Astronomy & Astrophysics最新文献

{"title":"PolarCat: Catalog of polars, low-accretion rate polars, and candidate objects","authors":"Axel D. Schwope","doi":"10.1051/0004-6361/202554519","DOIUrl":"https://doi.org/10.1051/0004-6361/202554519","url":null,"abstract":"Polars and low-accretion rate polars (LARPs) are strongly magnetic cataclysmic variables. Mediated by the magnetic field of the white dwarf, their spin and binary orbit are (mostly) synchronized. They play an important role in our understanding of close binary evolution and the generation of strong magnetic fields in white dwarfs. Thanks to X-ray all-sky surveys, optical variability, and spectroscopic surveys, the number of polars and LARPs has grown from just a few in the 1980s to more than 200 today. Follow-up studies are facilitated by the systematic compilation of these systems presented here, which is also made available as an online resource. Yearly updates are planned, and community input is highly appreciated.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"17 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144219093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A neural network approach to determining photometric metallicities of M-type dwarf stars","authors":"C. Duque-Arribas, H. M. Tabernero, D. Montes, J. A. Caballero, E. Galceran","doi":"10.1051/0004-6361/202554722","DOIUrl":"https://doi.org/10.1051/0004-6361/202554722","url":null,"abstract":"<i>Context.<i/> M dwarfs are the most abundant stars in the Galaxy and serve as key targets for stellar and exoplanetary studies. It is particularly challenging to determine their metallicities because their spectra are complex. For this reason, several authors have focused on photometric estimates of the M-dwarf metallicity. Although artificial neural networks have been used in the framework of modern astrophysics, their application to a photometric metallicity estimate for M dwarfs remains unexplored.<i>Aims.<i/> We develop an accurate method for estimating the photometric metallicities of M dwarfs using artificial neural networks to address the limitations of traditional empirical approaches.<i>Methods.<i/> We trained a neural network on a dataset of M dwarfs with spectroscopically derived metallicities. We used eight absolute magnitudes in the visible and infrared from <i>Gaia<i/>, 2MASS, and WISE as input features. Batch normalization and dropout regularization stabilized the training and prevented overfitting. We applied the Monte Carlo dropout technique to obtain more robust predictions.<i>Results.<i/> The neural network demonstrated a strong performance in estimating photometric metallicities for M dwarfs in the range of −0.45 ≤ [Fe/H] ≤ +0.45 dex and for spectral types as late as M5.0 V. On the test sample, the predictions showed uncertainties down to 0.08 dex. This surpasses the accuracy of previous methods. We further validated our results using an additional sample of 46 M dwarfs in wide binary systems with FGK-type primary stars with well-defined metallicities and achieved an excellent predictive performance that surpassed the 0.1 dex error threshold.<i>Conclusions.<i/> This study introduces a machine-learning-based framework for estimating the photometric metallicities of M dwarfs and provides a scalable data-driven solution for analyzing large photometric surveys. The results outline the potential of artificial neural networks to enhance the determination of stellar parameters, and they offer promising prospects for future applications.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"68 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144211401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiple stellar populations in MOCCA globular cluster models: Transient spatial overconcentration of pristine red giant stars driven by strong dynamical encounters","authors":"M. Giersz, A. Askar, A. Hypki, J. Hong, G. Wiktorowicz, L. Hellström","doi":"10.1051/0004-6361/202554233","DOIUrl":"https://doi.org/10.1051/0004-6361/202554233","url":null,"abstract":"Recent findings show that, in some Milky Way globular clusters (GCs), pristine red giant branch (RGB) stars are more centrally concentrated than enriched ones. This contradicts most multiple-population formation scenarios, which predict that the enriched population (2P) should initially be more concentrated than the pristine population (1P). We analyzed a MOCCA GC model that exhibits a higher spatial concentration of 1P RGB stars than 2P RGB stars at 13 Gyr. The MOCCA models assume the asymptotic giant branch (AGB) scenario, in which 2P stars are initially more concentrated than 1P stars. Our results indicate that the observed spatial distributions of multiple populations, and possibly their kinematics, are significantly shaped by dynamical interactions. These interactions preferentially eject 2P RGB progenitors from the central regions, leading to a transient overconcentration of 1P RGB stars at late times. This effect is particularly relevant for GCs with present-day masses of a few 10<sup>5<sup/> M<sub>⊙<sub/>, which have retained only about 10–20% of their initial mass. Such clusters may appear dynamically young due to heating from a black hole subsystem, even if they have undergone significant mass loss and dynamical evolution. Additionally, the relatively small number of RGB stars in these clusters suggests that interpreting the spatial distributions of multiple populations solely from RGB stars may lead to biased conclusions about the overall distribution of 1P and 2P. The apparent overconcentration of the 1P relative to the 2P is likely a transient effect driven by the preferential removal of 2P RGB progenitors via strong dynamical encounters. MOCCA models of multiple stellar populations based on the AGB scenario may explain anomalous features observed in some Galactic GCs, such as NGC 3201 and NGC 6101.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"32 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144211514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of stellar model input in correcting the asteroseismic scaling relations","authors":"G. Valle, M. Dell’Omodarme, P. G. Prada Moroni, S. Degl’Innocenti","doi":"10.1051/0004-6361/202554089","DOIUrl":"https://doi.org/10.1051/0004-6361/202554089","url":null,"abstract":"<i>Aims.<i/> This study investigates the variability of the theoretical correction factor, <i>f<i/><sub>Δ<i>ν<i/><sub/>, used in red giant branch (RGB) scaling relations, arising from different assumptions in stellar model computations.<i>Methods.<i/> Adopting a commonly used framework, we focused on a 1.0 <i>M<i/><sub>⊙<sub/> star and systematically varied seven input parameters: the reference solar mixture, the initial helium abundance, the inclusion of microscopic diffusion and mass loss, the method for calculating atmospheric opacity, the mixing-length parameter, and the boundary conditions. Each parameter was tested using two distinct but physically plausible values to mimic possible choices of different evolutionary codes. For each resulting stellar model, we computed the oscillation frequencies along the RGB and derived the large frequency spacing, Δ<i>ν<i/><sub>0<sub/>. The correction factor <i>f<i/><sub>Δ<i>ν<i/><sub/> was then calculated by comparing the derived Δ<i>ν<i/><sub>0<sub/> with that predicted by the uncorrected scaling relations.<i>Results.<i/> We found substantial variability in <i>f<i/><sub>Δ<i>ν<i/><sub/> across the different models. The variation ranged from approximately 1.3% in the lower RGB to about 3% at log <i>g<i/> = 1.4. This level of variability is significant, as it corresponds to roughly half the values typically quoted in the literature and leads to a systematic change in derived masses from 5% to more than 10%. The most significant contribution to this variability came from the choice of atmospheric opacity calculation (approximately 1.2%), with a smaller contribution from the inclusion of microscopic diffusion (approximately 0.4%).<i>Conclusions.<i/> These results indicate that the choice of the reference stellar model has a non-negligible impact on the calculation of correction factors applied to RGB star scaling relations.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"8 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144211402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polarimetric insights into a potential binary supermassive black hole system in Mrk 231","authors":"J. Biedermann, F. Marin, T. Barnouin","doi":"10.1051/0004-6361/202553694","DOIUrl":"https://doi.org/10.1051/0004-6361/202553694","url":null,"abstract":"<i>Context.<i/> Markarian 231 (Mrk 231) is one of the brightest ultraluminous infrared galaxies (ULIRGs) known to date. It displays a unique optical-ultraviolet (optical-UV) spectrum, characterized by a strong and perplexing attenuation in the near-UV, associated with a sudden polarization peak.<i>Aims.<i/> The aim of this study is to clarify the puzzling nature of Mrk 231’s spectrum by examining the potential existence of a binary supermassive black hole (SMBH) system in its core. To this end, we combined photometric information used in prior studies, with archival polarimetric data to provide a more thorough approach to the quasar’s structure and emission mechanisms. In particular, we evaluated the binary SMBH model as a potential explanation for the near-UV cutoff, while exploring its polarization response, for this source, for the first time.<i>Methods.<i/> Building on previous spectro-photometric modeling, we investigated the hypothesis that the core of Mrk 231 may host a binary SMBH system. In this scenario, the accretion disk of the primary, more massive SMBH is responsible for the optical-UV spectrum. The disk of the secondary, less massive SMBH, would be expected to essentially emit in the far-UV. We applied this model to archival photometric and polarimetric data of Mrk 231 and tried to obtain the best fit possible. To support our findings, we performed radiative transfer calculations to determine the spatial disposition of each main component constituting Mrk 231.<i>Results.<i/> We find that a binary SMBH model can reproduce both the observed flux and polarization of Mrk 231 remarkably well. We infer that the core potentially hosts a binary SMBH system, with a primary SMBH of about 1.6 × 10<sup>8<sup/> <i>M<i/><sub>⊙<sub/> and a secondary of about 1.1 × 10<sup>7<sup/> <i>M<i/><sub>⊙<sub/>, separated by a semimajor axis of ∼146 AU. The secondary SMBH drives a degree of polarization of ∼3% between 0.1 and 0.2 μm, with a corresponding polarization position angle of about 134°, which is consistent with scattering within an accretion disk. The primary SMBH and the structure around it are responsible for a degree of polarization of ∼23% between 0.3 and 0.4 μm with a corresponding polarization position angle of about 96°, that is possibly attributed to scattering within the quasar’s wind. Finally, our model predicts the existence of a second peak in polarized flux in the far-ultraviolet, a telltale signature that could definitively prove the presence of a binary SMBH.<i>Conclusions.<i/> These results strongly support the hypothesis of a binary SMBH in Mrk 231 and emphasizes the need for new far-ultraviolet spectropolarimeters to clearly detect the existence of subparsec binary SMBHs in nearby quasars.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"16 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144211404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supermassive black hole mass measurement in the spiral galaxy NGC 4736 using JWST/NIRSpec stellar kinematics","authors":"Dieu D. Nguyen, Hai N. Ngo, Tinh Q. T. Le, Alister W. Graham, Roberto Soria, Igor V. Chilingarian, Niranjan Thatte, N. T. Phuong, Thiem Hoang, Miguel Pereira-Santaella, Mark Durre, Diep N. Pham, Le Ngoc Tram, Nguyen B. Ngoc, Ngân Lê","doi":"10.1051/0004-6361/202554672","DOIUrl":"https://doi.org/10.1051/0004-6361/202554672","url":null,"abstract":"We present accurate mass measurements of the central supermassive black hole (SMBH) in NGC 4736 (M 94). We used the “gold-standard” stellar absorption features (CO band heads) at ∼2.3 μm, as opposed to gas emission lines, to trace the dynamics in the nuclear region, easily resolving the SMBH’s sphere of influence. The analysis uses observations made with the integral field unit of the Near-Infrared Spectrograph (NIRSpec) on the <i>James Webb<i/> Space Telescope and a surface brightness profile derived from <i>Hubble<i/> Space Telescope archival images. We used Jeans anisotropic models within a Bayesian framework, and comprehensive Markov chain Monte Carlo optimization, to determine the best-fit black hole mass, orbital anisotropy, mass-to-light ratio, and nucleus kinematical inclination. We obtained a SMBH mass <i>M<i/><sub>BH<sub/> = (1.60 ± 0.16)×10<sup>7<sup/> M<sub>⊙<sub/> (1<i>σ<i/> random error), which is consistent with the <i>M<i/><sub>BH<sub/>–<i>σ<i/> and <i>M<i/><sub>BH<sub/>–<i>M<i/><sub>⋆<sub/> relations. This is the first dynamical measurement of a <i>M<i/><sub>BH<sub/> in NGC 4736 based on the stellar kinematics observed with NIRSpec. We thus settle a longstanding inconsistency between estimates based on nuclear emission-line tracers and the <i>M<i/><sub>BH<sub/>–<i>σ<i/> relation. Our analysis shows that NIRSpec can detect SMBHs with <i>M<i/><sub>BH, min<sub/> ≈ 5 × 10<sup>6<sup/> M<sub>⊙<sub/> in galaxies within 5 Mpc and <i>σ<i/> ≈ 100 km s<sup>−1<sup/>.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"14 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144211398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The mass-metallicity relation at z ≳ 3 down to M⋆≃ 104 M⊙","authors":"M. Bellazzini, T. Muraveva, A. Garofalo","doi":"10.1051/0004-6361/202554043","DOIUrl":"https://doi.org/10.1051/0004-6361/202554043","url":null,"abstract":"The mass-metallicity relation (MZR) is a fundamental scale law of galaxies. It is observed to evolve with redshift in unresolved galaxies up to <i>z<i/> > 6. However, observational constraints limits our view at such early epochs to galaxies with <i>M<i/><sub>⋆<sub/> ≳ 10<sup>7<sup/> <i>M<i/><sub>⊙<sub/>. On the other hand, in the local Universe the MZR can be traced down to the faintest end of the galaxy luminosity function (<i>M<i/><sub>⋆<sub/> ≃ 10<sup>2<sup/> <i>M<i/><sub>⊙<sub/>) but we have access only to its present-day realization. We propose to use RR Lyrae stars to get the mean metallicity of local dwarf galaxies at the early epoch in which these variable stars were formed (<i>z<i/> ≳ 3), opening a new window on the evolution of the MZR across cosmic times down to the lowest mass. We used available data for a sample of Milky Way satellites to show that the evolution of the MZR from the epoch of the formation of RR Lyrae to the present day can indeed be traced with this approach. Notably, the results are broadly compatible with those inferred from high-<i>z<i/> galaxies from nebular emission lines. The limitations of the approach as well as possible ways to refine the analysis are also briefly discussed.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"260 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144211400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying the detectability of Milky Way satellites with image simulations: Case study with KiDS","authors":"Shiyang Zhang, Hendrik Hildebrandt, Ziang Yan, Simon E. T. Smith, Massimiliano Gatto, Massimo Dall’Ora, Crescenzo Tortora, Shun-Sheng Li, Dominik Elsässer","doi":"10.1051/0004-6361/202554189","DOIUrl":"https://doi.org/10.1051/0004-6361/202554189","url":null,"abstract":"Ultra-faint dwarf galaxies, which can be detected as resolved satellite systems of the Milky Way, are critical to our understanding of galaxy formation, evolution, and the nature of dark matter, as they are the oldest, smallest, most metal-poor, and most dark matter-dominated stellar systems known thus far. Quantifying the sensitivity of surveys is essential to investigating their capability and limitations in searching for ultra-faint satellites. In this paper, we present the first study of the image-level observational selection function for Kilo-Degree Survey (KiDS) based on the Synthetic UniveRses For Surveys (SURFS) based on KiDS Legacy-like simulations. We generated mock satellites and simulated images that included resolved stellar populations of the mock satellites and the background galaxies, capturing realistic observational effects such as source blending, photometric uncertainties, and star-galaxy separation. We applied the matched-filter method to recover the injected satellites. We derived the observational selection function of the survey in terms of the luminosity, half-light radius, and heliocentric distance of the satellites. Compared to the catalogue-level simulation typically used in previous studies, the image-level simulation provides a more realistic assessment of survey sensitivity, accounting for observational limitations that are neglected in catalogue-level simulations. The image-level simulation shows a detection loss for compact sources with a distance <i>d<i/> ≳ 100 kpc. We argue that this is because compact sources are more likely to be identified as single sources, rather than being resolved during the source extraction process.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"54 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144211405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multifrequency simultaneous VLBA view of the radio source 3C 111","authors":"V. Bartolini, D. Dallacasa, J. L. Gómez, M. Giroletti, R. Lico, J. D. Livingston","doi":"10.1051/0004-6361/202449878","DOIUrl":"https://doi.org/10.1051/0004-6361/202449878","url":null,"abstract":"<i>Context.<i/> Relativistic jets originating at the center of active galactic nuclei are embedded in extreme environments with strong magnetic fields and high particle densities, which makes them a fundamental tool for studying the physics of magnetized plasmas.<i>Aims.<i/> We aim to investigate the magnetic field structure and the parsec and sub-parsec properties of the relativistic jet in the radio galaxy 3C 111. Rotation measure (<i>RM<i/>) studies of nearby radio-galaxies, such as this one, provide a valuable tool with which to investigate the transversal magnetic field properties.<i>Methods.<i/> We used multifrequency simultaneous Very Long Baseline Array (VLBA) data from 5 GHz up to 87.6 GHz. We performed an analysis of both total intensity and polarization maps to study the jet magnetic field and infer the spectral properties of the synchrotron emission. We modeled the brightness distribution of the source with multiple 2D Gaussian components to characterize individual emission features.<i>Results.<i/> After determining the core shift (<i>r<i/><sub>c<sub/> ∝ <i>ν<i/><sup>−1.27 ± 0.17<sup/>), we computed the spectral index maps for all the adjacent frequency pairs and found different distributions for the core region (<i>α<i/><sub>max<sub/> ≈ 1.5 and <i>α<i/><sub>min<sub/> ≈ 0.2) and the jet (<i>α<i/> ≈ −1.5 on average) with an unusual optically thick or flat feature in it at ≈1 − 2 pc from the core. Using modelfit, we found a total of 56 components at different frequencies. By putting constraints on the size and position, we identified 22 components at different frequencies for which we computed the equipartition magnetic field. We computed the rotation measure at two different triplets of frequencies. At 15.2 − 21.9 − 43.8 GHz, we discovered high values of <i>RM<i/> in the same region where the optically thick or flat feature was found. This can be associated with a high electron density value at ≈1 − 2 pc from the core that we interpret as originating in a cloud of the clumpy torus. At 5 − 8.4 − 15.2 GHz, we found a distribution of the electric vector position angles and significant <i>RM<i/> transverse gradient that provide strong evidence of a helical configuration of the magnetic field, as found in simulations.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"247 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144211515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A post-common-envelope binary with double-peaked Balmer emission lines from TMTS","authors":"Qichun Liu, Xiaofeng Wang, Jie Lin, Chengyuan Wu, Chunqian Li, Alexei V. Filippenko, Thomas G. Brink, Yi Yang, Weikang Zheng, Cheng Liu, Cuiying Song, Mikhail Kovalev, Hongwei Ge, Fenghui Zhang, Xiaobin Zhang, Qiqi Xia, Haowei Peng, Gaobo Xi, Jun Mo, Shengyu Yan, Jianrong Shi, Jiangdan Li, Tuan Yi","doi":"10.1051/0004-6361/202553732","DOIUrl":"https://doi.org/10.1051/0004-6361/202553732","url":null,"abstract":"<i>Context.<i/> The dynamical method provides an efficient way to discover post-common-envelope binaries (PCEBs) with faint white dwarfs (WDs), thanks to the development of time-domain survey projects. As close binary systems undergo a common-envelope phase, they offer unique opportunities to study the astrophysical processes associated with binary evolution.<i>Aims.<i/> We perform a comprehensive analysis of the PCEB system TMTS J15530469+4457458 (J1553), discovered by the Tsinghua University-Ma Huateng Telescopes for Survey, to explore its physical origin and evolutionary fate.<i>Methods.<i/> This system is characterized by double-peaked Balmer emission lines, and we applied a cross-correlation function to derive its radial velocity (RV) from a series of phase-resolved Keck spectra. The physical parameters of this binary were obtained by fitting the light curves and RV simultaneously. The locations of the Balmer lines were inferred from Doppler tomography, and a MESA simulation was performed to explore the evolution of this system.<i>Results.<i/> Analyses using the cross-correlation function suggest that this system is a single-lined spectroscopic binary and only one star is optically visible. Further analysis through Doppler tomography indicates that J1553 is a detached binary without an accretion disk. Under such a configuration, the simultaneous light-curve and RV fitting reveal that this system contains an unseen WD with mass <i>M<i/><sub>A<sub/> = 0.56±0.09 <i>M<i/><sub>⊙<sub/>, and an M4 dwarf with mass <i>M<i/><sub>B<sub/> = 0.37±0.02 <i>M<i/><sub>⊙<sub/> and radius <i>R<i/><sub>B<sub/> = 0.403<sup>+0.014<sup/><sub>-0.015<sub/>. The extra prominent Balmer emission lines seen in the spectra can trace the motion of the WD; these lines are likely formed near the WD surface as a result of wind accretion. According to the MESA simulation, J1553 could have evolved from a binary consisting of a 2.0–4.0 <i>M<i/><sub>⊙<sub/> zero-age-main-sequence star and an M dwarf with an initial orbital period <i>P<i/><sub><i>i<i/><sub/>≈201−476 d, and the system has undergone a common-envelope (CE) phase. After about 3.3×10<sup>6<sup/> yr, J1553 should evolve into a cataclysmic variable, with a transient state as a supersoft X-ray source at the beginning. J1553 is an excellent system for studying wind accretion, CE ejection physics, and binary evolution theory.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"40 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144176587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}