{"title":"C","authors":"M. Gounelle, M. Chaussidon, Claire Rollion-Bard","doi":"10.1515/9783110580389-004","DOIUrl":null,"url":null,"abstract":"The base of the convection zone (CZ) is a source of acoustic glitches in the asteroseismic frequency spectra of solar-like oscillators, allowing one to precisely measure the acoustic depth to the feature. We examine the sensitivity of the depth of the CZ to mass, stellar abundances, and input physics, and in particular, the use of a measurement of the acoustic depth to the CZ as an atmosphere-independent, absolute measure of stellar metallicities. We find that for low-mass stars on the main sequence with 0.4 M M 1.6 M , the acoustic depth to the base of the CZ, normalized by the acoustic depth to the center of the star, τcz,n, is both a strong function of mass, and varies at the 0.5%–1% per 0.1 dex level in [Z/X], and is therefore also a sensitive probe of the composition. We estimate the theoretical uncertainties in the stellar models and show that combined with reasonable observational uncertainties we can expect to measure the metallicity to within 0.15–0.3 dex for solar-like stars. We discuss the applications of this work to rotational mixing, particularly in the context of the observed mid-F star Li dip, and to distinguishing between different mixtures of heavy elements.","PeriodicalId":288401,"journal":{"name":"International Directory of Arts 2019","volume":"42 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2018-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"C\",\"authors\":\"M. Gounelle, M. Chaussidon, Claire Rollion-Bard\",\"doi\":\"10.1515/9783110580389-004\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The base of the convection zone (CZ) is a source of acoustic glitches in the asteroseismic frequency spectra of solar-like oscillators, allowing one to precisely measure the acoustic depth to the feature. We examine the sensitivity of the depth of the CZ to mass, stellar abundances, and input physics, and in particular, the use of a measurement of the acoustic depth to the CZ as an atmosphere-independent, absolute measure of stellar metallicities. We find that for low-mass stars on the main sequence with 0.4 M M 1.6 M , the acoustic depth to the base of the CZ, normalized by the acoustic depth to the center of the star, τcz,n, is both a strong function of mass, and varies at the 0.5%–1% per 0.1 dex level in [Z/X], and is therefore also a sensitive probe of the composition. We estimate the theoretical uncertainties in the stellar models and show that combined with reasonable observational uncertainties we can expect to measure the metallicity to within 0.15–0.3 dex for solar-like stars. We discuss the applications of this work to rotational mixing, particularly in the context of the observed mid-F star Li dip, and to distinguishing between different mixtures of heavy elements.\",\"PeriodicalId\":288401,\"journal\":{\"name\":\"International Directory of Arts 2019\",\"volume\":\"42 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2018-10-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Directory of Arts 2019\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1515/9783110580389-004\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Directory of Arts 2019","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1515/9783110580389-004","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
摘要
对流区(CZ)的底部是类太阳振子的星震频谱中的声学小故障的来源,使人们能够精确地测量该特征的声学深度。我们研究了CZ深度对质量,恒星丰度和输入物理的敏感性,特别是使用CZ的声学深度测量作为与大气无关的恒星金属丰度的绝对测量。我们发现,对于0.4 M ~ 1.6 M主序上的低质量恒星,CZ底部的声深,经恒星中心的声深归一化后,τcz,n不仅是质量的强函数,而且在[Z/X]中每0.1个指数水平变化0.5% ~ 1%,因此也是组成的敏感探针。我们估计了恒星模型中的理论不确定性,并表明结合合理的观测不确定性,我们可以期望测量到类太阳恒星的金属丰度在0.15-0.3指数范围内。我们讨论了这项工作在旋转混合中的应用,特别是在观测到的中f星Li倾角的背景下,以及区分不同的重元素混合物。
The base of the convection zone (CZ) is a source of acoustic glitches in the asteroseismic frequency spectra of solar-like oscillators, allowing one to precisely measure the acoustic depth to the feature. We examine the sensitivity of the depth of the CZ to mass, stellar abundances, and input physics, and in particular, the use of a measurement of the acoustic depth to the CZ as an atmosphere-independent, absolute measure of stellar metallicities. We find that for low-mass stars on the main sequence with 0.4 M M 1.6 M , the acoustic depth to the base of the CZ, normalized by the acoustic depth to the center of the star, τcz,n, is both a strong function of mass, and varies at the 0.5%–1% per 0.1 dex level in [Z/X], and is therefore also a sensitive probe of the composition. We estimate the theoretical uncertainties in the stellar models and show that combined with reasonable observational uncertainties we can expect to measure the metallicity to within 0.15–0.3 dex for solar-like stars. We discuss the applications of this work to rotational mixing, particularly in the context of the observed mid-F star Li dip, and to distinguishing between different mixtures of heavy elements.