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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"

37764 results found.

  1. GRB 180728A: discovery of the associated supernova
  2. GRB 180809A: further Swift/XRT observations
  3. GRB 180812A: Swift/UVOT Detection
  4. GRB 180812A: Swift-BAT refined analysis
  5. GRB 180812A: Fermi GBM detection
  6. GRB 180812A: Swift-XRT refined Analysis
  7. GRB 180809B: ePESSTO NTT NIR observations
  8. GRB 180812A: COATLI Detection and Light Curve
  9. GRB 180812A: Enhanced Swift-XRT position
  10. GRB 180812A: BOOTES-5/JGT optical afterglow detection
  11. GRB 180812A: Swift detection of a burst
  12. Konus-Wind observation of GRB 180809B
  13. MASTER: OT detection during two Fermi GBM triggers (555263883 and 555263883) error boxes inspection in 22.5 mag SDSS galaxy direction
  14. GRB 180809B: Swift-XRT refined Analysis
  15. GRB 180809B: CrAO optical observations
  16. GRB 180809B, Swift-BAT refined analysis
  17. GRB 180806A: AstroSat CZTI detection
  18. Swift Trigger 852625: Swift/BAT/XRT/UVOT observations
  19. GRB 180809B: Swift/UVOT Detection
  20. Konus-Wind observation of GRB 180806A
  21. GRB 180809A: Fermi GBM observation
  22. GRB 180809A: CALET Gamma-Ray Burst Monitor detection
  23. GRB 180809B: CALET Gamma-Ray Burst Monitor detection
  24. Swift Trigger 852625: a possible GRB
  25. GRB 180809B: VLT optical upper limits
  26. GRB180809B: MASTER Triple Independent Automatic OT Detection
  27. GRB 180809B: LCO Sutherland observations
  28. GRB 180809B: GROND Detection of the NIR Afterglow
  29. GRB 180809B: RATIR Optical Observations and Confirmation of Rapid Fading
  30. GRB 180805B: Teide LCO optical observations
  31. GRB 180809A: iTelescope optical limit
  32. GRB 180809A: Swift-XRT afterglow detection
  33. GRB 180809B: Swift detection of a burst with an optical afterglow
  34. GRB 180809A: Tiled Swift observations
  35. GRB 180809A: MAXI/GSC detection
  36. GRB 180728A: AstroSat CZTI detection
  37. GRB180806A: correction to Circular 23097
  38. GRB 180724A: AstroSat CZTI detection
  39. GRB 180723A: AstroSat CZTI detection
  40. GRB 180806A: NOT optical observations
  41. GRB 180806A: Swift-XRT afterglow detection
  42. GRB 180806A/180806.98: RATIR Optical Observations of MASTER OT J004613.05+242014.1
  43. GRB 180806A: Fermi GBM detection
  44. GRB 180806A/180806.94: Refined COATLI Photometry of MASTER OT J004613.05+242014.1
  45. GRB 180806A: Swift ToO observations
  46. GRB 180806.94: COATLI Detection of MASTER OT J004613.05+242014.1 and Confirmation of Fading
  47. GRB 180806.94: MASTER possible OT detection in Fermi GMB trigger 555287944 error box
  48. GRB 180805B: ESO/NTT optical observations
  49. GRB 180805B: COATLI Optical Observations
  50. GRB 180805B: 1.5m OSN I-band observation
  51. GRB 180805B: GOTO optical limits
  52. GRB 180805B: VLT optical and near-infrared observations
  53. GRB 180805B: MASTER optical late inspection short GRB with extended emission
  54. GRB 180805A: Swift-XRT refined Analysis
  55. GRB 180805B: Swift-XRT refined Analysis
  56. GRB 180805B: Swift-BAT refined analysis (short GRB with extended emission)
  57. GRB 180805A: Swift-BAT refined analysis
  58. GRB 180805B: Swift/UVOT Upper Limits
  59. GRB 180805B: Fermi GBM detection
  60. GRB 180805B: Enhanced Swift-XRT position
  61. GRB 180805B: Swift detection of a burst
  62. GRB 180805A: Enhanced Swift-XRT position
  63. GRB 180805A: Swift detection of a burst
  64. GMRT radio detection of GRB 180720B
  65. GRB 180727A: Swift/BAT spectral lag result
  66. Fermi Trigger 554765006: MASTER optical inspection
  67. GRB 180728B: GOTO optical search over IPN region
  68. Fermi GBM trigger 554730582/180731493 is not a GRB
  69. GRB 180728A: No evidence of SN in early VLT/X-shooter spectra
  70. GRB 180728A: A long GRB of the X-ray flash (XRF) subclass, expecting supernova appearance
  71. GRB 180728B: MASTER optical observations short GRB IPN error box
  72. GRB 180728A: Swift/UVOT Detection
  73. GRB 180701A/MAXI J2119-045: CALET Gamma-Ray Burst Monitor data search
  74. GRB 180727A: Swift/UVOT Upper Limits
  75. Konus-Wind observation of the bright nearby GRB 180728A
  76. Konus-Wind observation of GRB 180728B
  77. GRB 180715A: CALET CAL gamma-ray analysis
  78. GRB 180703B: CALET CAL gamma-ray analysis
  79. GRB 180728B: Fermi GBM detection
  80. IPN Triangulation of GRB 180728B (short)
  81. GRB 180728A: VLT/X-shooter redshift of a nearby energetic GRB
  82. GRB 180728A: Swift-BAT refined analysis
  83. GRB 180728A: Fermi GBM observation
  84. GRB 180728A: Swift-XRT refined Analysis
  85. GRB 180728A: Enhanced Swift-XRT position
  86. GRB 180728A: MASTER OT J165415.75-540239.27 is the Optical Counterpart of GRB
  87. GRB 180728A: Swift-XRT observations
  88. GRB 180728A: MASTER OT (= new object) detection
  89. GRB 180727A: Swift-BAT refined analysis
  90. GRB 180728A: Swift detection of a bright burst
  91. GRB 180727A: Swift-XRT refined Analysis
  92. GRB 180727A: Fermi GBM observation
  93. GRB 180727A: Swift detection of a burst
  94. GRB 180720B: CALET Gamma-Ray Burst Monitor detection
  95. NuSTAR observations of GRB 180720B
  96. GRB 180720B: OAJ optical observations
  97. GRB 180722B: Insight-HXMT/HE detection
  98. GRB 180724A: Insight-HXMT/HE detection
  99. GRB 180720B: AMI-LA 15.5 GHz observation
  100. GRB 180720B long follow up requested

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