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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"

19697 results found.

  1. GRB 161004A: RATIR Optical and NIR Observations
  2. GRB 161004B: Enhanced Swift-XRT position
  3. GRB 161004B: Swift detection of a burst
  4. GRB 161004A: SAO RAS optical upper limit
  5. GRB 161004A: Swift/UVOT Detection
  6. GRB 161004A: Enhanced Swift-XRT position
  7. GRB 161004A: Bassano Bresciano Observatory upper limit
  8. GRB 161004A: TSHAO optical observations
  9. GRB 161004A: Swift detection of a burst with a possible optical counterpart
  10. GRB 161001A: MASTER-OAFA and MASTER-SAAO early optical observations
  11. GRB 161001A: GROND afterglow candidate
  12. GRB 161001A: X-shooter spectroscopy, candidate host galaxy and redshift
  13. GRB 161001A: Swift/UVOT Upper Limits
  14. GRB 161001A: Enhanced Swift-XRT position
  15. GRB 161001A: Swift detection of a burst
  16. GRB 160927A: Magellan imaging
  17. GRB 160927A: Swift/UVOT Upper Limits
  18. GRB 160927A: Bassano Bresciano Observatory optical upper limit
  19. GRB 160927A: NOT optical observations
  20. GRB 160927A: GROND Observations
  21. GRB 160927A: Enhanced Swift-XRT position
  22. GRB 160927A: TNG optical afterglow confirmation
  23. GRB 160927A: RTT150 optical afterglow candidate
  24. GRB 160927A: Swift detection of a short hard burst
  25. GRB160910A: AstroSat CZTI detection
  26. XRT refined analysis for GRB 160925A
  27. GRB 160925A/MASTER optical transient: Mondy optical observations
  28. GRB 160925A: MITSuME Akeno Optical Observations
  29. GRB 160925A: Swift ToO observations
  30. GRB 160917A: Mondy afterglow confirmation
  31. GRB 160910A: TSHAO optical observations
  32. GRB 160917A: RATIR Optical and NIR Observations
  33. GRB 160917A: Swift/UVOT Detection
  34. GRB 160917A: Mondy optical observations
  35. GRB 160917A: OSN I-band upper limits
  36. GRB 160917A: Enhanced Swift-XRT position
  37. GRB 160917A: Swift detection of a burst
  38. GRB 160910A: Swift/UVOT Detection
  39. GRB 160912A: RATIR Optical and NIR Observations
  40. GRB 160912A: Swift/UVOT Weak Afterglow Detection
  41. GRB 160912A: Mondy optical observations
  42. GRB 160910A: Mondy optical observations
  43. GRB 160912A Liverpool Telescope optical afterglow
  44. GRB 160912A: Enhanced Swift-XRT position
  45. GRB 160910A: Global MASTER Net OT detection before LAT alert
  46. GRB 160912A: Swift detection of a burst
  47. GRB 160910A: XRT results and corrections to GCN 19905 & 19906
  48. GRB 160910A: NOT afterglow confirmation
  49. GRB 160910A: Afterglow detection from OSN
  50. GRB 160910A: Tiled Swift observations
  51. GRB 160908A: CALET Gamma-Ray Burst Monitor detection
  52. GRB 160910A: Fermi-LAT detection
  53. GRB 160905A: Swift/UVOT Detection
  54. GRB 160905A: Enhanced Swift-XRT position
  55. GRB 160905A: Fermi-LAT detection
  56. IceCube HESE 160814: MASTER OT J130845.02-323254.9 as the possible source of the high energy neutrino
  57. GRB 160905A: Swift detection of a burst with an optical counterpart
  58. GRB 160829A: Swift ToO observations
  59. GRB 160827A: Swift detection of a burst
  60. Swift Trigger 710022 is very likely noise
  61. GRB 160826A: Swift/UVOT Upper Limits
  62. GRB 160825A: not localized by Swift
  63. GRB 160826A: Swift detection of a burst
  64. GRB 160825A: Swift ToO observations
  65. GRB 160824A: ISON/Terskol optical observations
  66. GRB 160824A: Swift/UVOT Possible Afterglow Detection
  67. GRB 160824A: Bassano Bresciano Observatory upper limits
  68. GRB 160824A: Swift-XRT refined Analysis
  69. GRB 160824A: Enhanced Swift-XRT position
  70. GRB 160824A: Swift detection of a burst
  71. IPN Triangulation of GRB 160822A (short/hard)
  72. IPN Triangulation of GRB 160820A (short/hard)
  73. GRB 160821B: GTC follow-up observation
  74. GRB 160822672: Fermi GBM detection
  75. GRB 160821B: Swift-BAT refined analysis
  76. GRB 160821B: Swift-XRT refined Analysis
  77. GRB 160821B: Swift/UVOT Upper Limits
  78. GRB 160821B: Enhanced Swift-XRT position
  79. GRB 160821B: NOT optical afterglow candidate
  80. GRB 160821B: Swift detection of a short burst
  81. GRB 160821A: TAROT Calern observatory optical detection
  82. GRB 160816A: TSHAO optical observations
  83. GRB 160816A: ISON/UAFO optical observations
  84. GRB 160816A: Further RATIR Optical and NIR Observations
  85. GRB 160816A: RATIR Optical and NIR Afterglow Confirmation
  86. GRB 160816A iTelescope observation
  87. Fermi GBM Observations of IceCube-160806A
  88. GRB 160816A: Swift/UVOT Detection
  89. GRB 160816A: RATIR Optical and NIR Observations
  90. GRB 160816A: Swift ToO observations
  91. GRB 160815A: Swift/UVOT Detection
  92. GRB 160815A: Swift-XRT refined Analysis
  93. GRB 160815A: Enhanced Swift-XRT position
  94. GRB 160815A: Swift detection of a burst
  95. INTEGRAL/SPI-ACS and IBIS_VETO search for prompt gamma-ray counterpart of IceCube-160806A
  96. Konus-Wind observation of GRB 160806A
  97. IPN Triangulation of GRB 160806A
  98. Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
  99. Swift Trigger 707517 is probably not a GRB
  100. GRB 160804A: RATIR Optical and NIR Observations

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