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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').

27 results found.

  1. GRB 160303A: GTC imaging of possible host galaxy
  2. GRB 160303A: X-shooter spectroscopy
  3. GRB 160303A: Continued optical monitoring from NOT
  4. GRB 160303A: JCMT SCUBA-2 sub-mm observation
  5. GRB160303A: further GROND observations
  6. GRB 160303A: 9.8 GHz VLA upper limit
  7. GRB 160303A, Swift-BAT refined analysis
  8. GRB 160303A: MMT Optical Detection
  9. GRB 160303A: Continued RATIR Optical and NIR Observations
  10. GRB 160303A: GROND Optical Detection
  11. GRB 160303A: Observations from T150 OSN
  12. GRB 160303A: VLT/FORS2 afterglow obervations
  13. GRB 160303A: BOAO R-band Detection
  14. GRB 160303A: McDonald 2.1m CQUEAN Detection
  15. GRB 160303A SMA observation
  16. GRB 160303A iTelescope observation
  17. GRB 160303A: Swift-XRT refined Analysis
  18. GRB 160303A: Optical observations from the NOT
  19. GRB 160303A: Swift/UVOT Detection
  20. GRB 160303A: RAPTOR Observations During Gamma-Ray Emitting Interval
  21. GRB 160303A: Enhanced Swift-XRT position
  22. GRB 160303A: RATIR Optical and NIR Afterglow Detection
  23. GRB 160303A: MITSuME Akeno optical upper limits
  24. GRB 160303A: LCOGT-FTN optical observations
  25. GRB 160303A: MITSuME Okayama upper limits
  26. GRB 160303A: ISON-NM early optical early limits
  27. GRB 160303A: Swift detection of a burst, possibly short


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