Infrared Classification and Luminosities For Dusty AGN and the Most Luminous Quasars

Mid-infrared spectroscopic measurements from the Infrared Spectrometer on Spitzer (IRS) are given for 125 hard X-ray AGN (14-195 keV) from the Swift Burst Alert Telescope sample and for 32 AGN with black hole masses from reverberation mapping. The 9.7 um silicate feature in emission or absorption defines an infrared AGN classification describing whether AGN are observed through dust clouds, indicating that 55% of the BAT AGN are observed through dust. The mid-infrared dust continuum luminosity is shown to be an excellent indicator of intrinsic AGN luminosity, scaling closely with the hard X-ray luminosity, log vLv(7.8 um)/L(X) = -0.31 +- 0.35 and independent of classification determined from silicate emission or absorption. Dust luminosity scales closely with black hole mass, log vLv(7.8 um) = (37.2 +- 0.5) + 0.87 log BHM for luminosity in erg per sec and BHM in solar masses. The 100 most luminous type 1 quasars as measured in vLv(7.8 um) are found by comparing Sloan Digital Sky Survey optically discovered quasars with photometry at 22 um from the Wide-Field Infrared Survey Explorer, scaled to rest frame 7.8 um using an empirical template determined from IRS spectra. The most luminous SDSS/WISE quasars have the same maximum infrared luminosities for all 1.5 < z < 5, reaching total infrared luminosity L(IR) = 10^14.4 solar luminosities. Comparing with Dust Obscured Galaxies from Spitzer and WISE surveys, we find no evidence of hyperluminous obscured quasars whose maximum infrared luminosities exceed the maximum infrared luminosities of optically discovered quasars. Bolometric luminosities L(bol) estimated from rest frame optical or ultraviolet luminosities are compared to L(IR).Comment: accepted for publication in The Astrophysical Journa

Physics and Earth Science User Communities of Armenian National Grid Initiative

The main purpose of this article is to present the results and activities of physics and earth sciences heavy user communities of Armenian National Grid Initiative (ArmNGI) using computational or storage resources of Armenian National Grid infrastructure (ArmGrid)

Infrared Spectra and Spectral Energy Distributions for Dusty Starbursts and AGN

We present spectroscopic results for all galaxies observed with the Spitzer Infrared Spectrograph (IRS) which also have total infrared fluxes f(ir) measured with the Infrared Astronomical Satellite (IRAS), also using AKARI photometry when available. Infrared luminosities and spectral energy distributions (SEDs) from 8 um to 160 um are compared to polycyclic aromatic hydrocarbon (PAH) emission from starburst galaxies or mid-infrared dust continuum from AGN at rest frame wavelengths ~ 8 um. A total of 301 spectra are analyzed for which IRS and IRAS include the same unresolved source, as measured by the ratio fv(IRAS 25 um)/fv(IRS 25 um). Sources have 0.004 < z < 0.34 and 42.5 < log L(IR) < 46.8 (erg per s) and cover the full range of starburst galaxy and AGN classifications. Individual spectra are provided electronically, but averages and dispersions are presented. We find that log [L(IR)/vLv(7.7 um)] = 0.74 +- 0.18 in starbursts, that log [L(IR)/vLv(7.7 um)] = 0.96 +- 0.26 in composite sources (starburst plus AGN), that log [L(IR)/vLv(7.9 um)] = 0.80 +- 0.25 in AGN with silicate absorption, and log [L(IR)/vLv(7.9 um)] = 0.51 +- 0.21 in AGN with silicate emission. L(IR) for the most luminous absorption and emission AGN are similar and 2.5 times larger than for the most luminous starbursts. AGN have systematically flatter SEDs than starbursts or composites, but their dispersion in SEDs overlaps starbursts. Sources with the strongest far-infrared luminosity from cool dust components are composite sources, indicating that these sources may contain the most obscured starbursts.Comment: Accepted for publication in The Astrophysical Journa

Comparing Ultraviolet and Infrared-Selected Starburst Galaxies in Dust Obscuration and Luminosity

We present samples of starburst galaxies that represent the extremes discovered with infrared and ultraviolet observations, including 25 Markarian galaxies, 23 ultraviolet luminous galaxies discovered with GALEX, and the 50 starburst galaxies having the largest infrared/ultraviolet ratios. These sources have z < 0.5 and cover a luminosity range of ~ 10^4. Comparisons between infrared luminosities determined with the 7.7 um PAH feature and ultraviolet luminosities from the stellar continuum at 153 nm are used to determine obscuration in starbursts and dependence of this obscuration on infrared or ultraviolet luminosity. A strong selection effect arises for the ultraviolet-selected samples: the brightest sources appear bright because they have the least obscuration. Obscuration correction for the ultraviolet-selected Markarian+GALEX sample has the form log[UV(intrinsic)/UV(observed)] = 0.07(+-0.04)M(UV)+2.09+-0.69 but for the full infrared-selected Spitzer sample is log[UV(intrinsic)/UV(observed)] = 0.17(+-0.02)M(UV)+4.55+-0.4. The relation of total bolometric luminosity L_{ir} to M(UV) is also determined for infrared-selected and ultraviolet-selected samples. For ultraviolet-selected galaxies, log L_{ir} = -(0.33+-0.04)M(UV)+4.52+-0.69. For the full infrared-selected sample, log L_{ir} = -(0.23+-0.02)M(UV)+6.99+-0.41, all for L_{ir} in solar luminosities and M(UV) the AB magnitude at rest frame 153 nm. These results imply that obscuration corrections by factors of two to three determined from reddening of the ultraviolet continuum for Lyman Break Galaxies with z > 2 are insufficient, and should be at least a factor of 10 for M(UV) about -17, with decreasing correction for more luminous sources.Comment: accepted for publication in The Astrophysical Journa

Star Formation Rates for Starburst Galaxies from Ultraviolet, Infrared, and Radio Luminosities

Star formation rates (SFR) are compared as determined from mid-infrared 7.7 um PAH luminosity [SFR(PAH)], from 1.4 GHz radio luminosity [SFR(radio)], and from far ultraviolet luminosity [SFR(UV)] for a sample of 287 starburst galaxies with z < 0.5 having Spitzer IRS observations. The previously adopted relation log [SFR(PAH)] = log [vLv(7.7 um)] - 42.57+-0.2, for SFR in solar masses per year and vLv(7.7 um) the luminosity at the peak of the 7.7 um PAH feature in ergs per s, is found to agree with SFR(radio). Comparing with SFR(UV) determined independently from ultraviolet observations of the same sources with the GALEX mission (not corrected for dust extinction), the median log [SFR(PAH)/SFR(UV)] = 1.67, indicating that only 2% of the ultraviolet continuum typically escapes extinction by dust within a starburst. The ratio SFR(PAH)/SFR(UV) depends on infrared luminosity, with form log [SFR(PAH)/SFR(UV)]= (0.53+-0.05)log Lir - 4.11+-0.18, for Lir in solar luminosities. We also find that the ratio SFR(PAH)/SFR(UV) is similar to that in infrared-selected starbursts for a sample of Markarian starburst galaxies originally selected using optical classification, which implies that there is no significant selection effect in SFR(PAH)/SFR(UV) using starburst galaxies discovered by Spitzer. These results indicate that SFRs determined with ultraviolet luminosities require dust corrections by a factor of ~ 10 for typical local starbursts but this factor increases to > 700 for the most luminous starbursts at z ~ 2.5. With this amount of extinction, the optical magnitude of a starburst having fv(7.7 um) of 1 mJy should be V ~ 25.6.Comment: Final version as published, including minor corrections made in proo

Piano lesson. The development of the student independent working skills

Fortepijono pamokoje mokytojas vysto savo ugdytinių muzikinius gabumus, turtindamas juos žiniomis, tobulindamas muzikos atlikimo įgūdžius bei meninius sugebėjimus, ugdydamas instrumento valdymo gabumus formuoja jų pasirengimą savarankiškam darbui. Taip pedagogas tampa pagrindiniu mokymo proceso organizatoriumi, informacijos teikėju, o mokiniai formuoja įgūdžius padedančius jiems mokytis bei savarankiškai dirbti. Vistik jei mokinys tik stebės ir tik stengsis atsiminti pedagogo pasakytas taisykles bei išvadas - negalima tikėtis gerų mokymosi rezultatų. Tam, kad mokinys pamokos metu būtų susikaupęs bei aktyvus jis turi būti skatinamas savo mokytojo, taip formuosis jo požiūris į mokymąsi. Pedagogas turi padėti atsiskleisti mokinio sugebėjimams bei jų raiškai, išugdyti poreikį mokytis ir dirbti savarankiškai, kadangi nuo jo priklausys ar mokinys eis tobulėjimo keliu. Todėl šio darbo problema formuojama probleminiu klausimu - koks pedagogo indėlis ugdant mokinių įgūdžius savarankiškam darbui?In a piano lesson the teacher develops the student‘s musical talents by enriching them with knowledge, develops the student‘s performance skills and artistic abilities. While developing the instrument mastering skills, the teacher forms the student‘s preparation for independent work. This is how the teacher becomes the main organizer of the learning process and provider of the information. The students form skills, that help them learn and work independently. Although, if the student only observes and tries to remember the rules and conclusions told by the teacher, great studying results can not be accomplished. To keep the student fully concentrated and active, he has to be encouraged by his teacher. That will form his attitude towards the learning process. The teacher has to help reveal the student‘s abilities and a need to study and work independently since this leads to the student‘s improvement. That‘s why the problem of this thesis is formed with a problematic question – what is the teacher‘s input in developing students‘skills for independent work?Vytauto Didžiojo universiteta

Zaměstnanost žen před a během pandemie Covid-19: Případ Arménie

The Covid-19 pandemic had a significant impact on female labor market outcomes in Armenia. This study uses Armenian Labor Force Surveys data from 2019, 2020, and 2021 to examine women's probability of working in the labor market during the Covid-19 pandemic that started in March 2020. Employing the linear probability model (LPM) approach, I find that 30-39 years old women with vocational education had a lower probability of working during specific quarters in 2020 and 2021 compared to tertiary education graduates. Additionally, the presence of a child under four years in the household gradually reduced the probability of working during 2020, and married women had the lowest probability of working during the first quarter of 2020. This research sheds light on the gender-specific impacts of the pandemic on the labor market in Armenia and provides insights for future policy considerations.Pandemie Covid-19 měla významný dopad na trh práce žen v Arménii. Tato studie využívá data z průzkumů pracovní sily z let 2019, 2020 a 2021 ke zkoumání pravděpodobnosti žen pracovat během pandemie Covid-19, která začala v březnu 2020. Pomoci lineárního pravděpodobnostního modelu (LPM) zjišťuji, že ženy ve věku 30-39 let s odborným vzděláním měly v letech 2020 a 2021 nižší pravděpodobnost, že budou pracovat ve vybraných čtvrtletích ve srovnání s absolventkami terciárního vzdělání. Kromě toho, přítomnost dítěte do čtyř let v roce 2020 postupně snižovala pravděpodobnost pracovat, a vdané ženy měly nejnižší pravděpodobnost, že budou pracovat během prvního čtvrtletí roku 2020. Tento výzkum vnáší světlo na genderově specifické dopady pandemie na trh práce v Arménii a popisuje mechanismus, který může být užitečný pro budoucí politická rozhodnutí.CERGEFaculty of Social SciencesFakulta sociálních vě

Women's employment before and during the Covid-19 pandemic: The case of Armenia

The Covid-19 pandemic had a significant impact on female labor market outcomes in Armenia. This study uses Armenian Labor Force Surveys data from 2019, 2020, and 2021 to examine women's probability of working in the labor market during the Covid-19 pandemic that started in March 2020. Employing the linear probability model (LPM) approach, I find that 30-39 years old women with vocational education had a lower probability of working during specific quarters in 2020 and 2021 compared to tertiary education graduates. Additionally, the presence of a child under four years in the household gradually reduced the probability of working during 2020, and married women had the lowest probability of working during the first quarter of 2020. This research sheds light on the gender-specific impacts of the pandemic on the labor market in Armenia and provides insights for future policy considerations