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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').

11 results found.

  1. GRB 150728A: TNG optical observations
  2. GRB 150728A: Continued RATIR Optical Observations
  3. GRB 150728A: TSHAO optical observations
  4. GRB 150728A: RATIR Optical Observations
  5. GRB 150728A: AAO optical observations
  6. GRB 150728A: Swift-XRT refined Analysis
  7. GRB 150728A: Swift/UVOT Upper Limits
  8. GRB 150728A: Swift-BAT refined analysis
  9. GRB 150728A: FTN observations
  10. GRB 150728A: Enhanced Swift-XRT position
  11. GRB 150728A: Swift detection of a GRB


Download all Circulars as a .tar.gz archive:
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