Skip to main content
Due to the lapse in federal government funding, NASA is not updating this website. See the Operations FAQ for GCN impacts.
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

44 results found.

  1. Swift detection of the Soft Gamma Repeater PSR J1647-4552
  2. Fermi-LAT gamma-ray observations of IceCube-240808A
  3. Fermi trigger No 722462310: Global MASTER-Net observations report
  4. IceCube-230708A - IceCube observation of a high-energy neutrino candidate track-like event
  5. IceCube-220221A - IceCube observation of a high-energy neutrino candidate track-like event
  6. GRB 220117B: Swift/UVOT Upper Limits
  7. Fermi-LAT Gamma-ray Observations of IceCube-211023A
  8. IceCube-211023A - IceCube observation of a high-energy neutrino candidate track-like event
  9. Fermi-LAT Gamma-ray Observations of IceCube-210730A
  10. Fermi-LAT Gamma-ray Observations of IceCube-201120A
  11. AX J1846.4-0258: Swift-BAT refined analysis
  12. Swift Detection of an SGR-like flare from AX J1846.4-0258
  13. Fermi-LAT ANTARES 200127.79 coincidence: MASTER alert observation and presence of young pulsar close to error-box
  14. LIGO/Virgo S191110af: Potential pulsar counterparts
  15. Fermi-LAT Gamma-ray Observations of IceCube-191001A
  16. Trigger 896552: Swift detection of PSR B1055-52
  17. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  18. Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
  19. Fermi-LAT Gamma-ray Observations of IceCube-171106A
  20. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  21. Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552
  22. Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
  23. Swift Trigger on AXP CXOU J164710.2-455216
  24. GBM observation of SGR-like burst from the direction of PSR 1119-6127
  25. Trigger 706396: Swift detection of a short burst from PSR 1119-6127
  26. Trigger 648422: Swift possible detection of a source in NGC4552
  27. IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
  28. GRB130807A: Swift/UVOT observations
  29. GRB 120311A: Swift/UVOT Upper Limits
  30. GRB 120226A: Fermi-GBM and Fermi-LAT detections; LAT position retraction
  31. Swift detection of short bursts from PSR J1647-4552
  32. SGR J1834.9-0846: A Neutron Star in W41?
  33. Swift J1822.3-1606
  34. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  35. GRB 101008: Swift/UVOT Upper Limits
  36. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  37. GRB 060121: Confirmation of NIR Afterglow
  38. GRB 060121: Probable Detection of NIR Afterglow
  39. GRB 060121: candidate optical counterpart
  40. GRB060121: SARA Observations
  41. GRB 060121: optical observations
  42. GRB 060121: optical observations
  43. GRB050701: Swift-BAT Refined analysis
  44. Swift trigger 143708 is really GRB 050701

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