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arXiv · 1901.10032

Quasars: from the Physics of Line Formation to Cosmology

P. Marziani·E. Bon·N. Bon·A. del Olmo·M. L. Martínez-Aldama·M. D'Onofrio·D. Dultzin·C. A. Negrete·G. M. Stirpe
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Abstract

Quasars accreting matter at very high rates (known as extreme Population A [xA] or super-Eddington accreting massive black holes) provide a new class of distance indicators covering cosmic epochs from the present-day Universe up to less than 1 Gyr from the Big Bang. The very high accretion rate makes it possible that massive black holes hosted in xA quasars radiate at a stable, extreme luminosity-to-mass ratio. This in turns translates into stable physical and dynamical conditions of the mildly ionized gas in the quasar low-ionization line emitting region. In this contribution, we analyze the main optical and UV spectral properties of extreme Population A quasars that make them easily identifiable in large spectroscopic surveys at low-z (z < 1) and intermediate-z (2 < z < 2.6), and the physical conditions that are derived for the formation of their emission lines. Ultimately, the analysis supports the possibility of identifying a virial broadening estimator from low-ionization line widths, and the conceptual validity of the redshift-independent luminosity estimates based on virial broadening for a known luminosity-to-mass ratio.

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P. Marziani, E. Bon, N. Bon, A. del Olmo, M. L. Martínez-Aldama, M. D'Onofrio, D. Dultzin, C. A. Negrete, G. M. Stirpe. 2019-01-28. Quasars: from the Physics of Line Formation to Cosmology. https://arxiv.org/abs/1901.10032

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