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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').

16 results found.

  1. LIGO/Virgo S190421ar: Updated localization and classification from LIGO and Virgo data
  2. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  3. LIGO-Virgo S190421ar:Insight-HXMT/HE observation
  4. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  5. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  6. LIGO/Virgo S190421ar: Swift/BAT Counterpart Search
  7. LIGO/Virgo S190421ar/G330308: ANTARES neutrino search
  8. LIGO/Virgo S190421ar: MAXI/GSC Observations
  9. LIGO/Virgo S190421ar: INTEGRAL prompt observation
  10. LIGO/Virgo S190421ar: Fermi-GBM Observations
  11. LIGO/Virgo S190421ar Global MASTER-Net observations report
  12. LIGO/Virgo S190421ar: HAWC follow-up
  13. AT LIGO-Virgo S190421ar: AGILE GRID observations
  14. Subject: LIGO/VIRGO S190421ar: IceCube Neutrino Search
  15. LIGO/Virgo S190421ar: Identification of a GW compact binary merger candidate
  16. LIGO-Virgo S190421ar: AGILE MCAL observations

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