New Astronomy最新文献_第2页

Insights on gas distribution and dynamics in massive proto-cluster G358.46−0.39: Possible multiplicity in G358.46−0.39 MM1a 关于G358.46 - 0.39大质量原星团中气体分布和动力学的见解：G358.46 - 0.39 MM1a中可能存在的多样性

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-18 DOI: 10.1016/j.newast.2025.102498

Chukwuebuka J. Ugwu , James O. Chibueze , Willice O. Obonyo , Mavis Seidu

This work explored the spatial distribution of C¹⁷O, SiO, HC₃N and SO₂ molecules, as well as the energetics of outflows in G358.46

-

0.39 proto-cluster using ALMA band 7 archival data, with the aim of providing an improved understanding of its protostellar nature, gas kinematics and dynamics. G358.46

-

0.39 is previously known to consist of 4 dust continuum cores (MM1a, MM1b, MM1c and MM2). The integrated intensity map of C¹⁷O reveals filamentary and dumbbell-shaped structures that are probably compressed gases from the expansion of the HII region MM2. The SiO emission reveals spatially overlapped blue and red outflow lobes, likely driven by an unresolved young stellar object (YSO) in MM1a. The spatial distribution of HC₃N and SO₂ molecules in MM1a shows a compact morphology, with no detectable HC₃N and SO₂ emissions in the other cores. The SO₂ emission reveals a clear velocity gradient in MM1a, as well as large velocity dispersion (

\sim

3 km s

^{- 1}

) within the inner core of MM1a, which are consistent with rotating structures. We estimated the mass, momentum and energy outflow rate, as well as other outflow parameters. The SiO outflow exhibits a different morphology compared to the ¹²CO outflow morphology previously observed in MM1a. The SiO and ¹²CO outflows are probably associated with disks of separate cores with one face-on and the other edge-on, pointing to multiplicity of YSOs in MM1a. The properties of MM1a indicate that it is a massive protostar that is actively accreting and undergoing star formation.

本研究利用ALMA波段7档案数据，探索了G358.46−0.39原星团中C17O、SiO、HC3N和SO2分子的空间分布，以及流出物的能量学，旨在更好地了解其原恒星性质、气体运动学和动力学。G358.46−0.39先前已知由4个尘埃连续体核心（MM1a, MM1b， MM1c和MM2）组成。C17O的综合强度图显示了丝状和哑铃状结构，可能是HII区域MM2膨胀产生的压缩气体。SiO发射显示空间上重叠的蓝色和红色流出叶，可能是由MM1a中未解析的年轻恒星物体（YSO）驱动的。MM1a中HC3N和SO2分子的空间分布表现为致密的形态，其他核芯中没有检测到HC3N和SO2的排放。SO2发射在MM1a中显示出明显的速度梯度，以及在MM1a内核内的大速度色散（~ 3 km s−1），这与旋转结构一致。我们估计了质量、动量和能量流出率以及其他流出参数。与先前在MM1a中观察到的12CO流出形态相比，SiO流出表现出不同的形态。SiO和12CO的流出可能与单独核的磁盘有关，一个面朝上，另一个面朝上，这表明MM1a中存在多个yso。MM1a的特性表明它是一颗大质量原恒星，正在活跃地吸积和形成恒星。

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引用次数: 0

Absolute parameters of the southern detached eclipsing binary DG Mic 南离食双星DG - Mic的绝对参数

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-11 DOI: 10.1016/j.newast.2025.102496

Derya Sürgit , Mücahit Kuz , Volkan Bakış , Chris Engelbrecht , Fred Marang

As part of an ongoing programme of observing detached eclipsing binary stars in the southern sky, we present the first analysis of spectroscopic observations of the Algol-type binary system DG Mic. A spectroscopic analysis of mid-resolution spectra allowed us to constrain the effective temperature of the primary component and to test the consistency of the system parameters with its spectral energy distribution (SED). Combined solutions of mid-resolution spectra and TESS, ASAS and WASP light curves imply a system of two almost identical components (

q

= 0.99) in circular orbits. Our final model shows that the system is a detached binary star. The masses and radii of the primary and secondary components of DG Mic were derived to be 1.65(

\pm

0.12) M

_{⊙}

, 1.64(

\pm

0.18) M

_{⊙}

and 1.63(

\pm

0.10) R

_{⊙}

, 1.91(

\pm

0.13) R

_{⊙}

, respectively. According to Geneva evolution models, both components of the system are main-sequence stars and their age is approximately 713 Myr.

作为正在进行的观测南方天空中分离的食双星计划的一部分，我们提出了对algol型双星系统DG - Mic的光谱观测的第一次分析。对中分辨率光谱的光谱分析使我们能够约束主组分的有效温度，并测试系统参数与其光谱能量分布（SED）的一致性。中分辨率光谱与TESS、ASAS和WASP光曲线的综合解表明，在圆形轨道上，两个组分几乎相同（q = 0.99）。我们的最终模型表明该系统是一颗分离的双星。DG Mic主、次组分的质量和半径分别为1.65（±0.12）M⊙、1.64（±0.18）M⊙和1.63（±0.10）R⊙、1.91（±0.13）R⊙。根据日内瓦演化模型，该系统的两个组成部分都是主序星，它们的年龄大约是713亿万年。

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引用次数: 0

Low-frequency observations of low-mass binary systems with neutron star candidates 中子星候选低质量双星系统的低频观测

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-11 DOI: 10.1016/j.newast.2025.102500

Elena Brylyakova , Marina Afonina , Gayane Tyul’basheva , Sergei B. Popov , Sergei Tyul’bashev

Recently, astrometric and spectroscopic observations resulted in the discovery of several low-mass binaries with invisible components, which are expected to be compact objects. In about two dozen cases, the masses of these components are consistent with neutron stars. We use low-frequency archival data obtained with the Large Phased Array in Pushchino to search for radio emission from five of these systems. For all the systems, we do not detect persistent or periodic emission. In one case (2MASS J1527+3536), we identify a single radio burst with a flux of 13 Jy and a duration of 0.13 s. However, the dispersion measure of the burst does not correspond to an expected value for the source. We discuss several possibilities to explain the properties of this burst.

最近，天文测量和光谱观测发现了几个具有不可见成分的低质量双星，它们被认为是致密天体。在大约24种情况下，这些成分的质量与中子星一致。我们使用普什奇诺大型相控阵获得的低频档案数据来搜索其中五个系统的无线电发射。对于所有的系统，我们没有检测到持续的或周期性的发射。在其中一个例子（2MASS J1527+3536）中，我们发现了一个单一的射电暴，其通量为13焦耳，持续时间为0.13秒。然而，爆发的色散测量值并不对应于源的期望值。我们讨论了几种解释这种爆发性质的可能性。

引用次数: 0

Stellar kinematics of the Milky Way Galaxy in post-Newtonian gravity 后牛顿引力下银河系的恒星运动学

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-09 DOI: 10.1016/j.newast.2025.102499

Shubhen BISWAS

The recent Gaia data confirm that the Milky Way’s outer stellar disk shows a tangible Keplerian decline in rotation curve. The data also reveal that the stellar velocity maintains a positive correlation with the surface gravity. These revelations present scope for revisiting our understanding of galactic stellar dynamics. Herein, we use the recent interaction model over the post-Newtonian theory of gravity to study celestial dynamics considering the stellar body as an extended object rather than a point particle in space. By jointly considering the central super massive black hole and galactic stellar disk, a rotating stellar body around this combination is theoretically modeled as a two-body system. The model predicts a galactocentric solar rotational speed of

226 km . s^{- 1}

for the Milky Way, consistent with the observations.

Classification codes: 04.00; 95.10.Ce

最近的盖亚数据证实，银河系的外星盘显示出明显的开普勒衰减旋转曲线。数据还显示，恒星速度与表面重力保持正相关。这些发现为重新审视我们对银河系恒星动力学的理解提供了空间。在此，我们使用基于后牛顿引力理论的最新相互作用模型来研究天体动力学，将恒星体视为扩展物体而不是空间中的点粒子。通过共同考虑中央超大质量黑洞和星系恒星盘，围绕这一组合旋转的恒星体在理论上被建模为一个两体系统。该模型预测银河系以星系为中心的太阳自转速度为226公里/秒，与观测结果一致。分类代码：04.00；95.10.Ce

引用次数: 0

Probing dust and PAH chemistry in evolved carbon-rich nebulae through optical and infrared observations 通过光学和红外观测在演化的富碳星云中探测尘埃和多环芳烃化学

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-07 DOI: 10.1016/j.newast.2025.102494

Rahul Kumar Anand , Atul Kumar Singh , Saurabh Sharma , Brijesh Kumar , Shantanu Rastogi

This study presents optical and near-infrared photometric observations, alongside mid-infrared spectroscopic data from the ISO SWS instrument, to examine potential correlations between Aromatic Infrared Band (AIB) features and the optical properties of carbon-rich evolved stars. Identifying such correlations can provide valuable constraints on the evolutionary pathways of low- to intermediate-mass stars beyond the asymptotic giant branch (AGB) phase. Photometric measurements in the U, B, V, R, I, J, H, K, and L bands were obtained for five well-known carbon-rich objects at various post-AGB or planetary nebula (PN) stages: CRL 2688, PN M 2-43, NGC 7027, BD

+ 3 0^{\circ}

3639, and AFGL 2132. Our analysis reveals that all five objects exhibit prominent AIB features; however, their spectral profiles show notable variation. These differences are attributed to variations in the chemical composition and physical conditions of the surrounding circumstellar material. In particular, the

3.28 μ m

polycyclic aromatic hydrocarbon (PAH) feature is detected in all objects except AFGL 2132, indicating a potentially distinct PAH population or environmental condition in its vicinity. Although these sources share broadly similar evolutionary stages, the observed diversity in AIB characteristics underscores the complexity and heterogeneity of their circumstellar environments.

本研究提出了光学和近红外光度观测，以及来自ISO SWS仪器的中红外光谱数据，以研究芳香红外波段（AIB）特征与富碳演化恒星光学特性之间的潜在相关性。确定这种相关性可以为中低质恒星在渐近巨支（AGB）阶段以外的演化路径提供有价值的约束。在U、B、V、R、I、J、H、K和L波段测量了5个著名的富碳天体在agb后或行星状星云（PN）的不同阶段：CRL 2688、PN m2 -43、NGC 7027、BD+30°3639和AFGL 2132。我们的分析表明，这五个物体都表现出明显的AIB特征；然而，它们的光谱分布有显著的变化。这些差异归因于周围星周物质的化学成分和物理条件的变化。除AFGL 2132外，所有目标均检测到3.28μm的多环芳烃（PAH）特征，表明其附近可能存在明显的PAH种群或环境状况。尽管这些来源具有大致相似的进化阶段，但观察到的AIB特征的多样性强调了其星周环境的复杂性和异质性。

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引用次数: 0

Statistical analysis of eclipsing binaries with monotonic orbital-period variations: A-type W UMa contact systems 轨道周期单调变化的食双星的统计分析：a型wuma接触系统

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-07 DOI: 10.1016/j.newast.2025.102495

Shinjirou Kouzuma

On the basis of monotonic orbital-period variations, this study aims to identify genuine relationships between binary parameters and the rates of mass transfer (MT), mass loss (ML), and angular momentum loss (AML). Sample binaries with monotonic period variations are collected from the literature, together with well-determined binary parameters. Assuming the monotonic variations are responsible for any one of the MT, ML, and AML, their rates are calculated with the rates of change of period. After selecting crucial parameters using partial least-squares analysis, a parameter that exhibits the closest correlation with any one of the derived rates is further selected using partial regression plots. Moreover, power-law relationships are found for the discovered correlations. The properties of the sample binaries are also investigated by examining associations between binary parameters. In the systems with negative period variations, it is found that the rate of MT from more- to less-massive stars is a function of the primary radius; the AML rate is a function of the fill-out factor. In addition, the relationships between the mass ratio and stellar masses indicate that the ML rate relative to the MT rate decreases with increasing mass ratio below

\sim 0.46

. Meanwhile, in the systems with positive variations, it is found that the rate of MT from less- to more-massive stars is a function of the luminosity ratio and/or mass ratio; the ML rate is a function of the secondary temperature. The discussion also addresses possible processes occurring in the sample binaries.

在单调轨道周期变化的基础上，本研究旨在确定二元参数与传质速率（MT）、质量损失（ML）和角动量损失（AML）之间的真实关系。从文献中收集了具有单调周期变化的二进制样本，以及确定的二进制参数。假设单调变化负责MT， ML和AML中的任何一个，它们的速率是用周期变化率计算的。在使用偏最小二乘分析选择关键参数之后，使用偏回归图进一步选择与任何一个派生率表现出最密切相关性的参数。此外，发现的相关性发现幂律关系。通过检查二进制参数之间的关联，还研究了样本二进制的性质。在具有负周期变化的星系中，发现大质量恒星到小质量恒星的MT速率是主恒星半径的函数；AML率是填写因子的函数。此外，质量比与恒星质量之间的关系表明，相对于MT率的ML率在0.46以下随质量比的增加而降低。同时，在正变化的系统中，发现从小质量恒星到大质量恒星的MT率是光度比和（或）质量比的函数；ML速率是二次温度的函数。本文还讨论了示例二进制文件中可能发生的过程。

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引用次数: 0

Cosmological dynamics of barrow holographic dark energy in f(G) gravity: An analytical and observational approach 巴罗全息暗能量在f(G)引力中的宇宙学动力学：一种分析和观测方法

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-05 DOI: 10.1016/j.newast.2025.102497

A.Y. Shaikh , A.P. Jenekar

The presented study prioritizes the exploration of the cosmic model that integrates Barrow holographic dark energy (BHDE) within the confines of

f (G)

gravity. The study proposes to resolve the field equations of the cosmic model by incorporating the temporal deceleration parameter (DP) in relation to the scale factor. We assessed the model's predictability using a Bayesian MCMC approach that draws on late-time cosmic observations, comprising 58 data values, and the SN Ia pantheon datasets involving 1048 data values, along with their combination, to set bounds around the free parameters. The Hubble threshold applies as an infrared (IR) threshold in the inspection of the BHDE. We thoroughly study the kinematical and physical aspects of the model. Our findings establish a seamless advance of the cosmos, moving from a decelerating era in earlier times to an accelerating era in both the immediate as well as distant future, as revealed by the trajectories of the equation of state

(ω_{b})

, deceleration

(q)

, jerk

(j)

, snap

(s)

, and lerk

(l)

parameters. We investigate the phase diagnostics via statefinder and

O m (z)

analysis. The insight of energy conditions (ECs) further substantiates the predominance of BHDE following a speeding up Universe, while the model’s stability is predicted by the parameter of squared speed of sound. We concluded that our study's results comply with existing observational evidence, proving that our model demonstrates an effective alternative interpretation for the Universe's observed acceleration by accurately capturing the emergence of energy components while preserving stability.

提出的研究优先探索宇宙模型，将巴罗全息暗能量（BHDE）整合在f(G)引力范围内。本研究提出将时间减速参数（DP）与尺度因子相结合，求解宇宙模型的场方程。我们使用贝叶斯MCMC方法评估了模型的可预测性，该方法利用了包含58个数据值的晚期宇宙观测数据集和包含1048个数据值的SN Ia万神殿数据集，以及它们的组合，以设置自由参数周围的边界。哈勃阈值适用于BHDE的红外（IR）阈值检测。我们深入研究了模型的运动学和物理方面。我们的发现建立了宇宙的无缝推进，从早期的减速时代到当前和遥远未来的加速时代，正如状态方程（ωb），减速(q), jerk (j), snap (s)和lerk (l)参数的轨迹所揭示的那样。我们通过状态检测器和Om(z)分析研究了相位诊断。能量条件（ECs）的洞察进一步证实了宇宙加速后BHDE的优势，而该模型的稳定性由声速的平方参数预测。我们的结论是，我们的研究结果符合现有的观测证据，证明我们的模型通过准确地捕捉能量成分的出现，同时保持稳定性，为观测到的宇宙加速度提供了有效的替代解释。

{"title":"Cosmological dynamics of barrow holographic dark energy in f(G) gravity: An analytical and observational approach","authors":"A.Y. Shaikh , A.P. Jenekar","doi":"10.1016/j.newast.2025.102497","DOIUrl":"10.1016/j.newast.2025.102497","url":null,"abstract":"<div><div>The presented study prioritizes the exploration of the cosmic model that integrates Barrow holographic dark energy (BHDE) within the confines of <span><math><mrow><mi>f</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow></math></span> gravity. The study proposes to resolve the field equations of the cosmic model by incorporating the temporal deceleration parameter (DP) in relation to the scale factor. We assessed the model's predictability using a Bayesian MCMC approach that draws on late-time cosmic observations, comprising 58 data values, and the SN Ia pantheon datasets involving 1048 data values, along with their combination, to set bounds around the free parameters. The Hubble threshold applies as an infrared (IR) threshold in the inspection of the BHDE. We thoroughly study the kinematical and physical aspects of the model. Our findings establish a seamless advance of the cosmos, moving from a decelerating era in earlier times to an accelerating era in both the immediate as well as distant future, as revealed by the trajectories of the equation of state <span><math><mrow><mo>(</mo><msub><mi>ω</mi><mi>b</mi></msub><mo>)</mo></mrow></math></span>, deceleration <span><math><mrow><mo>(</mo><mi>q</mi><mo>)</mo></mrow></math></span>, jerk <span><math><mrow><mo>(</mo><mi>j</mi><mo>)</mo></mrow></math></span>, snap <span><math><mrow><mo>(</mo><mi>s</mi><mo>)</mo></mrow></math></span>, and lerk <span><math><mrow><mo>(</mo><mi>l</mi><mo>)</mo></mrow></math></span> parameters. We investigate the phase diagnostics via statefinder and <span><math><mrow><mi>O</mi><mi>m</mi><mo>(</mo><mi>z</mi><mo>)</mo></mrow></math></span> analysis. The insight of energy conditions (ECs) further substantiates the predominance of BHDE following a speeding up Universe, while the model’s stability is predicted by the parameter of squared speed of sound. We concluded that our study's results comply with existing observational evidence, proving that our model demonstrates an effective alternative interpretation for the Universe's observed acceleration by accurately capturing the emergence of energy components while preserving stability.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"123 ","pages":"Article 102497"},"PeriodicalIF":2.1,"publicationDate":"2025-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145520882","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}

引用次数: 0

Investigating star formation scenarios in the Milky Way using YSO distributions—A pilot study 利用YSO分布研究银河系中恒星形成的场景——一项初步研究

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-04 DOI: 10.1016/j.newast.2025.102482

Annarien G. Headley , James O. Chibueze

We investigated the distributions of classified young stellar object (YSO) in nine star-forming regions associated with Hii regions, namely Sh2-22, Sh2-19, Sh2-17, M16, M8, IC5070, Sh2-252, NGC2467 and M42, as a means of exploring the star formation scenarios (triggered or spontaneous) in the various regions. The YSO distributions of nine regions along the galactic longitudes and across different spiral arms were explored. It is noted that Sh2-22 and Sh2-19 may have evidence of localized triggered star formation, whereas Sh2-17 may be a spontaneous star forming region. The results showed that the location within the Milky Way may influence localized triggered star formation within individual regions. There is strong evidence that there are fewer older stars (Transition Disks) within the Outer regions of the Galaxy (

2.91 \pm 1.74 %

), accompanied by a higher number of Class I (

32.49 \pm 10.77 %

). This is different from the Inner Galactic regions where the Transition Disks are higher (

32.93 \pm 13.78 %

) as compared to low Class I sources (

11.01 \pm 4.81 %

). The number of Class II stars is relatively high and increases from the Inner regions (

52.64 \pm 10.07 %

) to Outer regions (

64.54 \pm 11.09 %

). These nine star-forming regions are not an accurate representation of locations throughout the Galaxy and the results may be biased.

我们研究了与Hii区域相关的9个恒星形成区域（即Sh2-22、Sh2-19、Sh2-17、M16、M8、IC5070、Sh2-252、NGC2467和M42）中分类年轻恒星天体（YSO）的分布，以探索不同区域的恒星形成情景（触发或自发）。探索了沿银河系经度和不同旋臂的9个区域的YSO分布。值得注意的是，Sh2-22和Sh2-19可能有局部触发恒星形成的证据，而Sh2-17可能是一个自发的恒星形成区。结果表明，银河系内的位置可能会影响单个区域内局部触发的恒星形成。有强有力的证据表明，银河系外围区域的老恒星（过渡盘）较少（2.91±1.74%），而I类恒星数量较多（32.49±10.77%）。这与内银河区域不同，内银河区域的过渡盘比低I类源（11.01±4.81%）高（32.93±13.78%）。II类恒星数量相对较多，由内区（52.64±10.07%）向外区（64.54±11.09%）增加。这九个恒星形成区域并不能准确地代表整个银河系的位置，结果可能会有偏差。

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引用次数: 0

Gravitational instability in Plummer sphere profile: A Jeans analysis 普卢默球剖面的引力不稳定性：一个Jeans的分析

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-01 DOI: 10.1016/j.newast.2025.102493

Abdelhakim Benkrane

We investigate the gravitational instability of self-gravitating systems characterized by the Plummer sphere profile. Using Jeans analysis, we derive modified expressions for the Jeans mass and Jeans radius, revealing that the presence of the Plummer radius

r_{0}

increases both critical parameters, thereby suppressing gravitational collapse. In the classical regime, we obtain a modified dispersion relation incorporating the Fourier transform of the Plummer potential. Our results show that

r_{0}

reduces the growth rate of perturbations and shifts the critical wavenumber to lower values, favoring the development of instability at longer wavelengths. We also extend the analysis to the quantum regime, where quantum pressure introduces a stabilizing

k^{4}

-term in the dispersion relation. We find that at large wave numbers, quantum effects dominate and the influence of the

r_{0}

becomes negligible. These findings highlight the role of Plummer sphere profile in modulating the onset and scale of gravitational collapse, with implications for star formation and structure formation in dark matter (DM)-rich environments.

我们研究了以Plummer球剖面为特征的自重力系统的引力不稳定性。利用Jeans分析，我们得到了Jeans质量和Jeans半径的修正表达式，揭示了Plummer半径r0的存在增加了这两个关键参数，从而抑制了引力坍缩。在经典状态下，我们得到了包含Plummer势的傅里叶变换的修正色散关系。我们的研究结果表明，r0降低了扰动的增长率，并将临界波数移到更低的值，有利于在更长的波长上发展不稳定性。我们还将分析扩展到量子状态，其中量子压力在色散关系中引入了一个稳定的k4项。我们发现，在大波数下，量子效应占主导地位，r0的影响可以忽略不计。这些发现突出了普卢默球剖面在调节引力坍缩的开始和规模方面的作用，对暗物质（DM）丰富环境中的恒星形成和结构形成具有启示意义。

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引用次数: 0

Calibrating machine learning with multi-band photometry: Resolving parameter degeneracies in contact binary NSVS 4803568 用多波段光度法校准机器学习：解决接触二元nsvs4803568的参数简并

IF 2.1 4区物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS

New Astronomy

Pub Date : 2025-11-01 DOI: 10.1016/j.newast.2025.102484

Xu-Zhi Li , Xue-Tong Liu , Wei Liu , Xu-Dong Zhang

Contact binary stars are crucial for studying stellar evolution and merger events, but precise determination of their physical parameters (mass ratio

q

, inclination

i

, fill-out factor

f

) is challenging. While large-scale, single-band surveys coupled with machine learning enable rapid population studies, discrepancies arise between solutions derived from such automated pipelines due to inherent degeneracies and limited wavelength constraints. In this work, we resolve the conflicting parameters reported for contact binary system NSVS 4803568 through comprehensive multi-band photometric observations. We conducted follow-up

B

,

V

,

R

, and

I

-band observations and analyzed the light curves using PHOEBE, refined via Markov Chain Monte Carlo. Our solution confirms the system as a W-subtype contact binary and reveals a significant third-light contribution. The parameter inconsistencies between single-band studies highlight limitations in machine learning training data sensitivity and the need for multi-dimensional flux constraints. We advocate a hybrid approach: machine learning pre-screening of survey data to identify high-priority targets (e.g., extreme

q

or short period systems) followed by multi-band validation to calibrate models and mitigate systematic errors. This synergy is essential for unlocking the full potential of astronomical big data in stellar astrophysics.

接触双星对于研究恒星演化和合并事件至关重要，但精确确定它们的物理参数（质量比q，倾角i，填充因子f）是具有挑战性的。虽然大规模的单波段调查与机器学习相结合可以实现快速的人口研究，但由于固有的简并性和有限的波长限制，从这种自动化管道中得出的解决方案之间存在差异。本文通过综合多波段光度观测，解决了接触双星nsv 4803568中存在的参数冲突问题。我们进行了后续的B、V、R和i波段观测，并使用通过马尔科夫链蒙特卡罗改进的PHOEBE分析了光曲线。我们的解决方案证实了该系统是w亚型接触双星，并揭示了重要的第三光贡献。单波段研究之间的参数不一致突出了机器学习训练数据敏感性的局限性以及对多维通量约束的需求。我们提倡一种混合方法：机器学习预先筛选调查数据以确定高优先级目标（例如，极端q或短周期系统），然后进行多波段验证以校准模型并减轻系统误差。这种协同作用对于释放恒星天体物理学中天文大数据的全部潜力至关重要。

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引用次数: 0