Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

3051 results found.

  1. GRB 170311A: Swift detection of a burst
  2. GRB170306A: SALT observations
  3. LIGO/Virgo G275404: REM optical/NIR observations
  4. LIGO/Virgo G275404: Swift-XRT sources
  5. LIGO/Virgo G275404: SVOM/Mini-GWAC: Observations of initial skymap
  6. LIGO/Virgo G274296: J-GEM optical/NIR follow-up observations
  7. LIGO/Virgo G274296: iPTF Optical Transient Candidates
  8. LIGO/Virgo G274296: Asiago 1.82m Optical Observations
  9. IPN Triangulation of GRB 170219A (short/hard)
  10. LIGO/Virgo G274296: Pan-STARRS imaging and discovery of 70 transients
  11. Konus-Wind observation of GRB 170207A
  12. IPN Triangulation of GRB 170207A (long/very bright)
  13. LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
  14. GRB 170126A: AstroSat CZTI detection
  15. GRB 170126A: Swift detection of a burst with an optical counterpart
  16. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  17. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
  18. Trigger 731535: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  19. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  20. Trigger 731257: Another Swift-BAT detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  21. Trigger 731183: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  22. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  23. LIGO/Virgo G268556: ATLAS imaging of the skymap
  24. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  25. GRS 1716-249/GRO J1719-24/V2293 Oph, Swift-BAT refined analysis
  26. GRB161219.78 MASTER-Net OT detection
  27. GRB 161219B: Watcher optical observations
  28. IPN Triangulation of GRB 161218B (long/very bright)
  29. GRB 161219B: GROND afterglow observations
  30. GRB 161207A: POLAR observation
  31. GRB 161117A: MASTER-OAFA (Argentina) prompt OT observations
  32. GRB 161117B: Enhanced Swift-XRT position
  33. GRB 161117B: Swift detection of a burst
  34. GRB 161113A: Swift-XRT refined Analysis
  35. GRB 161105A: MASTER-IAC early optical observations
  36. GRB 161104A: Swift detection of a short burst
  37. GRB 161017A: MITSuME Akeno Optical Observation
  38. GRB 161007A: MASTER-net early optical observations
  39. GRB 160925A: Kottamia R-band observation
  40. GRB 160917A: Swift/UVOT Detection
  41. GRB 160917A: Mondy optical observations
  42. GRB 160912A: Fermi GBM detection
  43. GRB160821A: Astrosat CZTI (veto) detection
  44. GRB 160816A: MASTER inspection
  45. IPN Triangulation of GRB 160806A
  46. FACT follow-up of IceCube20160731
  47. Swift Trigger 704444 is probably not an astrophysical event.
  48. GRB 160623A: optical astrometry, photometry, and redshift
  49. GRB 160709A CALET Gamma-Ray Burst Monitor detection
  50. IPN Triangulation of GRB 160702A (short/hard)
  51. SGR 1935+2154: CALET Gamma-Ray Burst Monitor detections
  52. GRB 160705B: RATIR Optical and NIR Observations and Confirmation of the Fading Afterglow
  53. GRB 160705B: Swift-BAT refined analysis
  54. GRB 160705B: LT optical candidate
  55. GRB 160705B: Swift detection of a burst
  56. GRB 160625B: RTT150 optical observations
  57. GRB 160625B: Fermi-LAT refined analysis
  58. GRB 160623A: RATIR Optical and NIR Observations, Afterglow Confirmation
  59. GRB 160623A: Mondy optical observations
  60. GRB 160623A: Swift-XRT afterglow detection
  61. Konus-Wind observation of GRB 160607A
  62. GRB160601A: Kanata Telescope I- and Ks-bands upper limits
  63. Another Swift detection of SGR 1935+2154 (trigger #687124)
  64. GRB 160501A MASTER-NET early observations
  65. GRB 160501A: Swift detection of a burst
  66. MASTER search for counterpart to the IceCube event 67093193 (run 127853)
  67. LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
  68. GRB 160412A: Swift detection of a burst
  69. GRB 160410A: GROND optical detection
  70. LIGO/Virgo G211117: LOFAR follow-up
  71. GRB 160324A: CALET Gamma-Ray Burst Monitor detection
  72. GRB 160325A, Swift-BAT refined analysis
  73. GRB 160325A: Swift detection of a burst
  74. GRB 160321A: Swift detection of a probable burst
  75. LIGO/Virgo G211117: EWE for NOWT follow-up of northern sky
  76. Swift detection of a likely new SGR: SGR 0755-2933
  77. GRB 160314A: VLT/X-shooter redshift
  78. Swift trigger 677890 is noise
  79. GRB 160303A, Swift-BAT refined analysis
  80. GRB 160303A: VLT/FORS2 afterglow obervations
  81. GRB 160303A: Swift detection of a burst, possibly short
  82. GRB 160225.81/FERMI Trigg 478121069: MASTER OT J095503.19-355149.4 detection
  83. GRB 160221A: A long GRB detected by INTEGRAL
  84. GRB 160219A: Fermi GBM detection
  85. LIGO/Virgo G211117: LOFAR follow-up
  86. GRB 160131A: Mondy optcial observations
  87. GRB 160127A: TAROT La Silla observatory optical light curve
  88. LIGO/Virgo G211117: Preliminary VLA observation summary of PS15dpn
  89. LIGO/Virgo G211117: Further Swift-XRT sources
  90. LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
  91. GRB 160107A: MAXI/GSC detection
  92. GRB 160104A: MITSuME Okayama upper limits
  93. LIGO/Virgo G211117: Summary of Pan-STARRS transients
  94. LIGO/Virgo G211117: LOFAR follow-up
  95. GRB 160101A: MAXI/GSC detection
  96. LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
  97. LIGO/Virgo G211117: MAGIC very-high energy gamma-ray observations
  98. LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
  99. LIGO/Virgo G211117: iPTF Optical Transient Candidates
  100. GRB 151229A: Swift detection of a short burst

Advanced

Download all Circulars as a .tar.gz archive:
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov