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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').

13 results found.

  1. GRB 120211A : LOAO optical observations
  2. GRB 120211A: MITSuME Okayama Ks-band Observation
  3. GRB 120211A: GROND Upper limits
  4. GRB 120211A: MITSuME Okayama and Ishigakijima Optical upper limits
  5. GRB 120211A, optical observations
  6. GRB 120211A: Swift-XRT refined Analysis
  7. GRB 120211A: Swift/UVOT Upper Limits
  8. GRB 120211A: MASTER early optical observations
  9. GRB 120211A: Swift-BAT refined analysis
  10. GRB 120211A: MITSuME Okayama Ks-band upper limit
  11. GRB 120211A: Enhanced Swift-XRT position
  12. GRB 120211A - Faulkes Telescope South Observations
  13. GRB 120211A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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