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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').

15 results found.

  1. GRB 081211B: Nearby cluster
  2. GRB 050813: Radio Observations
  3. GRB 050813: Gemini Spectra Revisited
  4. GRB 050813: Non-fading of afterglow candidate
  5. GRB050813: Gemini Imaging
  6. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  7. GRB 050813: Magellan detection of a high redshift galaxy cluster
  8. GRB050813: RTT150 optical observations
  9. GRB 050813: I-band observations
  10. GRB050813, SDSS pre-burst observations
  11. GRB 050813: KAIT optical limit
  12. GRB 050813: Swift-BAT refined analysis
  13. GRB 050813: Photometry of object in XRT error circle
  14. GRB 050813: Swift XRT afterglow localization
  15. GRB 050813: Possible Short Swift-BAT GRB


Download all Circulars as a .tar.gz archive:
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