Pub Date : 2025-01-08DOI: 10.1051/0004-6361/202452752
Si-Yue Yu, Dewang Xu, Boris S. Kalita, Sijia Li, John D. Silverman, Xinyue Liang, Taotao Fang
We investigate the deconvolved color profiles of 223 disk galaxies at redshifts of z = 1–3 observed by the James Webb Space Telescope (JWST) as part of the Cosmic Evolution Early Release Science survey (CEERS). The filters were selected to approximate the rest-frame B − Y color, which is used to identify U-shaped color profiles –those becoming progressively bluer with increasing radius, then turning redder beyond a specific point. We find that 36% of Type II (down-bending) disks exhibit U-shaped color profiles with a minimum at or near the disk break. In contrast, no Type I (single-exponential) disks and only 9% of Type III (up-bending) disks show such a profile. The presence of U-shaped color profiles in Type II disks likely arises from the interplay between a star-formation threshold and spiral- or bar-driven secular radial migration of older stars outward. The fraction of Type II disks exhibiting a U-shaped color profile remains almost consistent across two redshift bins, z = 1–2 and z = 2–3, but is significantly lower than that observed in the local Universe, likely because the secular process of radial migration at high redshift may not have had sufficient time to significantly influence the disk structure. The absence of U-shaped color profiles in Type II disks could point to rapid rather than secular radial star migration potentially caused by violent clump instabilities, transporting both younger and older stars to the outer disk. Our results provide useful constraints on the formation and evolution models of disk galaxies in the early Universe.
{"title":"Color profiles of disk galaxies at z = 1–3 observed with JWST: Implications for outer-disk formation histories","authors":"Si-Yue Yu, Dewang Xu, Boris S. Kalita, Sijia Li, John D. Silverman, Xinyue Liang, Taotao Fang","doi":"10.1051/0004-6361/202452752","DOIUrl":"https://doi.org/10.1051/0004-6361/202452752","url":null,"abstract":"We investigate the deconvolved color profiles of 223 disk galaxies at redshifts of <i>z<i/> = 1–3 observed by the James Webb Space Telescope (JWST) as part of the Cosmic Evolution Early Release Science survey (CEERS). The filters were selected to approximate the rest-frame <i>B<i/> − <i>Y<i/> color, which is used to identify U-shaped color profiles –those becoming progressively bluer with increasing radius, then turning redder beyond a specific point. We find that 36% of Type II (down-bending) disks exhibit U-shaped color profiles with a minimum at or near the disk break. In contrast, no Type I (single-exponential) disks and only 9% of Type III (up-bending) disks show such a profile. The presence of U-shaped color profiles in Type II disks likely arises from the interplay between a star-formation threshold and spiral- or bar-driven secular radial migration of older stars outward. The fraction of Type II disks exhibiting a U-shaped color profile remains almost consistent across two redshift bins, <i>z<i/> = 1–2 and <i>z<i/> = 2–3, but is significantly lower than that observed in the local Universe, likely because the secular process of radial migration at high redshift may not have had sufficient time to significantly influence the disk structure. The absence of U-shaped color profiles in Type II disks could point to rapid rather than secular radial star migration potentially caused by violent clump instabilities, transporting both younger and older stars to the outer disk. Our results provide useful constraints on the formation and evolution models of disk galaxies in the early Universe.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"23 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-07DOI: 10.1051/0004-6361/202451679
S. Véliz Astudillo, E. R. Carrasco, J. L. Nilo Castellón, A. Zenteno, H. Cuevas
Context. Although the influence of galaxy clusters on galaxy evolution is relatively well understood, the impact of the dynamical states of these clusters is less clear. This series of papers explores how the dynamical state of galaxy clusters affects their galaxy populations’ physical and morphological properties.Aims. The primary aim of this first paper is to evaluate the dynamical state of 87 massive (M500 ≥ 1.5 × 1014M⊙) galaxy clusters at low redshifts (0.10 ≤ z ≤ 0.35). This allowed us to obtain a well-characterized sample for analyzing the relevant physical and morphological properties, planned for our next work.Methods. We employed six dynamical state proxies that utilize optical and X-ray imaging data. We applied a principal component analysis to integrate these proxies effectively, allowing for a robust classification of galaxy clusters into relaxed, intermediate, and disturbed states based on their dynamical characteristics.Results. The methodology successfully segregates the clusters of galaxies into the three dynamical states. An examination of the projected galaxy distributions in optical wavelengths and gas distributions in X-ray further confirms the consistency of these classifications. The dynamical states of the clusters are statistically distinguishable, providing a clear categorization for further analysis.
{"title":"The effect of dynamical states on galaxy cluster populations","authors":"S. Véliz Astudillo, E. R. Carrasco, J. L. Nilo Castellón, A. Zenteno, H. Cuevas","doi":"10.1051/0004-6361/202451679","DOIUrl":"https://doi.org/10.1051/0004-6361/202451679","url":null,"abstract":"<i>Context.<i/> Although the influence of galaxy clusters on galaxy evolution is relatively well understood, the impact of the dynamical states of these clusters is less clear. This series of papers explores how the dynamical state of galaxy clusters affects their galaxy populations’ physical and morphological properties.<i>Aims.<i/> The primary aim of this first paper is to evaluate the dynamical state of 87 massive (<i>M<i/><sub>500<sub/> ≥ 1.5 × 10<sup>14<sup/> <i>M<i/><sub>⊙<sub/>) galaxy clusters at low redshifts (0.10 ≤ <i>z<i/> ≤ 0.35). This allowed us to obtain a well-characterized sample for analyzing the relevant physical and morphological properties, planned for our next work.<i>Methods.<i/> We employed six dynamical state proxies that utilize optical and X-ray imaging data. We applied a principal component analysis to integrate these proxies effectively, allowing for a robust classification of galaxy clusters into relaxed, intermediate, and disturbed states based on their dynamical characteristics.<i>Results.<i/> The methodology successfully segregates the clusters of galaxies into the three dynamical states. An examination of the projected galaxy distributions in optical wavelengths and gas distributions in X-ray further confirms the consistency of these classifications. The dynamical states of the clusters are statistically distinguishable, providing a clear categorization for further analysis.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"99 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-07DOI: 10.1051/0004-6361/202451898
Rémy Koskas, Jean-Michel Alimi
In a recent paper, we highlighted in wCDM models derived from general relativity (GR) (with Dark Energy Universe numerical simulation data), a cosmological invariance of the distribution of dark-matter (DM) halo shapes when expressed in terms of the nonlinear fluctuations of the cosmic matter field. This paper shows that this invariance persists when tested on numerical simulations performed with a different N-body solver, and that it is also robust to adding massive neutrinos to the cold DM component. Furthermore, this discovery raises crucial questions about the validity of this invariance in MG models. Thus, we examined whether it remains robust in the case of Hu & Sawicki model using DUSTGRAIN-pathfinder numerical simulations. By comparing the results of advanced numerical simulations in these different theoretical frameworks, we found significant deviations from the invariance observed in the framework of wCDM models of GR. These deviations suggest that the gravitation’s nature significantly influences the DM halos’ shape. We then interpreted this departure from the GR models’ invariance as a manifestation of the scalar-field screening effect corresponding to such f(R)-type theories. This one modifies the sphericization process of DM halos during their formation, precisely because the critical mass at which this scalar field becomes non-negligible is the mass at which the deviation appears. To this extent, the departure from cosmological invariance in DM halos’ shape is a cosmological probe of the nature of gravity, and the mass scale at which it appears can be used to estimate the fR0 parameter of such theories.
{"title":"Breaking the cosmological invariance of the dark-matter halo shape as a new probe of modified gravity","authors":"Rémy Koskas, Jean-Michel Alimi","doi":"10.1051/0004-6361/202451898","DOIUrl":"https://doi.org/10.1051/0004-6361/202451898","url":null,"abstract":"In a recent paper, we highlighted in <i>w<i/>CDM models derived from general relativity (GR) (with Dark Energy Universe numerical simulation data), a cosmological invariance of the distribution of dark-matter (DM) halo shapes when expressed in terms of the nonlinear fluctuations of the cosmic matter field. This paper shows that this invariance persists when tested on numerical simulations performed with a different <i>N<i/>-body solver, and that it is also robust to adding massive neutrinos to the cold DM component. Furthermore, this discovery raises crucial questions about the validity of this invariance in MG models. Thus, we examined whether it remains robust in the case of Hu & Sawicki model using DUSTGRAIN-<i>pathfinder<i/> numerical simulations. By comparing the results of advanced numerical simulations in these different theoretical frameworks, we found significant deviations from the invariance observed in the framework of <i>w<i/>CDM models of GR. These deviations suggest that the gravitation’s nature significantly influences the DM halos’ shape. We then interpreted this departure from the GR models’ invariance as a manifestation of the scalar-field screening effect corresponding to such <i>f<i/>(<i>R<i/>)-type theories. This one modifies the sphericization process of DM halos during their formation, precisely because the critical mass at which this scalar field becomes non-negligible is the mass at which the deviation appears. To this extent, the departure from cosmological invariance in DM halos’ shape is a cosmological probe of the nature of gravity, and the mass scale at which it appears can be used to estimate the <i>f<i/><sub><i>R<i/>0<sub/> parameter of such theories.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"24 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-07DOI: 10.1051/0004-6361/202452687
C. Grœneveld, R. J. van Weeren, A. Botteon, R. Cassano, F. de Gasperin, E. Osinga, G. Brunetti, H. J. A. Röttgering
Some galaxy clusters contain non-thermal synchrotron emitting plasma that permeate the intracluster medium (ICM). The spectral properties of this radio emission are not well characterised at decametre wavelengths (ν < 30 MHz), primarily due to the severe corrupting effects of the ionosphere. Using a recently developed calibration strategy, we present LOFAR images below 30 MHz of the low-mass galaxy cluster Abell 655, which was serendipitously detected in an observation of the bright calibrator 3C 196. We combine this observation with LOFAR data at 144 MHz and new band 4 upgraded Giant Metrewave Radio Telescope observations centred at 650 MHz. In the 15–30 MHz LOFAR image, diffuse emission is seen with a physical extent of about 700 kpc. We argue that the diffuse emission detected in this galaxy cluster likely has multiple origins. At higher frequencies (650 MHz), the diffuse emission resembles a radio halo, while at lower frequencies the emission seems to consist of several components and bar-like structures. This detection of diffuse emission suggests that most low-frequency emission in this cluster comes from re-energised fossil plasma from old Active Galacitic Nucleus outbursts co-existing with the radio halo component. By counting the number of cluster radio detections in the decametre band, we estimate that around a quarter of the Planck clusters host re-energised fossil plasma that is detectable in the decametre band with LOFAR.
{"title":"Serendipitous decametre detection of ultra steep spectrum radio emission in Abell 655","authors":"C. Grœneveld, R. J. van Weeren, A. Botteon, R. Cassano, F. de Gasperin, E. Osinga, G. Brunetti, H. J. A. Röttgering","doi":"10.1051/0004-6361/202452687","DOIUrl":"https://doi.org/10.1051/0004-6361/202452687","url":null,"abstract":"Some galaxy clusters contain non-thermal synchrotron emitting plasma that permeate the intracluster medium (ICM). The spectral properties of this radio emission are not well characterised at decametre wavelengths (<i>ν<i/> < 30 MHz), primarily due to the severe corrupting effects of the ionosphere. Using a recently developed calibration strategy, we present LOFAR images below 30 MHz of the low-mass galaxy cluster Abell 655, which was serendipitously detected in an observation of the bright calibrator 3C 196. We combine this observation with LOFAR data at 144 MHz and new band 4 upgraded Giant Metrewave Radio Telescope observations centred at 650 MHz. In the 15–30 MHz LOFAR image, diffuse emission is seen with a physical extent of about 700 kpc. We argue that the diffuse emission detected in this galaxy cluster likely has multiple origins. At higher frequencies (650 MHz), the diffuse emission resembles a radio halo, while at lower frequencies the emission seems to consist of several components and bar-like structures. This detection of diffuse emission suggests that most low-frequency emission in this cluster comes from re-energised fossil plasma from old Active Galacitic Nucleus outbursts co-existing with the radio halo component. By counting the number of cluster radio detections in the decametre band, we estimate that around a quarter of the Planck clusters host re-energised fossil plasma that is detectable in the decametre band with LOFAR.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"44 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-06DOI: 10.1051/0004-6361/202452408
S. Lin, W. Luo, Y. F. Cai, Q. Guo, L. Wei, B. Wang, Q. Li, C. Su, A. Rodriguez
We report the detection of a core with a size of 282 pc in the center of Milky Way dark matter halo at the 68% confidence level. It was detected using the microlensing event-rate sky map data from the optical gravitational lensing experiment (OGLE) survey. We applied the spatial information of the microlensing sky map and modeled it with the detailed Milky Way dark matter halo core-cusp profile, and with the fraction of dark matter in the form of mini dark matter structure (MDMS; fMDMS = ΩMDMS/ΩDM) such as a primordial black hole, Earth-mass subhalos, or floating planets. This sky map can simultaneously constrain fMDMS and the core size without a strong degeneracy while fully considering the mass function of Milky Way stellar components from the bulge and disk.
我们以 68% 的置信度报告了在银河系暗物质光环中心探测到一个大小为 282 pc 的核心。它是利用光学引力透镜实验（OGLE）巡天的微透镜事件率天图数据探测到的。我们应用了微透镜天图的空间信息，并将其与详细的银河系暗物质晕核心-尖顶剖面，以及以微型暗物质结构（MDMS；fMDMS = ΩMDMS/ΩDM）形式存在的暗物质部分（如原始黑洞、地球质量的亚halos或漂浮行星）进行了建模。这张星空图可以同时约束fMDMS和内核大小，而不会出现强烈的退化现象，同时还能充分考虑到来自隆起和星盘的银河恒星成分的质量函数。
{"title":"The density profile of Milky Way dark matter halo constrained from the OGLE microlensing sky map","authors":"S. Lin, W. Luo, Y. F. Cai, Q. Guo, L. Wei, B. Wang, Q. Li, C. Su, A. Rodriguez","doi":"10.1051/0004-6361/202452408","DOIUrl":"https://doi.org/10.1051/0004-6361/202452408","url":null,"abstract":"We report the detection of a core with a size of 282 pc in the center of Milky Way dark matter halo at the 68% confidence level. It was detected using the microlensing event-rate sky map data from the optical gravitational lensing experiment (OGLE) survey. We applied the spatial information of the microlensing sky map and modeled it with the detailed Milky Way dark matter halo core-cusp profile, and with the fraction of dark matter in the form of mini dark matter structure (MDMS; <i>f<i/><sub>MDMS<sub/> = Ω<sub>MDMS<sub/>/Ω<sub>DM<sub/>) such as a primordial black hole, Earth-mass subhalos, or floating planets. This sky map can simultaneously constrain <i>f<i/><sub>MDMS<sub/> and the core size without a strong degeneracy while fully considering the mass function of Milky Way stellar components from the bulge and disk.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"26 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-06DOI: 10.1051/0004-6361/202450170
Vartika Pandey, Philippe-A. Bourdin
Context. Numerical models of the solar atmosphere are widely used in solar research and provide insights into unsolved problems such as the heating of coronal loops. A prerequisite for such simulations is an initial condition for the plasma temperature and density. Many explicit numerical schemes employ high-order derivatives that require some diffusion, for example isotropic diffusion, for each independent variable to maintain numerical stability. Otherwise, significant numerical inaccuracies and subsequent wiggles will occur and grow at steep temperature gradients in the solar transition region.Aims. We tested how to adapt the isotropic heat conduction to the grid resolution so that the model is capable of resolving varying temperature gradients. Our ultimate goal is to construct an atmospheric stratification that can serve as an initial condition for multi-dimensional models.Methods. Our temperature stratification spans from the solar interior to the outer corona. From that, we computed the hydrostatic density stratification. Since numerical and analytical derivatives are not identical, the model needs to settle to a numerical equilibrium to fit all model parameters, such as mass diffusion and radiative losses. To compensate for energy losses in the corona, we implemented an artificial heating function that mimics the expected heat input from the 3D field-line braiding mechanism.Results. Our heating function maintains and stabilises the obtained coronal temperature stratification. However, the diffusivity parameters need to be adapted to the grid spacing. Unexpectedly, we find that higher grid resolutions may need larger diffusivities – contrary to the common understanding that high-resolution models are automatically more realistic and would need less diffusivity.Conclusions. Smaller grid spacing causes larger temperature gradients in the solar transition region and hence a greater potential for numerical problems. We conclude that isotropic heat conduction is an efficient remedy when using explicit schemes with high-order numerical derivatives.
{"title":"Investigating numerical stability by scaling heat conduction in a 1D hydrodynamic model of the solar atmosphere","authors":"Vartika Pandey, Philippe-A. Bourdin","doi":"10.1051/0004-6361/202450170","DOIUrl":"https://doi.org/10.1051/0004-6361/202450170","url":null,"abstract":"<i>Context.<i/> Numerical models of the solar atmosphere are widely used in solar research and provide insights into unsolved problems such as the heating of coronal loops. A prerequisite for such simulations is an initial condition for the plasma temperature and density. Many explicit numerical schemes employ high-order derivatives that require some diffusion, for example isotropic diffusion, for each independent variable to maintain numerical stability. Otherwise, significant numerical inaccuracies and subsequent wiggles will occur and grow at steep temperature gradients in the solar transition region.<i>Aims.<i/> We tested how to adapt the isotropic heat conduction to the grid resolution so that the model is capable of resolving varying temperature gradients. Our ultimate goal is to construct an atmospheric stratification that can serve as an initial condition for multi-dimensional models.<i>Methods.<i/> Our temperature stratification spans from the solar interior to the outer corona. From that, we computed the hydrostatic density stratification. Since numerical and analytical derivatives are not identical, the model needs to settle to a numerical equilibrium to fit all model parameters, such as mass diffusion and radiative losses. To compensate for energy losses in the corona, we implemented an artificial heating function that mimics the expected heat input from the 3D field-line braiding mechanism.<i>Results.<i/> Our heating function maintains and stabilises the obtained coronal temperature stratification. However, the diffusivity parameters need to be adapted to the grid spacing. Unexpectedly, we find that higher grid resolutions may need larger diffusivities – contrary to the common understanding that high-resolution models are automatically more realistic and would need less diffusivity.<i>Conclusions.<i/> Smaller grid spacing causes larger temperature gradients in the solar transition region and hence a greater potential for numerical problems. We conclude that isotropic heat conduction is an efficient remedy when using explicit schemes with high-order numerical derivatives.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"12 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-03DOI: 10.1051/0004-6361/202452794
Jakub Nadolny, Michał J. Michałowski, Massimiliano Parente, Martín Solar, Przemysław Nowaczyk, Oleh Ryzhov, Aleksandra Leśniewska
Context. Recent high-redshift (z > 4) spatially resolved observations with the James Webb Space Telescope have shown the evolution of the star formation rate (SFR) surface density (ΣSFR) and its main sequence in the ΣSFR − M* diagram (ΣSFRMS). The ΣSFRMS is already observed at cosmic morning (z ∼ 7.5). The use of ΣSFR is physically motivated because it is normalized by the area in which the star formation occurs, and this indirectly considers the gas density. The ΣSFR − M* diagram has been shown to complement the widely used (specific) SFR-M*, particularly when selecting passive galaxies.Aims. We establish the ΣSFR evolution since z = 12 in the framework of the L-GALAXIES2020 semi-analytical model (SAM), and we interpret recent observations.Methods. We estimated ΣSFR(–M*) and the cosmic star formation rate density (CSFRD) for the simulated galaxy population and for the subsamples, which were divided into stellar mass bins in the given redshift.Results. The simulated ΣSFR decreases by ∼3.5 dex from z = 12 to z = 0. We show that galaxies with different stellar masses have different paths of ΣSFR evolution. We find that ΣSFRMS is already observed at z ∼ 11. The simulated ΣSFRMS agrees with the observed one at z = 0, 1, 2, 5, and 7.5 and with individual galaxies at z > 10. We show that the highest ΣSFRMS slope of 0.709 ± 0.005 is at z ∼ 3 and decreases to ∼0.085 ± 0.003 at z = 0. This is mostly driven by a rapid decrease in SFR with an additional size increase for the most massive galaxies in this redshift range. This coincides with the dominance of the most massive galaxies in the CSFRD from the SAM. Observations show the same picture, in which the ΣSFR evolutionary path depends on the stellar mass, that is, more massive galaxies have higher ΣSFR at all redshifts. Finally, using the slope and normalization evolution, we derived the simulated ΣSFRMS as a function of stellar mass and redshift.
{"title":"Evolution of the star formation rate surface density main sequence","authors":"Jakub Nadolny, Michał J. Michałowski, Massimiliano Parente, Martín Solar, Przemysław Nowaczyk, Oleh Ryzhov, Aleksandra Leśniewska","doi":"10.1051/0004-6361/202452794","DOIUrl":"https://doi.org/10.1051/0004-6361/202452794","url":null,"abstract":"<i>Context.<i/> Recent high-redshift (<i>z<i/> > 4) spatially resolved observations with the James Webb Space Telescope have shown the evolution of the star formation rate (SFR) surface density (Σ<sub>SFR<sub/>) and its main sequence in the Σ<sub>SFR<sub/> − <i>M<i/><sub>*<sub/> diagram (Σ<sub>SFR<sub/>MS). The Σ<sub>SFR<sub/>MS is already observed at cosmic morning (<i>z<i/> ∼ 7.5). The use of Σ<sub>SFR<sub/> is physically motivated because it is normalized by the area in which the star formation occurs, and this indirectly considers the gas density. The Σ<sub>SFR<sub/> − <i>M<i/><sub>*<sub/> diagram has been shown to complement the widely used (specific) SFR-<i>M<i/><sub>*<sub/>, particularly when selecting passive galaxies.<i>Aims.<i/> We establish the Σ<sub>SFR<sub/> evolution since <i>z<i/> = 12 in the framework of the L-GALAXIES2020 semi-analytical model (SAM), and we interpret recent observations.<i>Methods.<i/> We estimated Σ<sub>SFR<sub/>(–<i>M<i/><sub>*<sub/>) and the cosmic star formation rate density (CSFRD) for the simulated galaxy population and for the subsamples, which were divided into stellar mass bins in the given redshift.<i>Results.<i/> The simulated Σ<sub>SFR<sub/> decreases by ∼3.5 dex from <i>z<i/> = 12 to <i>z<i/> = 0. We show that galaxies with different stellar masses have different paths of Σ<sub>SFR<sub/> evolution. We find that Σ<sub>SFR<sub/>MS is already observed at <i>z<i/> ∼ 11. The simulated Σ<sub>SFR<sub/>MS agrees with the observed one at <i>z<i/> = 0, 1, 2, 5, and 7.5 and with individual galaxies at <i>z<i/> > 10. We show that the highest Σ<sub>SFR<sub/>MS slope of 0.709 ± 0.005 is at <i>z<i/> ∼ 3 and decreases to ∼0.085 ± 0.003 at <i>z<i/> = 0. This is mostly driven by a rapid decrease in SFR with an additional size increase for the most massive galaxies in this redshift range. This coincides with the dominance of the most massive galaxies in the CSFRD from the SAM. Observations show the same picture, in which the Σ<sub>SFR<sub/> evolutionary path depends on the stellar mass, that is, more massive galaxies have higher Σ<sub>SFR<sub/> at all redshifts. Finally, using the slope and normalization evolution, we derived the simulated Σ<sub>SFR<sub/>MS as a function of stellar mass and redshift.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"41 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-03DOI: 10.1051/0004-6361/202451957
T. A. Movsessian, T. Yu. Magakian, A. V. Moiseev
Context. We continue to study the structure and kinematics of Herbig-Haro (HH) flows. HH flows exhibit a large variety of morphological and kinematical structures. Proper motion (PM) and radial velocity investigations are essential for understanding the physical nature of these structures.Aims. We investigated the kinematics and PM of spectrally separated structures in the PV Cep HH flow HH 215.Methods. We present observational results we obtained with a 6 m telescope (in Russia) using the SCORPIO multi-mode focal reducer with a scanning Fabry-Perot interferometer. Two epochs of the observations of the PV Cep region in Hα and [SII] emission (2003 and 2020–2021) allowed us to study the morphology of the HH 215 jet in detail and to measure the PM and radial velocities for its inner structures.Results. We studied previously known emission knots in the HH 215 flow and new features. Moreover, a newly formed HH knot was revealed. It presumably formed during the large maximum of PV Cep in 1976–1977. We found the high-velocity inner channel in the HH 215 ionized outflow, oriented in the mean direction of the whole HH outflow, and the symmetry axis of the reflection nebula. The position angle of the HH knots located along the axis of the high-velocity channel coincide with its axis (about 325°), but others have a completely different value (about 25°). This supports the idea that these knots were formed by oblique shocks. We derived a value of i ≈ 30° ± 5° for the inclination angle between the flow axis and the line of sight. The total length of the HH 215 outflow probably is about 0.2 pc, and the full length of the bipolar outflow from PV Cep (HH 315 + HH 215) can be estimated as 3.6 pc, assuming that the inclination angle is approximately stable.
{"title":"Two-epoch spectral imagery of the outflow system PV Cep","authors":"T. A. Movsessian, T. Yu. Magakian, A. V. Moiseev","doi":"10.1051/0004-6361/202451957","DOIUrl":"https://doi.org/10.1051/0004-6361/202451957","url":null,"abstract":"<i>Context.<i/> We continue to study the structure and kinematics of Herbig-Haro (HH) flows. HH flows exhibit a large variety of morphological and kinematical structures. Proper motion (PM) and radial velocity investigations are essential for understanding the physical nature of these structures.<i>Aims.<i/> We investigated the kinematics and PM of spectrally separated structures in the PV Cep HH flow HH 215.<i>Methods.<i/> We present observational results we obtained with a 6 m telescope (in Russia) using the SCORPIO multi-mode focal reducer with a scanning Fabry-Perot interferometer. Two epochs of the observations of the PV Cep region in H<i>α<i/> and [SII] emission (2003 and 2020–2021) allowed us to study the morphology of the HH 215 jet in detail and to measure the PM and radial velocities for its inner structures.<i>Results.<i/> We studied previously known emission knots in the HH 215 flow and new features. Moreover, a newly formed HH knot was revealed. It presumably formed during the large maximum of PV Cep in 1976–1977. We found the high-velocity inner channel in the HH 215 ionized outflow, oriented in the mean direction of the whole HH outflow, and the symmetry axis of the reflection nebula. The position angle of the HH knots located along the axis of the high-velocity channel coincide with its axis (about 325°), but others have a completely different value (about 25°). This supports the idea that these knots were formed by oblique shocks. We derived a value of i ≈ 30° ± 5° for the inclination angle between the flow axis and the line of sight. The total length of the HH 215 outflow probably is about 0.2 pc, and the full length of the bipolar outflow from PV Cep (HH 315 + HH 215) can be estimated as 3.6 pc, assuming that the inclination angle is approximately stable.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"41 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-03DOI: 10.1051/0004-6361/202452783
S. Howard, R. Helled, S. Müller
Context. Revealing the internal composition and structure of giant planets is fundamental for understanding planetary formation. However, the bulk composition can only be inferred through interior models. As a result, advancements in modelling aspects are essential to better characterise the interiors of giant planets.Aims. We investigate the effects of model assumptions such as the interior structure and the hydrogen–helium (H–He) equation of state (EOS) on the inferred interiors of giant exoplanets.Methods. We first assessed these effects on a few test cases and compared H–He EOSs. We then calculated evolution models and inferred the planetary bulk metallicity of 45 warm exoplanets, ranging from 0.1 to 10 MJ.Results. Planets with masses between about 0.2 and 0.6 MJ are most sensitive to the H–He EOS. Using a H–He EOS that properly models the warm dense matter regime reduces the inferred heavy-element mass, with an absolute difference in bulk metallicity of up to 13%. Concentrating heavy elements in a core, rather than distributing them uniformly (and scaling opacities with metallicity), reduces the inferred metallicity (up to 17%). The assumed internal structure, along with its effect on the envelope opacity, has the greatest effect on the inferred composition of massive planets (Mp > 4 MJ). For Mp > 0.6 MJ, the observational uncertainties on radii and ages lead to uncertainties in the inferred metallicity (up to 31%) that are larger than the ones associated with the used H–He EOS and the assumed interior structure. However, for planets with 0.2 < Mp < 0.6 MJ, the theoretical uncertainties are larger.Conclusions. Advancements in EOSs and our understanding of giant planet interior structures combined with accurate measurements of the planetary radius and age are crucial for characterising giant exoplanets.
{"title":"Giant exoplanet composition","authors":"S. Howard, R. Helled, S. Müller","doi":"10.1051/0004-6361/202452783","DOIUrl":"https://doi.org/10.1051/0004-6361/202452783","url":null,"abstract":"<i>Context.<i/> Revealing the internal composition and structure of giant planets is fundamental for understanding planetary formation. However, the bulk composition can only be inferred through interior models. As a result, advancements in modelling aspects are essential to better characterise the interiors of giant planets.<i>Aims.<i/> We investigate the effects of model assumptions such as the interior structure and the hydrogen–helium (H–He) equation of state (EOS) on the inferred interiors of giant exoplanets.<i>Methods.<i/> We first assessed these effects on a few test cases and compared H–He EOSs. We then calculated evolution models and inferred the planetary bulk metallicity of 45 warm exoplanets, ranging from 0.1 to 10 <i>M<i/><sub>J<sub/>.<i>Results.<i/> Planets with masses between about 0.2 and 0.6 <i>M<i/><sub>J<sub/> are most sensitive to the H–He EOS. Using a H–He EOS that properly models the warm dense matter regime reduces the inferred heavy-element mass, with an absolute difference in bulk metallicity of up to 13%. Concentrating heavy elements in a core, rather than distributing them uniformly (and scaling opacities with metallicity), reduces the inferred metallicity (up to 17%). The assumed internal structure, along with its effect on the envelope opacity, has the greatest effect on the inferred composition of massive planets (<i>M<i/><sub>p<sub/> > 4 <i>M<i/><sub>J<sub/>). For <i>M<i/><sub>p<sub/> > 0.6 <i>M<i/><sub>J<sub/>, the observational uncertainties on radii and ages lead to uncertainties in the inferred metallicity (up to 31%) that are larger than the ones associated with the used H–He EOS and the assumed interior structure. However, for planets with 0.2 < <i>M<i/><sub>p<sub/> < 0.6 <i>M<i/><sub>J<sub/>, the theoretical uncertainties are larger.<i>Conclusions.<i/> Advancements in EOSs and our understanding of giant planet interior structures combined with accurate measurements of the planetary radius and age are crucial for characterising giant exoplanets.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"96 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2025-01-03DOI: 10.1051/0004-6361/202452678
Pierfrancesco Di Cintio, Alessandro Alberto Trani
Context. Recent numerical results seem to suggest that, in certain regimes of typical particle velocities, when the post-Newtonian (PN) force terms are included, the gravitational N-body problem (for 3 ≤ N ≲ 103) is intrinsically less chaotic than its classical counterpart, which exhibits a slightly larger maximal Lyapunov exponent Λmax.Aims. In this work, we explore the dynamics of wildly chaotic, regular and nearly regular configurations of the three-body problem with and without the PN corrective terms, with the aim being to shed light on the behaviour of the Lyapunov spectra under the effect of the PN corrections.Methods. Because the interaction of the tangent-space dynamics in gravitating systems – which is needed to evaluate the Lyapunov exponents – becomes rapidly computationally heavy due to the complexity of the higher-order force derivatives involving multiple powers of v/c, we introduce a technique to compute a proxy of the Lyapunov spectrum based on the time-dependent diagonalization of the inertia tensor of a cluster of trajectories in phase-space. In addition, we also compare the dynamical entropy of the classical and relativistic cases.Results. We find that, for a broad range of orbital configurations, the relativistic three-body problem has a smaller Λmax than its classical counterpart starting with the exact same initial conditions. However, the other (positive) Lyapunov exponents can be either lower or larger than the corresponding classical ones, thus suggesting that the relativistic precession effectively reduces chaos only along one (or a few) directions in phase-space. As a general trend, the dynamical entropy of the relativistic simulations as a function of the rescaled speed of light falls below the classical value over a broad range of values.Conclusions. We observe that analyses based solely on Λmax could lead to misleading conclusions regarding the chaoticity of systems with small (and possibly large) N.
{"title":"Partial suppression of chaos in relativistic three-body problems","authors":"Pierfrancesco Di Cintio, Alessandro Alberto Trani","doi":"10.1051/0004-6361/202452678","DOIUrl":"https://doi.org/10.1051/0004-6361/202452678","url":null,"abstract":"<i>Context<i/>. Recent numerical results seem to suggest that, in certain regimes of typical particle velocities, when the post-Newtonian (PN) force terms are included, the gravitational <i>N<i/>-body problem (for 3 ≤ <i>N<i/> ≲ 10<sup>3<sup/>) is intrinsically less chaotic than its classical counterpart, which exhibits a slightly larger maximal Lyapunov exponent Λ<sub>max<sub/>.<i>Aims<i/>. In this work, we explore the dynamics of wildly chaotic, regular and nearly regular configurations of the three-body problem with and without the PN corrective terms, with the aim being to shed light on the behaviour of the Lyapunov spectra under the effect of the PN corrections.<i>Methods<i/>. Because the interaction of the tangent-space dynamics in gravitating systems – which is needed to evaluate the Lyapunov exponents – becomes rapidly computationally heavy due to the complexity of the higher-order force derivatives involving multiple powers of <i>v<i/>/<i>c<i/>, we introduce a technique to compute a proxy of the Lyapunov spectrum based on the time-dependent diagonalization of the inertia tensor of a cluster of trajectories in phase-space. In addition, we also compare the dynamical entropy of the classical and relativistic cases.<i>Results<i/>. We find that, for a broad range of orbital configurations, the relativistic three-body problem has a smaller Λ<sub>max<sub/> than its classical counterpart starting with the exact same initial conditions. However, the other (positive) Lyapunov exponents can be either lower or larger than the corresponding classical ones, thus suggesting that the relativistic precession effectively reduces chaos only along one (or a few) directions in phase-space. As a general trend, the dynamical entropy of the relativistic simulations as a function of the rescaled speed of light falls below the classical value over a broad range of values.<i>Conclusions<i/>. We observe that analyses based solely on Λ<sub>max<sub/> could lead to misleading conclusions regarding the chaoticity of systems with small (and possibly large) <i>N<i/>.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"36 1","pages":""},"PeriodicalIF":6.5,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
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