New Astronomy最新文献

{"title":"Modified Chaplygin gas solutions of f(Q) theory of gravity","authors":"Bhupendra Kumar Shukla ,&nbsp;R.K. Tiwari ,&nbsp;A. Beesham ,&nbsp;Değer Sofuoğlu","doi":"10.1016/j.newast.2025.102355","DOIUrl":"10.1016/j.newast.2025.102355","url":null,"abstract":"<div><div>In this study, we investigate Modified Chaplygin gas solutions within the framework of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>)</mo></mrow></mrow></math></span> theory of gravity, a modified gravitational theory that seeks to address the limitations of the conventional Lambda cold dark matter model. <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>)</mo></mrow></mrow></math></span> gravity offers a novel perspective on cosmic dynamics by incorporating a non-minimal coupling between the geometry and the matter, allowing for a richer understanding of the expansion of the universe. We explore the implications of modified Chaplygin gas, characterized by its unique equation of state (eos), which transitions from a matter-dominated phase to a dark energy-dominated phase, thereby influencing the evolution of the energy density and pressure across cosmic redshifts. Our findings reveal significant insights into the interplay between different energy components, highlighting the transition from positive to negative pressure as a hallmark of the role of dark energy in driving the accelerated expansion of the universe. This research not only enhances our comprehension of cosmic evolution, but also provides a compelling framework for future investigations into the nature of dark energy and its impact on the ultimate fate of the universe.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"117 ","pages":"Article 102355"},"PeriodicalIF":1.9,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"First photometric investigation of V517 Cam combined with ground-based and TESS data","authors":"Neslihan Alan ,&nbsp;Fahri Aliçavuş ,&nbsp;Mehmet Alpsoy","doi":"10.1016/j.newast.2025.102352","DOIUrl":"10.1016/j.newast.2025.102352","url":null,"abstract":"<div><div>The observations of eclipsing binary systems are of great importance in astrophysics, as they allow direct measurements of fundamental stellar parameters. By analysing high-quality space-based observations with ground-based photometric data, it becomes possible to detect these fundamental parameters with greater precision using multicolour photometry. Here, we report the first photometric analysis results of the V517 Cam eclipsing binary system by combining the Transiting Exoplanet Survey Satellite (<em>TESS</em>) light curve and new CCD observations in <em>BVRI</em> filters, obtained with a 60 cm robotic telescope (T60) at the TÜBİTAK National Observatory. By means of photometric analyses, the masses and radii of the primary and secondary stars were carefully determined to be <span><math><mrow><msub><mrow><mi>M</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>=</mo><mn>1</mn><mo>.</mo><mn>47</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>06</mn><mspace></mspace><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>M</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>79</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>05</mn><mspace></mspace><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span>, and <span><math><mrow><msub><mrow><mi>R</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>=</mo><mn>1</mn><mo>.</mo><mn>43</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>03</mn><mspace></mspace><msub><mrow><mi>R</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>75</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>04</mn><mspace></mspace><msub><mrow><mi>R</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span>, respectively. Furthermore, the distance to V517 Cam was calculated to be <span><math><mrow><mn>284</mn><mo>±</mo><mn>20</mn></mrow></math></span> pc. The overall age of the system is estimated to be around <span><math><mrow><mn>63</mn><mo>±</mo><mn>15</mn></mrow></math></span> Myr. At this age, the primary component stands near the onset of its main-sequence evolution, near the ZAMS, whereas the secondary component remains in the pre-main-sequence evolutionary phase. To better understand the evolutionary status and nature of V517 Cam, the mass ratio and temperature values, obtained with relatively low sensitivity by photometric measurements, need to be confirmed by spectral analysis.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"117 ","pages":"Article 102352"},"PeriodicalIF":1.9,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143152960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Prediction of solar cycles 26 and 27 based on LSTM-FCN","authors":"Shuguang Zeng ,&nbsp;Shuo Zhu ,&nbsp;Yao Huang ,&nbsp;Xiangyun Zeng ,&nbsp;Sheng Zheng ,&nbsp;Linhua Deng","doi":"10.1016/j.newast.2025.102353","DOIUrl":"10.1016/j.newast.2025.102353","url":null,"abstract":"<div><div>Predicting solar activity changes is crucial for Earth’s climate, communication systems, and aerospace technology. This study employs the Long Short-Term Memory Fully Convolutional Network (LSTM-FCN) deep learning method to predict the amplitudes and peak times of Solar Cycles (SCs) 26 and 27 for both the entire solar disk and the northern and southern hemispheres. The experimental data comprises the monthly mean total Sunspot Number (SSN) data and the monthly mean northern and southern Hemispheric Sunspot Number (HSN) data, provided by the World Data Center — Sunspot Index and Long-term Solar Observations (WDC-SILSO). The experimental process tested the Input–Output Window Ratio (IOWR) from 4:1 to 14:1, and the results indicate that when the IOWR is 10:1, the normalized Relative RMSE (RRMSE) is minimized at 0.078. According to the prediction, SC 26 is expected to peak in June 2034 with an amplitude of 194.4, and SC 27 is expected to peak in July 2045 with an amplitude of 244.2. It was also found that SC 26 and SC 27 have northern and southern hemisphere asymmetry. This study demonstrates the potential application of the LSTM-FCN deep learning method in forecasting SCs, providing a new tool and approach for solar physics research.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"117 ","pages":"Article 102353"},"PeriodicalIF":1.9,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 distortion solution for the 1-m telescope at Yunnan Observatory and its application to the positional measurement of four main-belt asteroids Eugenia(45), Roma(472), Lundmarka(1334) and Autonoma(1465)","authors":"Na Wang ,&nbsp;Kai-Rui Liu ,&nbsp;Zheng-Yang Xue ,&nbsp;Biao-Biao Zhang ,&nbsp;Yi-Cheng Du","doi":"10.1016/j.newast.2024.102351","DOIUrl":"10.1016/j.newast.2024.102351","url":null,"abstract":"<div><div>Four main-belt asteroids Eugenia, Roma, Lundmarka and Autonoma were observed at Yunnan Observatory 1-m telescope in 2022–2023. A total of 66 CCD frames for the four asteroids are observed. In order to improve the astrometry, the geometric distortion (called GD hereafter) of the 1-m telescope is solved. After GD correction, the precision of Eugenia and Autonoma has improved significantly and the standard deviation of the (O-C) residuals is improved by a maximum of 20 mas. The theoretical position of the asteroid is retrieved from the Jet Propulsion Laboratory Horizons system. Our results show that the mean O-Cs(observed minus computed) of the residuals is better than 0.1 arcsec in each direction. The dispersion is better than 0.071 arcsec in each direction.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"116 ","pages":"Article 102351"},"PeriodicalIF":1.9,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143095021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Corrigendum to “A comprehensive study on the K2-type binary V1393 Tau in four-year observations” [Volume 115, NEASPA_102330]","authors":"Ligang Yu ,&nbsp;Shuang Wang ,&nbsp;Michel Raúl ,&nbsp;Liyun Zhang","doi":"10.1016/j.newast.2024.102350","DOIUrl":"10.1016/j.newast.2024.102350","url":null,"abstract":"","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"116 ","pages":"Article 102350"},"PeriodicalIF":1.9,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143095022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"DRsm: Star spectral classification algorithm based on multi-feature extraction","authors":"Jiaming Yang ,&nbsp;Liangping Tu ,&nbsp;Jianxi Li ,&nbsp;Jiawei Miao","doi":"10.1016/j.newast.2024.102349","DOIUrl":"10.1016/j.newast.2024.102349","url":null,"abstract":"<div><div>With the development of information technology, data-driven astronomical research has become a very popular subject. In view of the huge amount of spectral data from the sky, it is necessary to find suitable automatic processing methods to meet the needs of the time. Based on DenseNet model and ResNet model, DRsm (DenseNet ResNet SoftMax) algorithm is built in this paper, which realizes the automatic classification of stellar spectra. There are 6 steps to the DRsm algorithm: (1) Normalization processing: The Min–max normalization function is used to normalize the stellar spectrum to speed up the algorithm. (2) Denoising processing: The Ces algorithm is employed to denoise the stellar spectrum by reducing the photon noise that affects the spectral observations. (3) Composite RGB image: Three channels of an RGB image, corresponding to the gray image generated by the same spectrum. By superimposing the same spectrum, the effective distinguishing features of the stellar spectrum become more apparent and subsequent work is made easier. Here, we have normalized the continuous spectrum of the stellar spectrum, so that the content shown in the RGB image is basically the spectral line information of the star spectrum. At the same time, we analyze the feasibility of data conversion (synthetic RGB image) : using the main spectral line information of the star spectrum as a reference, we investigate whether the relevant pixel position of the synthesized RGB image contains these features. (4) Data enhancement: The Bottom-hat transformation (Top-hat transformation, contrast enhancement algorithm) is used to enhance the converted data, so that the main distinguishing features of the star spectrum are more obvious. (5) Feature extraction: The ResNet model and DenseNet models are used to extract features from stellar spectra, and the RGB image with a scale of 64 × 64 is extracted as a one-dimensional feature vector. (6) Automatic classification: The feature vector is then sent to the SoftMax module where it is automatically classified. The loss function used by the SoftMax module is ‘data set loss + regular term loss’. When the DRsm algorithm is used to automatically classify the spectra of A, B, dM, F, G, gM and K-type stars with R-band signal-to-noise ratio greater than 30, the classification accuracy is 0.96. The classification accuracy of this method is notably higher than that of the CNN(Convolutional Neural Networks)+Bayes, CNN+KNN, CNN+SVM, CNN+AdaBoost, and CNN+RF algorithms, which achieved accuracies of 0.862, 0.876, 0.894, 0.868, and 0.889, respectively.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"116 ","pages":"Article 102349"},"PeriodicalIF":1.9,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143095020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Non-Newtonian gravity in color-flavor locked strange stars and the 2.6M⊙ component in GW190814","authors":"Chun-Mei Pi ,&nbsp;Shu-Hua Yang","doi":"10.1016/j.newast.2024.102347","DOIUrl":"10.1016/j.newast.2024.102347","url":null,"abstract":"<div><div>We investigate the effects of non-Newtonian gravity on the properties of the color-flavor locked strange stars and constrain the parameters of the strange quark matter model using the mass of the GW190814’s secondary component (<span><math><mrow><mn>2</mn><mo>.</mo><mn>5</mn><msubsup><mrow><mn>9</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>09</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>08</mn></mrow></msubsup><mspace></mspace><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span>). We find that the allowed region in the <span><math><msubsup><mrow><mi>B</mi></mrow><mrow><mi>eff</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>4</mn></mrow></msubsup></math></span>–<span><math><mi>Δ</mi></math></span> parameter space (<span><math><msub><mrow><mi>B</mi></mrow><mrow><mi>eff</mi></mrow></msub></math></span> is the effective bag constant and <span><math><mi>Δ</mi></math></span> is the pairing gap) becomes larger and the minimum allowed value of <span><math><mi>Δ</mi></math></span> becomes smaller with the increasing of the non-Newtonian gravity parameter <span><math><mrow><msup><mrow><mi>g</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>/</mo><msup><mrow><mi>μ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span>. For small values of <span><math><mrow><msup><mrow><mi>g</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>/</mo><msup><mrow><mi>μ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span>, the color-flavor locked phase must be employed to support a static <span><math><mrow><mn>2</mn><mo>.</mo><mn>6</mn><mspace></mspace><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span> strange star. However, if <span><math><mrow><msup><mrow><mi>g</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>/</mo><msup><mrow><mi>μ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> is large enough, the maximum mass of the static strange stars made of unpaired strange quark matter could be larger than <span><math><mrow><mn>2</mn><mo>.</mo><mn>6</mn><mspace></mspace><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span>. Specifically, for the cases of <span><math><mrow><msub><mrow><mi>a</mi></mrow><mrow><mn>4</mn></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>6</mn></mrow></math></span>, 0.7, and 0.8 (<span><math><msub><mrow><mi>a</mi></mrow><mrow><mn>4</mn></mrow></msub></math></span> is the perturbative quantum chromodynamics corrections term), the turning points are <span><math><mrow><msup><mrow><mi>g</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>/</mo><msup><mrow><mi>μ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>=</mo><mn>2</mn><mo>.</mo><mn>15</mn></mrow></math></span>, 3.59, and 4.75 GeV⁻², respectively.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"116 ","pages":"Article 102347"},"PeriodicalIF":1.9,"publicationDate":"2024-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143095025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Insights from modelling magnetar-driven light curves of stripped-envelope supernovae","authors":"Amit Kumar","doi":"10.1016/j.newast.2024.102346","DOIUrl":"10.1016/j.newast.2024.102346","url":null,"abstract":"<div><div>This work presents the semi-analytical light curve modelling results of 11 stripped-envelope SNe (SESNe), where millisecond magnetars potentially drive their light curves. The light-curve modelling is performed utilizing the <span><math><msup><mrow><mi>χ</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span>-minimization code <span>MINIM</span> considering millisecond magnetar as a central engine powering source. The magnetar model well regenerates the bolometric light curves of all the SESNe in the sample and constrains numerous physical parameters, including magnetar’s initial spin period (<span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span>) and magnetic field (<span><math><mi>B</mi></math></span>), explosion energy of supernova (<span><math><msub><mrow><mi>E</mi></mrow><mrow><mtext>exp</mtext></mrow></msub></math></span>), progenitor radius (<span><math><msub><mrow><mi>R</mi></mrow><mrow><mtext>p</mtext></mrow></msub></math></span>), etc. Within the sample, the superluminous SNe 2010kd and 2020ank exhibit the lowest <span><math><mi>B</mi></math></span> and <span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span> values, while the relativistic Ic broad-line SN 2012ap shows the highest values for both parameters. The explosion energy for all SESNe in the sample (except SN 2019cad), exceeding <span><math><mo>≳</mo></math></span>2 × 10⁵¹ erg, indicates there is a possibility of a jittering jet explosion mechanism driving these events. Additionally, a correlation analysis identifies linear dependencies among parameters derived from light curve analysis, revealing positive correlations between rise and decay times, <span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span> and <span><math><mi>B</mi></math></span>, <span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span> and <span><math><msub><mrow><mi>R</mi></mrow><mrow><mtext>p</mtext></mrow></msub></math></span>, and <span><math><msub><mrow><mi>E</mi></mrow><mrow><mtext>exp</mtext></mrow></msub></math></span> and <span><math><msub><mrow><mi>R</mi></mrow><mrow><mtext>p</mtext></mrow></msub></math></span>, as well as strong anti-correlations of <span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span> and <span><math><mi>B</mi></math></span> with the peak luminosity. Principal Component Analysis is also applied to key parameters to reduce dimensionality, allowing a clearer visualization of SESNe distribution in a lower-dimensional space. This approach highlights the diversity in SESNe characteristics, underscoring unique physical properties and behaviour across different events in the sample. This study motivates further study on a more extended sample of SESNe to look for millisecond magnetars as their powering source.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"116 ","pages":"Article 102346"},"PeriodicalIF":1.9,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143095035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global Transonic Solution of magnetized dissipative accretion flow around non-rotating black holes with thermal conduction","authors":"Sakine Rezaie ,&nbsp;Maryam Ghasemnezhad,&nbsp;Mojtaba Golshani","doi":"10.1016/j.newast.2024.102348","DOIUrl":"10.1016/j.newast.2024.102348","url":null,"abstract":"<div><div>Our goal is to obtain a set of global transonic accretion solutions for magnetized dissipative accretion flows around non-rotating black holes. To achieve this, we have considered a steady state, axisymmetric, and viscous advection-dominated accretion disc. Additionally, we have investigated the effects of thermal conduction and bremsstrahlung cooling on hot accretion flow. We also have examined the properties of the dynamical variables of the flow in their presence. We have found that the nature of transonic solutions is modified by changing the thermal conduction parameter and cooling factor. We have determined the critical values of the thermal conduction and cooling parameters that provide the global accretion solutions. Furthermore, we have estimated the disc’s luminosity in our model and have applied it to Sgr A<span><math><msup><mrow></mrow><mrow><mo>∗</mo></mrow></msup></math></span></div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"116 ","pages":"Article 102348"},"PeriodicalIF":1.9,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143095036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"How inclusion of binaries affects the fitting of giant branches and determination of fundamental parameters of star clusters","authors":"Yun Zhou,&nbsp;Zhongmu Li","doi":"10.1016/j.newast.2024.102342","DOIUrl":"10.1016/j.newast.2024.102342","url":null,"abstract":"<div><div>Open clusters (OCs) play an important role in the study of star formation and the structural evolution of the Milky Way. This paper fits the color-magnitude diagrams (CMDs) of 17 OCs using a tool called Powerful CMD, with the aim of studying the effect of inclusion of binary stars on the fitting of cluster CMDs with clear giant branches. The fitting results of these star clusters were analyzed and compared under two scenarios, i.e., single-star isochrone fitting and binary-star isochrone fitting. In the binary-star isochrone fitting, the binary fraction is greater than 0 and no larger than 1, which is determined by Powerful CMD based on the goodness of fit to the CMD. The research findings indicate that binaries enhance the goodness of fit for all sample star clusters. In particular, the fit to giant branches becomes better when binary stars are considered. Furthermore, binaries contribute to improving accuracy in determining the fundamental parameters such as age, color excess, and distance modulus for star clusters, because the parameter uncertainties become smaller when binary stars are included in theoretical models. Moreover, the distance modulus and age of clusters become larger when binary-star isochrones are used instead single-star isochrones. The results suggest that one should not neglect the influence of binaries on the shape of giant branches and their role in determining fundamental parameters, in the CMD studies of star clusters.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"116 ","pages":"Article 102342"},"PeriodicalIF":1.9,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143095023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}