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Related papers: Quasar Redshifts: The Intrinsic Component

200 papers

Quasars (Quasi Stellar Objects, abbreviated as QSOs) are still nowadays, close to half a century after their discovery, objects which are not completel y understood. In this brief review a description of the pending problems,…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-20 Martin Lopez-Corredoira

The cosmological redshifts z in the frequencies of spectral lines from distant galaxies as compared with their values observed in terrestrial laboratories, which are due to the scale factor a(t), frequently are interpret as a…

General Physics · Physics 2011-12-07 Branislav Vlahovic

There is a growing consensus that the emergence of quasars at high redshifts is related to the onset of galaxy formation, suggesting that the detection of concentrations of gas accompanying such quasars should provide clues about the early…

Astrophysics · Physics 2009-10-28 P. Petitjean , E. Pecontal , D. Valls-Gabaud , S. Charlot

Recent cosmological and astrophysical observations point out that the Universe is in accelerating expansion and filled up with non-luminous matter. In order to explain the observed large scale structures and this accelerating behavior one…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-23 S. Capozziello , G. Lambiase

It is known from some time that to explain some apparently {\it exotic events} observed in cosmic ray experiments, a deeply penetrating component in cosmic rays is needed, which, in turn, leads frequently to the nonexponential distributions…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Grzegorz Wilk , Zbigniew Wlodarczyk

I discuss and illustrate the development of large-scale structure in the Universe, emphasising in particular the physical processes and cosmological parameters that most influence the observationally accessible aspects of structure at large…

Astrophysics · Physics 2007-05-23 Simon D. M. White

Quasar feedback is a key ingredient in shaping galaxy evolution. A rare population of extremely red quasars (ERQs) at $z=2-3$ are often associated with high-velocity [O III]$\lambda5008$ outflows and may represent sites of strong feedback.…

Astrophysics of Galaxies · Physics 2024-08-13 Yilun Ma , Andy Goulding , Jenny E. Greene , Nadia L. Zakamska , Dominika Wylezalek , Yan-Fei Jiang

We present spectroscopic observations of six optical counterparts of intermediate luminosity X-ray sources (ULXs) around nearby galaxies. The spectra of the six objects show the presence of broad emission features. The identification of…

Astrophysics · Physics 2009-11-10 C. M. Gutierrez , M. Lopez-Corredoira

One of the models recently proposed to explain the origin of the ultra high energy cosmic rays assumes that these particles may be accelerated by the electromotive force around presently inactive quasar remnants. We study predictions for…

Astrophysics · Physics 2007-05-23 C. Isola , G. Sigl , G. Bertone

It is pointed out that the discrete velocities found by Tifft in galaxies are harmonically related to the discrete intrinsic redshifts found in quasars. All are harmonically related to the constant 0.062 +/- 0.001, and this is the fourth…

Astrophysics · Physics 2007-05-23 M. B. Bell

We have investigated the spatial distribution of quasars and its relationship with redshift by using the two-point correlation function, the variance of cell counts and the conditional density as a function of redshift. By comparing our…

Astrophysics · Physics 2007-05-23 P. Andreani , S. Cristiani , F. La Franca

Recent observational evidence in extra galactic astronomy, the interpretation of the nature of quasar redshift continues to be research interest. Spectrum observation of high redshift quasar is young in nature. Observational evidence…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-27 Arindam Mal , Sarbani Palit , Sisir Roy

The relation between quasar variability and parameters such as luminosity and redshift has been a matter of hot debate over the last few years with many papers on the subject. Any correlations which can be established will have a profound…

Astrophysics · Physics 2009-10-31 M. R. S. Hawkins

A fundamental prediction of relativistic cosmologies is that, due to the expansion of space, observations of the distant cosmos should be time dilated and appear to run slower than events in the local universe. Whilst observations of…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-08 Geraint F. Lewis , Brendon J. Brewer

Line-of-sight interactions of cosmic rays provide a natural explanation of the hard gamma-ray spectra of distant blazars, which are believed to be capable of producing both gamma rays and cosmic rays. For sources with redshifts z> 0.1,…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Warren Essey , Alexander Kusenko

We use photometric data, from the optical to the mm for a large sample of optically selected radio-quiet quasars, at low and high redshifts, to test emission models from circum-nuclear dusty torii around them. Model parameters, such as dust…

Astrophysics · Physics 2007-05-23 P. Andreani , A. Franceschini , G. L. Granato

"Diffuse" gamma rays consist of several components: truly diffuse emission from the interstellar medium, the extragalactic background, whose origin is not firmly established yet, and the contribution from unresolved and faint Galactic point…

Astrophysics · Physics 2015-06-24 I. V. Moskalenko , A. W. Strong , O. Reimer

Quasars are the most luminous sources in the Universe. They are currently observed out to redshift z ~ 7 when the Universe was less than one tenth of its present age. Since their discovery 50 years ago astronomers have dreamed of using them…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Paola Marziani , Jack W. Sulentic

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

Despite a general consensus in the astronomical community that all quasars are located at the distances implied by their redshifts, a number of observations still challenge this interpretation, possibly indicating that some subpopulation of…

Astrophysics · Physics 2009-11-11 E. Zackrisson