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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"

20 results found.

  1. Possible radio detection of GRB160623A with the GMRT
  2. GRB 160623A: afterglow spectroscopy by GTC and independent redshift determination
  3. GRB 160623A: optical astrometry, photometry, and redshift
  4. GRB 160623A: Astrosat CZTI detection
  5. GRB 160623A: SAO RAS optical observations
  6. GRB 160623A: Possible detection of a radio afterglow at 15 GHz with AMI
  7. GRB 160623A CALET Gamma-Ray Burst Monitor detection
  8. GRB 160623A: SMA submm afterglow observations
  9. GRB 160625A - two different events?
  10. GRB 160623A: TSHAO optical observations
  11. GRB 160623A: MITSuME Ishigakijima Optical Observation
  12. GRB 160623A: Swift/UVOT Upper Limits
  13. GRB 160623A: RATIR Optical and NIR Observations, Afterglow Confirmation
  14. GRB 160623A: Mondy optical observations
  15. Swift detection of a dust-scattered halo around GRB 160623A
  16. GRB 160623A: Swift-XRT afterglow detection
  17. GRB 160623A: Fermi GBM detection/observation
  18. Konus-Wind observation of GRB 160623A
  19. GRB 160623A / Galactic transient: Fermi-LAT detection
  20. GRB 160623A: Swift ToO observations

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