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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').

21 results found.

  1. LIGO/Virgo S190521g: AstroSat CZTI upper limits
  2. LIGO/Virgo S190521g: No optical counterpart from SVOM/GWAC-F30 observations.
  3. LIGO/Virgo S190521g: No optical counterpart from SVOM/GWAC observations.
  4. LIGO/Virgo S190521g: Upper limits from Insight-HXMT/HE observations
  5. LIGO/Virgo S190521g: Upper limits from CALET observations
  6. LIGO/Virgo S190521g: Swift/BAT Counterpart Search
  7. LIGO/Virgo S190521g: No Counterparts in DDOTI/OAN Optical Observations
  8. LIGO/Virgo S190521g : Upper limits from Fermi-GBM observations
  9. LIGO/Virgo S190521g: Updated sky localization
  10. LIGO/Virgo S190521g: No candidate counterpart in Fermi-LAT observations
  11. LIGO/Virgo S190521r: Upper limits from AGILE-GRID observations
  12. LIGO/Virgo S190521g: No neutrino counterpart candidates in ANTARES search
  13. LIGO-Virgo S190521g: Upper Limits from AGILE-GRID observations
  14. IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo S190521g: No counterpart candidates in INTEGRAL SPI/ACS & IBIS/PICsIT prompt observations
  16. LIGO/Virgo S190521g: No counterpart candidates in AGILE-MCAL observations
  17. LIGO/Virgo S190521g: No counterpart candidates in HAWC observations
  18. LIGO/Virgo S190521g: Identification of a GW compact binary merger candidate
  19. LIGO/Virgo S190521g: INTEGRAL SPI/ACS prompt observation
  20. LIGO/Virgo S190521g Global MASTER-Net observations report
  21. LIGO/Virgo S190521g: IceCube Neutrino Search

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