New Astronomy最新文献

{"title":"Near-IR spectroscopy of the gravitationally lensed quasar PS J0147+4630","authors":"Luis J. Goicoechea ,&nbsp;Vyacheslav N. Shalyapin","doi":"10.1016/j.newast.2025.102479","DOIUrl":"10.1016/j.newast.2025.102479","url":null,"abstract":"<div><div>The quadruply-imaged gravitationally lensed quasar PS J0147+4630 at redshift <span><math><mrow><mi>z</mi><mo>&gt;</mo></mrow></math></span> 2 is a good candidate for time delay cosmography and microlensing-based source structure studies. In this paper, new spectra of its four images are derived from archive data of two 10-m class telescopes. We focus on the unexplored near-IR spectral region including the Mg<!--> <span>ii</span>, H<span><math><mi>β</mi></math></span>, [O<!--> <span>iii</span>] and H<span><math><mi>α</mi></math></span> emission lines (0.9<span><math><mrow><mo>−</mo><mn>2</mn><mo>.</mo><mn>4</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span>), and measure image flux ratios for the emission lines and their underlying continua, as well as a reliable quasar redshift of 2.357 ± 0.002. We also find evidence of an outflow in the H<span><math><mi>α</mi></math></span> emission and estimate a quasar black-hole logarithmic mass <span><math><mrow><mo>log</mo><mfenced><mrow><msub><mrow><mi>M</mi></mrow><mrow><mi>BH</mi></mrow></msub><mo>/</mo><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></mfenced></mrow></math></span> = 9.34 ± 0.30.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102479"},"PeriodicalIF":2.1,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145227244","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":"Numerical study of relativistic jet propagation inside uniform interstellar medium issuing from an Active Galactic Nuclei","authors":"Ribhu Pal,&nbsp;Arnab Roy","doi":"10.1016/j.newast.2025.102467","DOIUrl":"10.1016/j.newast.2025.102467","url":null,"abstract":"<div><div>A direct numerical simulation (DNS) of two-dimensional axisymmetric relativistic jet propagation through a uniform interstellar medium was carried out by solving the relativistic magnetohydrodynamic (RMHD) equations with the PLUTO solver (Mignone et al., 2007). Moreover, a comprehensive discussion of the detailed flow features involved in this propagation is provided throughout this study. The physics underlying shock-vorticity interaction during relativistic jet propagation through a uniform interstellar medium has been thoroughly described in this present study. Additionally, the probability density distribution (p.d.f) of enstrophy (<span><math><mi>ϵ</mi></math></span>) indicates that the highest intensity of fluid rotation, and consequently turbulence, is manifested within the cocoon instead of the frontal region of the relativistic jet.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102467"},"PeriodicalIF":2.1,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158569","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":"Effects of ion source term on the sheath in electronegative dusty plasmas","authors":"S.A. Galyanseyedi ,&nbsp;G. Foroutan ,&nbsp;T. Mohsenpour","doi":"10.1016/j.newast.2025.102476","DOIUrl":"10.1016/j.newast.2025.102476","url":null,"abstract":"<div><div>This study examines a stationary model of the magneto-electronegative dusty plasma sheath, treating dust particles as a cold fluid. In the present model, the electron and negative ion are in Maxwellian thermodynamic equilibrium, while positive ions are considered as a hot fluid with an ion source term. The effects of ion sources and ionization frequencies (IFs) on the sheath are examined to compare their contributions. A modified sheath criterion and floating potential are established theoretically using the Sagdeev potential method. The governing equations of the model are then solved numerically. The effects of the ion source on sheath electric potential, particle density, positive ion velocity, and space charge density are also investigated. It was found that the modified Bohm criterion decreases with an increase of the IF. It can be seen that the different ion source term is effective in the dusty plasma sheath structure.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102476"},"PeriodicalIF":2.1,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109232","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":"High power accretion in massive binary systems and the impact of metallicity","authors":"Bhawna Mukhija ,&nbsp;Amit Kashi","doi":"10.1016/j.newast.2025.102475","DOIUrl":"10.1016/j.newast.2025.102475","url":null,"abstract":"<div><div>During a giant eruption of a very massive star in the binary system, the companion star can accrete a large amount of mass that can change its properties and potentially its subsequent evolution. The effect depends on the companion mass, metallicity, the amount of mass it accreted, orbital parameters and other parameters. We simulate individual companion stars assuming they undergo such accretion events. We study the envelope properties of 20 <span><math><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></math></span> and 30 <span><math><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></math></span> single massive stars at different metallicities (<span><math><mrow><mi>Z</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>02</mn></mrow></math></span>, <span><math><mrow><mi>Z</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>008</mn></mrow></math></span> and <span><math><mrow><mi>Z</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>004</mn></mrow></math></span>) during accretion at different rates, from <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>5</mn></mrow></msup></mrow></math></span> to <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup><mspace></mspace><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub><mspace></mspace><msup><mrow><mi>yr</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span>. For the lower accretion rates we simulate, the stars remains hot, while at higher accretion rates, it becomes cooler and inflates. This behavior is observed in both stars but occurs at different accretion rates. Higher metallicity stars exhibit greater variations in accretion luminosity for the same accretion rate and stellar mass compared to lower metallicity stars. While higher metallicity stars typically have larger stellar envelopes, suggesting smaller variations in luminosity at Galactic metallicity compared to the LMC and SMC, our results show the opposite.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102475"},"PeriodicalIF":2.1,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145049122","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":"Solar energetic particle transport via the heliospheric current sheet: Evidence of a ground-level response on All Saints Day, 2014","authors":"Marcel Nogueira de Oliveira ,&nbsp;Carlos E. Navia ,&nbsp;Andre Asevedo Nepomuceno","doi":"10.1016/j.newast.2025.102468","DOIUrl":"10.1016/j.newast.2025.102468","url":null,"abstract":"<div><div>We investigate the physical mechanisms responsible for the solar energetic particle (SEP) event observed on 1 November 2014, during which several ground-based detectors in both hemispheres, specifically those located on the sunlit western side of Earth, recorded simultaneous enhancements in counting rates. The event is attributed to Active Region (AR) 2192, one of the most active sunspot groups of Solar Cycle 24, which at the time was situated near the western limb of the solar disk, approaching the far side of the Sun. A plausible scenario involves a combination of solar eruptive activity, particle acceleration by a shock wave driven by a coronal mass ejection (CME), and the presence of a heliospheric current sheet (HCS) sector crossing, which may have enhanced magnetic connectivity between the Sun and Earth. We emphasize data from the New-Tupi muon detector, operating in scaler mode and located near the central region of the South Atlantic Anomaly (SAA). The particle excess detected on 1 November 2014 by ground-based instruments spanning different rigidity regimes, in conjunction with satellite observations, indicates that the signal was not a localized phenomenon. Assuming a power-law energy spectrum for the SEP population, we find that its high-energy tail in the GeV range is consistent with proton flux measurements reported by GOES-13. We present and discuss the details of these observations.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102468"},"PeriodicalIF":2.1,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144934278","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":"Dataset of artefacts for machine learning applications in astronomy","authors":"Sreevarsha Sreejith ,&nbsp;Maria V. Pruzhinskaya ,&nbsp;Alina A. Volnova ,&nbsp;Vadim V. Krushinsky ,&nbsp;Konstantin L. Malanchev ,&nbsp;Emille E.O. Ishida ,&nbsp;Anastasia D. Lavrukhina ,&nbsp;Timofey A. Semenikhin ,&nbsp;Emmanuel Gangler ,&nbsp;Matwey V. Kornilov ,&nbsp;Vladimir S. Korolev","doi":"10.1016/j.newast.2025.102466","DOIUrl":"10.1016/j.newast.2025.102466","url":null,"abstract":"<div><div>Accurate photometry in astronomical surveys is challenged by image artefacts, which affect measurements and degrade data quality. Due to the large amount of available data, this task is increasingly handled using machine learning algorithms, which often require a labelled training set to learn data patterns. We present an expert-labelled dataset of 1127 artefacts with 1213 labels from 26 fields in ZTF DR3, along with a complementary set of nominal objects. The artefact dataset was compiled using the active anomaly detection algorithm <span>PineForest</span>, developed by the SNAD team. These datasets can serve as valuable resources for real-bogus classification, catalogue cleaning, anomaly detection, and educational purposes. Both artefacts and nominal images are provided in FITS format in two sizes (28 × 28 and 63 × 63 pixels). The datasets are publicly available for further scientific applications.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102466"},"PeriodicalIF":2.1,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020441","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 detection of ethylene oxide and acetaldehyde in hot core G358.93–0.03 MM1: Tracing prebiotic oxygen chemistry","authors":"Arijit Manna,&nbsp;Sabyasachi Pal","doi":"10.1016/j.newast.2025.102465","DOIUrl":"10.1016/j.newast.2025.102465","url":null,"abstract":"<div><div>Ethylene oxide (c- <figure><img></figure> ) and its isomer, acetaldehyde (CH₃CHO), are important complex organic molecules owing to their potential role in the formation of amino acids (R–CH(NH₂)-COOH) in interstellar medium. The detection of c- <figure><img></figure> in hot molecular cores suggests the possible existence of larger ring-shaped molecules containing more than three carbon atoms, such as furan (c- <figure><img></figure> ), which shares structural similarities with ribose (C₅H₁₀O₅), the sugar component of DNA. In this study, we report the first detection of the rotational emission lines of c- <figure><img></figure> and CH₃CHO towards the hot molecular core G358.93–0.03 MM1, based on observations from the Atacama Large Millimeter/Submillimeter Array (ALMA) in band 7. The fractional abundances of c- <figure><img></figure> and CH₃CHO relative to H₂ are <span><math><mrow><mrow><mo>(</mo><mn>2</mn><mo>.</mo><mn>1</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>2</mn><mo>)</mo></mrow><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup></mrow></math></span> and <span><math><mrow><mrow><mo>(</mo><mn>7</mn><mo>.</mo><mn>1</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>9</mn><mo>)</mo></mrow><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup></mrow></math></span>, respectively. The column density ratio between CH₃CHO and c- <figure><img></figure> is <span><math><mrow><mn>3</mn><mo>.</mo><mn>4</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>7</mn></mrow></math></span>. A Pearson correlation heat map reveals strong positive correlations (<span><math><mi>r</mi></math></span> <span><math><mo>&gt;</mo></math></span> 0.5) between the abundances and excitation temperatures of c- <figure><img></figure> and CH₃CHO, suggesting a possible chemical connection between those two molecules. To investigate this further, we conducted a two-phase warm-up chemical model using the gas-grain chemical code UCLCHEM. A comparison between our derived abundances and the predictions from our chemical model and existence model demonstrates good agreement within factors of 0.73 and 0.74, respectively. We propose that c- <figure><img></figure> may form in G358.93–0.03 MM1 via the grain surface reaction between C₂H₄ and O, but CH₃CHO may be produced through the surface reaction between CH₃ and HCO.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102465"},"PeriodicalIF":2.1,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144934279","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-singular bounce scenario of Higher dimensional dark energy cosmological model in Lyra geometry","authors":"Kangujam Priyokumar Singh,&nbsp;Asem Jotin Meitei","doi":"10.1016/j.newast.2025.102464","DOIUrl":"10.1016/j.newast.2025.102464","url":null,"abstract":"<div><div>In this work, we examine a five-dimensional anisotropic Bianchi type III cosmological model within the framework of Lyra geometry. We investigate the matter bounce scenario under the dark energy condition for the equation of state relationship <span><math><mrow><mi>ρ</mi><mo>=</mo><mi>W</mi><mi>p</mi></mrow></math></span> with <span><math><mrow><mi>W</mi><mo>=</mo><mo>−</mo><mn>1</mn></mrow></math></span>. Utilizing the energy–momentum tensor of a perfect fluid, we derive the solution for the model universe. Our proposed model also evaluates the behavior of energy conditions, state-finders, the current value of the deceleration parameter and stability conditions.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102464"},"PeriodicalIF":2.1,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144886243","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":"Dark energy parametrizations in Einstein–Aether gravity with cubic curvature corrections","authors":"Mithun Bairagi","doi":"10.1016/j.newast.2025.102462","DOIUrl":"10.1016/j.newast.2025.102462","url":null,"abstract":"<div><div>We investigate the late-time cosmic acceleration within the framework of generalized Einstein-Aether gravity incorporating cubic curvature corrections. Employing three widely used dynamical dark energy parametrizations-CPL, JBP, and BA, we reconstruct the cosmic expansion history by constraining the free model parameters using Type Ia Supernova (SN Ia) data from the Pantheon compilations via a <span><math><msup><mrow><mi>χ</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span>-minimization approach. We determine best-fit values for the model parameters and evaluate key cosmological quantities such as the dark energy density <span><math><msub><mrow><mi>Ω</mi></mrow><mrow><msub><mrow><mtext>de</mtext></mrow><mrow><mn>0</mn></mrow></msub></mrow></msub></math></span>,the matter density <span><math><msub><mrow><mi>Ω</mi></mrow><mrow><msub><mrow><mtext>m</mtext></mrow><mrow><mn>0</mn></mrow></msub></mrow></msub></math></span>, the Hubble constant <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>, and the deceleration parameter <span><math><msub><mrow><mi>q</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> of the present universe. We also examine the evolution of the potential <span><math><mrow><mi>V</mi><mrow><mo>(</mo><mi>z</mi><mo>)</mo></mrow></mrow></math></span> and the kinetic energy <span><math><mfrac><mrow><msup><mrow><mover><mrow><mi>ϕ</mi></mrow><mrow><mo>̇</mo></mrow></mover></mrow><mrow><mn>2</mn></mrow></msup></mrow><mrow><mn>2</mn></mrow></mfrac></math></span> of the equivalent scalar field representing dark energy as functions of redshift <span><math><mi>z</mi></math></span>.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102462"},"PeriodicalIF":2.1,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144895110","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":"Unraveling the broadband spectrum of B2 1308+326: A clue to its high energy emission mechanism","authors":"Athar A. Dar ,&nbsp;Zahir Shah ,&nbsp;Sunder Sahayanathan ,&nbsp;Naseer Iqbal ,&nbsp;Subir Bhattacharyya ,&nbsp;Debanjan Bose","doi":"10.1016/j.newast.2025.102463","DOIUrl":"10.1016/j.newast.2025.102463","url":null,"abstract":"<div><div>The Flat Spectrum Radio Quasar (FSRQ) B2 1308+326 was in its highest <span><math><mi>γ</mi></math></span>-ray flaring state during 60260-60310 MJD. During this period, the source was detected in very high energy (VHE) by the large-sized telescope (LST-1). We conducted a detailed broadband spectral study of this source using the simultaneous data available in optical/UV, X-ray, and <span><math><mi>γ</mi></math></span>-ray bands. For the broadband spectral study, we select two gamma-ray high-flux states (59750-59800 MJD, 60260-60310 MJD) and one low-flux state (59250-59320 MJD). The broadband spectral energy distribution (SED) during these flux states are studied under leptonic emission scenario involving synchrotron, synchrotron self Compton (SSC) and external Compton (EC) processes. During the epochs, 59750-59800 MJD (high-flux state) and 59250-59320 MJD (low-flux state), the broadband SED is well fitted under the leptonic emission model while satisfying the equipartition between the particle and the magnetic field energy densities. However, the flaring state (60260-60310 MJD), during which the source showed VHE emission, demands deviation from equipartition by a factor of <span><math><mrow><mo>∼</mo><mn>14</mn></mrow></math></span> for the successful reproduction of the SED. This suggests the system may be under non-equilibrium condition or alternatively additional emission components may be active.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102463"},"PeriodicalIF":2.1,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144830950","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}