SIMBAD references

2006MNRAS.372..246P - Mon. Not. R. Astron. Soc., 372, 246-252 (2006/October-2)

The relation between the optical spectral slope and the luminosity for 17 Palomar-Green quasi-stellar objects.


Abstract (from CDS):

Using 7.5-yr spectroscopic monitoring data of a sample of 17 Palomar-Green quasi-stellar objects (PG QSOs) (z = 0.061-0.371), we obtain the optical spectral slope for each object at all epochs by a power-law fit to the spectra in continuum bands. All of these 17 PG QSOs exhibit obvious spectral-slope variability. Most of the 17 objects show anticorrelation between the spectral slope and the rest-frame 5100-Å continuum flux, while five of them exhibit strong anticorrelation (correlation coefficient R larger than 0.5). For the ensemble of these 17 PG QSOs, a strong anticorrelation between the average spectral slope and the average rest-frame 5100-Å luminosity is found, while no correlation is found between the spectral slope and the Eddington ratio. A median anticorrelation between spectral-slope changes and continuum-flux variations is also found which indicates a hardening of the spectrum during bright phases. Accretion disc (jet) instability models with other mechanisms associated with changes in the accretion processes are promising.

Abstract Copyright: 2006 The Authors. Journal compilation © 2006 RAS

Journal keyword(s): techniques: spectroscopic - galaxies: active - galaxies: nuclei

Simbad objects: 18

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2006MNRAS.372..246P and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact