The Astrophysical Journal最新文献_第10页

Changing-look Active Galactic Nuclei: A Study of Optical/UV and the Highly Ionized Fe Kα X-Ray Line Flux Variations Using Photoionization Simulations 改变外观的活动星系核：利用光电离模拟研究光学/紫外和高电离Fe Kα x射线线通量变化

The Astrophysical Journal Pub Date : 2025-07-10 DOI: 10.3847/1538-4357/ade056

Tek P. Adhikari, Santanu Mondal, Zhicheng He, Agata Rozanska and Krzysztof Hryniewicz

{"title":"Changing-look Active Galactic Nuclei: A Study of Optical/UV and the Highly Ionized Fe Kα X-Ray Line Flux Variations Using Photoionization Simulations","authors":"Tek P. Adhikari, Santanu Mondal, Zhicheng He, Agata Rozanska and Krzysztof Hryniewicz","doi":"10.3847/1538-4357/ade056","DOIUrl":"https://doi.org/10.3847/1538-4357/ade056","url":null,"abstract":"Significant variability in broad emission line strengths of active galactic nuclei (AGN) over months to years has been observed, often accompanied by intrinsic continuum changes. Such spectral variability challenges the traditional AGN classification scheme, which attributes differences between type 1 and type 2 to geometrical effects, as transitions between these types occur on timescales shorter than viscous ones. In this work, using the cloudy photoionization simulations, we investigated the response of the major emission line fluxes, in the optical/UV and hard X-ray bands, to changes in the intensity and shape of the continuum emission of the AGN under two scenarios: (i) changes in the X-ray power law while keeping disk emission fixed, and (ii) broadband continuum variations. We demonstrate that broad-line region (BLR) line fluxes are insensitive to X-ray power-law changes alone. Considering a well-studied case of the changing-look (CL) AGN Mrk 1018, which exhibits variations in the intrinsic disk emission, as well as the X-ray power law, our simulations reproduce observed brightening and dimming trends of the BLR emission. Moreover, we show that the highly ionized Fe Kα X-ray flux, primarily produced by the H-like and He-like ions of Fe, strongly depends on the X-ray strength of the intrinsic spectral energy distribution. These findings suggest that the origin of highly ionized Fe Kα emission is in the coronal part of the accretion disk and that the CL phenomenon can be triggered by intrinsic changes in the accretion properties of AGN.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144603399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modeling of Two Low-amplitude Radially Pulsating δ Scuti Stars: KIC 12602250 and KIC 5768203 两颗低振幅径向脉动δ Scuti星：KIC 12602250和KIC 5768203的建模

The Astrophysical Journal Pub Date : 2025-07-10 DOI: 10.3847/1538-4357/add406

Shuguo Ma, A-Li Luo, Peng Wei, Chenglong Lv, Ming Yang, Fang Zuo, Yingzhen Cui, Shuo Li, Gang Meng, Wen Hou, Yuji He, Yinbi Li, Zhongyang Liu, Xiao-Xiao Ma, Jun-Chao Liang, Fei Dang, Daoye Yang, Ali Esamdin, Hao Zeng and Cai-Xia Qu

{"title":"Modeling of Two Low-amplitude Radially Pulsating δ Scuti Stars: KIC 12602250 and KIC 5768203","authors":"Shuguo Ma, A-Li Luo, Peng Wei, Chenglong Lv, Ming Yang, Fang Zuo, Yingzhen Cui, Shuo Li, Gang Meng, Wen Hou, Yuji He, Yinbi Li, Zhongyang Liu, Xiao-Xiao Ma, Jun-Chao Liang, Fei Dang, Daoye Yang, Ali Esamdin, Hao Zeng and Cai-Xia Qu","doi":"10.3847/1538-4357/add406","DOIUrl":"https://doi.org/10.3847/1538-4357/add406","url":null,"abstract":"In this research, we conducted systematic photometric, spectroscopic, and theoretical modeling analyses of two δ Scuti stars—KIC 12602250 and KIC 5768203—that pulsate only in radial modes. We collected their relevant photometric and spectroscopic parameters from multiple catalogs and estimated the absolute luminosities of both stars. Using high-precision time-series data from Kepler and TESS, we performed in-depth analysis of the periodic modulation in pulsation frequency phases, successfully determining the orbital periods and companion mass distribution ranges for these binary systems. Additionally, we thoroughly investigated the temporal evolution characteristics of pulsation periods and amplitudes. Based on calculations using Modules for Experiments in Stellar Astrophysics stellar evolution models, we determined that KIC 12602250 has a mass of with metallicity and is currently in the main-sequence evolutionary stage. For KIC 5768203, we derived precise parameters through rigorous constraints: mass M = 2.09 ± 0.01M⊙, metallicity Z = 0.024 ± 0.003, and radius R = 3.19 ± 0.01R⊙. Theoretical models reveal that this star has already crossed the first main-sequence turn-off point and entered the late-main-sequence evolutionary stage. Through comparative studies with typical High Amplitude δ Scuti stars, we believe that the primary reason for the low radial pulsation amplitudes in these two stars likely stems from their specific evolutionary states.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"106 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144603296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Counting the Unseen. II. Tidal Disruption Event Rates in Nearby Galaxies with REPTiDE 数着看不见的。2。邻近星系的潮汐破坏事件率与REPTiDE

The Astrophysical Journal Pub Date : 2025-07-10 DOI: 10.3847/1538-4357/addd1b

Christian H. Hannah, Nicholas C. Stone, Anil C. Seth and Sjoert van Velzen

{"title":"Counting the Unseen. II. Tidal Disruption Event Rates in Nearby Galaxies with REPTiDE","authors":"Christian H. Hannah, Nicholas C. Stone, Anil C. Seth and Sjoert van Velzen","doi":"10.3847/1538-4357/addd1b","DOIUrl":"https://doi.org/10.3847/1538-4357/addd1b","url":null,"abstract":"Tidal disruption events (TDEs) are a class of transients that occur when a star is destroyed by the tides of a massive black hole (MBH). Their rates encode valuable MBH demographic information, but this can only be extracted if accurate TDE rate predictions are available for comparisons with observed rates. In this work, we present a new, observer-friendly Python package called REPTiDE, which implements a standard loss-cone model for computing TDE rates given a stellar density distribution and an MBH mass. We apply this software to a representative sample of 91 nearby galaxies over a wide range of stellar masses with high-resolution nuclear density measurements from C. H. Hannah et al. We measure per-galaxy TDE rates ranging between 10−7.7 and 10−2.9 yr–1 and find that the sample-averaged rates agree well with observations. We find a turnover in the TDE rate as a function of both galaxy stellar mass and black hole mass, with the peak rates being observed in galaxies at a galaxy mass of 109.5M⊙ and a black hole mass of 106.5M⊙. Despite the lower TDE rates inferred for intermediate-mass black holes, we find that they have gained a higher fraction of their mass through TDEs when compared to higher-mass black holes. This growth of lower-mass black holes through TDEs can enable us to place interesting constraints on their spins; we find maximum spins of a• ≈ 0.9 for black holes with masses below ∼105.5M⊙.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"92 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spatially Resolved Modeling of Galactic Hα Emission for Galaxy Clustering 星系团中星系Hα发射的空间分辨模型

The Astrophysical Journal Pub Date : 2025-07-10 DOI: 10.3847/1538-4357/adde4c

Ivan Rapoport, Vincent Desjacques, Gabriele Parimbelli, Ehud Behar and Martin Crocce

{"title":"Spatially Resolved Modeling of Galactic Hα Emission for Galaxy Clustering","authors":"Ivan Rapoport, Vincent Desjacques, Gabriele Parimbelli, Ehud Behar and Martin Crocce","doi":"10.3847/1538-4357/adde4c","DOIUrl":"https://doi.org/10.3847/1538-4357/adde4c","url":null,"abstract":"Near-infrared spectroscopic surveys target high-redshift emission-line galaxies (ELGs) to probe cosmological scenarios. Understanding the clustering properties of ELGs is essential to derive optimal constraints. We present a simple radiative transfer model for spatially resolved galactic Hα emission, which includes emission from the warm-hot diffuse interstellar medium. The atomic-level populations are in steady state and computed in the coronal approximation. The model is applied to multiple IllustrisTNG simulations in the redshift range 1 ≤ z ≤ 2 to produce the luminosity function (LF) and the halo occupation distribution (HOD). Collisional processes account for a significant fraction (≈40%) of the total Hα luminosity (LHα). Our LFs are in reasonable agreement with measurements from Hα surveys if a uniform extinction of 0.3 < AHα < 0.85 mag is assumed. Our HOD is consistent with that of the Euclid Flagship galaxy mock up to differences that can be attributed to baryonic feedback, which is absent from the latter. When Hα luminosities are computed from an empirical relation between LHα and the total star formation rate, the resulting LFs are in tension with previous observations. Our approach can be extended to other atomic lines, which should be helpful for the mining of high-redshift galaxy spectra in forthcoming surveys.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144611193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of Deep Learning to the Classification of Stokes Profiles: From the Quiet Sun to Sunspots 深度学习在Stokes剖面分类中的应用：从安静的太阳到太阳黑子

The Astrophysical Journal Pub Date : 2025-07-09 DOI: 10.3847/1538-4357/addb49

Ryan J. Campbell, M. Mathioudakis, Carlos Quintero Noda, P. H. Keys and D. Orozco Suárez

{"title":"Application of Deep Learning to the Classification of Stokes Profiles: From the Quiet Sun to Sunspots","authors":"Ryan J. Campbell, M. Mathioudakis, Carlos Quintero Noda, P. H. Keys and D. Orozco Suárez","doi":"10.3847/1538-4357/addb49","DOIUrl":"https://doi.org/10.3847/1538-4357/addb49","url":null,"abstract":"The morphology of circular polarization profiles from solar spectropolarimetric observations encodes information about the magnetic field strength, inclination, and line-of-sight velocity gradients. Previous studies used manual methods or unsupervised machine learning (ML) to classify the shapes of circular polarization profiles. We trained a multilayer perceptron comparing classifications with unsupervised ML. The method was tested on quiet Sun data sets from Daniel K. Inouye Solar Telescope (DKIST), Hinode, and GREGOR, as well as simulations of granulation and a sunspot. We achieve validation metrics typically close to or above 90%. We also present the first statistical analysis of quiet Sun DKIST/ViSP data using inversions and our supervised classifier. We demonstrate that classifications with unsupervised ML alone can introduce systemic errors that could compromise statistical comparisons. DKIST and Hinode classifications in the quiet Sun are similar, despite our modeling indicating spatial resolution differences should alter the shapes of circular polarization signals. Asymmetrical (symmetrical) profiles are less (more) common in GREGOR than DKIST or Hinode data, consistent with narrower response functions in the 1564.85 nm line. Single-lobed profiles are extremely rare in GREGOR data. In the sunspot simulation, the 630.25 nm line produces “double” profiles in the penumbra, likely a manifestation of magneto-optical effects in horizontal fields; these are rarer in the 1564.85 nm line. We find the 1564.85 nm line detects more reverse polarity magnetic fields in the penumbra, in contradiction to observations. We detect mixed-polarity profiles in nearly one fifth of the penumbra. Supervised ML robustly classifies solar spectropolarimetric data, enabling detailed statistical analyses of magnetic fields.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"109 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144603405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Magnetic Field on the Accretion Phase of Population III Star Formation 磁场对星族III星形成吸积阶段的影响

The Astrophysical Journal Pub Date : 2025-07-09 DOI: 10.3847/1538-4357/addc56

Masahiro N. Machida, Shingo Hirano and Shantanu Basu

{"title":"Effect of Magnetic Field on the Accretion Phase of Population III Star Formation","authors":"Masahiro N. Machida, Shingo Hirano and Shantanu Basu","doi":"10.3847/1538-4357/addc56","DOIUrl":"https://doi.org/10.3847/1538-4357/addc56","url":null,"abstract":"We examine the impact of the magnetic field on Population III star formation by varying its strength. We perform simulations with magnetic field strengths ranging from 10−20 G to 10−4 G, in addition to a model without a magnetic field. The simulations are run for >1000–1400 yr after the first protostar forms. In weak-field models, the surrounding disk fragments, forming multiple protostars, and the magnetic field is amplified by the orbital motion and rotation of these protostars. In the model without a magnetic field, frequent fragmentation occurs, and the most massive protostar reaches ∼200 M⊙. However, in models with a magnetic field, once the magnetic field is amplified, the protostars merge to form a single massive protostar, and no further fragmentation occurs except in the model with the strongest magnetic field. Even after the formation of the single protostar, the magnetic field continues to amplify, leading to the formation of a thick disk supported by magnetic pressure and a global spiral pattern. In models with moderate or strong magnetic fields, a rotating disk can form, but fragmentation does not occur, and a strong magnetic field drives an outflow. However, the range of parameters for both disk formation and outflow driving is very narrow, making their appearance under realistic conditions unlikely. Given the weak magnetic field in the early Universe, Population III stars are expected to form as single stars, surrounded by a thick disk with a spiral pattern. Thus, the magnetic field, regardless of its strength, plays a crucial role in Population III star formation.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144593851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Convection Anisotropies of Cosmic Rays in Highly Magnetized Plasma 宇宙射线在高磁化等离子体中的对流各向异性

The Astrophysical Journal Pub Date : 2025-07-09 DOI: 10.3847/1538-4357/ade2d5

Yiran Zhang and Siming Liu

{"title":"Convection Anisotropies of Cosmic Rays in Highly Magnetized Plasma","authors":"Yiran Zhang and Siming Liu","doi":"10.3847/1538-4357/ade2d5","DOIUrl":"https://doi.org/10.3847/1538-4357/ade2d5","url":null,"abstract":"Recently, Y. Zhang & S. Liu proposed a turbulent convection model for multiscale anisotropies of cosmic rays (CRs), with an assumption of isotropic diffusion such that the anisotropies are statistically isotropic. However, this assumption may be unrealistic for TeV CRs, whose observations have revealed the significance of the local interstellar background magnetic field. To meet the difficulty, the turbulent convection scenario needs to be extended to cover anisotropic diffusion. In this paper, we focus on the parallel diffusion with isotropic pitch-angle scattering, which may be an approximation to the transport process driven by weak hydromagnetic waves in a magnetic flux tube, where fluctuations of the wave velocities lead to the turbulent convection. The consequence is the breaking of the statistical isotropy, while the overall shape of the angular power spectrum, (ℓ ≫ 1), remains similar to that in the isotropic diffusion model, where ℓ is degrees of spherical harmonics and γ is the turbulence spectral index of the convection field. It is then expected that the power-law index of the TeV CR small-scale angular power spectrum can be explained with the Kolmogorov law γ = 5/3, irrespective of the background magnetic field to some extent.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144593924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Cometary Fluorescence Model for the ν 3 Vibrational Band of Cyanogen 氰化物ν 3振动带的彗星荧光模型

The Astrophysical Journal Pub Date : 2025-07-09 DOI: 10.3847/1538-4357/addf3e

P. Hardy, P. Rousselot, C. Richard, V. Boudon, X. Landsheere, A. Voute, L. Manceron and F. Kwabia Tchana

引用次数: 0

The Dust Extinction Curve: Beyond R(V) 尘埃消退曲线：超过R(V)

The Astrophysical Journal Pub Date : 2025-07-09 DOI: 10.3847/1538-4357/addd11

Gregory M. Green, Xiangyu Zhang, 翔宇张, Ruoyi Zhang and 若羿张

{"title":"The Dust Extinction Curve: Beyond R(V)","authors":"Gregory M. Green, Xiangyu Zhang, 翔宇张, Ruoyi Zhang and 若羿张","doi":"10.3847/1538-4357/addd11","DOIUrl":"https://doi.org/10.3847/1538-4357/addd11","url":null,"abstract":"The dust extinction curve is typically parameterized by a single variable, R(V), in optical and near-infrared wavelengths. R(V) controls the slope of the extinction-versus-wavelength curve, and is thought to reflect the grain-size distribution and composition of dust. Low-resolution, flux-calibrated BP/RP spectra from Gaia have allowed the determination of the extinction curve along sightlines to 130 million stars in the Milky Way and Magellanic Clouds. We show that these extinction curves contain more than a single degree of freedom—that is, that they are not simply described by R(V). We identify a number of components that are orthogonal to R(V) variation, and we show that these components vary across the sky in coherent patterns that resemble interstellar medium (ISM) structure. These components encode variation in the 770 nm extinction feature, intermediate-scale and very broad structure, and a newly identified feature at 850 nm, and they likely trace both dust composition and local conditions in the ISM. Correlations of the 770 and 850 nm features with R(V) suggest that their carriers become more abundant as the carrier of the 2175 Å feature is destroyed. Our 24 million extinction-curve decompositions and feature equivalent-width measurements are publicly available at doi:10.5281/zenodo.14005028.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144603302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Milky Way Radial Metallicity Gradient as an Equilibrium Phenomenon: Why Old Stars Are Metal Rich 银河系径向金属丰度梯度作为一种平衡现象：为什么老恒星富含金属

The Astrophysical Journal Pub Date : 2025-07-09 DOI: 10.3847/1538-4357/addbe5

James W. Johnson, David H. Weinberg, Guillermo A. Blanc, Ana Bonaca, Gwen C. Rudie, Yuxi (Lucy) Lu, Bronwyn Reichardt Chu, Emily J. Griffith, Tawny Sit, Jennifer A. Johnson, Liam O. Dubay, Miqaela K. Weller, Daniel A. Boyea and Jonathan C. Bird

{"title":"The Milky Way Radial Metallicity Gradient as an Equilibrium Phenomenon: Why Old Stars Are Metal Rich","authors":"James W. Johnson, David H. Weinberg, Guillermo A. Blanc, Ana Bonaca, Gwen C. Rudie, Yuxi (Lucy) Lu, Bronwyn Reichardt Chu, Emily J. Griffith, Tawny Sit, Jennifer A. Johnson, Liam O. Dubay, Miqaela K. Weller, Daniel A. Boyea and Jonathan C. Bird","doi":"10.3847/1538-4357/addbe5","DOIUrl":"https://doi.org/10.3847/1538-4357/addbe5","url":null,"abstract":"Metallicities of both gas and stars decline toward large radii in spiral galaxies, a trend known as the radial metallicity gradient. We quantify the evolution of the metallicity gradient in the Milky Way as traced by APOGEE red giants with age estimates from machine learning algorithms. Stars up to ages of ∼9 Gyr follow a similar relation between metallicity and Galactocentric radius. This constancy challenges current models of Galactic chemical evolution, which typically predict lower metallicities for older stellar populations. Our results favor an equilibrium scenario, in which the gas-phase gradient reaches a nearly constant normalization early in the disk lifetime. Using a fiducial choice of parameters, we demonstrate that one possible origin of this behavior is an outflow that more readily ejects gas from the interstellar medium (ISM) with increasing Galactocentric radius. A direct effect of the outflow is that baryons do not remain in the ISM for long, which causes the ratio of star formation to accretion, , to quickly become constant. This ratio is closely related to the local equilibrium metallicity, since its numerator and denominator set the rates of metal production by stars and hydrogen gained through accretion, respectively. Building in a merger event results in a perturbation that evolves back toward the equilibrium state on ∼Gyr timescales. Under the equilibrium scenario, the radial metallicity gradient is not a consequence of the inside-out growth of the disk but instead reflects a trend of declining with increasing Galactocentric radius.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144593922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0