Fluctuations of the intergalactic ionization field at redshift z ~ 2

(Abridged) Aims. To probe the spectral energy distribution (SED) of the ionizing background radiation at z ~ 2 and to specify the sources contributing to the intergalactic radiation field. Methods. The spectrum of a bright quasar HS1103+6416 (zem = 2.19) contains five successive metal-line absorption systems at zabs = 1.1923, 1.7193, 1.8873, 1.8916, and 1.9410. The systems are optically thin and reveal multiple lines of different metal ions with the ionization potentials lying in the extreme ultraviolet (EUV) range (1 Ryd to 0.2 keV). For each system, the EUV SED of the underlying ionization field is reconstructed by means of a special technique developed for solving the inverse problem in spectroscopy. For the zabs = 1.8916 system, the analysis also involves the HeI resonance lines of the Lyman series and the HeI 504 A continuum, which are seen for the first time in any cosmic object except the Sun. Results. From one system to another, the SED of the ionizing continuum changes significantly, indicating that the intergalactic ionization field at z ~ 2 fluctuates at the scale of at least Delta_z ~ 0.004. This is consistent with Delta_z ~ 0.01 estimated from HeII and HI Lyman-alpha forest measurements between the redshifts 2 and 3.Comment: 29 pages, 18 figures, 3 tables, accepted for publication in A\&

Measurability of kinetic temperature from metal absorption-line spectra formed in chaotic media

We present a new method for recovering the kinetic temperature of the intervening diffuse gas to an accuracy of 10%. The method is based on the comparison of unsaturated absorption-line profiles of two species with different atomic weights. The species are assumed to have the same temperature and bulk motion within the absorbing region. The computational technique involves the Fourier transform of the absorption profiles and the consequent Entropy-Regularized chi^2-Minimization [ERM] to estimate the model parameters. The procedure is tested using synthetic spectra of CII, SiII and FeII ions. The comparison with the standard Voigt fitting analysis is performed and it is shown that the Voigt deconvolution of the complex absorption-line profiles may result in estimated temperatures which are not physical. We also successfully analyze Keck telescope spectra of CII1334 and SiII1260 lines observed at the redshift z = 3.572 toward the quasar Q1937--1009 by Tytler {\it et al.}.Comment: 25 pages, 6 Postscript figures, aaspp4.sty file, submit. Ap

Functioning of the Complex Metaphor “Politics is Animal World” in contemporary Mass-Media

Agafonova, O. I. Functioning of the Complex Metaphor “Politics is Animal World” in contemporary Mass-Media / O. I. Agafonova, M. S. Belozerova, S. Larini // Научный результат. Сер. Вопросы теоретической и прикладной лингвистики. - 2020. - Т.6, №1.-С. 3-11. - Doi: 10.18413/2313-8912-2020-6-1-0-1.The present article aims at the political discourse functioning as the medium for complex animal metaphor «POLITICS IS ANIMAL WORLD». The study of the animal metaphor in based on the material taken from the British and American web- based media. The metaphorical model is examined in the context of a discourse approach due to the intense interest to a man's mental world in the modern er

Argon and Silicon abundances in the damped Ly-alpha system I Zw 18

We show that the difference between the Ar and Si relative abundance ratio derived from FUSE absorption spectra and from the HII regions of I Zw 18 is a consequence of the microturbulent analysis applied to the absorption spectra. FUSE observations were performed with a large entrance aperture which fully covered the galaxy. This means that the observed profiles are averaged over the full body of I Zw 18, implying that large-scale velocity fields influence the absorption - line profiles. Taking this into account, we show that the absorption spectra are consistent with the same metal abundances as those derived from the HII regions. It follows that no significant ionization correction as suggested by Izotov and collaborators to describe metal contents in damped Ly-alpha systems (DLA) is required to model abundances in the neutral gas of I Zw 18 (a local DLA system). Using a mesoturbulent approach and applying the generalized radiative transfer equation to the ArI1048 and SiII1020 lines observed by Vidal-Madjar et al., we found that the profiles may be reproduced with log (Ar/Si) ~= - 0.8 and N(SiII) ~= 4 10^{15} cm^{-2}.Comment: 4 pages, 2 eps figure, submitted to A

The broad OVI absorber at z = 3.02 toward CTQ 325

We report on the multiphase absorption-line system detected at a redshift z = 3.021 in the spectrum of the quasi-stellar object CTQ 325 (z_em = 3.212). The system is displaced by ~14,000 km/s to the blue of the systemic velocity defined by the center of the symmetric OI quasar emission line. It consists of shallow and broad (~700 km/s, FWHM) absorption lines of HI 1215, CIV 1548,1550, and OVI 1032,1038, produced by collisionally ionized gas and of narrow absorption lines (FWHM < 20 km/s) of Ly-alpha, Ly-beta, ..., Ly-6, SiIII 1206, and CIII 977 produced by photoionized gas. Possible origins of this system are discussed.Comment: 6 pages, 4 figures, to appear in A&

Nitrogen-deficient and iron-rich associated absorbers with oversolar metallicities towards the quasar HE0141-3932

HE0141-3932 (zem=1.80) is a bright blue radio-quite quasar which reveals an emission line spectrum with an unusually weak Ly-alpha line. In addition, large redshift differences (Delta z=0.05) are observed between high ionization and low ionization emission lines. Absorption systems identified at z=1.78, 1.71, and 1.68 show mild oversolar metallicities (Z ~= 1-2Zsolar) and can be attributed to the associated gas clouds ejected from the circumnuclear region. The joint analysis of the emission and absorption lines leads to the conclusion that this quasar is seen almost pole-on. Its apparent luminosity may be Doppler boosted by ~10 times. The absorbing gas shows high abundance of Fe, Mg, and Al ([Fe, Mg, Al/C] ~= 0.15+/-0.10) along with underabundance of N ([N/C]<=-0.5). This abundance pattern is at variance with current chemical evolution models of QSOs predicting [N/C]>0 and [Fe/C]<0 at Z ~ Zsolar. Full details of this work are given in Reimers et al. (2005).Comment: 2 pages, to appear in the Proceed. of IAU Symp.228 "From Lithium to Uranium: Elemental Tracers of Early Cosmic Evolution", eds. V.Hill, P.Francois and F.Prima