Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

19565 results found.

  1. LIGO/Virgo G299232: INTEGRAL search for a prompt gamma-ray counterpart
  2. LIGO/Virgo G296853: VLT observations by GLGW Hunters
  3. LIGO/Virgo G299232 ANTARES search
  4. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  5. LIGO/Virgo G297595: Gemini and VLT observations by GLGW Hunters
  6. LIGO/Virgo G298936 TAROT/TZAC observations
  7. LIGO/Virgo G298936 : MAXI/GSC observations
  8. LIGO/Virgo G298048: MASTER Global-Net early optical observations and the Possible KiloNova SSS17a in NGC 4993 photometry and merging rate
  9. LIGO/Virgo G298048: Pierre Auger Observatory neutrino follow-up
  10. LIGO/Virgo G298048: HAWC follow-up
  11. LIGO/Virgo G298048: Gemini-South Imaging and Spectroscopy
  12. LIGO/Virgo G298048: MUSE Integral Field Observations
  13. LIGO/Virgo G298048: LOFAR follow-up
  14. LIGO/Virgo G297595: H.E.S.S. very-high energy gamma-ray follow-up
  15. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  16. LIGO/Virgo G298048: Results of the ASKAP search for fast radio bursts
  17. LIGO/Virgo G298389: CALET Observations
  18. LIGO/Virgo G298936 : Fermi-LAT search for a high-energy gamma-ray counterpart
  19. LIGO/Virgo G298936: Swift/BAT data search
  20. LIGO/Virgo G298048: Continued VLA monitoring at 6 GHz
  21. LIGO/Virgo G298936 ANTARES search
  22. LIGO/Virgo G298936: IceCube neutrino observations
  23. GRB 170822A: RATIR Optical and NIR Observations
  24. GRB 170822A: AbAO optical upper limit
  25. GRB 170822A: Swift/UVOT Upper Limits
  26. LIGO/Virgo G298048: Chandra X-ray observations
  27. GRB 170822A: Enhanced Swift-XRT position
  28. LIGO/Virgo G298048: CALET Observations
  29. GRB 170822A: Swift detection of a burst
  30. LIGO/Virgo G298048: MWA Observations of Error Region
  31. LIGO/Virgo G298048: VLA observation at 15 GHz
  32. LIGO/Virgo G298048 ANTARES search (2)
  33. LIGO/Virgo G298048: Kanata/HONIR NIR photometry of the possible counterpart of G298048
  34. LIGO/Virgo G298389: Swift/BAT data search
  35. LIGO/Virgo G298048: optical observations of CHILESCOPE observatory
  36. LIGO/Virgo G298048: Pan-STARRS izy photometry monitoring of SSS17a/DLT17ck
  37. LIGO/Virgo G298389 : Fermi-LAT search for a high-energy gamma-ray counterpart
  38. LIGO/Virgo G298048: VLA observation at 6 GHz
  39. LIGO/Virgo G298048: Continued VLA observations
  40. LIGO/Virgo G298389: INTEGRAL search for a prompt gamma-ray counterpart
  41. LIGO/Virgo G298048: Etelman Observatory observation of the potential LIGO EM counterpart SSS17a
  42. LIGO/Virgo G298048: GROND observations of candidate optical counterpart
  43. LIGO/Virgo G298389 ANTARES search
  44. LIGO/Virgo G298048: GROND photometry of candidate optical counterpart reveals brightening in the NIR
  45. LIGO/Virgo G298048: Additional Swope Observations of SSS17a
  46. LIGO/Virgo G298048: prior photometry from VISTA Hemisphere Survey
  47. LIGO/Virgo G298048: Archival 2MASS and Spitzer non-detections of the potential LIGO EM counterpart SSS17a
  48. LIGO/Virgo G298048: Archival VLA observations
  49. LIGO/Virgo G298048: AGILE-GRID analysis of the potential counterpart field
  50. LIGO/Virgo G298048: ASKAP search for fast radio bursts
  51. LIGO/Virgo G298048: TZAC TAROT Reunion (TRE) observations
  52. LIGO/Virgo G298048: Likelihood of SSS17a Being an Unrelated Extragalactic Transient in NGC 4993
  53. LIGO/Virgo G298048: REM optical/NIR observations
  54. LIGO/Virgo G298048, Fermi GBM trigger 524666471/170817.529: MAXI/GSC observations
  55. LIGO/Virgo G298048: Gemini-South Near-Infrared Photometry of the Optical Transient Candidate
  56. LIGO/Virgo G298048: VISTA/VIRCAM detection of candidate counterpart
  57. LIGO/Virgo G298048: Optical Candidate Shows No Evidence for Previous Activity in Archival SkyMapper Transient Survey Data
  58. LIGO/Virgo G298048: Las Cumbres Observatory Detection of The Possible Optical Counterpart in NGC 4993
  59. LIGO/Virgo G298048 : Fermi-LAT search for a high-energy gamma-ray counterpart
  60. LIGO/Virgo G298048 - Update on Fermi/GBM GRB 170817A Analysis
  61. LIGO/Virgo G298048: AGILE GRID observations
  62. LIGO/Virgo G298048: AGILE MCAL observations
  63. LIGO/Virgo G298048: Swift/BAT data search
  64. LIGO/Virgo G297595: Pierre Auger Observatory neutrino follow-up
  65. LIGO/Virgo G298048 ANTARES search
  66. GRB 170817A: Fermi GBM detection
  67. IPN Triangulation of GRB 170816A (short/hard)
  68. LIGO/Virgo G298048: Potential host galaxies from the GLADE catalog
  69. LIGO/Virgo G298048: Further analysis of a binary neutron star candidate with updated sky localization
  70. LIGO/Virgo G296853 TZAC TAROT observations
  71. LIGO/Virgo G297595: Subaru Hyper Suprime-Cam follow-up observations
  72. LIGO/Virgo G296853: Pierre Auger Observatory neutrino follow-up
  73. LIGO/Virgo G297595: Fermi GBM Observations
  74. LIGO/Virgo G297595: Swift/BAT data search
  75. LIGO/Virgo G297595 : Fermi-LAT search for high-energy gamma-ray counterpart
  76. GRB 170813A: Swift/UVOT Upper Limits
  77. LIGO/Virgo G297595 ANTARES search
  78. LIGO/Virgo G297595: INTEGRAL search for a prompt gamma-ray counterpart
  79. LIGO/Virgo G297595: IceCube neutrino observations
  80. GRB 170813A: RATIR Optical and NIR Observations
  81. GRB 170810A: AbAO optical upper limit
  82. GRB 170813A: Enhanced Swift-XRT position
  83. GRB 170813A: Swift detection of a burst
  84. LIGO/Virgo G296853: BOOTES-1 and GTC optical observations
  85. GRB 170810A: Swift/UVOT Detection
  86. GRB 170810A: Enhanced Swift-XRT position
  87. GRB 170810A: Swift detection of a burst with a bright optical counterpart
  88. LIGO/Virgo G296853: HAWC follow-up
  89. LIGO/Virgo G296853: Super-AGILE observations
  90. LIGO/Virgo G296853: no INTEGRAL data at the time of the event
  91. LIGO/Virgo G296853: Fermi-LAT search for high-energy gamma-ray counterpart
  92. LIGO/Virgo G296853: Fermi GBM Observations
  93. LIGO/Virgo G296853: Swift/BAT data search
  94. LIGO/Virgo G296853 ANTARES search
  95. GRB 170808B: Fermi GBM observation
  96. IPN Triangulation of GRB 170805A (short)
  97. GRB 170714A: ATCA detection of the radio counterpart
  98. GRB 170808A: MAXI/GSC detection
  99. GRB 170728B: TShAO, SAO RAS and AbAO optical observations
  100. GRB 170804A: LCO Observations

Advanced

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