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{We present the radial metallicity gradients within the Galactic thin disc population through main-sequence stars selected on the chemical plane using GALAH DR3 accompanied with Gaia DR3 astrometric data. The [Fe/H], [$\alpha$/Fe] and [Mg/H] radial gradients are estimated for guiding radius as $-0.074\pm 0.006$, $+0.004\pm0.002$, $-0.074\pm0.006$ dex kpc$^{-1}$ and for the traceback early orbital radius as $-0.040\pm0.002$, $+0.003\pm 0.001$, $-0.039\pm 0.002$ dex kpc$^{-1}$ for 66,545 thin-disc stars, respectively. Alteration of the chemical structure within the Galactic disc caused by the radial orbital variations complicates results for the radial metallicity gradient. The effect of radial orbital variations on the metallicity gradients as a function on time indicates the following results: (i) The presence of a gradient along the disc throughout the time for which the model provides similar prediction, (ii) the radial orbital variations becomes more pronounced with the age of the stellar population and (iii) the effect of radial orbital variations on the metallicity gradients is minimal. The effect of radial orbital variations is found to be at most 6\% which does not statistically affect the radial gradient results. These findings contribute to a better understanding of the chemical evolution within the Galactic disc and provide an important basis for further research., Comment: 19 pages, including 15 figures & 1 table, accepted for publication in Astronomische Nachrichten. We would like to especially thank the editorial board for their contribution to the publication of the study

Determining the physical nature of a star requires precise knowledge of its stellar atmospheric parameters, including effective temperature, surface gravity, and metallicity. This study presents a new atomic line list covering a broad spectral range (1-2.5 $\mu$m; $YJHK$-bands) for iron (Fe) and $\alpha$-elements (Ca, Mg, Ti, Si) to improve stellar parameter determination using near-infrared (NIR) spectroscopy. We highlight the limitations of existing line lists, stemming primarily from inconsistencies in oscillator strengths for ionized iron lines within the APOGEE DR17. The line list was validated using the high-resolution and high-quality disc-center NIR spectra of the Sun and its solar analog HD 76151. As a result of the spectroscopic analyses, the effective temperature of HD 76151 was calculated as 5790$\pm$170 K, surface gravity as 4.35$\pm$0.18 cgs, metal abundance as 0.24$\pm$0.09 dex, and microturbulence velocity of 0.30$^{\rm +0.5}_{\rm -0.3}$ km s$^{-1}$ by combining the optical and NIR line lists. A comparison of the model atmospheric parameters calculated for HD 76151 with the PARSEC isochrones resulted in a stellar mass of $1.053_{-0.068}^{+0.056} M_{\odot}$, radius $1.125_{-0.011}^{+0.035} R_{\odot}$, and an age of 5.5$^{\rm +2.5}_{\rm -2.1}$ Gyr. For the first time, kinematic and dynamical orbital analyses of HD 76151 using a combination of Gaia astrometric and spectroscopic data showed that the star was born in a metal-rich region within the Solar circle and is a member of the thin disc population. Thus, the slightly metal-rich nature of the star, as reflected in its spectroscopic analysis, was confirmed by dynamical orbital analysis., Comment: 31 pages, including 8 figures and 13 tables, accepted for publication in the Astrophysical Journal

This study outlines a detailed investigation using CCD {\it UBV} and {\it Gaia} DR3 data sets of the two open clusters Ruprecht 1 (Rup-1) and Ruprecht 171 (Rup-171). Fundamental astrophysical parameters such as color excesses, photometric metallicities, ages, and isochrone distances were based on {\it UBV}-data analyses, whereas membership probability calculations, structural and astrophysical parameters, as well as the kinematic analyses were based on {\it Gaia} DR3-data. We identified 74 and 596 stars as the most probable cluster members with membership probabilities over 50\% for Rup-1 and Rup-171, respectively. The color excesses $E(B-V)$ were obtained as $0.166\pm0.022$ and $0.301\pm0.027$ mag for Rup-1 and Rup-171, respectively. Photometric metallicity analyses were performed by considering F-G type main-sequence member stars and found to be [Fe/H]=$-0.09\pm 0.16$ and [Fe/H]=$-0.20\pm 0.20$ dex for Rup-1 and Rup-171, respectively. Ages and distances were based on both {\it UBV} and {\it Gaia}-data analyses; according to isochrone-fitting these values were estimated to be $t=580\pm60$ Myr, $d=1469\pm57$ pc for Rup-1 and $t=2700\pm200$ Myr, $d=1509\pm69$ pc for Rup-171. The present-day mass function slope of Rup-1 was estimated as $1.26\pm0.32$ and Rup-171 as $1.53\pm1.49$. Galactic orbit integration analyses showed that both of the clusters might be formed outside the solar circle., Comment: 14 figures and 4 tables, article accepted for publication in Astronomische Nachrichten

In this study, spectral, age, kinematic, and orbital dynamical analyses were conducted on metal-poor and high proper-motion (HPM) stars, HD 8724 and HD 195633, selected from the Solar neighborhood. This analysis combines detailed abundance measurements, kinematics, and orbital dynamics to determine their origin. Standard 1D local thermodynamic equilibrium analysis provides a fresh determination of the atmospheric parameters: $T_{\rm eff}=$4700$\pm$115 K, $\log g=$ 1.65$\pm$0.32 cgs, [Fe/H]=-1.59$\pm$0.04 dex, and a microturbulent velocity $\xi=$ 1.58$\pm$0.50 km s$^{\rm -1}$ for HD 8724 and $T_{\rm eff}=$6100$\pm$205 K, $\log g=$3.95$\pm$0.35 cgs, [Fe/H]=-0.52$\pm$0.05 dex, and $\xi=$1.26$\pm$0.50 km s$^{\rm -1}$ for HD 195633. The ages were estimated using a Bayesian approach (12.25 Gyr for HD 8724 and 8.15 Gyr for HD 195633). The escape scenarios of these stars from 170 candidate globular clusters (GCs) in the Galaxy were also investigated because of their chemical and physical differences (HPM and metal-poor nature). Accordingly, the calculated probability of encounter ($59\%$) for HD 8724 at a distance of five tidal radius suggests that star HD 8724 may have escaped from NGC 5139 ($\omega$ Cen), supported by its highly flattened orbit and may belong to a sub-population of this GC. Conversely, HD 195633's kinematics, age, and metal abundances point towards an escape from the bulge GC NGC 6356., Comment: 19 pages, including 12 figures and 8 tables, accepted for publication in Astronomische Nachrichten

Eclipsing binary systems are significant objects for astrophysics in that direct observations can determine the fundamental parameters of stars. In this study, we determined precisely the fundamental parameters of the binary component stars obtained by simultaneous analysis of radial velocities and the {\it TESS} light curve using the Wilson and Devinney code. Following the analysis, the masses and radii of the primary and secondary components were determined as $M_{1}= 1.58\pm 0.01M_\odot$, $M_{2}= 0.48\pm0.02M_\odot$, and $R_{1}=1.93\pm 0.01R_\odot$, $R_{2}= 1.14\pm 0.01 R_\odot$, respectively. Furthermore, the distance of IS CMa is calculated as $92.7\pm6.5$ pc. On the basis of the analysis of the mid-eclipse times, it was found that the variation in the orbital period is represented by an upward parabola. It has an increasing rate of $dP/dt$ = 1.09 $\times$ 10$^{-7}$ day yr$^{-1}$. Using PARSEC stellar evolutionary tracks and isochrones with solar metallicity were estimated the age of IS CMa as $1.3\pm0.1$ Gyr. Kinematic and Galactic orbital parameters of IS CMa were obtained from the astrometric and spectroscopic data of the system. The Galactic orbit analysis reveals that IS CMa formed inside the solar circle and it is a member of the young thin-disc population., Comment: 12 pages, including 6 figures and 4 tables, accepted for publication in Astronomische Nachrichten

The hyperfine structure of 40 spectral lines of singly ionized thulium (Tm II) in emission spectra from a hollow cathode discharge lamp measured with a Fourier transform spectrometer in the wavelength range from 335 nm to 2345 nm has been investigated. As a result of the analysis, the magnetic dipole hyperfine structure constants $A$ for 27 fine structure levels of Tm II were determined for the first time. In addition, the values of two magnetic dipole hyperfine structure constants $A$ from the literature were declared incorrect and the corrected values were given., Comment: 15 pages, 6 figures and 3 tables, accepted for publication in ApJ

Developments on various relations among stellar variables such as the main sequence empirical mass-luminosity (MLR), mass-radius (MRR) and mass-effective temperature (MTR) relations were reviewed. Conceptual changes in their understanding and usages were discussed. After its discovery, MLR was treated as one of the fundamental secrets of the cosmos. Differences between fundamental laws and statistical relations were used to understand long-term developments of MLR, MRR and MTR. Developments show a break point, initiated by Andersen et al. (1991), in the line of progress. Before the break when reliable data were limited, MLR and MRR were calibrated using M, L, and R of binary components of all kinds visual, spectroscopic, and eclipsing for two purposes: i) obtaining mean mass, mean luminosity, and mean radius, ii) to estimate M and R of single stars. By the time of the break, the number of solutions from detached double-lined eclipsing binaries (DDEB) giving accurate M and R within a few percent levels are increased. Parameters from very close, semi-detached, and contact binaries were excluded for refinement, however, MLR and MRR diagrams were found insufficient to derive MLR and MRR functions because the dispersions are not only due to random observational errors but also due to chemical composition and age differences. Then, a new trend was adopted by replacing classical MLR and MRR with empirical M and R predicting relations. Thus, the purpose one was suppressed also because the new trend found a fruitful application in determining M and R of exoplanet hosting single stars. Corrections on misnames and devising new classical MLR, MRR, and MTR, giving mean values are encouraged since they are still useful and needed by astrophysical models requiring such mean values, not only beneficial to astrophysics, but also beneficial to Galactic, extragalactic search, even cosmological models., Comment: 26 pages, 7 figures and 2 tables, accepted for publication in Physics and Astronomy Reports

A detailed analysis of ground-based CCD UBV photometry and space-based Gaia Data Release 3 (DR3) data for the open clusters King 6 and NGC 1605 was performed. Using the pyUPMASK algorithm on Gaia astrometric data to estimate cluster membership probabilities, we have identified 112 stars in King 6 and 160 stars in NGC 1605 as the statistically most likely members of each cluster. We calculated reddening and metallicity separately using UBV two-color diagrams to estimate parameter values via independent methods. The color excess $E(B-V)$ and photometric metallicity [Fe/H] for King 6 are $0.515 \pm 0.030$ mag and $0.02 \pm 0.20$ dex, respectively. For NGC 1605, they are $0.840 \pm 0.054$ mag and $0.01 \pm 0.20$ dex. With reddening and metallicity kept constant, we have estimated the distances and cluster ages by fitting PARSEC isochrones to color-magnitude diagrams based on the Gaia and UBV data. Photometric distances are 723 $\pm$ 34 pc for King 6 and 3054 $\pm$ 243 pc for NGC 1605. The cluster ages are $200 \pm 20$ Myr and $400 \pm 50$ Myr for King 6 and NGC 1605, respectively. Mass function slopes were found to be 1.29 $\pm$ 0.18 and 1.63 $\pm$ 0.36 for King 6 and NGC 1605, respectively. These values are in good agreement with the value of Salpeter (1955). The relaxation times were estimated as 5.8 Myr for King 6 and 60 Myr for NGC 1605. This indicates that both clusters are dynamically relaxed since these times are less than the estimated cluster ages. Galactic orbit analysis shows that both clusters formed outside the solar circle and are members of the young thin-disc population., Comment: 25 pages, including 14 figures and 7 tables, accepted for publication in the Astronomical Journal

We propose a line list that may be useful for the abundance analysis of G-type stars in the wavelength range 4080 -- 6780 A. It is expected that the line list will be useful for surveys/libraries with overlapping spectral regions (e.g. ELODIE/SOPHIE libraries, UVES-580 setting of Gaia-ESO), and in particular for the analysis of F- and G-type stars in general. The atomic data are supplemented by detailed references to the sources. We estimated the Solar abundances using stellar lines and the high-resolution Kitt Peak National Observatory (KPNO) spectra of the Sun to determine the uncertainty in the log gf values. By undertaking a systematic search that makes use of the lower excitation potential and gf-values and using revised multiplet table as an initial guide, we identified 363 lines of 24 species that have accurate gf-values and are free of blends in the spectra of the Sun and a Solar analogue star, HD 218209 (G6V), for which accurate and up-to-date abundances were obtained from both ELODIE and PolarBASE spectra of the star. For the common lines with the Gaia-ESO line list v.6 provided by the Gaia-ESO collaboration, we discovered significant inconsistencies in the gf-values for certain lines of varying species., Comment: 17 pages, 4 figures and 5 tables, accepted for publication in Physics and Astronomy Reports

We perform extensive spectroscopy of the supernova remnant N63A in the Large Magellanic Cloud, using $\sim 43$ ks {\it Chandra} archival data. By analysing the spectra of the entire remnant, we determine the abundance distributions for O, Ne, Mg, Si, and Fe. We detect evidence of enhanced O and possibly Ne and Mg in some of the central regions which might indicate an asymmetric distribution of the ejecta. The average O/Ne, O/Mg, and Ne/Mg abundance ratios of the ejecta are in plausible agreement with the nucleosynthesis products from the explosion of a $\sim40$ $M_{\odot}$ progenitor. We estimate an upper limit on the Sedov age of $\sim 5,400\pm200$ yr and explosion energy of $\sim 8.9\pm 1.6\times 10^{51}$ erg for N63A. We discuss the implications of our results for the morphological structure of the remnant, its circumstellar medium and the nature of the progenitor star., Comment: 22 pages, including 9 figures and 4 tables, accepted for publication in Monthly Notices of the Royal Astronomical Society. arXiv admin note: substantial text overlap with arXiv:2201.09891

This paper presents photometric, astrometric, and kinematic analyses of the open clusters NGC 189, NGC 1758 and NGC 7762 based on CCD UBV photometric and Gaia Data Release 3 (DR3) data. According to membership analyses, we identified 32, 57 and 106 most probable member stars with membership probabilities $P\geq 0.5$ in NGC 189, NGC 1758 and NGC 7762, respectively. The color excesses and photometric metallicities of each cluster were determined separately using UBV two-color diagrams. The color excess $E(B-V)$ is $0.590 \pm 0.023$ mag for NGC 189, $0.310 \pm 0.022$ mag for NGC 1758 and $0.640 \pm 0.017$ mag for NGC 7762. The photometric metallicity [Fe/H] is $-0.08 \pm 0.03$ dex for both NGC 189 and NGC 1758, and $-0.12 \pm 0.02$ dex for NGC 7762. Distance moduli and ages of the clusters were obtained by comparing PARSEC isochrones with the color-magnitude diagrams constructed from UBV and Gaia photometric data. During this process, we kept as constant color excess and metallicity for each cluster. The estimated isochrone distance is $1201 \pm 53$ pc for NGC 189, $902 \pm 33$ pc for NGC 1758 and $911 \pm 31$ pc for NGC 7762. These are compatible with the values obtained from trigonometric parallax. Ages of the clusters are $500\pm 50$ Myr, $650\pm 50$ Myr and $2000\pm 200$ Myr for NGC 189, NGC 1758 and NGC 7762, respectively. Galactic orbit integration of the clusters showed that NGC 1758 completely orbits outside the solar circle, while NGC 189 and NGC 7762 enter the solar circle during their orbits., Comment: 25 pages, 11 figures and 6 tables, accepted for publication in Advances in Space Research

The spatial distribution, Galactic model parameters and luminosity function of cataclysmic variables (CVs) are established using re-estimated trigonometric parallaxes of {\it Gaia} DR3. The data sample of 1,587 CVs in this study is claimed to be suitable for Galactic model parameter estimation as the distances are based on trigonometric parallaxes and the {\it Gaia} DR3 photometric completeness limits were taken into account when the sample was created. According to the analysis, the scale height of All CVs increases from 248$\pm$2 to 430$\pm$4 pc towards shorter periods near the lower limit of the period gap and suddenly drops to 300$\pm$2 pc for the shortest orbital period CVs. The exponential scale heights of All CVs and magnetic systems are found to be 375$\pm$2 and 281$\pm$3 pc, respectively, considerably larger than those suggested in previous observational studies. The local space density of All CVs and magnetic systems in the sample are $6.8^{+1.3}_{-1.1}\times$10$^{-6}$ and $2.1^{+0.5}_{-0.4}\times10^{-6}$ pc$^{-3}$, respectively. Our measurements strengthen the 1-2 order of magnitude discrepancy between CV space densities predicted by population synthesis models and observations. It is likely that this discrepancy is due to objects undetected by CV surveys, such as the systems with very low $\dot{M}$ and the ones in the period gap. The comparisons of the luminosity function of white dwarfs with the luminosity function of All CVs in this study show that 500 times the luminosity function of CVs fits very well to the luminosity function of white dwarfs. We conclude that the estimations and data sample in this study can be confidently used in further analysis of CVs., Comment: 23 pages, including 12 figures and 6 tables, accepted for publication in the Astronomical Journal

Arbitrariness in the zero point of bolometric corrections is a nearly century-old paradigm leading to two more paradigms. "Bolometric corrections must always be negative," and "bolometric magnitude of a star ought to be brighter than its $V$ magnitude". Both were considered valid before IAU 2015 General Assembly Resolution B2, a revolutionary document that supersedes all three aforementioned paradigms. The purpose of this article is to initiate a new insight and a new understanding of the fundamental astrophysics and present new capabilities to obtain standard and more accurate stellar luminosities and gain more from accurate observations in the era after Gaia. The accuracy gained will aid in advancing stellar structure and evolution theories, and also Galactic and extragalactic research, observational cosmology and dark matter and dark energy searches., Comment: 8 pages, including 1 figure, accepted for publication in the Astronomical Journal

We present photometric, astrometric, and kinematic studies of the old open star clusters NGC 1193 and NGC 1798. Both of the clusters are investigated by combining data sets from Gaia EDR3 and CCD UBV observational data. Analysis of the radial distribution of stars through the cluster regions indicates that the cluster limit radii are $r_{\rm lim}=8'$ for both of the clusters. We determine the membership probabilities of stars considering Gaia EDR3 proper motion and trigonometric parallax data, resulting in 361 stars in NGC 1193 and 428 in NGC 1798 being identified as most likely cluster members, having membership probabilities greater than P>0.5. Mean proper motion components are estimated as ($\mu_{\alpha}\cos \delta$, $\mu_{\delta}) = (-0.207(0.009), -0.431(0.008)$) for NGC 1193 and ($\mu_{\alpha}\cos \delta$, $\mu_{\delta})=(0.793(0.006), -0.373(0.005)$) mas/yr for NGC 1798. E(B-V) color excesses were derived for NGC 1193 as $0.150(0.037)$ and for NGC 1798 as 0.505(0.100) mag through the use of two-color diagrams. Photometric metallicities are also determined from two-color diagrams with the results of [Fe/H] = -0.30(0.06) dex for NGC 1193 and [Fe/H]=-0.20(0.07) dex for NGC 1798. The isochrone fitting distance and age of NGC 1193 are 5562(381) pc and 4.6(1) Gyr, respectively. For NGC 1798, these parameters are 4451(728) pc and 1.3(0.2) Gyr. These ages indicate that NGC 1193 and NGC 1798 are old open clusters. The overall present-day mass function slopes for main-sequence stars are found as 1.38(2.16) for NGC 1193 and 1.30(0.21) for NGC 1798, which are in fair agreement with the value of Salpeter (1955). Kinematic and dynamic orbital calculations indicate that NGC 1193 and NGC 1798 belong to the thick-disk and thin-disk populations, respectively. In addition, both of the clusters were born outside the solar circle, and both orbit in the metal-poor region of the Galactic disk., Comment: Comments: 29 pages, including 13 figures and 4 tables, accepted for publication in the Revista Mexicana de Astronom\'ia y Astrof\'isica