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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 160824A: 1.5m OSN I-band observation
  2. GRB 160824A: ISON/Terskol optical observations
  3. GRB 160824A: Swift-BAT refined analysis
  4. GRB 160824A: Swift/UVOT Possible Afterglow Detection
  5. GRB 160824A: Bassano Bresciano Observatory upper limits
  6. GRB 160824A: Swift-XRT refined Analysis
  7. GRB 160824A: Enhanced Swift-XRT position
  8. GRB 160824B: Fermi GBM detection
  9. GRB 160824A: Swift detection of a burst
  10. GRB 160821B: VLA 5.0 GHz observations
  11. Konus-Wind observation of GRB 160822A
  12. IPN Triangulation of GRB 160822A (short/hard)
  13. Konus-Wind observation of GRB 160820A
  14. IPN Triangulation of GRB 160820A (short/hard)
  15. Possible radio detection of GRB160703A with the GMRT
  16. Possible radio detection of GRB160623A with the GMRT
  17. GRB 160821B: GTC follow-up observation
  18. GRB 160821B: WHT afterglow confirmation and redshift of candidate host
  19. GRB 160822672: Fermi GBM detection
  20. GRB 160821B: Swift-BAT refined analysis
  21. GRB 160821B: Fermi GBM Detection
  22. Konus-Wind observation of GRB 160821A
  23. GRB 160821B: Swift-XRT refined Analysis
  24. GRB 160821A: Swift-BAT refined analysis
  25. GRB 160821B: Swift/UVOT Upper Limits
  26. Short GRB 160821B: MASTER early optical observations
  27. GRB 160821B: Enhanced Swift-XRT position
  28. GRB 160821A: Fermi-LAT refined analysis
  29. GRB 160821A: Fermi GBM Detection
  30. GRB 160821B: NOT optical afterglow candidate
  31. GRB 160821B: Swift detection of a short burst
  32. GRB 160821A: TAROT Calern observatory optical detection
  33. GRB 160821A: Fermi-LAT detection of a bright burst
  34. GRB 160821A: Swift detection of a bright burst
  35. GRB 160816A: TSHAO optical observations
  36. INTEGRAL/SPI-ACS observation of IceCube HESE 128340 58537957
  37. BAT detection and localization of GRB 160819A
  38. GRB 160819A: Fermi GBM detection
  39. GRB 160816A: ISON/UAFO optical observations
  40. GRB 160816A: Further RATIR Optical and NIR Observations
  41. GRB 160815A: CALET Gamma-Ray Burst Monitor detection
  42. IBAS Alert 7534: Not a real GRB
  43. GRB 160816A: MASTER OT early detection on coaded images
  44. GRB 160816A: RATIR Optical and NIR Afterglow Confirmation
  45. GRB 160816A: confirmed fading with the LT
  46. GRB 160816A iTelescope observation
  47. Fermi GBM Observations of IceCube-160806A
  48. GRB 160814A: CALET Gamma-Ray Burst Monitor detection
  49. GRB 160816A: Swift/UVOT Detection
  50. GRB 160816A: IPN annulus
  51. GRB 160804A: 15 GHz detections and upper limit from AMI
  52. GRB 160801A: 15 GHz upper limits from AMI
  53. GRB 160714A: 15 GHz upper limits from AMI
  54. Konus-Wind observation of GRB 160816A
  55. GRB 160816A: RATIR Optical and NIR Observations
  56. GRB 160816A: LCOGT-FTN optical candidate
  57. GRB 160815A: GWAC-F60A upper limit
  58. GRB 160816A: Swift-XRT afterglow detection
  59. GRB 160816A: MASTER inspection
  60. GRB 160816730A: Fermi GBM detection/observation
  61. GRB 160816A: Swift ToO observations
  62. GRB 160816A: Fermi-LAT detection
  63. GRB 160815A: Swift/UVOT Detection
  64. Konus-Wind observation of GRB 160814A
  65. GRB 160815A: Swift-BAT refined analysis
  66. GRB 160815A: Swift-XRT refined Analysis
  67. GRB 160815A: Fermi GBM detection/observation
  68. GRB 160815A: Enhanced Swift-XRT position
  69. GRB 160815A: Swift/UVOT Afterglow Detection
  70. GRB 160815A: Swift detection of a burst
  71. GRB 160814A: MAXI/GSC detection
  72. GRB 160804B: CALET Gamma-Ray Burst Monitor detection
  73. IceCube 160806A: Lomonosov BDRG gamma ray prompt observations
  74. Fermi GBM trigger 160812507/492696620 is not a GRB
  75. INTEGRAL/SPI-ACS and IBIS_VETO search for prompt gamma-ray counterpart of IceCube-160806A
  76. Fermi GBM trigger 160810523/492525192 is not a GRB
  77. IceCube 160806A EHE Neutrino Candidate Event
  78. GRB 160806A: Fermi GBM observation
  79. Konus-Wind observation of GRB 160806A
  80. IPN Triangulation of GRB 160806A
  81. Swift Trigger 707517 is not an astrophysical event
  82. GRB160802A - Astrosat CZTI detection
  83. Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
  84. Swift Trigger 707517 is probably not a GRB
  85. GRB 160804A: RATIR Optical and NIR Observations
  86. GRB 160802A: CALET Gamma-Ray Burst Monitor detection
  87. IceCube-160731A: Konus-Wind limits
  88. GRB 160804A: TSHAO optical observations
  89. GRB 160804A: ISON/UAFO optical observations
  90. GRB 160804A: GROND observations
  91. GRB 160804A: VLT/X-shooter redshift
  92. Search for counterpart to IceCube-160731A with ANTARES
  93. GRB 160804A: SAO RAS optical observations
  94. GRB 160804A: TNG optical observations, afterglow fading and candidate host galaxy
  95. GRB 160804A: Fermi GBM observation
  96. GRB160804A: MASTER-SAAO observation
  97. Konus-Wind observation of GRB 160802A
  98. IPN Triangulation of GRB 160802A
  99. GRB 160804A: Swift-BAT refined analysis
  100. GRB 160804A: Swift/UVOT Detection

Advanced

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