Mapping the Northern Galactic Disk Warp with Classical Cepheids

We present an updated three dimensional map of the Milky Way based on a sample of 2431 classical Cepheid variable stars, supplemented with about 200 newly detected classical Cepheids from the OGLE survey. The new objects were discovered as a result of a dedicated observing campaign of the ≈280 square degree extension of the OGLE footprint of the Galactic disk during 2018-2019 observing seasons. These regions cover the main part of the northern Galactic warp that has been deficient in Cepheids so far. We use direct distances to the sample of over 2390 classical Cepheids to model the distribution of the young stellar population in the Milky Way and recalculate the parameters of the Galactic disk warp. Our data show that its northern part is very prominent and its amplitude is ≈10% larger than that of the southern part. By combining Gaia astrometric data with the Galactic rotation curve and distances to Cepheids from our sample, we construct a map of the vertical component of the velocity vector for all Cepheids in the Milky Way disk. We find large-scale vertical motions with amplitudes of 10-20 km/s, such that Cepheids located in the northern warp exhibit large positive vertical velocity (toward the north Galactic pole), whereas those in the southern warp - negative vertical velocity (toward the south Galactic pole)

Over 78 000 RR Lyrae Stars in the Galactic Bulge and Disk from the OGLE Survey

We present an upgrade of the OGLE Collection of RR Lyrae stars in the Galactic bulge and disk. The size of our sample has been doubled and reached 78 350 RR Lyr variables, of which 56 508 are fundamental-mode pulsators (RRab stars), 21 321 pulsate solely in the first-overtone (RRc stars), 458 are classical double-mode pulsators (RRd stars), and 63 are anomalous RRd variables (including six triple-mode pulsators). For all the newly identified RR Lyr stars, we publish time-series photometry obtained during the OGLE Galaxy Variability Survey. We present the spatial distribution of RR Lyr stars on the sky, provide a list of globular clusters hosting RR Lyr variables, and discuss the Petersen diagram for multimode pulsators. We find new RRd stars belonging to a compact group in the Petersen diagram (with period ratios P₁₀/P_F ≈ 0.74 and fundamental-mode periods P_F ≈ 0.44 d) and we show that their spatial distribution is roughly spherically symmetrical around the Milky Way center

Wine of Cool-climate Areas in South Poland

A number of new vinery production regions, especially in the southern parts of Poland, have appearedin the last ten-odd years. This study was aimed at completing the chemical characterisation of wineproduced from ten Polish grape cultivars planted near Krakow. The wine was analysed to determineorganic acid concentrations, total polyphenols and extract content, antioxidant activity, alcohol content,total acidity and pH. Moreover, a sensory analysis was performed on the wine. Significant differenceswere recorded between red and white wine. The total acidity expressed as tartaric acid, and tartaric andmalic acid concentrations, were significantly higher in white and red wines, whereas antioxidant activityand phenolic content were significantly higher in the red wines. Similarities and relationships betweenvarious parameters and specific wine brands were further examined with cluster analysis. Our resultsshow that, under Polish climatic conditions, it is possible to produce wine with quality comparable towine from established wine denomination regions. Selected wine brands showed high antioxidantactivity (FRAP – ferric reducing antioxidant power) and a high level of polyphenols. This study alsoprovides confirmation that wines from colder climates frequently reveal unique and desirable properties

Long photometric cycle and disk evolution in the β\beta Lyrae type binary OGLE-BLG-ECL-157529

The subtype of hot algol semidetached binaries dubbed Double Periodic Variables (DPVs) are characterized by a photometric cycle longer than the orbital one, whose nature has been related to a magnetic dynamo in the donor component controlling the mass transfer rate. We aim to understand the morphologic changes observed in the light curve of OGLE-BLG-ECL-157529 that are linked to the long cycle. In particular, we want to explain the changes in relative depth of primary and secondary eclipses. We analyze $I$ and $V$-band OGLE photometric times series spanning 18.5 years and model the orbital light curve. We find that OGLE-BLG-ECL-157529 is a new eclipsing Galactic DPV of orbital period 24\fd8, and that its long cycle length decreases in amplitude and length during the time baseline. We show that the changes of the orbital light curve can be reproduced considering an accretion disk of variable thickness and radius, surrounding the hottest stellar component. Our models indicate changes in the temperatures of hot spot and bright spot during the long cycle, and also in the position of the bright spot. This, along with the changes in disk radius might indicate a variable mass transfer in this system.Comment: 8 pages, 14 figures, 2 tables, accepted for publication in Astronomy and Astrophysic