Retired A Stars and Their Companions: Exoplanets Orbiting Three Intermediate-Mass Subgiants

We report precision Doppler measurements of three intermediate-mass subgiants from Lick and Keck Observatories. All three stars show variability in their radial velocities consistent with planet-mass companions in Keplerian orbits. We find a planet with a minimum mass of 2.5 Mjup in a 351.5 day orbit around HD 192699, a planet with a minimum mass of 2.0 Mjup in a 341.1 day orbit around HD 210702, and a planet with a minimum mass of 0.61 Mjup in a 297.3 day orbit around HD 175541. Stellar mass estimates from evolutionary models indicate that all of these stars were formerly A-type dwarfs with masses ranging from 1.65 to 1.85 Msun. These three long-period planets would not have been detectable during their stars' main-sequence phases due to the large rotational velocities and stellar jitter exhibited by early-type dwarfs. There are now 9 "retired" (evolved) A-type stars (Mstar > 1.6 Msun) with known planets. All 9 planets orbit at distances a \geq 0.78 AU, which is significantly different than the semimajor axis distribution of planets around lower-mass stars. We examine the possibility that the observed lack of close-in planets is due to engulfment by their expanding host stars, but we find that this explanation is inadequate given the relatively small stellar radii of K giants (Rstar < 32 Rsun = 0.15 AU) and subgiants (Rstar < 7 Rsun = 0.03 AU). Instead, we conclude that planets around intermediate-mass stars reside preferentially beyond ~0.8 AU, which may be a reflection of different formation and migration histories of planets around A-type stars.Comment: 31 pages, 9 figures, 6 tables, ApJ accepted, corrected minor typo

Two Jovian planets around the giant star HD202696. A growing population of packed massive planetary pairs around massive stars?

We present evidence for a new two-planet system around the giant star HD202696 (= HIP105056, BD+26 4118). The discovery is based on public HIRES radial velocity measurements taken at Keck Observatory between July 2007 and September 2014. We estimate a stellar mass of 1.91$^{+0.09}_{-0.14}M_\odot$ for HD202696, which is located close to the base of the red giant branch. A two-planet self-consistent dynamical modeling MCMC scheme of the radial velocity data followed by a long-term stability test suggests planetary orbital periods of $P_{\rm b}$ = 517.8$_{-3.9}^{+8.9}$ days and $P_{\rm c}$ = 946.6$_{-20.9}^{+20.7}$ days, eccentricities of $e_{\rm b}$ = 0.011$_{-0.011}^{+0.078}$ and $e_{\rm c}$ = 0.028$_{-0.012}^{+0.065}$ , and minimum dynamical masses of $m_{\rm b}$ = 2.00$_{-0.10}^{+0.22}$\,$M_{\mathrm{Jup}}$ and $m_{\rm c}$ = 1.86$_{-0.23}^{+0.18}$,$M_{\mathrm{Jup}}$, respectively. Our stable MCMC samples are consistent with orbital configurations predominantly in a mean period ratio of 11:6 and its close-by high order mean-motion commensurabilities with low eccentricities. For the majority of the stable configurations we find an aligned or anti-aligned apsidal libration (i.e.\ $\Delta\omega$ librating around 0$^\circ$ or 180$^\circ$), suggesting that the HD202696 system is likely dominated by secular perturbations near the high-order 11:6 mean-motion resonance. The HD202696 system is yet another Jovian mass pair around an intermediate mass star with a period ratio below the 2:1 mean motion resonance. Therefore, the HD202696 system is an important discovery, which may shed light on the primordial disk-planet properties needed for giant planets to break the strong 2:1 mean motion resonance and settle in more compact orbits.Comment: Accepted for publication in AJ on 18th December 2018. 15 pages, 11 Figures, 4 Tables (this .v2 is copy corrected and identical with the published paper

Abiotic and Biotic Soil Characteristics in Old Growth Forests and Thinned or Unthinned Mature Stands in Three Regions of Oregon

We compared forest floor depth, soil organic matter, soil moisture, anaerobic mineralizable nitrogen (a measure of microbial biomass), denitrification potential, and soil/litter arthropod communities among old growth, unthinned mature stands, and thinned mature stands at nine sites (each with all three stand types) distributed among three regions of Oregon. Mineral soil measurements were restricted to the top 10 cm. Data were analyzed with both multivariate and univariate analyses of variance. Multivariate analyses were conducted with and without soil mesofauna or forest floor mesofauna, as data for those taxa were not collected on some sites. In multivariate analysis with soil mesofauna, the model giving the strongest separation among stand types (P = 0.019) included abundance and richness of soil mesofauna and anaerobic mineralizable nitrogen. The best model with forest floor mesofauna (P = 0.010) included anaerobic mineralizable nitrogen, soil moisture content, and richness of forest floor mesofauna. Old growth had the highest mean values for all variables, and in both models differed significantly from mature stands, while the latter did not differ. Old growth also averaged higher percent soil organic matter, and analysis including that variable was significant but not as strong as without it. Results of the multivariate analyses were mostly supported by univariate analyses, but there were some differences. In univariate analysis, the difference in percent soil organic matter between old growth and thinned mature was due to a single site in which the old growth had exceptionally high soil organic matter; without that site, percent soil organic matter did not differ between old growth and thinned mature, and a multivariate model containing soil organic matter was not statistically significant. In univariate analyses soil mesofauna had to be compared nonparametrically (because of heavy left-tails) and differed only in the Siskiyou Mountains, where they were most abundant and species rich in old growth forests. Species richness of mineral soil mesofauna correlated significantly (+) with percent soil organic matter and soil moisture, while richness of forest floor mesofauna correlated (+) with depth of the forest floor. Composition of forest floor and soil mesofauna suggest the two groups represent a single community. Soil moisture correlated highly with percent soil organic matter, with no evidence for drying in sites that were sampled relatively late in the summer drought, suggesting losses of surface soil moisture were at least partially replaced by hydraulic lift (which has been demonstrated in other forests of the region)

Автоматизация процесса ранжирования ис-полнителей на базе системы электронного документооборота DIRECTUM

Цель работы – автоматизация процессов рассмотрения заявок внешних исполнителей и согласования оценок работ подрядчиков по объектам путем разработки веб-приложения для подачи заявок субподрядчиков, прикладного решения в системе электронного документооборота DIRECTUM. В результате исследования разработано веб-приложение для подачи заявок в среде Microsoft Visual Studio, реализован дополнительный функционал в системе электронного документооборота DIRECTUM и создана интеграция веб-приложения с прикладным решением.The object of study consists of business processes for the review of subcontractor’s application and work estimation. The main goal of the research is to automatize business processes and to develop web application for subcontractors, application solution in EDMS DIRECTUM and their integration

Dose-dependent long-term effects of a single radiation event on behaviour and glial cells

Purpose The increasing use of low-dose ionizing radiation in medicine requires a systematic study of its long-term effects on the brain, behaviour and its possible association with neurodegenerative disease vulnerability. Therefore, we analysed the long-term effects of a single low-dose irradiation exposure at 10 weeks of age compared to medium and higher doses on locomotor, emotion-related and sensorimotor behaviour in mice as well as on hippocampal glial cell populations. Materials and methods We determined the influence of radiation dose (0, 0.063, 0.125 or 0.5 Gy), time post-irradiation (4, 12 and 18 months p.i.), sex and genotype (wild type versus mice with Ercc2 DNA repair gene point mutation) on behaviour. Results The high dose (0.5 Gy) had early-onset adverse effects at 4 months p.i. on sensorimotor recruitment and late-onset negative locomotor effects at 12 and 18 months p.i. Notably, the low dose (0.063 Gy) produced no early effects but subtle late-onset (18 months) protective effects on sensorimotor recruitment and exploratory behaviour. Quantification and morphological characterization of the microglial and the astrocytic cells of the dentate gyrus 24 months p.i. indicated heightened immune activity after high dose irradiation (0.125 and 0.5 Gy) while conversely, low dose (0.063 Gy) induced more neuroprotective features. Conclusion This is one of the first studies demonstrating such long-term and late-onset effects on brain and behaviour after a single radiation event in adulthood

HD 91669b: A New Brown Dwarf Candidate from the McDonald Observatory Planet Search

We report the detection of a candidate brown dwarf orbiting the metal-rich K dwarf HD 91669, based on radial-velocity data from the McDonald Observatory Planet Search. HD 91669b is a substellar object in an eccentric orbit (e=0.45) at a separation of 1.2 AU. The minimum mass of 30.6 Jupiter masses places this object firmly within the brown dwarf desert for inclinations i>23 degrees. This is the second rare close-in brown dwarf candidate discovered by the McDonald planet search program.Comment: Accepted for publication in A

Konzept OER-Zertifizierung an österreichischen Hochschulen

Das Ergebnis der Arbeitsgruppe „Open Educational Resources“ ist ein Konzept zur OER-Zertifizierung an österreichischen Hochschulen. Dazu wird unterschieden in eine zweistufige Zertifizierung für Hochschullehrende und eine dreistufige Zertifizierung für Hochschulen. Der Umsetzungsvorschlag sieht dafür digitale Open Badges vor, die von einer zentralen Stelle bereits in der nächsten Leistungsvereinbarungsperiode (2019–2021) vergeben werden sollen