Adaptive Optics imaging of Quasar Hosts

I. Marquez; P. Petitjean

Home/Archive/arXiv

arXiv · astro-ph/0203362

Adaptive Optics imaging of Quasar Hosts

I. Marquez·P. Petitjean

View original source ↗Read source document ↗Export metadata ↓

Abstract

We present the results of adaptive-optics imaging of 12 (z < 0.6) quasars in the H and K bands using the PUEO system mounted on the Canada-France-Hawaii telescope. The QSOs (m_V > 15.0) themselves are used as reference for the correction. The images, obtained under poor seeing conditions, have typical spatial resolution of FWHM ~ 0.3arcsec before deconvolution. The deconvolved H-band image of PG 1700+514 has a spatial resolution of 0.16arcsec and reveals a wealth of details on the companion and the host-galaxy. The comparison between the HST and CFHT images of PG 1700+514 shows how powerful and competitive ground-based AO can be. Close companions and obvious signs of interactions are found in 4 out of the 12 objects. The 2D images of 3 of the host-galaxies unambiguously reveal bars and spiral arms. The morphology of the other host-galaxies are difficult to determine from 1D surface brightness profiles and deeper images are needed that could be obtained with AO systems on 10m class telescopes. Analysis of mocked data shows that elliptical galaxies are always recognized as such, whereas disk hosts can be missed for small disk scale lengths and large QSO contributions.

Explore related subjects

astro-ph

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

I. Marquez, P. Petitjean. 2002-03-21. Adaptive Optics imaging of Quasar Hosts. https://arxiv.org/abs/astro-ph/0203362

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2024

Deformation procedure for scalar fields in cosmology

This work offers an extension of the deformation procedure introduced in field theory to the case of standard cosmology in the presence of real scalar field in flat space-time. The procedure is shown to work for many models, which give rise to several different cosmic scenarios, evolving under the presence of first-order differential equations which solve the corresponding equations of motion very appropriately.

astro-ph↗

arXiv2023

Does Unruh radiation accelerate the universe? A novel approach to dark energy

In braneworld scenario, the brane accelerates in the bulk, and hence it perceives a thermal bulk filled with Unruh radiation. We put forward that there may be an energy exchange between Unruh radiation in the bulk and the dark matter confined to the brane, which accelerates the universe.

astro-ph↗

arXiv2023

Dark Energy is the Cosmological Quantum Vacuum Energy of Light Particles-The Axion and the Lightest Neutrino

We uncover the general mechanism producing the dark energy(DE). This is only based on well known quantum physics and cosmology. We show that the observed DE originates from the cosmological quantum vacuum of light particles which provides a continuous energy distribution able to reproduce the data. Bosons give positive contributions to the DE while fermions yield negative contributions. As usual in field theory, ultraviolet divergences are subtracted from the physical quantities. The subtractions respect the symmetries of the theory and we normalize the physical quantities to be zero for the Minkowski vacuum. The resulting finite contributions to the energy density and the pressure from the quantum vacuum grow as log a(t) where a(t) is the scale factor, while the particle contributions dilute as 1/a^3(t), as it must be for massive particles. The DE equation of state P = w(z)H turns to be w(z)<-1 with w(z) asymptotically reaching the value -1 from below.A scalar particle can produce the observed DE through its quantum cosmological vacuum provided:(i)its mass is of the order of 10^{-3} eV = 1 meV,(ii) it is very weakly coupled and (iii) it is stable on the time scale of the age of the universe. The axion vacuum thus appears as a natural candidate. The neutrino vacuum (especially the lightest mass eigenstate) can give negative contributions to the DE. We find that w(z=0) is slightly below -1 by an amount ranging from [-1.5 10^{-3}] to [-8 10^{-3}] and we predict the axion mass to be in the range between 4 and 5 meV. We find that the universe will expand in the future faster than the de Sitter universe, as an exponential in the square of the cosmic time. DE arises from the quantum vacua of light particles in FRW cosmological space time in an analogous way to the Casimir effect in Minkowski spacetime with non trivial boundaries.

astro-ph↗