detection and MASTER limit
  81. GRB 160829A: Swift-XRT observations
  82. GRB 160829A: Fermi GBM Detection
  83. GRB 160816A, the review of the sky area in plate archives
  84. GRB 160829A: Swift ToO observations
  85. GRB 160829A: Fermi-LAT detection of a short GRB
  86. GRB 160827A: Swift-BAT refined analysis
  87. Swift trigger 710022 is not astrophysical
  88. GRB 160827A: Swift detection of a burst
  89. Correction to Circular 19874 (on Swift trigger 71022)
  90. Swift Trigger 710022 is very likely noise
  91. GRB 160824B: CALET Gamma-Ray Burst Monitor detection
  92. GRB 160826A: Swift-BAT refined analysis
  93. GRB 160826A: Swift/UVOT Upper Limits
  94. GRB 160825A: not localized by Swift
  95. GRB 160820A: Fermi GBM observation
  96. GRB 160826A: Swift-XRT refined Analysis
  97. GRB160821A: Astrosat CZTI (veto) detection
  98. GRB 160826A: Swift detection of a burst
  99. GRB 160821A: CALET Gamma-Ray Burst Monitor detection
  100. GRB 160825A: Swift ToO observations

Advanced

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