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The accretion of a cloud of hydrogen at the surface of a small, heavy star produces a high energy mostly dissipated by electromagnetic radiation. The combination of the absorption and the redshift of this radiation by hydrogen explains all…

Astrophysics · Physics 2007-05-23 Jacques Moret-Bailly

The reliable theory of the evolution of heavy stars predicts the existence of a type of neutron stars which accrete a cloud of dirty hydrogen (accretors). Although they are very small (some hundreds of kilometres), the accretors should be…

Astrophysics · Physics 2016-08-30 Jacques Moret-Bailly

Spectra of quasars result primarily from interactions of natural light with atomic hydrogen. A visible absorption of a sharp and saturated spectral line in a gas requires a low pressure, so a long path without blushing as a cosmological…

Instrumentation and Methods for Astrophysics · Physics 2015-12-31 Jacques Moret-Bailly

Further investigation of data on quasars, especially in the ultraviolet band, yields an amazingly coherent narrative which we present in this paper. Quasars are characterised by strong continuum emission and redshifted emission and…

Astrophysics of Galaxies · Physics 2017-12-07 Nimisha G. Kantharia

Quasars, powered by gas accretion onto supermassive black holes, rank among the most energetic objects of the Universe. While they are thought to be ignited by galaxy mergers and affect the surrounding gas, observational constraints on both…

The cosmological background of ionizing radiation has been dominated by quasars once the Universe aged by ~2 billion years. At earlier times (redshifts z>3), the observed abundance of bright quasars declined sharply, implying that cosmic…

Astrophysics · Physics 2009-11-13 Abraham Loeb

Quasars are thought to be powered by the infall of matter onto a supermassive black hole at the centre of massive galaxies. As the optical luminosity of quasars exceeds that of their host galaxy, disentangling the two components can be…

The repartition of redshifts of the lines observed in the spectra of the quasars is generally considered as stochastic, but several authors showed that the difference of two redshifts is the product of an integer by a basic redshift zf =…

Astrophysics · Physics 2007-05-23 Jacques Moret-Bailly

Galaxies hosting z~2 quasars are the high-$z$ progenitors of today's massive `red-and-dead' galaxies. With close pairs of quasars at different redshifts, a background quasar can be used to study a foreground quasar's halo gas in absorption,…

Astrophysics · Physics 2011-02-11 J. Xavier Prochaska , Joseph F. Hennawi

The law introduced by Karlsson in spectroscopy of low-redshift quasars involves the Lyman spectrum of hydrogen atoms. Thus, it appears necessary to study the concepts introduced by a standard spectroscopy of quasars, studied here, with…

Instrumentation and Methods for Astrophysics · Physics 2016-03-15 Jacques Moret-Bailly

Internal line shifts in quasars spectra have played a more prominent role in our understanding of quasar structure and dynamics. The observed different redshift among broad hydrogen lines is still an amazing puzzle in the study of quasars.…

Astrophysics of Galaxies · Physics 2016-03-14 Dangbo Liu , Jianrong Shi , Junhan You

The quantification of the redshifts of the lines observed in the spectra of the quasars and the galaxies (the redshifts of their lines have some of the values given by the formula z=a+0.062m where a depends on the object, and m is an…

Astrophysics · Physics 2007-05-23 Jacques Moret-Bailly

Although dust is widely found in astrophysics, forming dust is surprisingly difficult. The proper combination of low temperature (<2000 K) and high density is mainly found in the winds of late-type giant and supergiant stars which, as a…

Astrophysics · Physics 2009-12-08 Martin Elvis , Massimo Marengo , Margarita Karovska

This paper gives an brief overview of the structure of hypothetical strange quarks stars (quark stars, for short), which are made of absolutely stable 3-flavor strange quark matter. Such objects can be either bare or enveloped in thin…

Solar and Stellar Astrophysics · Physics 2015-06-11 Fridolin Weber , Milva Orsaria , Hilario Rodrigues , Shu-Hua Yang

Cool neutral gas provides the raw material for all star formation in the Universe, and yet, from a survey of the hosts of high redshift radio galaxies and quasars, we find a complete dearth of atomic (HI 21-cm) and molecular (OH, CO, HCO+ &…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 S. J. Curran , M. T. Whiting

The large observed redshift of quasars has suggested large cosmological distances and a corresponding enormous energy output to explain the brightness or luminosity as seen at earth. Alternative or complementary sources of redshift have not…

General Physics · Physics 2016-09-07 Peter M. Hansen

Neutral hydrogen clouds with high column density detected towards distant quasars are unique probes of elemental nucleosynthesis and chemical evolution in the low metallicity regime. They provide measurements for several elements at very…

Astrophysics · Physics 2007-05-23 Paolo Molaro

Growing amount of data show evidence for statistical and apparent physical association between low-redshift galaxies and high-redshift quasi-stellar objects, suggesting noncosmological origin of their redshift and failure of classical…

Astrophysics · Physics 2007-05-23 Anatoly A. Svidzinsky

Quasars are galaxies hosting accreting supermassive black holes; due to their brightness, they are unique probes of the early universe. To date, only few quasars have been reported at $z > 6.5$ ($<$800 Myr after the Big Bang). In this work,…

High redshift quasars mark the locations where massive galaxies are rapidly being assembled and forming stars. There is growing evidence that quasar environments are metal-rich out to redshifts of at least five. The gas-phase metallicities…

Astrophysics · Physics 2007-05-23 F. Hamann , M. Dietrich , B. Sabra , C. Warner
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