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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 180704A: Swift-XRT observations
  2. GRB 180704A: MASTER optical observation
  3. GRB 180704A: Swift detection of a burst
  4. GRB 180703B: Fermi-LAT detection
  5. GRB 180703A: Fermi-LAT detection
  6. GRB 180703A: Tiled Swift observations
  7. GRB 180630A: Swift/UVOT Detection
  8. GRB 180701A: MAXI/GSC detection
  9. GRB 180626C : GOTO optical observations
  10. GRB 180626B : GOTO optical observations
  11. GRB 180630A: Swift-BAT refined analysis
  12. GRB 180630A: Swift-XRT refined Analysis
  13. GRB 180630A: Fermi GBM detection
  14. GRB 180626C / Fermi trigger 551697835: MASTER inspection
  15. GRB 180630A: Enhanced Swift-XRT position
  16. GRB 180630A: Swift detection of a burst with an optical counterpart
  17. GRB 180626C: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 551697835)
  18. GRB 180626A: TSHAO optical upper limit
  19. Konus-Wind observation of GRB 180626A
  20. Konus-Wind observation of GRB 180626C
  21. GRB 180624A: NOT optical counterpart
  22. Konus-Wind observation of GRB 180626B
  23. GRB 180626A: RATIR Optical Observations
  24. IPN Triangulation of GRB 180626C (short)
  25. IPN Triangulation of GRB 180626B (short)
  26. GRB 180626A: Swift-BAT refined analysis
  27. GRB 180626A: KAIT Optical Upper Limit
  28. GRB 180626A: Swift-XRT refined Analysis
  29. GRB 180626A: COATLI Optical Detection
  30. GRB 180624A: LCO Haleakala observations
  31. GRB 180626A: Swift/UVOT Detection
  32. Konus-Wind observation of GRB 180623A
  33. GRB 180626A: RATIR Optical Detection
  34. GRB 180626A: LCO Haleakala observations
  35. GRB 180626A: ISON-MN optical observations
  36. GRB 180626A: Enhanced Swift-XRT position
  37. GRB 180626A: A long GRB detected by INTEGRAL
  38. GRB 180626A: Swift detection of a burst with an optical counterpart
  39. GRB 180623B: CALET Gamma-Ray Burst Monitor detection
  40. GRB 180624A: Swift-BAT refined analysis
  41. AT2018cow: Swift/BAT data search
  42. GRB 180624A: RATIR Optical Observations
  43. GRB 180624A: LBT/MODS redshift measurement
  44. GRB 180620B: AstroSat CZTI detection
  45. GRB 180620A: AstroSat CZTI detection
  46. GRB 180618A: AstroSat CZTI detection
  47. GRB 180613A: LCO Afterglow detection
  48. GRB 180624A: GROND observations
  49. GRB 180624A: LCO Siding Springs afterglow candidate
  50. GRB 180624A: MITSuME Okayama optical upper limits
  51. GRB 180624A: Swift-XRT refined Analysis
  52. GRB 180624A: Swift/UVOT Upper Limits
  53. GRB 180624A: Enhanced Swift-XRT position
  54. GRB 180623A: retraction of the Swift/UVOT Detection
  55. GRB 180623A: Swift-BAT refined analysis
  56. GRB 180624A: Swift detection of a burst
  57. GRB 180623A: Swift/UVOT Detection
  58. GRB 180623A: Swift-XRT refined Analysis
  59. GRB 180623A: Enhanced Swift-XRT position
  60. GRB 180623A: Swift detection of a burst
  61. GRB 180620B: Swift/UVOT Detection
  62. GRB 180620A iTelescope observation
  63. Konus-Wind observation of GRB 180620B
  64. Konus-Wind observation of GRB 180620A
  65. GRB 180620B: VLT/X-shooter redshift
  66. Konus-Wind observation of GRB 180618A (a short GRB with extended emission)
  67. GRB 180620B: Swift-BAT refined analysis
  68. GRB 180613A: Afterglow confirmation and added photometry
  69. GROND observations of GRB 180620B
  70. GROND observations of GRB 180620A
  71. GRB 180620B: Swift-XRT refined Analysis
  72. GRB 180618B: CALET Gamma-Ray Burst Monitor detection
  73. GRB 180620A: Swift-BAT refined analysis
  74. GRB 180620B: Enhanced Swift-XRT position
  75. GRB 180620B: Fermi GBM detection
  76. GRB 180620A: KAIT Optical Observations
  77. GRB 180620A: Xinglong-2.16m optical observations
  78. GRB 180618A: Swift/UVOT Detection
  79. GRB 180618A: TSHAO optical upper limit
  80. GRB 180620A: Swift-XRT refined Analysis
  81. GRB 180620B: Swift detection of a burst with an optical counterpart
  82. GRB 180620A: COATLI Detection and Light Curve
  83. GRB 180620A: Swift/UVOT Detection
  84. GRB 180618A: Xinglong-2.16m optical upper limit
  85. GRB 180620A: LCO McDonald observations
  86. GRB 180620A: Enhanced Swift-XRT position
  87. GRB 180620A: MASTER OT observation
  88. GRB 180620A: ISON-MN afterglow confirmation
  89. GRB 180620A: RATIR Optical Afterglow Detection
  90. GRB 180620A: Swift detection of a burst with an optical counterpart
  91. GRB 180618A: MASTER OT observation (a short GRB with extended emission)
  92. GRB 180618A: Swift-BAT refined analysis (a short GRB with extended emission)
  93. GRB 180611A: AstroSat CZTI detection
  94. GRB 180618A: Fermi GBM detection
  95. GRB 180618A: Swift-XRT refined Analysis
  96. GRB 180618A: LT prompt observations
  97. GRB 180618A: Enhanced Swift-XRT position
  98. GRB 180618A: Swift detection of a burst with an optical counterpart
  99. GRB 180614A: AbAO optical observations
  100. GRB 180614A: 1.5m OSN I-band observation

Advanced

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