Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

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"

27264 results found.

  1. Konus-Wind observation of GRB 170906A
  2. GRB 170911A: MAXI/GSC detection
  3. Konus-Wind observation of GRB 170906C
  4. GRB 170830B CALET Gamma-Ray Burst Monitor detection
  5. Swift Triggered on MAXI J1535-571
  6. LIGO/Virgo G298048: LWA Detection
  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 170906C: optical observations
  12. GRB 170906B: Swift-BAT refined analysis
  13. GRB 170906B: Fermi GBM detection
  14. GRB 170906A: Fermi GBM detection
  15. GRB 170906A: Swift-BAT refined analysis
  16. GRB 170906A: Swift-XRT refined Analysis
  17. GRB 170906C: Swift/UVOT Upper Limits
  18. GRB 170906C: Swift-XRT refined Analysis
  19. LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of SSS17a in NGC4993.
  20. GRB 170906C: Swift-BAT refined analysis
  21. GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
  22. GRB 170829A: Insight-HXMT detection
  23. GRB 170906C: Swift-XRT observations
  24. GRB 170906A: Fermi-LAT detection
  25. GRB 170906C: Swift detection of a burst
  26. GRB 170906B: Swift detection of a burst
  27. GRB 170906A: Swift detection of a burst with an optical afterglow
  28. GRB 170901B: Insight-HXMT detection
  29. GRB 170904A: Insight-HXMT detection
  30. GRB 170903A: Fermi GBM observation
  31. LIGO/Virgo G298389: Fermi GBM Flux Upper Limits
  32. LIGO/Virgo G299232: LOFAR follow-up
  33. Swift Trigger on continued activity of MAXI J1535-571
  34. GRB 170903A: Swift/UVOT Upper Limits
  35. GRB 170903A: Swift-XRT refined Analysis
  36. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  37. GRB 170903A: Swift-BAT refined analysis
  38. GRB 170903A: Swift-XRT observations
  39. GRB 170903A: Swift detection of a burst
  40. Swift Triggers on MAXI J1535-571
  41. Swift Trigger 770431 (GRB 170902A) is a not a GRB
  42. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  43. GRB 170902A: Swift detection of a burst or possible Galactic transient
  44. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
  45. LIGO/Virgo G298048: Continued X-ray monitoring and X-ray detection of GW170817 [erratum]]
  46. LIGO/Virgo G299232/PGWB170825.55: MASTER archive images of the SIWFT/UVOT and MASTER OT J033744.97+723159.0 in NGC1343 galaxy before 25
  47. GRB 170831A: Fermi GBM detection
  48. GRB 170830A: Fermi GBM observation
  49. GRB 170830A: Astrosat CZTI detection
  50. LIGO/Virgo G298936: PIRATE observations
  51. LIGO/Virgo G299232: GRAWITA Campo Imperatore optical observations
  52. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  53. GRB 170830A: iTelescope optical observations
  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. IPN Triangulation of GRB 170826B
  58. LIGO/Virgo G298048: Konus-Wind observations
  59. GRB170827A: Further GROND follow-up observations
  60. LIGO/Virgo G299232 : MAXI/GSC observations
  61. GRB 170826B: Insight-HXMT detection
  62. IPN Triangulation of GRB 170827B (short)
  63. IPN Triangulation of GRB 170826A (short)
  64. LIGO/Virgo G299232: Optical Transient Discovery by Swift/UVOT
  65. LIGO/Virgo G298936: HAWC follow-up
  66. GRB 170827A: Swift-XRT refined Analysis
  67. GROND observations of GRB170827A
  68. GRB 170823A: TAROT Calern observatory optical observations
  69. LIGO/Virgo G299232: LOFAR follow-up
  70. GRB 170827A, Swift-BAT refined analysis
  71. GRB 170827A: Swift/UVOT Upper Limits
  72. GRB 170827A: Swift detection of a burst
  73. GRB 170826B: Fermi GBM detection
  74. LIGO/Virgo G299232: CALET Observations
  75. GRB 170826A: Fermi GBM detection
  76. LIGO/Virgo G298936: Astrosat CZTI upper limits
  77. LIGO/Virgo G299232: Astrosat CZTI upper limits
  78. LIGO/VIRGO G299232: Fermi GBM Observations
  79. LIGO/Virgo G299232 : Fermi-LAT search for high-energy gamma-ray counterpart
  80. LIGO/Virgo G298389: HAWC follow-up
  81. LIGO/Virgo G299232: Nearby Galaxies in the Localization Volume
  82. LIGO/Virgo G298936: CALET Observations
  83. GRB 170820A CALET Gamma-Ray Burst Monitor detection
  84. LIGO/Virgo G299232: Swift/BAT data search
  85. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations of NGC4993
  86. GRB 170822A: AstroSat CZTI detection
  87. LIGO/Virgo G299232: AGILE GRID observations
  88. LIGO/Virgo G299232: AGILE MCAL detection of a short gamma-ray candidate
  89. LIGO/Virgo G299232: INTEGRAL search for a prompt gamma-ray counterpart
  90. LIGO/Virgo G296853: VLT observations by GLGW Hunters
  91. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  92. LIGO/Virgo G299232: FOUND COINCIDENT IceCube neutrino observation
  93. LIGO/Virgo G297595: Gemini and VLT observations by GLGW Hunters
  94. GRB 170825A: AGILE/MCAL Detection
  95. LIGO/Virgo G298936 : MAXI/GSC observations
  96. LIGO/Virgo G298048: MASTER Global-Net early optical observations and the Possible KiloNova SSS17a in NGC 4993 photometry and merging rate
  97. LIGO/Virgo G298048: Pierre Auger Observatory neutrino follow-up
  98. LIGO/Virgo G298048: Near-infrared fading from Gemini-South
  99. LIGO/Virgo G298048: HAWC follow-up
  100. LIGO/Virgo G298048: Gemini-South Imaging and Spectroscopy

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov