Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202449566
T. Lambert, R. Assef, C. Mazzucchelli, E. Bañados, M. Aravena, F. Barrientos, J. González-López, W. Hu, L. Infante, S. Malhotra, C. Moya-Sierralta, J. Rhoads, F. Valdes, J. Wang, I. Wold, Z. Zheng
High-redshift quasars are thought to live in the densest regions of space, which should be made evident by an overdensity of galaxies around them. However, campaigns to identify these overdensities by searching for Lyman-break galaxies (LBGs) and Lyman alpha emitters (LAEs) have had mixed results. These may be explained by either the small field of view of some of the experiments, the broad redshift ranges targeted by LBG searches, and the inherently high uncertainty of quasar redshifts estimated from ultraviolet emission lines, which makes it difficult to place the Ly-alpha emission line within a narrowband filter. Here, we present a 3 square degree search ($ 1000$ pMpc2) for LAEs around the $z=6.9$ quasar VIK J2348--3054 using the Dark Energy CAMera (DECam) housed on the 4m Blanco telescope, finding 38 LAEs. The systemic redshift of VIK J2348--3054 is known from ALMA CII observations and places the Ly-alpha emission line of companions within the NB964 narrowband of DECam. This is the largest field-of-view LAE search around a $z>6$ quasar conducted to date. We find that this field is sim ten times more overdense than Chandra Deep-Field South, observed previously with the same instrumental setup as well as several combined blank fields. This is strong evidence that VIK J2348--3054 resides in an overdensity of LAEs over several Mpc. Surprisingly, we find a lack of LAEs within 5 physical Mpc of the quasar and take this to most likely be evidence of quasar-suppressing star formation in its immediate vicinity. This result highlights the importance of performing overdensity searches over large areas to properly assess the density of those regions of the Universe.
{"title":"A lack of Lyman alpha emitters within 5Mpc of a luminous quasar in an overdensity at z=6.9: Potential evidence of negative quasar feedback at protocluster scales","authors":"T. Lambert, R. Assef, C. Mazzucchelli, E. Bañados, M. Aravena, F. Barrientos, J. González-López, W. Hu, L. Infante, S. Malhotra, C. Moya-Sierralta, J. Rhoads, F. Valdes, J. Wang, I. Wold, Z. Zheng","doi":"10.1051/0004-6361/202449566","DOIUrl":"https://doi.org/10.1051/0004-6361/202449566","url":null,"abstract":"High-redshift quasars are thought to live in the densest regions of space, which should be made evident by an overdensity of galaxies around them. However, campaigns to identify these overdensities by searching for Lyman-break galaxies (LBGs) and Lyman alpha emitters (LAEs) have had mixed results. These may be explained by either the small field of view of some of the experiments, the broad redshift ranges targeted by LBG searches, and the inherently high uncertainty of quasar redshifts estimated from ultraviolet emission lines, which makes it difficult to place the Ly-alpha emission line within a narrowband filter. Here, we present a 3 square degree search ($ 1000$ pMpc2) for LAEs around the $z=6.9$ quasar VIK J2348--3054 using the Dark Energy CAMera (DECam) housed on the 4m Blanco telescope, finding 38 LAEs. The systemic redshift of VIK J2348--3054 is known from ALMA CII observations and places the Ly-alpha emission line of companions within the NB964 narrowband of DECam. This is the largest field-of-view LAE search around a $z>6$ quasar conducted to date. We find that this field is sim ten times more overdense than Chandra Deep-Field South, observed previously with the same instrumental setup as well as several combined blank fields. This is strong evidence that VIK J2348--3054 resides in an overdensity of LAEs over several Mpc. Surprisingly, we find a lack of LAEs within 5 physical Mpc of the quasar and take this to most likely be evidence of quasar-suppressing star formation in its immediate vicinity. This result highlights the importance of performing overdensity searches over large areas to properly assess the density of those regions of the Universe.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"40 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141807631","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202450115
H. Wiesemeyer, R. Gusten, P. Hartogh, Yoko Okada, O. Ricken, J. Stutzki
The cosmic deuterium fraction, set by primordial nucleosynthesis and diminished by subsequent astration, is a valuable diagnostic tool to link the protosolar nebula to the history of star formation. However, in the present-day Solar System, the deuterium fraction in various carriers varies by more than an order of magnitude and reflects environmental conditions rather than the protosolar value. The latter is believed to be preserved in the atmospheres of the gas giant planets, yet determinations inferred from the CH$_3$D/CH$_4$ pair require a larger fractionation correction than those from HD/H$_2$, which are close to unity. The question of whether a stratospheric emission feature contaminates the absorption profile forming in subjacent layers was never addressed, owing to the lack of spectral resolving power. Here we report on the determination of the Jovian deuterium fraction using the rotational ground-state line of HD ($J=1-0$) at $ Employing the GREAT heterodyne spectrometer on board SOFIA, we detected the HD absorption and, thanks to the high resolving power, a weak stratospheric emission feature underneath; the former is blue-shifted with respect to the latter. The displacement is attributed to a pressure-induced line shift and reproduced by dedicated radiative-transfer modeling based on recent line-profile parameters. Using atmospheric standard models, we obtained $ D/H $, which agrees with a recent measurement in Saturn's atmosphere and with the value inferred from solar-wind measurements and meteoritic data. The result suggests that all three measurements represent bona fide protosolar D/H fractions. As a supplement and test for the consistency of the layering assumed in our model, we provide an analysis of the purely rotational $J=6-5$ line of CH$_4$ (in the vibrational ground state, at $ mu$m).
{"title":"Revisiting Jupiter's deuterium fraction in the rotational ground-state line of HD at high spectral resolution","authors":"H. Wiesemeyer, R. Gusten, P. Hartogh, Yoko Okada, O. Ricken, J. Stutzki","doi":"10.1051/0004-6361/202450115","DOIUrl":"https://doi.org/10.1051/0004-6361/202450115","url":null,"abstract":"The cosmic deuterium fraction, set by\u0000 primordial nucleosynthesis and diminished by subsequent astration, is a\u0000 valuable diagnostic tool to link the protosolar nebula to the history of\u0000 star formation. However, in the present-day Solar System, the deuterium\u0000 fraction in various carriers varies by more than an order of magnitude and reflects environmental\u0000 conditions rather than the protosolar value. The latter is believed to be\u0000 preserved in the atmospheres of the gas giant planets, yet determinations\u0000 inferred from the CH$_3$D/CH$_4$ pair require a larger fractionation\u0000 correction than those from HD/H$_2$, which are close to unity. The \u0000 question of whether a stratospheric emission feature contaminates the\u0000 absorption profile forming in subjacent layers was never addressed, owing to\u0000 the lack of spectral resolving power. Here we report on the\u0000 determination of the Jovian deuterium fraction using the\u0000 rotational ground-state line of HD ($J=1-0$) at $ Employing the GREAT heterodyne spectrometer on board SOFIA, we detected the HD absorption and, thanks to the high resolving power, a weak stratospheric emission feature underneath; the former is blue-shifted with respect to the latter. The displacement is attributed to a pressure-induced line shift and reproduced by dedicated radiative-transfer modeling based on recent line-profile parameters. Using atmospheric standard models, we obtained $ D/H $, which agrees with a recent\u0000 measurement in Saturn's atmosphere and with the\u0000 value inferred from solar-wind measurements and meteoritic data. The result\u0000 suggests that all three measurements represent bona fide protosolar\u0000 D/H fractions. As a supplement and test for the consistency of the layering\u0000 assumed in our model, we provide an analysis of the purely rotational\u0000 $J=6-5$ line of CH$_4$ (in the vibrational ground state, at \u0000 $ mu$m).","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"33 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141808572","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202450319
A. Sacchi, M. Imbrogno, S. Motta, P. Esposito, G. Israel, N. O. Pinciroli Vago, A. De Luca, M. Marelli, F. Pintore, G.A. Rodr'iguez Castillo, R. Salvaterra, A. Tiengo
We report on the multi-year evolution of the population of X-ray sources in the nuclear region of NGC 3621 based on and observations. Among these, two sources, X1 and X5, after their first detection in 2008, seem to have faded below the detectability threshold, a most interesting fact as X1 is associated with the active galactic nucleus (AGN) of the galaxy. Two other sources, X3 and X6, are presented for the first time, the former showing a peculiar short-term variability in the latest available dataset, suggesting an egress from eclipse, and hence belonging to the handful of known eclipsing ultra-luminous X-ray sources. One source, X4, previously known for its heartbeat (i.e. a characteristic modulation in its signal with a period of $ h), shows a steady behaviour in the latest observation. Finally, the brightest X-ray source in NGC 3621, here labelled X2, shows steady levels of flux across all the available datasets, but a change in its spectral shape, reminiscent of the behaviours of Galactic disc-fed X-ray binaries.
我们根据和观测数据报告了NGC 3621核区X射线源群的多年演变情况。其中，X1和X5这两个源在2008年首次被探测到之后，似乎就逐渐消失在可探测阈值以下了，这是一个非常有趣的事实，因为X1与该星系的活动星系核（AGN）有关。另外两个源，X3 和 X6，也是首次被提出来，前者在最新的数据集中显示出一种奇特的短期变化，这表明它们已经从日食中脱离，因此属于已知的少数日食超亮 X 射线源。有一个源，X4，以前因其心跳（即其信号中周期为 $ h 的特征调制）而闻名，在最新的观测中显示出稳定的行为。最后，NGC 3621 中最亮的 X 射线源，在这里被标记为 X2，在所有可用的数据集中都显示出稳定的通量水平，但其光谱形状却发生了变化，让人联想到银河系圆盘馈源 X 射线双星的行为。
{"title":"The restless population of bright X-ray sources of NGC 3621","authors":"A. Sacchi, M. Imbrogno, S. Motta, P. Esposito, G. Israel, N. O. Pinciroli Vago, A. De Luca, M. Marelli, F. Pintore, G.A. Rodr'iguez Castillo, R. Salvaterra, A. Tiengo","doi":"10.1051/0004-6361/202450319","DOIUrl":"https://doi.org/10.1051/0004-6361/202450319","url":null,"abstract":"We report on the multi-year evolution of the population of X-ray sources in the nuclear region of NGC 3621 based on and observations. Among these, two sources, X1 and X5, after their first detection in 2008, seem to have faded below the detectability threshold, a most interesting fact as X1 is associated with the active galactic nucleus (AGN) of the galaxy. Two other sources, X3 and X6, are presented for the first time, the former showing a peculiar short-term variability in the latest available dataset, suggesting an egress from eclipse, and hence belonging to the handful of known eclipsing ultra-luminous X-ray sources. One source, X4, previously known for its heartbeat (i.e. a characteristic modulation in its signal with a period of $ h), shows a steady behaviour in the latest observation. Finally, the brightest X-ray source in NGC 3621, here labelled X2, shows steady levels of flux across all the available datasets, but a change in its spectral shape, reminiscent of the behaviours of Galactic disc-fed X-ray binaries.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"67 32","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141806773","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202450342
J.P. Hu, J. Hu, X. Jia, B. Gao, F.Y. Wang
Cosmography can be used to constrain the kinematics of the Universe in a model-independent way. In this work, we attempt to combine the Pad$ e $ approximations with the latest Pantheon+ sample to test the cosmological principle. Based on the Pad$ e $ approximations, we first applied cosmographic constraints to different-order polynomials including third-order (Pad$ e $), fourth-order (Pad$ e $), and fifth-order (Pad$ e $) ones. The statistical analyses show that the Pad$ e $ polynomial has the best performance. Its best fits are $H_ $ = 72.53pm 0.28 km s$^ $ Mpc$^ $, $q_ $, and $j_ $. By further fixing $j_ $ = 1.00, it can be found that the Pad$ e $ polynomial can describe the Pantheon+ sample better than the regular Pad$ e $ polynomial and the usual cosmological models (including the Lambda CDM, $w$CDM, CPL, and $R_h$ = ct models). Based on the Pad$ e $ ($j_ $ = 1) polynomial and the hemisphere comparison method, we tested the cosmological principle and found the preferred directions of cosmic anisotropy, such as (l, b) = (304.6$^ circ circ $) and (311.1$^ circ circ $) for $q_ $ and $H_ $, respectively. These two directions are consistent with each other at a $1 confidence level, but the corresponding results of statistical isotropy analyses including isotropy and isotropy with real positions are quite different. The statistical significance of $ is stronger than that of $q_ $; that is, 4.75sigma and 4.39sigma for isotropy and isotropy with real positions, respectively. Reanalysis with fixed $q_ = -0.55$ (corresponds to $ m $ = 0.30) gives similar results. Overall, our model-independent results provide clear indications of a possible cosmic anisotropy, which must be taken seriously. Further testing is needed to better understand this signal.
宇宙学可以用来以一种与模型无关的方式约束宇宙运动学。在这项工作中，我们尝试将Pad$ e $近似与最新的Pantheon+样本相结合，来检验宇宙学原理。在Pad$ e $近似的基础上，我们首先将宇宙学约束应用于不同阶的多项式，包括三阶（Pad$ e $）、四阶（Pad$ e $）和五阶（Pad$ e $）多项式。统计分析显示，Pad$ e $ 多项式的性能最好。通过进一步固定$j_ $ = 1.00，可以发现Pad$ e $多项式对Pantheon+样本的描述优于常规的Pad$ e $多项式和通常的宇宙学模型（包括Lambda CDM、$w$CDM、CPL和$R_h$ = ct模型）。基于Pad$ e $ ($j_ $ = 1)多项式和半球比较法，我们检验了宇宙学原理，发现了宇宙各向异性的优选方向，如(l, b) = (304.6$^ circ circ $)和(311.1$^ circ circ $)分别为$q_ $和$H_ $。这两个方向在 1 美元的置信水平下是一致的，但包括各向同性和实位各向同性在内的统计各向同性分析的相应结果却大相径庭。$ 的统计显著性强于 $q_ $；即各向同性和实位各向同性的统计显著性分别为 4.75sigma 和 4.39sigma。用固定的 $q_ = -0.55$（相当于 $ m $ = 0.30）重新分析也得到了类似的结果。总之，我们与模型无关的结果清楚地表明了可能存在的宇宙各向异性，必须认真对待。要更好地理解这一信号，还需要进一步的测试。
{"title":"Testing cosmic anisotropy with Padé approximations and the latest Pantheon+ sample","authors":"J.P. Hu, J. Hu, X. Jia, B. Gao, F.Y. Wang","doi":"10.1051/0004-6361/202450342","DOIUrl":"https://doi.org/10.1051/0004-6361/202450342","url":null,"abstract":"Cosmography can be used to constrain the kinematics of the Universe in a model-independent way. In this work, we attempt to combine the Pad$ e $ approximations with the latest Pantheon+ sample to test the cosmological principle. Based on the Pad$ e $ approximations, we first applied cosmographic constraints to different-order polynomials including third-order (Pad$ e $), fourth-order (Pad$ e $), and fifth-order (Pad$ e $) ones. The statistical analyses show that the Pad$ e $ polynomial has the best performance. Its best fits are $H_ $ = 72.53pm 0.28 km s$^ $ Mpc$^ $, $q_ $, and $j_ $. By further fixing $j_ $ = 1.00, it can be found that the Pad$ e $ polynomial can describe the Pantheon+ sample better than the regular Pad$ e $ polynomial and the usual cosmological models (including the Lambda CDM, $w$CDM, CPL, and $R_h$ = ct models). Based on the Pad$ e $ ($j_ $ = 1) polynomial and the hemisphere comparison method, we tested the cosmological principle and found the preferred directions of cosmic anisotropy, such as (l, b) = (304.6$^ circ circ $) and (311.1$^ circ circ $) for $q_ $ and $H_ $, respectively. These two directions are consistent with each other at a $1 confidence level, but the corresponding results of statistical isotropy analyses including isotropy and isotropy with real positions are quite different. The statistical significance of $ is stronger than that of $q_ $; that is, 4.75sigma and 4.39sigma for isotropy and isotropy with real positions, respectively. Reanalysis with fixed $q_ = -0.55$ (corresponds to $ m $ = 0.30) gives similar results. Overall, our model-independent results provide clear indications of a possible cosmic anisotropy, which must be taken seriously. Further testing is needed to better understand this signal.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"11 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141808610","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202449734
P. Lazorenko, J. Sahlmann, M. Mayor, E.L. Martin
We investigate how to quantitatively model the observed differential image motion (DIM) in relative astrometric observations. As a test bed we used differential astrometric observations from the FORS2 camera of the Very Large Telescope (VLT) obtained during 2010--2019 under several programs of observations of southern brown dwarfs . The measured image motion was compared to models that decompose atmospheric turbulence in frequency space and translate the vertical turbulence profile into DIM amplitude. This approach accounts for the spatial filtering by the telescope's entrance pupil and the observation parameters (field size, zenith angle, reference star brightness and distribution, and exposure time), and it aggregates that information into a newly defined metric integral term. We demonstrate excellent agreement (within 1) between the model parameters derived from the DIM variance and determined by the observations. For a 30 s exposure of a typical 1 field close to the Galactic plane, image motion limits astrometric precision to sim 60 mu as when sixth-order transformation polynomial is applicable. We confirm that the measured image motion variance is well described by Kolmogorov-type turbulence with exponent 11/3 dependence on the field size at effective altitudes of 16--18 km, where the best part of the DIM is generated. Extrapolation to observations with extremely large telescopes enables the estimation of the astrometric precision limit for seeing-limited observations of sim 5 mu as, which has a variety of exciting scientific applications.
我们研究了如何对相对天体测量观测中观测到的差分图像运动（DIM）进行定量建模。作为测试平台，我们使用了超大望远镜（VLT）的 FORS2 相机在 2010-2019 年期间通过几个南方褐矮星观测项目获得的差分天体测量观测数据。测量到的图像运动与在频率空间分解大气湍流并将垂直湍流剖面转化为 DIM 振幅的模型进行了比较。这种方法考虑了望远镜入口瞳孔的空间过滤和观测参数（视场大小、天顶角、参考星亮度和分布以及曝光时间），并将这些信息汇总到一个新定义的度量积分项中。我们证明，由 DIM 方差得出的模型参数与观测参数之间的吻合度非常高（在 1 以内）。对于接近银河系平面的典型 1 个星场的 30 秒曝光，图像运动将天体测量精度限制在模拟 60 μm，因为六阶变换多项式是适用的。我们证实，在有效高度为 16-18 千米（DIM 的最佳部分产生于此高度）时，所测得的图像运动方差可以很好地用柯尔莫哥洛夫（Kolmogorov）型湍流来描述，湍流指数为 11/3，与星场大小有关。通过对超大望远镜的观测进行推断，可以估算出模拟 5 mu as 的视限观测的天体测量精度极限，这在科学上有着多种令人兴奋的应用。
{"title":"Differential image motion in astrometric observations with very large seeing-limited telescopes","authors":"P. Lazorenko, J. Sahlmann, M. Mayor, E.L. Martin","doi":"10.1051/0004-6361/202449734","DOIUrl":"https://doi.org/10.1051/0004-6361/202449734","url":null,"abstract":"We investigate how to quantitatively model the observed differential image motion (DIM) in relative astrometric observations. As a test bed we used differential astrometric observations from the FORS2 camera of the Very Large Telescope (VLT) obtained during 2010--2019 under several programs of observations of southern brown dwarfs . The measured image motion was compared to models that decompose atmospheric turbulence in frequency space and translate the vertical turbulence profile into DIM amplitude. This approach accounts for the spatial filtering by the telescope's entrance pupil and the observation parameters (field size, zenith angle, reference star brightness and distribution, and exposure time), and it aggregates that information into a newly defined metric integral term. We demonstrate excellent agreement (within 1) between the model parameters derived from the DIM variance and determined by the observations. For a 30 s exposure of a typical 1 field close to the Galactic plane, image motion limits astrometric precision to sim 60 mu as when sixth-order transformation polynomial is applicable. We confirm that the measured image motion variance is well described by Kolmogorov-type turbulence with exponent 11/3 dependence on the field size at effective altitudes of 16--18 km, where the best part of the DIM is generated. Extrapolation to observations with extremely large telescopes enables the estimation of the astrometric precision limit for seeing-limited observations of sim 5 mu as, which has a variety of exciting scientific applications.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"86 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141807834","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202449740
P. Palicio, F. Matteucci, M. Della Valle, E. Spitoni
Type Ia supernovae play a key role in the evolution of galaxies by polluting the interstellar medium with a fraction of iron peak elements larger than that released in the core-collapse supernova events. Their light curve, moreover, is widely used in cosmological studies as it constitutes a reliable distance indicator on extragalactic scales. Among the mechanisms proposed to explain the Type Ia supernovae (SNe), the single- and double-degenerate channels are thought to be the dominant ones, which implies a different distribution of time delays between the progenitor formation and the explosion. In this paper, we aim to determine the dominant mechanism by comparing a compilation of Type Ia SN rates with those computed from various cosmic star-formation histories coupled with different delay-time distribution functions. We also evaluate the relative contributions of both channels. By using a least-squares fitting procedure, we modeled the observations of Type Ia SN rates assuming different combinations of three recent cosmic star-formation rates and seven delay-time distributions. The goodness of these fits are statistically quantified by the $ test. For two of the three cosmic star-formation rates, the single degenerate scenario provides the most accurate explanation for the observations, while a combination of 34 single-degenerate- and 66 double-degenerate delay-time distributions is more plausible for the remaining tested cosmic star-formation rates. Though dependent on the assumed cosmic star-formation rate, we find arguments in favor of the single-degenerate model. From the theoretic point of view, at least sim 34 of the Type Ia SN must have been produced through the single-degenerate channel to account for the observations. The wide, double-degenerate mechanism slightly under-predicts the observations at redshift $z 1$, unless the cosmic SFR flattens in that regime. On the contrary, although the purely close double-degenerate scenario can be ruled out, we cannot rule out a mixed scenario with single- and double-degenerate progenitors.
Ia 型超新星在星系的演化过程中发挥着关键作用，因为它污染了星际介质，其铁峰值元素的比例大于核心坍缩超新星事件中释放的铁峰值元素的比例。此外，它们的光变曲线也被广泛用于宇宙学研究，因为它是银河系外尺度上可靠的距离指标。在解释 Ia 型超新星（SNe）的机制中，单衰变和双衰变通道被认为是最主要的，这意味着原生体形成和爆炸之间的时间延迟分布不同。在本文中，我们旨在通过比较 Ia 型 SN 的速率汇编和根据不同的宇宙恒星形成历史以及不同的延迟时间分布函数计算出的速率，来确定主导机制。我们还评估了两种渠道的相对贡献。通过使用最小二乘拟合程序，我们对Ia型SN速率的观测结果进行了建模，假设了三种近期宇宙恒星形成速率和七种延迟时间分布的不同组合。这些拟合的好坏通过 $ 检验进行统计量化。对于三种宇宙恒星形成率中的两种，单退化方案为观测提供了最准确的解释，而对于其余测试过的宇宙恒星形成率，34 种单退化和 66 种双退化延迟时间分布的组合则更为合理。尽管这取决于假定的宇宙恒星形成率，但我们发现了支持单衰变模型的论据。从理论的角度来看，至少有模拟 34 的 Ia 型 SN 必须是通过单衰变通道产生的，才能解释观测结果。宽幅双衰减机制对红移$z 1$处的观测结果的预测略显不足，除非宇宙SFR在该机制下趋于平缓。相反，虽然可以排除纯粹的近距离双蜕变情况，但我们不能排除有单蜕变和双蜕变原生体的混合情况。
{"title":"Cosmic Type Ia supernova rate and constraints on supernova Ia progenitors","authors":"P. Palicio, F. Matteucci, M. Della Valle, E. Spitoni","doi":"10.1051/0004-6361/202449740","DOIUrl":"https://doi.org/10.1051/0004-6361/202449740","url":null,"abstract":"Type Ia supernovae play a key role in the evolution of galaxies by polluting the interstellar medium with a fraction of iron peak elements larger than that released in the core-collapse supernova events. Their light curve, moreover, is widely used in cosmological studies as it constitutes a reliable distance indicator on extragalactic scales. Among the mechanisms proposed to explain the Type Ia supernovae (SNe), the single- and double-degenerate channels are thought to be the dominant ones, which implies a different distribution of time delays between the progenitor formation and the explosion. In this paper, we aim to determine the dominant mechanism by comparing a compilation of Type Ia SN rates with those computed from various cosmic star-formation histories coupled with different delay-time distribution functions. We also evaluate the relative contributions of both channels. By using a least-squares fitting procedure, we modeled the observations of Type Ia SN rates assuming different combinations of three recent cosmic star-formation rates and seven delay-time distributions. The goodness of these fits are statistically quantified by the $ test. For two of the three cosmic star-formation rates, the single degenerate scenario provides the most accurate explanation for the observations, while a combination of 34 single-degenerate- and 66 double-degenerate delay-time distributions is more plausible for the remaining tested cosmic star-formation rates. Though dependent on the assumed cosmic star-formation rate, we find arguments in favor of the single-degenerate model. From the theoretic point of view, at least sim 34 of the Type Ia SN must have been produced through the single-degenerate channel to account for the observations. The wide, double-degenerate mechanism slightly under-predicts the observations at redshift $z 1$, unless the cosmic SFR flattens in that regime. On the contrary, although the purely close double-degenerate scenario can be ruled out, we cannot rule out a mixed scenario with single- and double-degenerate progenitors.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"58 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141807093","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202450397
Hong-Chuan Ma, Min Du, Luis C. Ho, Ming-Jie Sheng, Shihong Liao
This work delves into the complex interaction between disk galaxies and their host dark matter halos. It specifically focuses on scenarios with minimal external ("nurture") influences such as mergers and substantial tidal interactions. The study uncovers the varied evolutionary paths of disk galaxies of different sizes, shaped by the initial conditions of their parent dark matter halos and subsequent internal processes. Thus, we can explore the ``nature'' of these galaxies. From the TNG50 simulation, a sample of 836 central disk galaxies with tiny stellar halos is chosen to study the inherent evolution of galaxies driven by nature. These galaxies are classified as compact, normal, or extended by referencing their locations on the mass-size ($M_ $) diagram. Scaling relations were then established to measure the correlations driven by internal mechanisms. This research demonstrates the distinctive evolutionary pathways of galaxies with different sizes in IllustrisTNG simulations, primarily driven by their nature. It is confirmed that disk galaxies inherit the angular momentum of their parent dark matter halos. More compact galaxies form earlier within halos that exhibit a lower specific angular momentum through heightened star formation during the early phase at redshifts above 2. During the later phase, the size of extended galaxies experiences more pronounced growth by accreting gas with a high angular momentum. Additionally, we reveal that many key characteristics of galaxies are linked to their mass and size: (1) compact galaxies tend to exhibit higher metal content, proportional to the potential well, $ M_ star R_ $; (2) compact galaxies host more massive bulges and black holes, along with a higher central concentration. Furthermore, our analysis indicates that galaxies of all types continue to actively engage in star formation, with no evident signs of quenching attributed to their varying sizes and angular momenta.
这项研究深入探讨了盘状星系与其宿主暗物质晕之间复杂的相互作用。它特别关注外部（"孕育"）影响最小的情况，如合并和大量潮汐相互作用。研究揭示了不同大小的盘状星系的不同演化路径，这些演化路径是由其母体暗物质晕的初始条件和随后的内部过程形成的。因此，我们可以探索这些星系的 "本质"。从TNG50模拟中，我们选取了836个具有微小恒星晕的中心盘星系样本，来研究星系受自然驱动的内在演化。根据这些星系在质量-大小（$M_ $）图中的位置，将它们分为紧凑星系、正常星系和扩展星系。然后建立比例关系来测量内部机制驱动的相关性。这项研究表明，在IllustrisTNG模拟中，不同大小的星系有着不同的演化路径，这主要是由它们的性质所驱动的。研究证实，盘状星系继承了其母体暗物质晕的角动量。在红移超过 2 的早期阶段，恒星形成速度加快，从而在比角动量较小的光环内较早形成了更紧凑的星系。在后期阶段，扩展星系的大小会因为吸积高角动量的气体而发生更明显的增长。此外，我们还揭示了星系的许多关键特征都与它们的质量和大小有关：（1）紧凑星系往往表现出较高的金属含量，与势阱成正比，即 $ M_ star R_$；（2）紧凑星系承载着更大质量的隆起和黑洞，以及更高的中心浓度。此外，我们的分析表明，各种类型的星系都在继续积极地进行恒星形成，并没有因为它们的大小和角矩不同而出现明显的熄灭迹象。
{"title":"Evolutionary pathways of disk galaxies with different sizes","authors":"Hong-Chuan Ma, Min Du, Luis C. Ho, Ming-Jie Sheng, Shihong Liao","doi":"10.1051/0004-6361/202450397","DOIUrl":"https://doi.org/10.1051/0004-6361/202450397","url":null,"abstract":"This work delves into the complex interaction between disk galaxies and their host dark matter halos. It specifically focuses on scenarios with minimal external (\"nurture\") influences such as mergers and substantial tidal interactions. The study uncovers the varied evolutionary paths of disk galaxies of different sizes, shaped by the initial conditions of their parent dark matter halos and subsequent internal processes. Thus, we can explore the ``nature'' of these galaxies. From the TNG50 simulation, a sample of 836 central disk galaxies with tiny stellar halos is chosen to study the inherent evolution of galaxies driven by nature. These galaxies are classified as compact, normal, or extended by referencing their locations on the mass-size ($M_ $) diagram. Scaling relations were then established to measure the correlations driven by internal mechanisms. This research demonstrates the distinctive evolutionary pathways of galaxies with different sizes in IllustrisTNG simulations, primarily driven by their nature. It is confirmed that disk galaxies inherit the angular momentum of their parent dark matter halos. More compact galaxies form earlier within halos that exhibit a lower specific angular momentum through heightened star formation during the early phase at redshifts above 2. During the later phase, the size of extended galaxies experiences more pronounced growth by accreting gas with a high angular momentum. Additionally, we reveal that many key characteristics of galaxies are linked to their mass and size: (1) compact galaxies tend to exhibit higher metal content, proportional to the potential well, $ M_ star R_ $; (2) compact galaxies host more massive bulges and black holes, along with a higher central concentration. Furthermore, our analysis indicates that galaxies of all types continue to actively engage in star formation, with no evident signs of quenching attributed to their varying sizes and angular momenta.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"32 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141807312","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202348964
H. Netzel, V. Varga, R. Szabo, R. Smolec, E. Plachy
Over recent years, additional low-amplitude non-radial modes have been detected in many first-overtone RR Lyrae stars. These non-radial modes form a characteristic period ratio with the dominant first overtone of around 0.61. The incidence rate of this phenomenon varies from population to population. It is also strongly dependent on the quality of the analyzed data. Current models aimed at explaining these additional signals involve non-radial modes of degrees of 8 and 9. Using synthetic horizontal branch populations, we investigate the incidence rate of first-overtone RR Lyrae stars with non-radial modes, depending on the population properties, namely, ages and metallicities. We compare our results with the observed results for globular clusters and the vast collection of field first-overtone RR Lyrae stars to test the model predictions. We used synthetic horizontal branches combined with pulsation models to predict how the incidence rate would depend on the age and metallicity of the population. To test whether the results based on synthetic horizontal branches are realistic, we compared them to incidence rates observed by TESS in first-overtone field RR Lyrae stars, using photometric metallicity values from a newly established calibration for TESS. The analysis of synthetic horizontal branches indicates that the incidence rate decreases with decreasing metallicity. We inferred the photometric metallicity for RR Lyrae stars observed by TESS and showed that the theoretical predictions are in agreement with the observations. Using the same method, we also concluded that the metallicity distribution of RR Lyrae stars showing an additional mode with a period-ratio around $0.68$ appears to be different from that of 1) all first-overtone stars and 2) those showing additional non-radial modes.
{"title":"Considering the incidence rate of RR Lyrae stars with non-radial modes","authors":"H. Netzel, V. Varga, R. Szabo, R. Smolec, E. Plachy","doi":"10.1051/0004-6361/202348964","DOIUrl":"https://doi.org/10.1051/0004-6361/202348964","url":null,"abstract":"Over recent years, additional low-amplitude non-radial modes have been detected in many first-overtone RR Lyrae stars. These non-radial modes form a characteristic period ratio with the dominant first overtone of around 0.61. The incidence rate of this phenomenon varies from population to population. It is also strongly dependent on the quality of the analyzed data. Current models aimed at explaining these additional signals involve non-radial modes of degrees of 8 and 9. Using synthetic horizontal branch populations, we investigate the incidence rate of first-overtone RR Lyrae stars with non-radial modes, depending on the population properties, namely, ages and metallicities. We compare our results with the observed results for globular clusters and the vast collection of field first-overtone RR Lyrae stars to test the model predictions. We used synthetic horizontal branches combined with pulsation models to predict how the incidence rate would depend on the age and metallicity of the population. To test whether the results based on synthetic horizontal branches are realistic, we compared them to incidence rates observed by TESS in first-overtone field RR Lyrae stars, using photometric metallicity values from a newly established calibration for TESS. The analysis of synthetic horizontal branches indicates that the incidence rate decreases with decreasing metallicity. We inferred the photometric metallicity for RR Lyrae stars observed by TESS and showed that the theoretical predictions are in agreement with the observations. Using the same method, we also concluded that the metallicity distribution of RR Lyrae stars showing an additional mode with a period-ratio around $0.68$ appears to be different from that of 1) all first-overtone stars and 2) those showing additional non-radial modes.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"92 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141807810","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202449780
Matteo D'Anna, G. Janett, L. Belluzzi
Making the conversion from the geometrical spatial scale to the optical depth spatial scale is useful in obtaining numerical solutions for the radiative transfer equation. This is because it allows for the use of exponential integrators, while enforcing numerical stability. Such a conversion involves the integration of the total opacity of the medium along the considered ray path. This is usually approximated by applying a piecewise quadrature in each spatial cell of the discretized medium. However, a rigorous analysis of this numerical step is lacking. This work is aimed at clearly assessing the performance of different optical depth conversion schemes with respect to the solution of the radiative transfer problem for polarized radiation, out of the local thermodynamic equilibrium. We analyzed different optical depth conversion schemes and their combinations with common formal solvers, both in terms of the rate of convergence as a function of the number of spatial points and the accuracy of the emergent Stokes profiles. The analysis was performed in a 1D semi-empirical model of the solar atmosphere, both in the absence and in the presence of a magnetic field. We solved the transfer problem of polarized radiation in different settings: the continuum, the photospheric Sr i AA modeled under the assumption of complete frequency redistribution, and the chromospheric Ca i AA taking the partial frequency redistribution effects into account during the modeling. High-order conversion schemes generally outperform low-order methods when a sufficiently high number of spatial grid points is considered. In the synthesis of the emergent Stokes profiles, the convergence rate, as a function of the number of spatial points, is impacted by both the conversion scheme and formal solver. The use of low-order conversion schemes significantly reduces the accuracy of high-order formal solvers. In practical applications, the use of low-order optical depth conversion schemes introduces large numerical errors in the formal solution. To fully exploit high-order formal solvers and obtain accurate synthetic emergent Stokes profiles, it is necessary to use high-order optical depth conversion schemes.
将几何空间尺度转换为光学深度空间尺度有助于获得辐射传递方程的数值解。这种转换涉及沿所考虑的射线路径对介质的总不透明度进行积分，通常通过在离散介质的每个空间单元中应用分段正交来近似实现。然而，目前还缺乏对这一数值步骤的严格分析。这项工作旨在明确评估不同光学深度转换方案在解决偏振辐射辐射传递问题方面的性能，以及在局部热力学平衡状态下的性能。我们分析了不同的光学深度转换方案及其与普通形式求解器的组合，包括作为空间点数量函数的收敛速度和出现的斯托克斯剖面的精确度。我们在不同的环境中解决了偏振辐射的转移问题：连续体、在完全频率再分布假设下建模的光球层 Sr i AA，以及在建模过程中考虑了部分频率再分布效应的色球层 Ca i AA。在合成新出现的斯托克斯剖面时，收敛速度作为空间点数的函数，受到转换方案和形式求解器的影响。在实际应用中，使用低阶光学深度转换方案会在形式解中产生较大的数值误差。要充分利用高阶形式解算器并获得精确的合成新兴斯托克斯剖面，就必须使用高阶光学深度转换方案。
{"title":"Impact of the numerical conversion to optical depth \u0000on the transfer of polarized radiation","authors":"Matteo D'Anna, G. Janett, L. Belluzzi","doi":"10.1051/0004-6361/202449780","DOIUrl":"https://doi.org/10.1051/0004-6361/202449780","url":null,"abstract":"Making the conversion from the geometrical spatial scale to the optical depth spatial scale is useful\u0000in obtaining numerical solutions for the radiative transfer equation. This is because it allows for the use of exponential integrators,\u0000while enforcing numerical stability.\u0000Such a conversion involves the integration of the total opacity of the medium along the considered ray path.\u0000This is usually approximated by applying a piecewise quadrature in each spatial cell of the discretized medium. However, a rigorous analysis of this numerical step\u0000\u0000is lacking. This work is aimed at clearly assessing the performance of different optical depth conversion schemes\u0000with respect to the solution of the radiative transfer \u0000problem for polarized radiation, out of the local thermodynamic equilibrium. We analyzed different optical depth conversion schemes and their combinations with common formal solvers, both\u0000in terms of the rate of convergence as a function of the number of spatial points and \u0000the accuracy of the emergent Stokes profiles.\u0000\u0000The analysis was performed in a 1D semi-empirical model of the solar atmosphere,\u0000both in the absence and in the presence of a magnetic field. We solved the transfer problem of polarized radiation in different settings:\u0000the continuum, the photospheric \u0000Sr i AA modeled under the assumption of complete frequency redistribution, \u0000and the chromospheric Ca i AA taking the partial frequency redistribution effects into account during the modeling. High-order conversion schemes generally outperform low-order methods when a sufficiently high number of spatial grid points is considered.\u0000In the synthesis of the emergent Stokes profiles, the convergence rate, as a function of the number of spatial points, is impacted by both \u0000the conversion scheme and formal solver.\u0000The use of low-order conversion schemes significantly reduces the accuracy of high-order formal solvers. In practical applications, the use of low-order optical depth conversion schemes\u0000introduces large numerical errors in the formal solution.\u0000\u0000To fully exploit high-order formal solvers and obtain accurate synthetic emergent Stokes profiles,\u0000it is necessary to use high-order optical depth conversion schemes.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"24 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141808643","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}
Pub Date : 2024-07-24DOI: 10.1051/0004-6361/202449768
A. Calabrò, L. Pentericci, P. Santini, A. Ferrara, M. Llerena, S. Mascia, L. Napolitano, L. Yung, L. Bisigello, M. Castellano, N. Cleri, A. Dekel, M. Dickinson, M. Franco, M. Giavalisco, M. Hirschmann, B. Holwerda, A. Koekemoer, R. A. Lucas, F. Pacucci, N. Pirzkal, G. Roberts-Borsani, L. Seillé, S. Tacchella, S. Wilkins, R. Amor'in, P. Arrabal Haro, M. Bagley, S. Finkelstein, J. Kartaltepe, C. Papovich
The galaxy-integrated star formation rate (SFR) surface density measurement ($ SFR $) has been proposed as a valuable diagnostic of the mass accumulation in galaxies given it is more tightly related to the physics of star formation and stellar feedback than other indicators. In this work, we assembled a statistical sample of $230$ galaxies observed with JWST in the GLASS and CEERS spectroscopic surveys to estimate Balmer line-based dust attenuations and SFRs (i.e., from Halpha , Hbeta , and Hgamma ), along with the UV rest-frame effective radii. We studied the evolution of galaxy SFR and $ SFR $ in the first $1.5$ billion years of our Universe, from a redshift of $z to $z We found that $ SFR $ is mildly increasing with redshift with a linear slope of $0.16 0.06$. We explored the dependence of SFR and $ SFR $ on stellar mass, showing that a star-forming main sequence and a $ SFR $ main sequence are present out to $z=10$. This dependence exhibits a similar slope compared to the same relations at lower redshifts, but with a higher normalization. We find that the specific SFR (sSFR) and $ SFR $ are correlated with the ratio and with indirect estimates of the escape fraction of Lyman continuum photons; hence, they are likely to play an important role in the evolution of ionization conditions at higher redshifts and in the escape of ionizing radiation. We also searched for spectral outflow signatures in the Halpha and emission lines in a subset of galaxies observed at high resolution (R$=2700$) by the GLASS survey, finding an outflow incidence of $2/11$ 32 9 $) at $z<6$, but no evidence at $z>6$ ($0/6$, $<26$). Finally, we find a positive correlation between A$_V$ and $ SFR $, and a flat trend as a function of sSFR, indicating that there is no evidence of a drop in A$_V$ in extremely star-forming galaxies between $z 4$ and $ 10$. This result might be at odds with a dust-clearing outflow scenario, which may instead take place at redshifts of $z 10$, as suggested by some theoretical models.
{"title":"Evolution of the star formation rate and Sigma_SFR of galaxies at cosmic morning (4","authors":"A. Calabrò, L. Pentericci, P. Santini, A. Ferrara, M. Llerena, S. Mascia, L. Napolitano, L. Yung, L. Bisigello, M. Castellano, N. Cleri, A. Dekel, M. Dickinson, M. Franco, M. Giavalisco, M. Hirschmann, B. Holwerda, A. Koekemoer, R. A. Lucas, F. Pacucci, N. Pirzkal, G. Roberts-Borsani, L. Seillé, S. Tacchella, S. Wilkins, R. Amor'in, P. Arrabal Haro, M. Bagley, S. Finkelstein, J. Kartaltepe, C. Papovich","doi":"10.1051/0004-6361/202449768","DOIUrl":"https://doi.org/10.1051/0004-6361/202449768","url":null,"abstract":"The galaxy-integrated star formation rate (SFR) surface density measurement ($ SFR $) has been proposed as a valuable diagnostic of the mass accumulation in galaxies given it is more tightly related to the physics of star formation and stellar feedback than other indicators. In this work, we assembled a statistical sample of $230$ galaxies observed with JWST in the GLASS and CEERS spectroscopic surveys to estimate Balmer line-based dust attenuations and SFRs (i.e., from Halpha , Hbeta , and Hgamma ), along with the UV rest-frame effective radii. We studied the evolution of galaxy SFR and $ SFR $ in the first $1.5$ billion years of our Universe, from a redshift of $z to $z We found that $ SFR $ is mildly increasing with redshift with a linear slope of $0.16 0.06$. We explored the dependence of SFR and $ SFR $ on stellar mass, showing that a star-forming main sequence and a $ SFR $ main sequence are present out to $z=10$. This dependence exhibits a similar slope compared to the same relations at lower redshifts, but with a higher normalization. We find that the specific SFR (sSFR) and $ SFR $ are correlated with the ratio and with indirect estimates of the escape fraction of Lyman continuum photons; hence, they are likely to play an important role in the evolution of ionization conditions at higher redshifts and in the escape of ionizing radiation. We also searched for spectral outflow signatures in the Halpha and emission lines in a subset of galaxies observed at high resolution (R$=2700$) by the GLASS survey, finding an outflow incidence of $2/11$ 32 9 $) at $z<6$, but no evidence at $z>6$ ($0/6$, $<26$). Finally, we find a positive correlation between A$_V$ and $ SFR $, and a flat trend as a function of sSFR, indicating that there is no evidence of a drop in A$_V$ in extremely star-forming galaxies between $z 4$ and $ 10$. This result might be at odds with a dust-clearing outflow scenario, which may instead take place at redshifts of $z 10$, as suggested by some theoretical models.","PeriodicalId":8585,"journal":{"name":"Astronomy & Astrophysics","volume":"35 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141807298","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}
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