MAGIS (Measuring Abundances of red super Giants with Infrared Spectroscopy) project

IF 5.4 2区 物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS Astronomy & Astrophysics Pub Date : 2025-01-15 DOI:10.1051/0004-6361/202452392
Daisuke Taniguchi, Noriyuki Matsunaga, Naoto Kobayashi, Mingjie Jian, Brian Thorsbro, Kei Fukue, Satoshi Hamano, Yuji Ikeda, Hideyo Kawakita, Sohei Kondo, Shogo Otsubo, Hiroaki Sameshima, Takuji Tsujimoto, Chikako Yasui
{"title":"MAGIS (Measuring Abundances of red super Giants with Infrared Spectroscopy) project","authors":"Daisuke Taniguchi, Noriyuki Matsunaga, Naoto Kobayashi, Mingjie Jian, Brian Thorsbro, Kei Fukue, Satoshi Hamano, Yuji Ikeda, Hideyo Kawakita, Sohei Kondo, Shogo Otsubo, Hiroaki Sameshima, Takuji Tsujimoto, Chikako Yasui","doi":"10.1051/0004-6361/202452392","DOIUrl":null,"url":null,"abstract":"<i>Context<i/>. Given their high luminosities (<i>L<i/> ≳ 10<sup>4<sup/> <i>L<i/><sub>⊙<sub/>), red supergiants (RSGs) are good tracers of the chemical abundances of the young stellar population in the Milky Way and nearby galaxies. However, previous abundance analyses tailored to RSGs suffer some systematic uncertainties originating in, most notably, the synthesized molecular spectral lines for RSGs.<i>Aims<i/>. We establish a new abundance analysis procedure for RSGs that circumvents difficulties faced in previous works, and test the procedure with ten nearby RSGs observed with the near-infrared high-resolution spectrograph WINERED (0.97−1.32 µm, <i>R<i/> = 28 000). The wavelength range covered here is advantageous in that the molecular lines contaminating atomic lines of interest are mostly weak.<i>Methods<i/>. We first determined the effective temperatures (<i>T<i/><sub>eff<sub/>) of the targets with the line-depth ratio (LDR) method, and calculated the surface gravities (log 𝑔) according to the Stefan-Boltzmann law. We then determined the microturbulent velocities (<i>v<i/><sub>micro<sub/>) and metallicities ([Fe/H]) simultaneously through the fitting of individual Fe I lines. Finally, we also determined the abundance ratios ([X/Fe] for element X) through the fitting of individual lines.<i>Results<i/>. We determined the [X/Fe] of ten elements (Na I, Mg I, Al I, Si I, K I, Ca I, Ti I, Cr I, Ni I, and Y II). We estimated the relative precision in the derived abundances to be 0.04−0.12 dex for elements with more than two lines analyzed (e.g., Fe I and Mg I) and up to 0.18dex for the other elements (e.g., Y II). We compared the resultant abundances of RSGs with the well-established abundances of another type of young star, namely the Cepheids, in order to evaluate the potential systematic bias in our abundance measurements, assuming that the young stars (i.e., both RSGs and Cepheids) in the solar neighborhood have common chemical abundances. We find that the determined RSG abundances are highly consistent with those of Cepheids within <0.1 dex for some elements (notably [Fe/H] and [Mg/Fe]), which means the bias in the abundance determination for these elements is likely to be small. In contrast, the consistency is worse for some other elements (e.g., [Si/Fe] and [Y/Fe]). Nevertheless, the dispersion of the chemical abundances among our target RSGs is comparable with the individual statistical errors on the abundances. Hence, the procedure is likely to be useful to evaluate the relative difference in chemical abundances among RSGs.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"51 1","pages":""},"PeriodicalIF":5.4000,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Astronomy & Astrophysics","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1051/0004-6361/202452392","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0

Abstract

Context. Given their high luminosities (L ≳ 104 L), red supergiants (RSGs) are good tracers of the chemical abundances of the young stellar population in the Milky Way and nearby galaxies. However, previous abundance analyses tailored to RSGs suffer some systematic uncertainties originating in, most notably, the synthesized molecular spectral lines for RSGs.Aims. We establish a new abundance analysis procedure for RSGs that circumvents difficulties faced in previous works, and test the procedure with ten nearby RSGs observed with the near-infrared high-resolution spectrograph WINERED (0.97−1.32 µm, R = 28 000). The wavelength range covered here is advantageous in that the molecular lines contaminating atomic lines of interest are mostly weak.Methods. We first determined the effective temperatures (Teff) of the targets with the line-depth ratio (LDR) method, and calculated the surface gravities (log 𝑔) according to the Stefan-Boltzmann law. We then determined the microturbulent velocities (vmicro) and metallicities ([Fe/H]) simultaneously through the fitting of individual Fe I lines. Finally, we also determined the abundance ratios ([X/Fe] for element X) through the fitting of individual lines.Results. We determined the [X/Fe] of ten elements (Na I, Mg I, Al I, Si I, K I, Ca I, Ti I, Cr I, Ni I, and Y II). We estimated the relative precision in the derived abundances to be 0.04−0.12 dex for elements with more than two lines analyzed (e.g., Fe I and Mg I) and up to 0.18dex for the other elements (e.g., Y II). We compared the resultant abundances of RSGs with the well-established abundances of another type of young star, namely the Cepheids, in order to evaluate the potential systematic bias in our abundance measurements, assuming that the young stars (i.e., both RSGs and Cepheids) in the solar neighborhood have common chemical abundances. We find that the determined RSG abundances are highly consistent with those of Cepheids within <0.1 dex for some elements (notably [Fe/H] and [Mg/Fe]), which means the bias in the abundance determination for these elements is likely to be small. In contrast, the consistency is worse for some other elements (e.g., [Si/Fe] and [Y/Fe]). Nevertheless, the dispersion of the chemical abundances among our target RSGs is comparable with the individual statistical errors on the abundances. Hence, the procedure is likely to be useful to evaluate the relative difference in chemical abundances among RSGs.
查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
求助全文
约1分钟内获得全文 去求助
来源期刊
Astronomy & Astrophysics
Astronomy & Astrophysics 地学天文-天文与天体物理
CiteScore
10.20
自引率
27.70%
发文量
2105
审稿时长
1-2 weeks
期刊介绍: Astronomy & Astrophysics is an international Journal that publishes papers on all aspects of astronomy and astrophysics (theoretical, observational, and instrumental) independently of the techniques used to obtain the results.
期刊最新文献
MAGIS (Measuring Abundances of red super Giants with Infrared Spectroscopy) project Discovery of a cold giant planet and mass measurement of a hot super-Earth in the multi-planetary system WASP-132 Physical properties of newly active asteroid 2010 LH15 Inelastic H + H3+ collision rates and their impact on the determination of the excitation temperature of H3+ Asteroid detection polar equation calculation and graphical representation
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1