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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 100615A: HST host detection and X-shooter redshift
  2. GRB 100615A: Additional Gemini/NIRI observations
  3. GRB 100615A: Chandra X-ray ToO Observation
  4. GRB 100615A: Gemini/NIRI Observations
  5. GRB 100615A: Swift/UVOT Upper Limits
  6. GRB 100615A: Fermi GBM detection
  7. GRB 100615A: Swift-BAT refined analysis
  8. GRB 100615A: Enhanced Swift-XRT position
  9. GRB 100615A: Swift-XRT refined analysis
  10. GRB 100615A: GROND observations, upper limits
  11. GRB 100615A: PAIRITEL NIR Upper Limits
  12. GRB 100615A: NTT/Ultracam imaging
  13. GRB 100615A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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