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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').

20 results found.

  1. GRB 201221D: near-infrared observation with LBT
  2. GRB 201221D: 3.6m DOT optical observations
  3. GRB 201221D: SMA submm observation
  4. GRB 201221D: MMT MMIRS detection of marginally extended source
  5. GRB 201221D: LCOGT upper limits
  6. GRB 201221D: Fermi GBM detection
  7. GRB 201221D: Swift-BAT refined analysis
  8. GRB 201221D: Archival PS1 Imaging of the Putative Host Galaxy
  9. Short GRB201221D: High Redshift from OSIRIS/GTC
  10. Konus-Wind detection of GRB 201221D (short)
  11. GRB 201221D: Swift/UVOT Upper Limits
  12. GRB 201221D: Lowell Discovery Telescope afterglow observations
  13. GRB 201221D: FRAM-ORM optical limit
  14. GRB 201221D: Swift-XRT refined Analysis
  15. Swift GRB 201221D: Global MASTER-Net observations report
  16. GRB 201221D: Enhanced Swift-XRT position
  17. GRB 201221D: Nanshan/NEXT early optical upper limit
  18. GRB 201221D: candidate optical counterpart from the NOT
  19. GRB 201221D: Prompt enhanced Swift-XRT position
  20. GRB 201221D: Swift detection of a bright short burst

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