Models of infrared spectra of Sakurai's Object (V4334 Sgr) in 1997

Theoretical spectral energy distributions computed for a grid of hydrogen-deficient and carbon-rich model atmospheres have been compared with the observed infrared (1--2.5 $\mu$m) spectra of V4334 Sgr (Sakurai's Object) on 1997 April 21 and July 13. The comparison yields an effective temperature of \Tef = 5500 $\pm$ 200 K for the April date and \Tef = 5250 $\pm$ 200 K for July. The observed spectra are well fitted by Asplund et al. (1999) abundances, except that the carbon abundance is higher by 0.3 dex. Hot dust produces significant excess continuum at the long wavelength ends of the 1997 spectra. \keywords{Stars: individual: V4334 Sgr (Sakurai's Object) -- Stars: AGB and post-AGB evolution -- Stars: model atmospheres -- Stars: energy distributions -- Stars: effective temperatures}Comment: 6 pages, 7 eps figs, accepted for A

Spectral energy distribution for GJ406

Original article can be found at: http://www.aanda.org/----Copyright The European Southern ObservatoryPeer reviewe

Lessons from Non-Abelian Plasma Instabilities in Two Spatial Dimensions

Plasma instabilities can play a fundamental role in quark-gluon plasma equilibration in the high energy (weak coupling) limit. Early simulations of the evolution of plasma instabilities in non-abelian gauge theory, performed in one spatial dimension, found behavior qualitatively similar to traditional QED plasmas. Later simulations of the fully three-dimensional theory found different behavior, unlike traditional QED plasmas. To shed light on the origin of this difference, we study the intermediate case of two spatial dimensions. Depending on how the "two-dimensional'' theory is formulated, we can obtain either behavior.Comment: 15 pages, 10 figure

Modulation of Superconducting Properties by Ferroelectric Polarization in Confined FE-S-FE Films

We show that the electric polarization at the interface with ultrathin superconducting (S) films sandwiched between ferroelectric (FE) layers allows achievement of substantially stronger modulation of inner carrier density and superconducting transition temperature as compared to FE-S bilayers typically used in superconducting FETs. We find that not only the larger penetration depths but also the pairing symmetry should be responsible for the fact that the electric field effect in high temperature superconductors is much stronger than in conventional systems. Discussing the advantages of multilayers, we propose a novel design concept for superconducting electric field-effect transistors based on ferroelectric films.Comment: 5 pages RevTex4, 6 figure

A search for lithium in metal-poor L dwarfs

The aim of the project is to search for lithium in absorption at 6707.8 Angstroms to constrain the nature and the mass of the brightest low-metallicity L-type dwarfs (refered to as L subdwarfs) identified in large-scale surveys. We obtained low- to intermediate-resolution (R~2500-9000) optical (~560-770 nm) spectra of two mid-L subdwarfs, SDSSJ125637.13-022452.4 (SDSS1256; sdL3.5) and 2MASSJ162620.14+392519.5 (2MASS1626; sdL4) with spectrographs on the European Southern Observatory Very Large Telescope and the Gran Telescopio de Canarias. We report the presence of a feature at the nominal position of the lithium absorption doublet at 6707.8 Angstroms in the spectrum of SDSS1256, with an equivalent width of 66+/-27 Angstroms at 2.4 sigma, which we identify as arising from a CaH molecular transition based on atmosphere models. We do not see any feature at the position of the lithium feature in the spectrum of 2MASS1626. The existence of overlapping molecular absorption sets a confusion detection limit of [Li/H]=-3 for equivalently-typed L subdwarfs. We provided improved radial velocity measurements of -126+/-10 km/s and -239+/-12 km/s for SDSS1256 and 2MASS1626, respectively, as well as revised Galactic orbits. We implemented adjusting factors for the CaH molecule in combination with the NextGen atmosphere models to fit the optical spectrum of SDSS1256 in the 6200-7300 Angstroms range. We also estimate the expected Li abundance from interstellar accretion ([Li/H]=-5), place limits on circumstellar accretion (10^9 g/yr), and discuss the prospects of Li searches in cooler L and T subdwarfs.Comment: 9 pages, 6 figures, 4 tables, accepted to A&

The Abelianization of QCD Plasma Instabilities

QCD plasma instabilities appear to play an important role in the equilibration of quark-gluon plasmas in heavy-ion collisions in the theoretical limit of weak coupling (i.e. asymptotically high energy). It is important to understand what non-linear physics eventually stops the exponential growth of unstable modes. It is already known that the initial growth of plasma instabilities in QCD closely parallels that in QED. However, once the unstable modes of the gauge-fields grow large enough for non-Abelian interactions between them to become important, one might guess that the dynamics of QCD plasma instabilities and QED plasma instabilities become very different. In this paper, we give suggestive arguments that non-Abelian self-interactions between the unstable modes are ineffective at stopping instability growth, and that the growing non-Abelian gauge fields become approximately Abelian after a certain stage in their growth. This in turn suggests that understanding the development of QCD plasma instabilities in the non-linear regime may have close parallels to similar processes in traditional plasma physics. We conjecture that the physics of collisionless plasma instabilities in SU(2) and SU(3) gauge theory becomes equivalent, respectively, to (i) traditional plasma physics, which is U(1) gauge theory, and (ii) plasma physics of U(1)x U(1) gauge theory.Comment: 36 pages; 15 figures [minor changes made to text, and new figure added, to reflect published version

Atomic lines in infrared spectra for ultracool dwarfs

We provide a set of atomic lines which are suitable for the description of ultracool dwarf spectra from 10000 to 25000 \AA. This atomic linelist was made using both synthetic spectra calculations and existing atlases of infrared spectra of Arcturus and Sunspot umbra. We present plots, which show the comparison of synthetic spectra and observed Arcturus and Sunspot umbral spectra for all atomic lines likely to be observable in high resolution infrared spectra.Comment: 21 pages, 2 tables, 129 figures, figures are available only at http://www.astro.livjm.ac.uk/~hraj/spectralatlas/index.html, accepted to A&

Temporal logic model of performance in high school = Темпорально-логическая модель деятельности обучаемого в вузе

Pavlenko V. N., Tkachenko Y. M. Temporal logic model of performance in high school = Темпорально-логическая модель деятельности обучаемого в вузе. Journal of Education, Health and Sport. 2015;5(7):258-270. ISSN 2391-8306. DOI 10.5281/zenodo.19970http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%287%29%3A258-270https://pbn.nauka.gov.pl/works/584328http://dx.doi.org/10.5281/zenodo.19970Formerly Journal of Health Sciences. ISSN 1429-9623 / 2300-665X. Archives 2011 – 2014 http://journal.rsw.edu.pl/index.php/JHS/issue/archive Deklaracja.Specyfika i zawartość merytoryczna czasopisma nie ulega zmianie.Zgodnie z informacją MNiSW z dnia 2 czerwca 2014 r., że w roku 2014 nie będzie przeprowadzana ocena czasopism naukowych; czasopismo o zmienionym tytule otrzymuje tyle samo punktów co na wykazie czasopism naukowych z dnia 31 grudnia 2014 r.The journal has had 5 points in Ministry of Science and Higher Education of Poland parametric evaluation. Part B item 1089. (31.12.2014).© The Author (s) 2015;This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, Poland and Radom University in Radom, PolandOpen Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited.This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non commercialuse, distribution and reproduction in any medium, provided the work is properly cited.The authors declare that there is no conflict of interests regarding the publication of this paper.Received: 15.06.2015. Revised 05.07.2015. Accepted: 12.07.2015. TEMPORAL LOGIC MODEL OF PERFORMANCE IN HIGH SCHOOLТЕМПОРАЛЬНО-ЛОГИЧЕСКАЯ МОДЕЛЬ ДЕЯТЕЛЬНОСТИ ОБУЧАЕМОГО В ВУЗЕ V. N. Pavlenko, Y. M. TkachenkoВ. Н. Павленко, Ю. М. Ткаченко National Aerospace University «Kharkiv Aviation Institute», UkraineНациональный аэрокосмический университет им. Н. Е. Жуковского «ХАИ», Украина V.N. Pavlenko,NationalAerospaceUniversity«Kharkiv Aviation Institute», Ukraine Chkalova str. 17,Kharkiv,Ukraine, 61070E-mail: [email protected] Y.M. Tkachenko,NationalAerospaceUniversity«Kharkiv Aviation Institute», Ukraine Chkalova str. 17,Kharkiv,Ukraine, 61070E-mail: [email protected] Abstract: The one of the stages of the approach to the organization of computer decision support to determine the trajectory of training of students in universities, namely the synthesis of model student. For the synthesis of the student model used mathematical apparatus of temporal logic. The form of a software implementation, the student model is representation in the form of an intelligent agent. Further stages of developing a new approach based on the development of the model of the student group as a community of intelligent agents, and on the notion of the learning process of students in the form of multi-agent system. A multi-agent system will be used to support decision-making by different levels (deans, vice-rector for scientific and pedagogical work) in the event of disputes in the learning process of individual students and student groups. Keywords: student, student group, the trajectory of education, educational process, process model, multi-agent systems, intelligent agents, temporal logic.  Аннотация: изложен один из этапов реализации подхода к организации компьютерной поддержки принятия решений по определению траектории обучения студентов в ВУЗах, а именно синтез модели обучаемого. Для синтеза модели обучаемого использован математический аппарат темпоральной логики. Формой программной реализации модели обучаемого является его представление в виде интеллектуального агента. Дальнейшие этапы разрабатываемого подхода основаны на разработке модели студенческой группы как сообщества интеллектуальных агентов, и на представлении процесса обучения студентов в форме мультиагентной системы. Мультиагентная система будет использоваться для поддержки принятия решений руководителями разных уровней (деканами, проректорами по научно-педагогической работе) при возникновении спорных ситуаций в процессе обучения как отдельных студентов, так и студенческих групп. Ключевые слова: студент, студенческая группа, траектория обучения, образовательный процесс, процессная модель, мультиагентные системы, интеллектуальные агенты, темпоральная логика