A5037170348- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Galaxies: Formation, Evolution, Phenomena
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Adaptive optics and wavefront sensing
- Plant Toxicity and Pharmacological Properties
- Calibration and Measurement Techniques
- Scientific Research and Discoveries
- Astrophysical Phenomena and Observations
- Plant Reproductive Biology
- Agricultural safety and regulations
- Molecular Spectroscopy and Structure
- Scientific Measurement and Uncertainty Evaluation
- Statistical and numerical algorithms
- High-pressure geophysics and materials
- History and Developments in Astronomy
- Veterinary Equine Medical Research
- Botanical Research and Chemistry
- Photosynthetic Processes and Mechanisms
- Pharmacological Effects of Medicinal Plants
- Astronomical and nuclear sciences
- Historical Astronomy and Related Studies
Polish Academy of Sciences
2016-2024
Nicolaus Copernicus Astronomical Center
2016-2024
University of Warsaw
2014-2015
The extragalactic distance scale builds on the Cepheid period-luminosity (PL) relation. In this paper, we want to carry out a strictly differential comparison of absolute PL relations obeyed by classical Cepheids in Milky Way (MW), LMC and SMC galaxies. Taking advantage substantial metallicity difference among populations these three galaxies, establish possible systematic trend relation zero point as function metallicity, determine size such an effect optical near-infrared photometric...
Using a sample of 81 galactic, detached eclipsing binary stars we investigated the global zero-point shift their parallaxes with Gaia Data Release 2 (DR2) parallaxes. The in lay distance range 0.04-2 kpc from Sun. photometric {\pi}_Phot binaries were determined by applying number empirical surface brightness - color (SBC) relations calibrated on optical-infrared colors. For each SBC relation calculated individual differences d{\pi}_i = ({\pi}_Gaia {\pi}_Phot)_i and then unweighted weighted...
We present the results of a study type II Cepheid ($P_{puls} = 4.974 d$) in eclipsing binary system OGLE-LMC-T2CEP-098 ($P_{orb} 397.2 d$). The belongs to peculiar W Vir group, for which evolutionary status is virtually unknown. It first single-lined with pulsating component analyzed using method developed by Pilecki et al. (2013). show that presence pulsator makes it possible derive accurate physical parameters stars even if radial velocities can be measured only one components. have used...
Type II Cepheids (T2Ceps), alongside RR Lyrae stars, serve as important distance indicators for old Population stars due to their period--luminosity (PL) relations. However, few studies of these relations in the Sloan photometric system have been conducted. Our goal is calibrate PL (and counterparts Wesenheit magnitudes) Sloan--Pan-STARRS g_ P1 r_ i_ bands Galactic T2Ceps located vicinity Sun. We collected data $16$ BL Her type and $17$ W Vir using $40$ cm telescopes Las Cumbres Observatory...
Based on new observations and improved modeling techniques, we have reanalyzed seven Cepheids in the Large Magellanic Cloud. Improved physical parameters been determined for exotic system OGLE LMC-CEP-1718 composed of two first-overtone a completely model was obtained LMC-CEP-1812 classical Cepheid. This is now shortest period Cepheid which projection factor measured. The typical accuracy our dynamical masses radii determinations 1%. six follow period--radius relations literature. Our very...
The circumstellar envelopes (CSE) of Cepheids are still only poorly characterized despite their potential impact on the distance determination via both period-luminosity relation and parallax-of-pulsation method. This paper aims to investigate Galactic across instability strip in mid-infrared with MATISSE/VLTI order constrain geometry physical nature (gas and/or dust) CSEs. We secured observations eight short- up long-period pulsations L, M, N bands. For each star, we calibrated flux...
Aims . Surface brightness-colour relations (SBCRs) are useful tools for predicting the angular diameters of stars. They offer possibility to calculate precise spectrophotometric distances based on eclipsing binary method or Baade–Wesselink method. Double-lined detached stars (SB2 DEBs), with precisely known trigonometric parallaxes, allow us calibrate SBCRs a high level precision. To improve such calibrations, it is important supplement sample suitable binaries determined physical...
We report the discovery and characterisation of a deeply eclipsing AM CVn-system, Gaia14aae (= ASSASN-14cn). was identified independently by All-Sky Automated Survey for Supernovae (ASAS-SN; Shappee et al. 2014) Gaia Science Alerts project, during two separate outbursts. A third outburst is seen in archival Pan-STARRS-1 (PS1; Schlafly 2012; Tonry Magnier 2013) ASAS-SN data. Spectroscopy reveals hot, hydrogen-deficient spectrum with clear double-peaked emission lines, consistent an accreting...
Abstract We present a determination of the precise fundamental physical parameters 20 detached, double-lined, eclipsing binary stars in Large Magellanic Cloud (LMC) containing G- or early K-type giant stars. Eleven are new systems; remaining nine systems already analyzed by our team for which we updated parameters. The catalog results from long-term survey binaries Clouds suitable high-precision distances (the Araucaria Project). V -band brightnesses range 15.4 to 17.7 mag, and their orbital...
We study 147 star clusters in the Large Magellanic Cloud (LMC) order to determine their mean metallicities and ages, as well of 80 surrounding fields. construct an age-metallicity relation (AMR) for LMC. For this purpose, we used Str\"omgren photometry obtained with SOI camera on 4.1 m SOAR telescope. found metallicity age 110 clusters. remaining 37, provide estimation only. To best our knowledge, 29 from sample, both first time, whereas 66 clusters, a determination metallicity, 43 age. also...
The Baade-Wesselink (BW) method of distance determination Cepheids is used to calibrate the scale. Various versions this are mainly based on interferometry and/or surface-brightness color relation (SBCR). We quantify impact SBCR, its slope, and zeropoint projection factor. This quantity convert pulsation velocity into radial in BW method. also study extinction a potential circumstellar environment analyzed HARPS-N spectra eta Aql derive curve using different methods. then applied inverse...
Abstract Using high-quality observed period–luminosity ( P – L ) relations in both Magellanic Clouds the VIJHK s bands and optical near-infrared Wesenheit indices, we determine effect of metallicity on Cepheid by comparing relative distance between LMC SMC as determined from Cepheids to difference that has been derived with very high accuracy late-type eclipsing binary systems. Within an uncertainty 3%, which is dominated mean populations SMC, find effects smaller than 2% all consistent a...
Abstract We present a new study of late-type eclipsing binary stars in the Small Magellanic Cloud (SMC) undertaken with aim improving distance determination to this important galaxy. A sample 10 detached, double-lined binaries identified from OGLE variable star catalogs and consisting F- G-type giant components has been analyzed. The absolute physical parameters individual have measured typical accuracy better than 3%. All but one systems consist young intermediate population masses range...
Aims. In this work we study 35 stellar clusters in the Small Magellanic Cloud (SMC) order to provide their mean metallicities and ages. We also of fields surrounding clusters. Methods. used Strömgren photometry obtained with 4.1 m SOAR telescope take advantage ( b − y ) 1 colors for which there is a metallicity calibration presented literature. Results. The spatial age distributions across SMC are investigated using results by photometry. confirm earlier observations that younger, more...
Abstract Our work presents an independent calibration of the J -region Asymptotic Giant Branch (JAGB) method using Infrared Survey Facility photometric data and a custom luminosity function profile to determine JAGB mean magnitudes for nine galaxies. We absolute magnitude carbon stars M LMC = −6.212 ± 0.010 (stat.) ±0.030 (syst.) mag. then use near-infrared photometry number nearby galaxies, originally obtained by our group their distances from Cepheids Leavitt law, in order independently...
Context . The application of the parallax-of-pulsation (PoP) technique to determine distances pulsating stars implies use a scaling parameter, namely projection factor ( p -factor), which is required transform disc-integrated radial velocities (RVs) into photospheric expansion velocities. value this parameter poorly known and still debated. Most present applications PoP assume constant -factor. However, it may actually depend on physical parameters each star, as past studies designed...
Context. Binary Cepheids with giant companions are crucial for studying the physical properties of Cepheid variables, in particular providing best means to measure their masses. Systems composed two even more important, but date, only one such system has been identified, Large Magellanic Cloud (LMC). Aims. Our current aim is increase number these systems known tenfold and provide basic characteristics. The final goal obtain component Cepheids, including masses radii, learn about evolution...
We have analyzed the double-lined eclipsing binary system ASAS J180057-2333.8 from All Sky Automated Survey (ASAS) catalogue . measure absolute physical and orbital parameters for this based on archival $V$-band $I$-band photometry, as well high-resolution spectroscopic data obtained with ESO 3.6m/HARPS CORALIE spectrographs. The of were derived an accuracy about 0.5 - 3%. is a very rare configuration two bright well-detached giants spectral types K1 K4 luminosity class II. radii stars are...
We obtained single-phase near-infrared (NIR) magnitudes in the $J$- and $K$-band for a sample of 33 RR Lyrae stars Carina dSph galaxy. Applying different theoretical empirical calibrations NIR period-luminosity-metallicity relation stars, we find consistent results obtain true, reddening-corrected distance modulus 20.118 $\pm$ 0.017 (statistical) 0.11 (systematic) mag. This value is excellent agreement with context Araucaria Project from photometry Red Clump (20.165 0.015) Tip Giant Branch...
Abstract We present time-series photometry of 21 nearby type II Cepheids in the near-infrared J , H and K s passbands. use this photometry, together with Third Gaia Early Data Release parallaxes, to determine for first time period–luminosity relations (PLRs) from field representatives these old pulsating stars regime. found PLRs be very narrow BL Herculis stars, which makes them candidates precision distance indicators. then archival most accurate obtained eclipsing binaries recalibrate...
Abstract We present new period–luminosity and period–luminosity–metallicity relations for Galactic RR Lyrae stars based on a sample of 28 pulsators located at distances up to 1.5 kpc from the Sun. Near-infrared photometry was obtained Cerro Armazones Observatory, parallaxes were taken Gaia Early Data Release 3. Relations determined 2MASS JHK s bands W JK Wesenheit index. compare our results with other calibrations available in literature obtain very good agreement Lyraes Large Magellanic...
Abstract Following the earlier discovery of classical Cepheid variables in Sculptor Group spiral galaxy NGC 7793 from an optical wide-field imaging survey, we have performed deep near-infrared J - and K -band follow-up photometry a subsample these Cepheids to derive distance this with higher accuracy than what was possible alone, by minimizing effects reddening metallicity on result. Combining our new period–luminosity relations previous photometry, obtain true modulus (27.66 ± 0.04) mag...
Abstract We present reddening maps of the Large Magellanic Cloud (LMC) and Small (SMC), based on color measurements red clump. Reddening values our were obtained by calculating difference observed intrinsic clump in both galaxies. To obtain clump, we used reddenings from late-type eclipsing binary systems, for blue supergiants derived Strömgren photometry B-type stars. ( V − I ) 0 = 0.838 ± 0.034 mag LMC, 0.814 SMC. prepared map with 3′ resolution, covering central part LMC The mean value is...
Aims. In the course of a project to study eclipsing binary stars in vinicity Sun, we found that cooler component LL Aqr is solar twin candidate. This first known star with properties existing non-interacting binary, offering an excellent opportunity fully characterise its physical very high precision.