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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"

41997 results found.

  1. GRB 160925A: Kottamia R-band observation
  2. Konus-Wind observation of GRB 161004B
  3. GRB 160927A: GTC observations
  4. GRB 161004B: CALET Gamma-Ray Burst Monitor detection
  5. GRB 160927A: CALET Gamma-Ray Burst Monitor ground detection
  6. GRB 161004A: Swift-BAT refined analysis
  7. GRB 150302A: late-time imaging and optical afterglow confirmation
  8. GRB 161001A: IRSF upper limits
  9. GRB 161004B: Fermi GBM detection
  10. GRB 161004B: Swift/UVOT Upper Limits
  11. GRB161004B: AstroSat CZTI detection
  12. GRB 161004B: Swift-BAT refined analysis
  13. GRB 161004B: Swift-XRT refined Analysis
  14. GRB 161004A: RATIR Optical and NIR Observations
  15. GRB 160917A: Lomonosov BDRG gamma ray detection
  16. GRB 161004B: Swift detection of a burst
  17. GRB 161004A: SAO RAS optical upper limit
  18. GRB 161004A: Swift-XRT refined Analysis
  19. GRB 161004A: Swift/UVOT Detection
  20. Swift Trigger 715209 is not an astrophysical event
  21. GRB 161004A: Bassano Bresciano Observatory upper limit
  22. GRB 161004A: TSHAO optical observations
  23. GRB 161004A: Swift detection of a burst with a possible optical counterpart
  24. GRB 160927A: 15 GHz upper limits from AMI
  25. Konus-Wind observation of GRB 161001A (short/hard ?)
  26. GRB 161001A: MASTER-OAFA and MASTER-SAAO early optical observations
  27. GRB 161001A: GROND afterglow candidate
  28. GRB 161001A, Swift-BAT refined analysis (likely a short GRB)
  29. GRB 161001A: Fermi GBM detection
  30. GRB 161001A: Swift-XRT refined Analysis
  31. GRB 161001A: X-shooter spectroscopy, candidate host galaxy and redshift
  32. GRB 161001A: Swift/UVOT Upper Limits
  33. GRB 161001A: Swift detection of a burst
  34. Possible radio detection of GRB 160910A with the GMRT
  35. Fermi GBM trigger 496791348/160928900 is not a GRB
  36. GRB 160927A: Magellan imaging
  37. GRB 160927A: Swift/UVOT Upper Limits
  38. GRB 160927A: Bassano Bresciano Observatory optical upper limit
  39. GRB 160927A: Swift-BAT refined analysis
  40. GRB 160927A: NOT optical observations
  41. GRB 160927A: GROND Observations
  42. GRB 160927A: Swift-XRT refined Analysis
  43. GRB 160927A: TNG optical afterglow confirmation
  44. GRB160927A: D50 optical limit
  45. GRB 160927A: RTT150 optical afterglow candidate
  46. GRB 160927A: Swift detection of a short hard burst
  47. GRB 160917A: 15 GHz upper limits from AMI
  48. GRB 160912A: 15 GHz upper limits from AMI
  49. GRB160910A: AstroSat CZTI detection
  50. XRT refined analysis for GRB 160925A
  51. GRB 160925A/MASTER optical transient: Mondy optical observations
  52. GRB 160925A: MITSuME Akeno Optical Observations
  53. GRB 160925A: Bassano Bresciano Photometry of MASTER optical transient
  54. GRB 160925A: Optical spectroscopy of MASTER optical transient
  55. GRB160824B: AstroSat CZTI detection
  56. GRB160917A: AstroSat CZTI detection
  57. GRB 160925A / Fermi 496473540: MASTER OT observations
  58. GRB 160925A: Swift ToO observations
  59. GRB160925A / Fermi 496473540: MASTER optical transient confirmation by LCOGT-FTN
  60. GRB 160925A / Fermi 496473540: Global MASTER Net OT discovery
  61. GRB 160910A: 15 GHz detection from AMI
  62. GRB 160917A: Mondy afterglow confirmation
  63. GRB 160910A: TSHAO optical observations
  64. GRB 160917A: Swift-BAT refined analysis
  65. GRB 160917A: RATIR Optical and NIR Observations
  66. GRB 160917A: Fermi GBM observation
  67. GRB 160917A: Swift/UVOT Detection
  68. GRB 160917A: Swift-XRT refined Analysis
  69. GRB 160917A: Mondy optical observations
  70. GRB 160917A: OSN I-band upper limits
  71. GRB 160917A: Swift detection of a burst
  72. GRB 160910A: Maidanak optical observations
  73. GRB 160912A, Swift-BAT refined analysis
  74. GRB 160910A: Swift/UVOT Detection
  75. GRB 160912A: RATIR Optical and NIR Observations
  76. GRB 160912A: Swift/UVOT Weak Afterglow Detection
  77. GRB 160912A: Mondy optical observations
  78. GRB 160910A: Mondy optical observations
  79. GRB 160912A Liverpool Telescope optical afterglow
  80. GRB 160912A: Swift-XRT refined Analysis
  81. GRB 160912A: Fermi GBM detection
  82. GRB 160910A: Global MASTER Net OT detection before LAT alert
  83. Konus-Wind observation of GRB 160910A
  84. GRB 160912A: Swift detection of a burst
  85. GRB 160910A: Correction to GCN 19904
  86. GRB 160910A: XRT results and corrections to GCN 19905 & 19906
  87. GRB 160910A: CALET Gamma-Ray Burst Monitor detection
  88. GRB 160910A: NOT afterglow confirmation
  89. GRB 160910A: Afterglow detection from OSN
  90. GRB 160910A: Tiled Swift observations
  91. GRB 160910A: Swift-XRT afterglow detection
  92. GRB 160908A: CALET Gamma-Ray Burst Monitor detection
  93. GRB 160910A: Fermi-LAT detection
  94. GRB 160910A: Fermi GBM observation
  95. Konus-Wind observation of GRB 160905A
  96. GRB 160824A: 15 GHz upper limits from AMI
  97. GRB 160821B: 15 GHz upper limits from AMI
  98. GRB 160905A: Swift/UVOT Detection
  99. GRB 160905A: Swift-BAT refined analysis
  100. Swift Trigger 711158 is not an astrophysical event

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