Catalog of candidates for quasars at 3 &lt; <Emphasis Type="Italic">z</Emphasis> &lt; 5.5 selected among X-Ray sources from the 3XMM-DR4 survey of the XMM-Newton observatory

We have compiled a catalog of 903 candidates for type 1 quasars at redshifts 3 < z < 5.5 selected among the X-ray sources of the “serendipitous” XMM-Newton survey presented in the 3XMMDR4 catalog (the median X-ray flux is ≈5 × 10^?15 erg s^?1 cm^?2 in the 0.5–2 keV energy band) and located at high Galactic latitudes |b| > 20° in Sloan Digital Sky Survey (SDSS) fields with a total area of about 300 deg². Photometric SDSS data as well infrared 2MASS and WISE data were used to select the objects. We selected the point sources from the photometric SDSS catalog with a magnitude error δ _mz′ < 0.2 and a color i′ ? z′ < 0.6 (to first eliminate the M-type stars). For the selected sources, we have calculated the dependences χ²(z) for various spectral templates from the library that we compiled for these purposes using the EAZY software. Based on these data, we have rejected the objects whose spectral energy distributions are better described by the templates of stars at z = 0 and obtained a sample of quasars with photometric redshift estimates 2.75 < z _phot < 5.5. The selection completeness of known quasars at z _spec > 3 in the investigated fields is shown to be about 80%. The normalized median absolute deviation (Δz = |z _spec ? z _phot|) is σ _Δz /(1+z _spec) = 0.07, while the outlier fraction is η = 9% when Δz/(1 + z _спек.) > 0.2. The number of objects per unit area in our sample exceeds the number of quasars in the spectroscopic SDSS sample at the same redshifts approximately by a factor of 1.5. The subsequent spectroscopic testing of the redshifts of our selected candidates for quasars at 3 < z < 5.5 will allow the purity of this sample to be estimated more accurately.     

Investigation of galaxy and quasar luminosity evolution in the model of standard cosmology

It is shown that the Hubble curvem(z) for galaxies and quasars averaged over a large volume of data forms in the first approximation a single continuous curve in the interval of red shifts 10^–2.5z4.5, which is satisfactorily described by the dependence .A large deviation of the observed mean dependence from the theoretical one predicted by the standard cosmology is explained by the evolution of the galaxy and especially quasar luminosity. The corresponding mid-statistical function of the absolute luminosity variation for the last 4/5 times of existence in the Universe is equal toM(z)–M(z ₀)=logz/z ₀+2z–0.4z ².The luminosity of the most far distant from the observed quasars on the average by 5–6 stellar magnitudes high than the luminosity of near galaxies and quasars. It is obtained that even the most far distant quasars atz5 are in the maximum of luminosity, or their extinction has just began, thus the quasar formation should be expected forz>(5–6). The relative rate of the luminosity decrease of galaxies and near quasars is rather accurately amounts in the recent epoch 7% per 10⁹ years. The obtained average Hubble curve of galaxies and quasars is evidently the main cause of their evolution in the Universe.     

Possible evidence for a massive black hole in a quasar with double redshift systems

With the aid of a simple black hole model of quasars we have found that the majority of the distinguishable emission lines in the spectrum of the quasar 1604+179 can be assigned to two redshift systems,z _r =3.712 andz _b =2.701. The appearance of double emission redshifts means that this quasar might be a massive black hole (of mass 10⁸ M M10¹¹ M ) with a ring-like emission line region (of radius 1 light-day r ₀1 light-year) in its accretion disk.     

Unknown selection effect simulates redshift periodicity in quasar number counts from Sloan Digital Sky Survey

Discrete Fourier analysis on the quasar number count, as a function of redshift, z, calculated from the Sloan Digital Sky Survey DR6 release appears to indicate that quasars have preferred periodic redshifts with redshift intervals of 0.258, 0.312, 0.44, 0.63, and 1.1. However the same periods are found in the mean of the zConf parameter used to flag the reliability of the spectroscopic measurements. It follows that these redshift periods must result from some selection effect, as yet undetermined. It does not signal any intrinsic (quantized) redshifts in the quasars in Sloan survey data. However this result does not rule out the possibility as found in earlier studies of other data.     

Periodicity in quasar redshifts or selection effects?

Peaks at high redshifts in individual samples of quasars can be explained as due to selection effects. It is concluded that peaks in quasar redshift distribution do not obey any generalformula that can constitute a periodicity, even though individual samples may favour some redshifts of smaller values, viz. z < 1.     

On an explanation of the discretization of the redshifts of quasars

We show that the relation ln(1+z)=0.206 proposed to describe the discretization of the spatial distribution of quasars is a consequence of observational selection and is predetermined by the choice of the photometric system (U, B, V, R), the ratios of the wavelengths of the emission lines of Mg II, C III, C IV, Ly and the absorption lines O VI (1035 å) of the quasars studied.Translated fromAstrofizika, Vol. 37, No. 4, 1994.In conclusion I express gratitude to L. V. Mirzoyan for constant interest and moral support in the course of the present work and to G. A. Arutyunyan for valuable advice.     

Astrophysical observations exclude the hypothesis on the universe expansion

It is known that the correlation between the observed visible luminositym(z), angular dimension (z) of galaxies on the red shiftz and theoretical relations of the standard cosmology is possible only under the assumption that the luminosity and object dimension evolution are equal toL(z) =L ₀(z + 1)^3.2 andl(z) =l ₀(z + 1)^–2, respectively. This evolution is hypothetical, since it is defined by a theory which is not confirmed by experience. In order to solve the problem on the reality of the Universe expansion, it is sufficient to prove or disprove these conclusions using methods of measurement independent of the theory. One of these methods consists of defining the dependence of the radiation spectra of galaxies and quasars onz which evidently is proportional to the spectrum of absolute luminosityL(, z). It has subsequently been shown that the spectrum form is practically independent of the red shift - i.e., it remains constant during the lifetime of galaxies and quasars. Consequently, to explain the luminosity increase required by the standard cosmology, it is necessary to admit a completely unreal entity (at all wavelengths of the optical spectrum increase) of the radiation spectral density of (z + 1)^3.2 times. We can conclude that in reality the luminosity evolution is either absent or its power index is smaller at least by an order of magnitude. It is likely, therefore, that the established is the result of an inadequate standard in cosmology.Another method is the use of the observed relations between the parameters ofL andl galaxies. A number of measurements made by different authors gives the relationlL ^a , where 0.33a1.6. It then follows thatl(z)(z + 1)^3.2a . This dependence of the galaxy dimension is inverse to the dependence predicted by the standard cosmology. Besides, in order to make a correlation between thel(z)(z + 1)^3.2a and measurements of (z), it is necessary that indices of the degree of luminosity evolution should be smaller by an order of magnitude.Thus, the luminosity increase and simultaneous decrease of galaxy and quasar dimensions predicted by the standard cosmolog are not confirmed by the direct astrophysical measurements. This discrepancy is the consequence of an incorrect hypothesis of Universe expansion and the relativistic cosmology based on it.     

Redshift cutoff and evolution of QSOs

In this paper I present a new evolution model of QSOs luminosity. The model is based on edges distribution of apparent magnitude-redshift of QSOs. After the quasars were formed, the luminosities were increasing until they attained their maximum value atz=2+a, where –0.1a0.6, then the luminosities were decreasing. If the QSOs originate from superconducting cosmic string of same initial massM _i 10¹² M , the formation epochs are different, most of the quasars start atz _cutoff5.6. The most luminous QSOs start at later epochz _cutoff5.15. The present sky survey echniques may give us the possibility to see the formation of QSOs at apparent magnitudem _V 22.5 by chance of 0.3%.     

The effect of luminosity-redshift correlation on the analysis of the angular size-redshift relation for radio galaxies

The variation of radio luminosity with redshift and its effect on the analysis of the angular size-redshift ( –z) relation for a bright radio source sample (s ₁₇₈ 10Jy) has been investigated. By assuming a power law dependence of luminosity on redshift of the formP (1 +z), it was found that 4.4 (with correlation coefficientr 0.99) for at leastz 0.3. Correction for such a strongP – (1 +z) correlation when considering the –z data for the sample led to a steeper –z slope. This could be explained by assuming linear size evolution of the formD (1 +z)^–n withn = 2.8 – 3.3 consistent with both theoretical results and those obtained for more homogeneous source samples.     

Ultraluminous quasars as a gravitational mesolensing effect

Two quasars SDSS J010013.02+280225.8 and J030642.51+185315.8 with redshifts z = 6.30 and z = 5.363 were recently discovered. Their apparent magnitudes in the standard cosmological model give the luminosities of L_bol ～ 4.3 × 10¹⁴L_⊙ and L_bol ～ 3.4 × 10¹⁴L_⊙. In the framework of modern concepts it is accepted that the energy release of quasars is provided by the accretion onto black holes with masses of 1.24 ± 0.19 × 10¹⁰M_⊙ and 1.07 ± 0.27 × 10¹⁰M_⊙. As within the standard cosmological model the ages of these objects are about one billion years, this creates serious difficulties for the scenario of formation of such objects. Here we interpret the ultra-high luminosities of quasars as the effect of lensing of their radiation by the foreground globular clusters or dwarf galaxies.     

A new examination of absorption line density in the Lα forest of QSOs

The distribution of the absorption lines in the L forest of QSOs is re-examined in relation to both absorption and emission redshifts by analyzing a sample consisting of 20 QSO L forests.On the one hand, the -value in the relationN(z _abs)=N ₀(1+z _abs) is re-estimated by applying the maximum likelihood (ML) method to all the L forests in our sample as a whole as well as to the forests for individual QSOs. The global estimated is 2.20±0.28 and both the quasars with highest and lowestz _em do not individually have a significant effect on it. A non-parametric test on the estimate of from individual QSOs shows that there is no significant difference between the numbers of positive and negative -values. This does not, therefore, favour the idea that for individual QSOsN(z _abs) decreases with increasingz _abs.On the other hand, the possible correlation between the absorption line density and the emission redshift of the QSO itself, which was found by Bianet al. (1986, 1988) and re-discovered independently by Tytler (1987), is shown once again not only by the largerz _em QSOs having larger mean density, but more importantly, at a rather high confidence level, by the fact that, at the same values ofz _abs, QSOs with largerz _em possess a greater number of L absorption lines.A discussion of the inverse effect suggests that it is still hard to say whether this effect really exists.     

Gigahertz-peaked spectrum (GPS) galaxies and quasars

The results of a comprehensive analysis of continuous radio spectra of a sample of Gigahertz-Peaked Spectrum (GPS) sources are reported. The sources are selected from a flux-density-complete sample (S _ν ≥ 200 mJy at 4.8 or 5 GHz) using multifrequency measurements of the RATAN-600 radio telescope and data from the CATS astrophysical catalogs support system. The analysis revealed a very small number (1–2%) of “classical” GPS objects, which is significantly less than the expected fraction of 10%. GPS galaxies are found to have narrower and steeper radio spectra than quasars. The low-frequency part of the spectrum is seen to become steeper with increasing redshift. Galaxies and quasars at the same z have comparable angular sizes, whereas their luminosities may differ by one order of magnitude. At large redshifts there is a deficit of objects with low (several GHZ) peak frequencies. The number of GPS galaxies decreases sharply with redshift, and most of them are found at z between 0.01 and 1.81. GPS quasars are found at large redshifts, from 0.11 to 3.99. A quarter of the sample consists of blazars whose spectra may temporarily have a convex shape when the object is in active state.     

On the existence of cosmological evolutionary effects

At the beginning of a series of papers concerning reality of various suggested cosmological evolutionary effects, the counts of quasars are examined. The recently reported counts of optically selected quasars (Green and Schmidt, 1978) probably have been biased by the use of distance-dependent morphological criteria of selection. The influence of this bias is to mimic cosmological evolution. The application of theK-correction for the counts of quasars is discussed. TheK-corrected, presumably unbiased counts of objects with ultraviolet excess and broad emission lines, including quasars and type 1 Seyfert galaxies, give the slopeb=0.6, i.e. a uniform radial distribution. Correctness of the latter sampling of data is dependent on the solution of the redshift problem and presupposes an inverse correlation between luminosity and intrinsic redshift.     

Periodicity versus selection effects in the redshift distribution of QSOs

Periodicities and selection effects in the redshift (z) distribution of QSOs have been debated for a long time in the literature. Here we show that peaks and troughs in the redshift distribution of three new samples, claimed to demonstrate the existence of a periodicity, can be interpreted in terms of known selection effects. This analysis confirms earlier findings that the presence of such selection effects seriously weakens any suggestion for periodicity of the form Δl n (1 + z) = constant.     

The implications of intrinsic luminosity evolution on the value of the density parameter (Ω) and the evolution of radio sizes of radio galaxies and quasars

The implications of the intrinsic luminosity evolution with cosmological epoch on the value of the density parameter () and evolution of radio sizes of extragalactic radio sources have been considered. It is shown that a power law evolution model of the sortP (1 +z) can be used to contrain the value of . In the presence of a strong luminosity evolution, the model yields an upper limit of 0.5.It is also shown that the angular diameter redshift ( – z) relation for quasars can be interpreted in terms of the assumed luminosity evolution combined with a luminosity-linear size correlation with little or no linear size evolution required. On the other hand, strong linear size evolution is needed to explain the – z data for radio galaxies independent of luminosity.     

Distribution of Doppler Redshifts of Associated Absorbers of SDSS Quasars

Doppler redshifts of a sample of Mg II associated absorbers of SDSS DR7 quasars are analysed. We find that there might be three Gaussian components in the distribution of the Doppler redshift. The first Gaussian component, with the peak being located at z _Dopp?=???0.0074, probably arises from absorbers with outflow histories observed in the direction close to jets of quasars. The second Gaussian component, with the peak being located at z _Dopp?=???0.0017, possibly arises from absorbers with outflow histories observed in the direction far away from jets of quasars. Whereas, the third Gaussian component, with the peak being located at z _Dopp?=???0.0004, might arise from the random motion of absorbers with respect to quasars.     

The pair of X-ray sources across NGC 4258: Its relation to intrinsic redshifts,ejection and quantization

The chance that the pair of X-ray sources observed across NGC 4258 is accidental can be calculated as 5×10^–6. The recent confirmation as quasars, and determination of the redshifts of the pair, atz=0.40 and 0.65 by E.M. Burbidge enables the final accidental probability of the configuration to be calculated as <4×10^–7. In addition there are a number of observations which indicate the central Seyfert galaxy is ejecting material from its active nucleus.The NGC 4258 association is compared to four other examples of close association of pairs of X-ray quasars with low redshift galaxies. It is concluded that in each of these five cases the chance of accidental association is less than one in a million. The ejection speed calculated from the redshift differences of the X-ray quasars is 0.12c. This agrees with the ejection velocity of 0.1c calculated in 1968 from radio quasars associated with low redshift peaks become narrower—simultaneously strengthening the ejection origin for quasars and the quantization property of their redshift     

A statistical study of the Lyman-Alpha absorption lines of nine quasars

We investigate the properties of the Lα absorption lines in the high resolution spectra of nine quasars, B2 1225+31.7, PKS 2126-158, Q 0002-422, Q 1453-423, PHL 957, PKS 0528-250, PKS 0805+046, PKS 1448-232 and PKS 1442+101. Their emission line redshift range is 2.20 ? z_em ? 3.54; a total of 350 Lα absorption lines cover the range 1.70 ? z_abs ? 3.54. Our analysis support the following conclusions; 1) the number density of Lα absorption lines is not significantly different in different quasars. 2) The number density does not vary significantly with redshift. 3) Their equivalent width spectrum does not vary significantly with redshift. 4) Their properties are the same whether in the wing of the Lα emission or in the continuum. 5) Their two-point correlation function is flat within the limit of resolution, which is different from the behaviour of galaxies. These results show that the Lα absorption lines in high-redshift quasars are very probably produced by intergalactic hydrogen clouds uniformly distributed throughout space.     

The absorption lines in the spectra of high redshift qsos

Based on the spectra of 4 high-redshift quasars (resolution 2A) obtained by us [1–5] using IPCS on the RGO Cassegrain spectrograph of the AAT, we point out the following. 1. Auto-correlation peaks at in PKS 0805+046 and PKS 1442+101 suggest that the large number of absorption lines shortward of L_α in high redshift quasars are due to absorption by hydrogen clouds. 2. The distribution of absorption lines and the correlation function of indicate that PKS 0528-250 may be an exception, requiring further observation. 3. Absorption redshift systems containing metallic lines may be produced by either matter ejected from the quasar, or an associated galaxy cluster or an intervening galaxy. 4. The randomness in the column density and the dispersion velocity deduced from the curve of growth of the pair supports the hypothesis that the pure L_α absorption comes from primitive hydrogen clouds in the early, exploding universe. 5. The number of hydrogen clouds per unit redshift interval is determined by the data of absorption lines of quasars with Z > 3.     

Search for the matter clumps in scalesZ ~ 1

The diagramV - log(1 +z _e ) as function of (, ) is considered for the quasars. HereV is the apparent visual magnitude,z _e is the emission line redshift, and are the equatorial coordinates. Two opposite extreme spots NE and SE are observed on the sky, where the inclination of the straight line fitting the dependenceV - log(1 +z _e ) is maximum and minimum. The coordinates of the centres of these extreme spots are ( _NE, _NE) = (282°, +42°) and ( _SE, _SE) = (70°, -38°) with errors 5°. A hypothesis of the Superattractor (SA) is proposed to explain such an effect. Two independent tests of this hypothesis are realized. First, the dependence or the frequency a of the absorbers in QSO spectra on (, ) is investigated. A region of the larger a is found. The coordinates of its centre are (, ) = (82°, - 10°) with error 5°. Second, the cases ofz _a >z _e are plotted in the Mercatorial projection (, ). The most of the casesz -z _e > 0.02 are concentrated within the circle with radiusR = 34° and centre (, ) = (50°, - 15°). The both anomalous regions overlap the Southern extreme spot around SE. The SA direction is (, ) = (67°, -21°) with errors about 12°. The redshift of SA isz _SA = 1.7 ± 0.3 that corresponds to the distancer _SA = (3100 ± 300)h ^–1 Mpc for the Hubble constantH ₀ = 75h kms^–1 Mpc^–1. The SA mass isM _SA ~ 10¹⁸-10²⁰ M . The orientation of the normal to the quasiperiodical large-scale sheet structure on the sky occurs near SA.