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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').

16 results found.

  1. GRB 200215A: LCO Optical Upper Limits
  2. GRB 200215A: CALET Gamma-Ray Burst Monitor detection
  3. GRB 200215A: RATIR Optical Observations
  4. GRB 200215A: UKIRT H-band observations
  5. GRB 200215A: Swift-BAT refined analysis
  6. GRB 200215A: Swift-XRT refined Analysis
  7. GRB 200215A: Swift/UVOT Upper Limits
  8. GRB 200215A: Enhanced Swift-XRT position
  9. GRB 200215A: Optical observations form Calar Alto 2.2m
  10. GRB 200215A: Fermi GBM detection
  11. GRB 200215A: Liverpool Telescope upper limits
  12. GRB 200215A Possible host galaxy in PanSTARRS
  13. GRB 200215A: Nanshan/NEXT optical upper limit
  14. GRB 200215A: Swift detection of a burst
  15. GRB 200215A: Fermi GBM Final Real-time Localization
  16. GRB 200115A: Assy optical observations


Download all Circulars as a .tar.gz archive:
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