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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"

27261 results found.

  1. GRB 170830B CALET Gamma-Ray Burst Monitor detection
  2. Swift Triggered on MAXI J1535-571
  3. LIGO/Virgo G298048: LWA Detection
  4. GRB 170906A: Swift/UVOT Detection
  5. GRB 170906B: Swift/UVOT Upper Limits
  6. GRB 170906B: Swift-XRT refined Analysis
  7. LIGO/Virgo G299232: Swift-XRT sources
  8. GRB 170906C: optical observations
  9. GRB 170906B: Swift-BAT refined analysis
  10. GRB 170906B: Fermi GBM detection
  11. GRB 170906A: Fermi GBM detection
  12. GRB 170906A: Swift-BAT refined analysis
  13. GRB 170906A: Swift-XRT refined Analysis
  14. GRB 170906C: Swift/UVOT Upper Limits
  15. GRB 170906C: Swift-XRT refined Analysis
  16. LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of SSS17a in NGC4993.
  17. GRB 170906C: Swift-BAT refined analysis
  18. GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
  19. GRB 170829A: Insight-HXMT detection
  20. GRB 170906C: Swift-XRT observations
  21. GRB 170906A: Fermi-LAT detection
  22. GRB 170906C: Swift detection of a burst
  23. GRB 170906B: Swift detection of a burst
  24. GRB 170906A: Swift detection of a burst with an optical afterglow
  25. GRB 170901B: Insight-HXMT detection
  26. GRB 170904A: Insight-HXMT detection
  27. GRB 170903A: Fermi GBM observation
  28. LIGO/Virgo G298389: Fermi GBM Flux Upper Limits
  29. LIGO/Virgo G299232: LOFAR follow-up
  30. Swift Trigger on continued activity of MAXI J1535-571
  31. GRB 170903A: Swift/UVOT Upper Limits
  32. GRB 170903A: Swift-XRT refined Analysis
  33. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  34. GRB 170903A: Swift-BAT refined analysis
  35. GRB 170903A: Swift-XRT observations
  36. GRB 170903A: Swift detection of a burst
  37. Swift Triggers on MAXI J1535-571
  38. Swift Trigger 770431 (GRB 170902A) is a not a GRB
  39. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  40. GRB 170902A: Swift detection of a burst or possible Galactic transient
  41. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
  42. LIGO/Virgo G298048: Continued X-ray monitoring and X-ray detection of GW170817 [erratum]]
  43. LIGO/Virgo G299232/PGWB170825.55: MASTER archive images of the SIWFT/UVOT and MASTER OT J033744.97+723159.0 in NGC1343 galaxy before 25
  44. GRB 170831A: Fermi GBM detection
  45. GRB 170830A: Fermi GBM observation
  46. GRB 170830A: Astrosat CZTI detection
  47. LIGO/Virgo G298936: PIRATE observations
  48. LIGO/Virgo G299232: GRAWITA Campo Imperatore optical observations
  49. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  50. GRB 170830A: iTelescope optical observations
  51. LIGO/Virgo G299232: HAWC follow-up
  52. LIGO/Virgo G299232: Further Swift/UVOT Observations of Optical Transient SwiftJ014008.5+343403.6
  53. LIGO/Virgo G299232 : RATIR Optical and NIR Observations of Swift UVOT source
  54. IPN Triangulation of GRB 170826B
  55. LIGO/Virgo G298048: Konus-Wind observations
  56. GRB170827A: Further GROND follow-up observations
  57. LIGO/Virgo G299232 : MAXI/GSC observations
  58. GRB 170826B: Insight-HXMT detection
  59. IPN Triangulation of GRB 170827B (short)
  60. IPN Triangulation of GRB 170826A (short)
  61. LIGO/Virgo G299232: Optical Transient Discovery by Swift/UVOT
  62. LIGO/Virgo G298936: HAWC follow-up
  63. GRB 170827A: Swift-XRT refined Analysis
  64. GROND observations of GRB170827A
  65. GRB 170823A: TAROT Calern observatory optical observations
  66. LIGO/Virgo G299232: LOFAR follow-up
  67. GRB 170827A, Swift-BAT refined analysis
  68. GRB 170827A: Swift/UVOT Upper Limits
  69. GRB 170827A: Swift detection of a burst
  70. GRB 170826B: Fermi GBM detection
  71. LIGO/Virgo G299232: CALET Observations
  72. GRB 170826A: Fermi GBM detection
  73. LIGO/Virgo G298936: Astrosat CZTI upper limits
  74. LIGO/Virgo G299232: Astrosat CZTI upper limits
  75. LIGO/VIRGO G299232: Fermi GBM Observations
  76. LIGO/Virgo G299232 : Fermi-LAT search for high-energy gamma-ray counterpart
  77. LIGO/Virgo G298389: HAWC follow-up
  78. LIGO/Virgo G299232: Nearby Galaxies in the Localization Volume
  79. LIGO/Virgo G298936: CALET Observations
  80. GRB 170820A CALET Gamma-Ray Burst Monitor detection
  81. LIGO/Virgo G299232: Swift/BAT data search
  82. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations of NGC4993
  83. GRB 170822A: AstroSat CZTI detection
  84. LIGO/Virgo G299232: AGILE GRID observations
  85. LIGO/Virgo G299232: AGILE MCAL detection of a short gamma-ray candidate
  86. LIGO/Virgo G299232: INTEGRAL search for a prompt gamma-ray counterpart
  87. LIGO/Virgo G296853: VLT observations by GLGW Hunters
  88. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  89. LIGO/Virgo G299232: FOUND COINCIDENT IceCube neutrino observation
  90. LIGO/Virgo G297595: Gemini and VLT observations by GLGW Hunters
  91. GRB 170825A: AGILE/MCAL Detection
  92. LIGO/Virgo G298936 : MAXI/GSC observations
  93. LIGO/Virgo G298048: MASTER Global-Net early optical observations and the Possible KiloNova SSS17a in NGC 4993 photometry and merging rate
  94. LIGO/Virgo G298048: Pierre Auger Observatory neutrino follow-up
  95. LIGO/Virgo G298048: Near-infrared fading from Gemini-South
  96. LIGO/Virgo G298048: HAWC follow-up
  97. LIGO/Virgo G298048: Gemini-South Imaging and Spectroscopy
  98. LIGO/Virgo G298048: LWA radio observations
  99. GRB 170823A: Swift-BAT refined analysis
  100. LIGO/Virgo G298048: LOFAR follow-up

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