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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"

43959 results found.

  1. LIGO/Virgo G298048: LCO FLOYDS and Gemini Spectroscopy
  2. GRB 170921A: Nanshan optical upper limit
  3. GRB 170921A: Enhanced Swift-XRT position
  4. GRB 170921A: Swift-XRT refined Analysis
  5. GRB 170921A: TAROT Calern observatory optical observations
  6. GRB 170921B: Fermi GBM detection
  7. GRB 170921A: Swift detection of a burst
  8. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  9. LIGO/Virgo G298048: Limits from an FRB search of SSS17a with the Parkes 64m Radio Telescope
  10. LIGO/Virgo G298048: SSS17a photometry of CHILESCOPE observatory
  11. LIGO/Virgo G298048: Milliarcsecond imaging of the NGC 4993 central radio source
  12. Swift trigger 773082 is probably not astrophysical
  13. LIGO/Virgo G298048: TOROS photometry of SSS17a
  14. LIGO/Virgo G298048: Desert Fireball Network simultaneous optical observations of the SSS17a/DLT17ck.
  15. GRB 170912C: Insight-HXMT detection
  16. LIGO/VIRGO G298048: MeerKAT observations of SSS17a
  17. LIGO/Virgo G297595: NIR Observations following GW170814
  18. LIGO/Virgo G298048: Danish Telescope Observations of SSS17a/DLT17ck
  19. LIGO/Virgo G297595: PIRATE observations
  20. Fermi GBM trigger 527149931/170915272 is not a GRB
  21. LIGO/Virgo G298048: ATLAS pre-discovery limits 601 to 16 days before first detection of SSS17a/DLT17ck
  22. LIGO/Virgo G297595: LSGT observation of nearby galaxies
  23. GRB 170906A CALET Gamma-Ray Burst Monitor detection
  24. LIGO/Virgo G298048: AST3-2 observations of SSS17a/DLT17ck from Antarctica
  25. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  26. GRB 170912B: Swift/UVOT Upper Limits
  27. Fermi GBM trigger 526978609/170913289 is not a GRB
  28. GRB 170912B: Swift-BAT refined analysis
  29. LIGO/Virgo G297595: DLT40 follow-up observation
  30. GRB 170912A: Swift-BAT refined analysis
  31. GRB 170912A: Swift-XRT refined Analysis
  32. LIGO/Virgo G299232: Khureltogot observations
  33. GRB 170912B: Swift-XRT refined Analysis
  34. GRB 170912B: Fermi GBM observations
  35. LIGO/Virgo G298936: Konus-Wind observations
  36. LIGO/Virgo G299232: Konus-Wind observations
  37. GRB 170911A: Fermi GBM observation
  38. GRB 170912B: Enhanced Swift-XRT position
  39. LIGO/Virgo G299232: Pierre Auger Observatory follow-up
  40. LIGO/Virgo G298389: Pierre Auger Observatory neutrino follow-up
  41. GRB 170912B: Swift detection of a burst
  42. GRB 170912A: Enhanced Swift-XRT position
  43. GRB 170912A: Prompt enhanced Swift-XRT position
  44. GRB 170912A: Swift detection of a burst
  45. LIGO/Virgo G297595: Las Cumbres Observatory Optical Follow-Up
  46. Konus-Wind observation of GRB 170906A
  47. GRB 170911A: MAXI/GSC detection
  48. Konus-Wind observation of GRB 170906C
  49. GRB 170906A: AstroSat CZTI(Veto) detection
  50. GRB 170830B CALET Gamma-Ray Burst Monitor detection
  51. IBAS Alert nr. 7913 is not a real GRB
  52. Konus-Wind observation of GRB 170904A
  53. LIGO/Virgo G298048: VLA radio non-detection
  54. LIGO/Virgo G298048: VLBA upper limits at 8.7GHz for the GW counterpart SSS17a/DLT17ck on August 20-21 UT
  55. Swift Triggered on MAXI J1535-571
  56. LIGO/Virgo G298048: LWA Detection
  57. GRB 170906A: Swift/UVOT Detection
  58. GRB 170906B: Swift-XRT refined Analysis
  59. LIGO/Virgo G299232: Swift-XRT sources
  60. GRB 170906C: optical observations
  61. LIGO/Virgo G298048: ATCA observations of of SSS17a in NGC 4993
  62. GRB 170906B: Swift-BAT refined analysis
  63. GRB 170906B: Fermi GBM detection
  64. GRB 170906A: Fermi GBM detection
  65. GRB 170906A: Swift-BAT refined analysis
  66. GRB 170906C: COATLI Observations
  67. GRB 170906A: Swift-XRT refined Analysis
  68. GRB 170906C: Swift-XRT refined Analysis
  69. LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of SSS17a in NGC4993.
  70. GRB 170906C: Swift-BAT refined analysis
  71. GRB 170906C: Enhanced Swift-XRT position
  72. GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
  73. GRB 170829A: Insight-HXMT detection
  74. GRB 170906C: Swift-XRT observations
  75. GRB 170906A: Fermi-LAT detection
  76. GRB 170906C: Swift detection of a burst
  77. GRB 170906A: REM optical/NIR observations
  78. GRB 170906A: Enhanced Swift-XRT position
  79. GRB 170906B: Enhanced Swift-XRT position
  80. GRB 170906B: Swift detection of a burst
  81. GRB 170906A: Swift detection of a burst with an optical afterglow
  82. IPN Triangulation of GRB 170904A (long/very bright)
  83. GRB 170901B: Insight-HXMT detection
  84. GRB 170904A: Insight-HXMT detection
  85. LIGO/VIRGO G298048: Precise position of SSS17a based on HST and Gaia
  86. LIGO/VIRGO G298048: Radio detection of SSS17a at 6 GHz with the VLA
  87. LIGO/VIRGO G298048: Radio detection of SSS17a at 3GHz with the VLA/JAGWAR
  88. GRB 170903A: Fermi GBM observation
  89. LIGO/Virgo G299232: Maidanak observations of optical transient SwiftJ014008.5+343403.6
  90. LIGO/Virgo G298389: Fermi GBM Flux Upper Limits
  91. LIGO/Virgo G299232: LOFAR follow-up
  92. Swift Trigger on continued activity of MAXI J1535-571
  93. GRB 170827A: LCO Observations
  94. GRB 170903A: Swift/UVOT Upper Limits
  95. GRB 170903A: UAFO /ISON optical upper limit
  96. LIGO/Virgo G298048: e-MERLIN upper limits on 5 GHz compact emission from SSS17a
  97. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  98. GRB 170903A: Swift-XRT refined Analysis
  99. GRB 170903A: Host galaxy redshift from OSIRIS/GTC
  100. LIGO/Virgo G298048: Chandra X-ray Update on GW170817

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