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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"

24763 results found.

  1. GRB 161105A: Swift-BAT refined analysis
  2. GRB 161105A: Enhanced Swift-XRT position
  3. Search for counterpart to IceCube-161103A with ANTARES
  4. GRB 161104A: GROND observations
  5. GRB 161105A: Swift detection of a burst
  6. GRB 161104A: Swift/UVOT Upper Limits
  7. GRB 161104A, Swift-BAT refined analysis
  8. GRB 161104A: Swift-XRT refined Analysis
  9. Fermi GBM Observations of IceCube-161103
  10. IceCube-161103: Swift-XRT observations
  11. GRB 161104A: Enhanced Swift-XRT position
  12. GRB 161104A: Swift detection of a short burst
  13. INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161103
  14. HAWC follow up of IceCube-161103
  15. GRB 161020A: Fermi GBM observation
  16. GRB 161023A: GROND Observations
  17. GRB 161023A: Swift-XRT afterglow detection
  18. GRB 161023A: TAROT La Silla observatory optical observations
  19. GRB 161023A: Zadko observatory - Gingin optical observations
  20. GRB 161023A: Watcher optical observations
  21. GRB 161023A: LCOGT-FTS optical observations
  22. GRB 161023A: A long GRB detected by INTEGRAL
  23. Swift Trigger 718919 is not an astrophysical event.
  24. GRB 161022A: Swift-BAT refined analysis
  25. GRB 161022A: RATIR Optical and NIR Observations
  26. GRB 161022A: Swift/UVOT Upper Limits
  27. GRB 161022A: Fermi GBM observation
  28. GRB 161022A: NOT optical observations
  29. GRB 161022A: Enhanced Swift-XRT position
  30. GRB 161022A: Swift-XRT refined Analysis
  31. IPN Triangulation of GRB 161020B
  32. GRB 161022A: TAROT Calern observatory optical observations
  33. GRB 161022A: Swift detection of a burst
  34. GRB 161020A: A long GRB detected by INTEGRAL
  35. GRB 161015A: further Swift-XRT follow-up observations
  36. Konus-Wind observation of GRB 161017A
  37. GRB161017A optical R band observations with SARA-RM
  38. GRB 161017A: Swift-BAT refined analysis
  39. GRB 161017A: Swift/UVOT Detection
  40. GRB 161017A: Swift-XRT refined Analysis
  41. GRB161017A: optical observations with 1-m LCOGT McDonald
  42. GRB 161017A: TNG optical observations
  43. GRB 161017A: Fermi GBM observation
  44. GRB 161017A: Enhanced Swift-XRT position
  45. GRB 161014A: Continued RATIR Optical and NIR Observations
  46. GRB 161015A: Swift/UVOT observations
  47. GRB 161017A: Swift detection of a burst with a bright optical afterglow
  48. GRB161017.74 MASTER-Net OT detection
  49. GRB161015A: AstroSat CZTI detection
  50. GRB 161014A: refined analysis of TSHAO optical observations
  51. GRB 161015A: Fermi GBM detection
  52. GRB161004A: Further analysis of the burst nature
  53. GRB 161014A: RATIR Optical and NIR Observations
  54. GRB 161014A: Fermi GBM observation
  55. GRB 161014A: Swift-XRT refined Analysis
  56. GRB 161014A: Swift-BAT refined analysis
  57. GRB 161014A: TNG optical observations
  58. GRB 161014A: AROMA-N Optical Observation
  59. GRB 161014A: Swift/UVOT Detection
  60. GRB161014A: NOT optical observations
  61. GRB 161014A: TSHAO optical observations
  62. GRB 161011A: RATIR Optical and NIR Observations
  63. GRB 161014A: Swift-XRT and UVOT afterglow detection
  64. GRB161014A: optical afterglow candidate with the LCOGT-FTS
  65. GRB 161014A: Swift detection of a burst
  66. GRB 161010A: Swift/UVOT Possible Detection
  67. GRB 161011A, Swift-BAT refined analysis
  68. GRB 161011A: TSHAO afterglow candidate
  69. GRB 161011A: Swift/UVOT Upper Limits
  70. GRB 161011A: Swift-XRT refined Analysis
  71. GRB 161011A: Enhanced Swift-XRT position
  72. GRB 161010A: Swift-XRT afterglow detection
  73. GRB 161011A: Swift detection of a burst
  74. GRB 161010A: a long GRB detected by INTEGRAL
  75. GRB 161007A: NOT optical observations
  76. GRB 161007A: AbAO optical observations
  77. GRB 161007A: Mondy optical observations
  78. GRB 161007A: Swift-BAT refined analysis
  79. GRB 161007A: Swift/UVOT Upper Limits
  80. GRB 161007A: Swift-XRT refined Analysis
  81. GRB 161007A: GTC observations
  82. GRB 161007A: Enhanced Swift-XRT position
  83. GRB 161004A: Maidanak optical observations
  84. GRB 161004A: refined analysis of TSHAO optical observations
  85. GRB 161007A: Swift detection of a burst
  86. GRB 160821A: Maisoncelles observatory optical observations
  87. GRB 160925A: Kottamia R-band observation
  88. GRB 160927A: GTC observations
  89. GRB 161004A: Swift-BAT refined analysis
  90. GRB 150302A: late-time imaging and optical afterglow confirmation
  91. GRB 161001A: IRSF upper limits
  92. GRB 161004B: Fermi GBM detection
  93. GRB 161004B: Swift/UVOT Upper Limits
  94. GRB 161004B: Swift-BAT refined analysis
  95. GRB 161004B: Swift-XRT refined Analysis
  96. GRB 161004A: RATIR Optical and NIR Observations
  97. GRB 161004B: Enhanced Swift-XRT position
  98. GRB 161004B: Swift detection of a burst
  99. GRB 161004A: SAO RAS optical upper limit
  100. GRB 161004A: Swift-XRT refined Analysis

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