New Astronomy最新文献

{"title":"Analysis and simulations of binary black hole merger spins — The question of spin-axis tossing at black hole formation","authors":"Hans C.G. Larsen ,&nbsp;Casper C. Pedersen ,&nbsp;Thomas M. Tauris ,&nbsp;Ali Sepas ,&nbsp;Claudia Larsen ,&nbsp;Christophe A.N. Biscio","doi":"10.1016/j.newast.2025.102459","DOIUrl":"10.1016/j.newast.2025.102459","url":null,"abstract":"<div><div>The origin of binary black hole (BH) mergers remains a topic of active debate, with effective spins (<span><math><msub><mrow><mi>χ</mi></mrow><mrow><mi>eff</mi></mrow></msub></math></span>) measured by the LIGO-Virgo-KAGRA (LVK) Collaboration providing crucial insights. In this study, our objective is to investigate the empirical <span><math><msub><mrow><mi>χ</mi></mrow><mrow><mi>eff</mi></mrow></msub></math></span> distribution (and constrain individual spin components) of binary BH mergers and compare them with extensive simulations, assuming that they originate purely from isolated binaries or a mixture of formation channels. We explore scenarios using BH kicks with and without the effect of spin-axis tossing during BH formation. We employ simple yet robust Monte Carlo simulations of the final core collapse forming the second-born BH, using minimal assumptions to ensure transparency and reproducibility. The synthetic <span><math><msub><mrow><mi>χ</mi></mrow><mrow><mi>eff</mi></mrow></msub></math></span> distribution is compared to the empirical data from LVK science runs O1–O3 using functional data analysis, kernel density estimations, and three different statistical tests, accounting for data uncertainties. We find strong indications for spin-axis tossing during BH formation if LVK sources are dominated by the isolated binary channel. Simulations with spin-axis tossing achieve high p-values (up to 0.882) using Kolmogorov–Smirnov, Cramer-von Mises, and Anderson–Darling tests, while without tossing, all p-values drop below 0.001 for isolated binaries. A statistically acceptable solution without tossing, however, emerges if <span><math><mrow><mo>∼</mo><mn>72</mn><mspace></mspace><mo>±</mo><mspace></mspace><mn>8</mn><mtext>%</mtext></mrow></math></span> of detected binary BH mergers result from dynamical interactions causing random BH spin directions. Finally, for an isolated binary origin, we find a preference for mass reversal in <span><math><mrow><mo>∼</mo><mn>30</mn><mtext>%</mtext></mrow></math></span> of the progenitor binaries. Predictions from this study can be tested with LVK O4+O5 data as well as the 3G detectors, Einstein Telescope and Cosmic Explorer, enabling improved constraints on formation channel ratios and the critical question of BH spin-axis tossing.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102459"},"PeriodicalIF":2.1,"publicationDate":"2025-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144886242","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":"Unlocking the hidden potential of pulsar astronomy","authors":"D. Kaur ,&nbsp;G. Hobbs ,&nbsp;A. Zic ,&nbsp;J.R. Dawson ,&nbsp;J. Morgan ,&nbsp;W. Ling ,&nbsp;S. Camtepe ,&nbsp;J. Pieprzyk ,&nbsp;M.C.M. Cheung","doi":"10.1016/j.newast.2025.102460","DOIUrl":"10.1016/j.newast.2025.102460","url":null,"abstract":"<div><div>Pulsars have traditionally been used for research into fundamental physics and astronomy. In this paper, we investigate the expanding applications of radio pulsars in societal and industrial domains beyond their conventional scientific roles. We describe emerging applications in positioning, navigation, timing and synchronization, random number generation, space weather monitoring, public engagement, antenna calibration techniques, and leveraging extensive pulsar data sets generated by large-scale observatories. Such pulsar data sets have already been used to demonstrate quantum-computing algorithms.</div><div>We evaluate the potential for compact radio receiver systems for pulsar detection by describing optimal observing bands. We show that relatively simple and compact receiver systems can detect the brightest pulsar, Vela. The equivalent of an <span><math><mrow><mo>∼</mo><mn>4</mn></mrow></math></span> <!--> <!-->m-diameter dish with a small bandwidth operating around 700<!--> <!-->MHz would be able to detect many more pulsars. Such a detector would be able to localize itself to around 10<!--> <!-->km using pulsar navigation techniques.</div><div>The space weather community requires direct measurements of the integrated electron density at a range of solar elongations. The only method to get model-independent values is through pulsar observations and we explore the possibility of measuring dispersion measures (DMs) (and rotation measures) with a range of telescopes (observing from low to mid-frequencies) as well as using a typical model to predict the variation of the DM as a function of solar radii. We review how pulsars can be used to produce random sequences and demonstrate that such sequences can be produced using the scintillation properties of pulsars as well as from pulse jitter.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102460"},"PeriodicalIF":2.1,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144830951","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":"A critical reanalysis of supernova type Ia data","authors":"Ramanpreet Singh ,&nbsp;Athul C.N. ,&nbsp;H.K. Jassal","doi":"10.1016/j.newast.2025.102454","DOIUrl":"10.1016/j.newast.2025.102454","url":null,"abstract":"<div><div>Cosmological parameter fitting remains crucial, especially with the abundance of available data. While many parameters have been tightly constrained, discrepancies — most notably the Hubble tension — persist between measurements obtained from different observational datasets. In this paper, we re-examine the Pantheon supernova dataset to explore deviations in the distribution of distance modulus residuals from the Gaussian distribution, which is typically the underlying assumption. We do this analysis for the concordant cosmological constant model and for a variety of dynamical dark energy models. It has been shown earlier that the residuals in this dataset are better fit to a logistic distribution. We compare the residual distributions assuming both Gaussian and Logistic likelihoods on the complete dataset, as well as various subsets of the data. The results, validated through various statistical tests, demonstrate that the Logistic likelihood provides a better fit for the full dataset and lower redshift bins, while higher redshift bins fit Gaussian and Logistic likelihoods similarly. Furthermore, the findings indicate a preference for a cosmological constant model. However analysing individual surveys within the Pantheon dataset reveals inconsistencies among subsets. The level of agreement between surveys varies depending upon the underlying likelihood function.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102454"},"PeriodicalIF":2.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721791","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":"Exploring the evolution of a non-static plane symmetric universe with cosmic strings and LVDP in f(Q) gravity","authors":"Syed Mudassir Syed Iqbal,&nbsp;G.U. Khapekar","doi":"10.1016/j.newast.2025.102455","DOIUrl":"10.1016/j.newast.2025.102455","url":null,"abstract":"&lt;div&gt;&lt;div&gt;In this study, we have investigated the non-static plane symmetric space–time with perfect fluid containing cosmic string in the frame work of &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;mfenced&gt;&lt;mrow&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfenced&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; gravity in which the non-metricity scalar &lt;span&gt;&lt;math&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; describes the gravitational interaction. To find exact solutions for the field equations, we assume the metric potentials relation as &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;e&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;h&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, where &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mo&gt;≠&lt;/mo&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; is an arbitrary constant and the linearly varying deceleration parameter &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;mfenced&gt;&lt;mrow&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfenced&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, where &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;mo&gt;≥&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;≥&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; are constants. We estimate the best-fit values of the model parameters using the Observational Hubble Data (OHD) comprising 31 data points of Cosmic Chronometers (CC) and the Pantheon+SHOES dataset comprising 1701 data points, employing the minimum chi-square method and the Markov Chain Monte Carlo (MCMC) technique, yielding &lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;08&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;09&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mn&gt;74&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;07&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;32&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;30&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; for OHD, and &lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;80&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;07&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;07&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mn&gt;74&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;63&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;22&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;21&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; for Pantheon+SHOES dataset. The evolution of the deceleration parameter indicates transition from an early decelerating phase to the current accelerating expansion phase of the universe in our model. Furthermore, the evolution of the deceleration parameter predicts a future transition into a super-acceleration phase of the universe. Moreover, to explore some key cosmological quantities such as energy density, pressure, equation of state parameter, the string tension density, we consider the quadrati","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102455"},"PeriodicalIF":1.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144713342","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 “The first photometric and dynamical study of the eclipsing binary star V951 Perseus” [New Astronomy, Vol 119, October 2025, 102418]","authors":"Bin Zhang ,&nbsp;Wei Tao ,&nbsp;Zhen Zhong","doi":"10.1016/j.newast.2025.102456","DOIUrl":"10.1016/j.newast.2025.102456","url":null,"abstract":"","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102456"},"PeriodicalIF":2.1,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009961","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":"Complex rotations of the asteroid 45 Eugenia","authors":"V.I. Borodin ,&nbsp;M.A. Bubenchikov ,&nbsp;A.M. Bubenchikov ,&nbsp;D.S. Kaparulin ,&nbsp;D.V. Mamontov","doi":"10.1016/j.newast.2025.102458","DOIUrl":"10.1016/j.newast.2025.102458","url":null,"abstract":"<div><div>The class of inertial rotation of the celestial object (45) Eugenia is considered. Using a new original method for calculating angular dynamics in absolute axes, it is shown that tumbling motion of Eugenia occur at any tilt of the large diameter to the axis of the initial rotation. All possible spin states of the asteroid are determined. The conditions under which the most active rotations of the object under consideration occur are found.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102458"},"PeriodicalIF":1.9,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144715757","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":"Learning from core-collapse supernova remnants on the explosion mechanism","authors":"Noam Soker","doi":"10.1016/j.newast.2025.102453","DOIUrl":"10.1016/j.newast.2025.102453","url":null,"abstract":"<div><div>I estimate some typical properties of the jittering jets explosion mechanism (JJEM) to distinguish it from competing supernova explosion models. From the imprints of jittering jets in the outskirts of some CCSN remnants, I estimate the half-opening angles of jittering jets that shape CCSN remnants to be <span><math><mrow><msub><mrow><mi>α</mi></mrow><mrow><mi>j</mi></mrow></msub><mo>≃</mo><msup><mrow><mn>1</mn></mrow><mrow><mo>∘</mo></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>∘</mo></mrow></msup></mrow></math></span>. I also estimate that intermittent accretion disks around the newly born neutron star (NS) can launch jets after they live for only several times their orbital period around the NS. To operate, the JJEM requires intermittent accretion disks that launch jets to amplify the magnetic fields in a dynamo, and the magnetic fields to reconnect and release their energy rapidly. I estimate the width of magnetic field reconnection zones to be <span><math><mrow><msub><mrow><mi>D</mi></mrow><mrow><mi>rec</mi></mrow></msub><mo>≈</mo><mn>0</mn><mo>.</mo><mn>005</mn><mi>r</mi><mo>≈</mo><mn>0</mn><mo>.</mo><mn>1</mn><mspace></mspace><mi>km</mi></mrow></math></span> near the surface of the NS. This width requires a numerical resolution several times smaller than the resolution of present CCSN simulations. I argue, therefore, that existing simulations of the CCSN explosion mechanism are still far from correctly simulating CCSN explosions.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102453"},"PeriodicalIF":1.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144672215","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":"Optical flickering in Mira and mass accretion rate onto the companion white dwarf","authors":"R.K. Zamanov ,&nbsp;B. Spassov ,&nbsp;R. Konstantinova-Antova ,&nbsp;M. Moyseev ,&nbsp;J. Marti ,&nbsp;M.F. Bode ,&nbsp;V. Vujcic ,&nbsp;V. Sreckovic","doi":"10.1016/j.newast.2025.102452","DOIUrl":"10.1016/j.newast.2025.102452","url":null,"abstract":"<div><div>We report photometric observations in Johnson <span><math><mi>B</mi></math></span> and <span><math><mi>V</mi></math></span> bands of the short term variability (flickering) of Mira – the prototypical pulsating asymptotic giant branch (AGB) star. The observations are performed over 4 consecutive nights (24–28 November 2024), during the last minimum of the Mira pulsation. The peak-to-peak amplitude observed is 0.25-0.34 mag in <span><math><mi>B</mi></math></span> band and 0.14-0.19 mag in <span><math><mi>V</mi></math></span> band. For the flickering source we find colour <span><math><mrow><msub><mrow><mrow><mo>(</mo><mi>B</mi><mo>−</mo><mi>V</mi><mo>)</mo></mrow></mrow><mrow><mn>0</mn></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>44</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>11</mn></mrow></math></span>, temperature <span><math><mrow><mn>7000</mn><mo>±</mo><mn>700</mn></mrow></math></span> K, and average radius <span><math><mrow><msub><mrow><mi>R</mi></mrow><mrow><mi>f</mi><mi>l</mi></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>30</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>07</mn></mrow></math></span> R<span><math><msub><mrow></mrow><mrow><mo>⊙</mo></mrow></msub></math></span>. Assuming the mass of the white dwarf <span><math><mrow><mo>≈</mo><mn>0</mn><mo>.</mo><mn>6</mn></mrow></math></span> M<span><math><msub><mrow></mrow><mrow><mo>⊙</mo></mrow></msub></math></span>, we estimate a mass accretion rate <span><math><mrow><mo>≈</mo><mn>6</mn><mo>.</mo><mn>0</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>10</mn></mrow></msup></mrow></math></span> M<span><math><msub><mrow></mrow><mrow><mo>⊙</mo></mrow></msub></math></span> yr⁻¹ during our observations.</div><div>The data will be available on Zenodo.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102452"},"PeriodicalIF":1.9,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144655902","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":"Impacts of variable mass disk on region and stability of motion around triangular equilibrium points of the R3BP with variable mass binaries Maxi J1659-152 and Kepler-16","authors":"Veronica Cyril-Okeme ,&nbsp;Oni Leke ,&nbsp;Jessica Gyegwe","doi":"10.1016/j.newast.2025.102457","DOIUrl":"10.1016/j.newast.2025.102457","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The paper explores the impacts of variable mass disk on region and stability of motion of a dust grain around the triangular equilibrium points (TEPs) of the circular restricted three-body problem (R3BP), with variable mass binaries &lt;strong&gt;Maxi J1659-152&lt;/strong&gt; and &lt;strong&gt;Kepler-16&lt;/strong&gt;. The masses of the binaries vary with time under the Mestschersky unified law (MUL) and their motion is described by the Gylden-Mestschersky problem (GMP), with the assumption that the system is enclosed by a non-discrete disk of dust whose mass is also assumed to vary with time under the description of the MUL. Both secondary bodies in the binaries are assumed to be radiation emitters. The time varying system of equations are deduced and transformed to the autonomized equations with constant coefficients. The TEPs of the autonomized and non-autonomous systems are investigated and it is seen that there exists a pair of TEPs defined by the mass parameter&lt;span&gt;&lt;math&gt;&lt;mi&gt;υ&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;, mass of disk&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;and the mass variation parameter&lt;span&gt;&lt;math&gt;&lt;mi&gt;κ&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;, for the autonomized system while those of the non-autonomous system additionally are defined by a function of time&lt;span&gt;&lt;math&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;. It is seen that the radial and vertical scale lengths of the disk affects the locations of the TEPs but this impact depends largely on the mass of the disk. Further, the impacts of the varying disks masses on the zero velocity curves (ZVC) of the dust grain around the TEPs, is investigated, and it is seen that, as the disk mass is increasing, the energy level decreases and the region where motion of the dust grain is forbidden increases. Additionally, the regions where motion is allowed around the binaries and the TEPs are determined by the disks masses. Next, we investigate the linear stability of the TEPs of the autonomized system and found it to be stable in some interval of the masses of the disks for both binaries. The TEPs of the non-autonomous system are unstable due to time&lt;span&gt;&lt;math&gt;&lt;mi&gt;t&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;. To validate the linear stability, we explore the orbital numerical integration around the TEPs and calculated the Lyapunov exponent indicator (LEI) for different masses of the disks. It was observed that the orbits are stable in the interval of the linear stability and their corresponding LEI tend to zero. Finally, we analyze the Poincaré surface of sections (PSS) around the TEPs for the binaries and found that in the range of linearly unstable TEPs, chaos exists while periodic, quasi-periodic trajectories and islands exist in the range of the linearly stable TEPS. This model can be used to analyze the long-term motion of satellites and planets in binary systems with mass variations of disk in the environment. This model can be used to analyze the long-term motion of satellites and planets in binary systems with mass variations of disk in the environment.&lt;/div","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102457"},"PeriodicalIF":1.9,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144680399","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":"WGAN-based molecular clumps generation","authors":"Tieliang Yu ,&nbsp;Xinqiong Liu ,&nbsp;Yao Huang ,&nbsp;Sheng Zheng ,&nbsp;Xiaoyu Luo ,&nbsp;Chen Long","doi":"10.1016/j.newast.2025.102451","DOIUrl":"10.1016/j.newast.2025.102451","url":null,"abstract":"<div><div>In this paper, a new molecular clumps generation algorithm based on the Wasserstein Generative Adversarial Network (WGAN) is investigated for the problem that the simulated molecular clumps generated by the traditional Gaussian model have a large difference from the measured clumps. The method first generates position–position intensity map of the clump using WGAN and then performs 3D expansion in the direction of the velocity axis using a Gaussian function containing weak noise, which ultimately generates 3D simulated molecular clumps in position–position–velocity (PPV) space. Semi-supervised molecular clumps validation algorithm (SS-3D-Clump) is utilized to validate the 3D molecular clumps data generated by the method, and the confidence level of them are above 0.999. Experimentally, it is proved that the new method can provide simulated clumps with morphology and intensity closer to the measured clumps. The simulated molecular clumps are used on the one hand to generate PPV data in combination with measured backgrounds for testing the performance of molecular clump detection algorithms; on the other hand, they can also be used to supplement the 3D molecular clump samples. Experiments have demonstrated that, if 30%–50% of the measured positive samples are retained in the VoxNet training set, and the rest are simulated clumps generated, the classification accuracy can also be guaranteed.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102451"},"PeriodicalIF":1.9,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580361","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}