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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"

19662 results found.

  1. GRB 170912A: Prompt enhanced Swift-XRT position
  2. GRB 170912A: Swift detection of a burst
  3. Konus-Wind observation of GRB 170906A
  4. Konus-Wind observation of GRB 170906C
  5. GRB 170906A: AstroSat CZTI(Veto) detection
  6. Swift Triggered on MAXI J1535-571
  7. GRB 170906A: Swift/UVOT Detection
  8. GRB 170906B: Swift/UVOT Upper Limits
  9. GRB 170906B: Swift-XRT refined Analysis
  10. LIGO/Virgo G299232: Swift-XRT sources
  11. GRB 170906B: Swift-BAT refined analysis
  12. GRB 170906B: Fermi GBM detection
  13. GRB 170906A: Fermi GBM detection
  14. GRB 170906A: Swift-BAT refined analysis
  15. GRB 170906A: Swift-XRT refined Analysis
  16. GRB 170906C: Swift/UVOT Upper Limits
  17. GRB 170906C: Swift-XRT refined Analysis
  18. GRB 170906C: Swift-BAT refined analysis
  19. GRB 170906C: Enhanced Swift-XRT position
  20. GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
  21. GRB 170906C: Swift-XRT observations
  22. GRB 170906A: Fermi-LAT detection
  23. GRB 170906C: Swift detection of a burst
  24. GRB 170906A: Enhanced Swift-XRT position
  25. GRB 170906B: Enhanced Swift-XRT position
  26. GRB 170906B: Swift detection of a burst
  27. GRB 170906A: Swift detection of a burst with an optical afterglow
  28. IPN Triangulation of GRB 170904A (long/very bright)
  29. LIGO/Virgo G299232: Lulin Observations of Possible OTs
  30. GRB 170904A: Insight-HXMT detection
  31. GRB 170903A: Fermi GBM observation
  32. LIGO/Virgo G299232: Maidanak observations of optical transient SwiftJ014008.5+343403.6
  33. LIGO/Virgo G299232: LOFAR follow-up
  34. Swift Trigger on continued activity of MAXI J1535-571
  35. GRB 170827A: LCO Observations
  36. GRB 170903A: Swift/UVOT Upper Limits
  37. GRB 170903A: UAFO /ISON optical upper limit
  38. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  39. GRB 170903A: Swift-XRT refined Analysis
  40. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  41. GRB 170903A: Enhanced Swift-XRT position
  42. GRB 170903A: Swift-BAT refined analysis
  43. GRB 170903A: Swift-XRT observations
  44. GRB 170903A: Swift detection of a burst
  45. Swift Triggers on MAXI J1535-571
  46. Swift Trigger 770431 (GRB 170902A) is a not a GRB
  47. GRB 170902A: Enhanced Swift-XRT position
  48. GRB 170902A: Swift detection of a burst or possible Galactic transient
  49. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
  50. LIGO/Virgo G298048: Continued X-ray monitoring and X-ray detection of GW170817 [erratum]]
  51. LIGO/Virgo G298048: Continued Gemini South observations
  52. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  53. LIGO/Virgo G299232: SVOM/2.16-m Optical Telescope Observations of Swift UVOT Transient
  54. LIGO/Virgo G299232: HAWC follow-up
  55. LIGO/Virgo G299232: Further Swift/UVOT Observations of Optical Transient SwiftJ014008.5+343403.6
  56. LIGO/Virgo G299232 : RATIR Optical and NIR Observations of Swift UVOT source
  57. LIGO/Virgo G299232: Liverpool Telescope observations
  58. LIGO/Virgo G299232: observations of the optical Transient Discovered by Swift/UVOT
  59. IPN Triangulation of GRB 170826B
  60. LIGO/Virgo G299232/PGWB170825.55: early MASTER observations of the Swift UVOT source position
  61. LIGO/Virgo G299232: GRAWITA Asiago/Copernico Telescope observations
  62. GRB170827A: Further GROND follow-up observations
  63. IPN Triangulation of GRB 170827B (short)
  64. LIGO/Virgo G299232: Optical Transient Discovery by Swift/UVOT
  65. GRB 170827A: Swift-XRT refined Analysis
  66. GROND observations of GRB170827A
  67. GRB 170823A: TAROT Calern observatory optical observations
  68. GRB 170827A, Swift-BAT refined analysis
  69. GRB 170827A: Swift/UVOT Upper Limits
  70. GRB 170827A: REM optical/NIR observations
  71. GRB 170827A: Swift detection of a burst
  72. LIGO/Virgo G299232: XRT Rank 2 source is not real
  73. LIGO/Virgo G299232: Swift/BAT data search
  74. GRB 170822A: AstroSat CZTI detection
  75. LIGO/Virgo G298048: Gemini-South Imaging and Spectroscopy
  76. Konus-Wind observation of GRB 170822A
  77. GRB 170823A: Swift-BAT refined analysis
  78. GRB 170823A: Swift detection of a burst
  79. LIGO/Virgo G298936: Swift/BAT data search
  80. GRB 170822A: RATIR Optical and NIR Observations
  81. GRB 170822A: AbAO optical upper limit
  82. GRB 170822A: Swift-BAT refined analysis
  83. GRB 170822A: Swift/UVOT Upper Limits
  84. LIGO/Virgo G298048: Chandra X-ray observations
  85. GRB 170822A: Swift-XRT refined Analysis
  86. GRB 170822A: Enhanced Swift-XRT position
  87. GRB 170822A:BOOTES-5/JGT optical afterglow candidate
  88. GRB 170822A: Swift detection of a burst
  89. LIGO/Virgo G298389: Swift/BAT data search
  90. LIGO/Virgo G298048: Possible X-ray detection with Swift
  91. LIGO/VIRGO G298048: ePESSTO optical spectra of the candidate optical/NIR counterpart of the gravitational wave G298048 in NGC4993.
  92. LIGO/VIRGO G298048: Expansion Velocity of SSS17a Consistent With Relativistic Merger Ejecta
  93. LIGO/Virgo G298048: optical spectral energy distribution of SSS17a
  94. LIGO/Virgo G298048: Continued Swift UV and X-ray Monitoring of SSS17a
  95. LIGO/VIRGO G298048: Swift UVOT detection and XRT upper limits
  96. LIGO/Virgo G298048: Swift/BAT data search
  97. IPN Triangulation of GRB 170816A (short/hard)
  98. LIGO/Virgo G297595: Swift-XRT sources
  99. GRB 170810A: VLA Detection
  100. GRB 170813A: Fermi GBM observation

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