arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2601.06968astro-ph.GA
收藏

宇宙大爆炸后2.2亿年星形成星系中的氮丰度并未升高

Nitrogen abundances in star-forming galaxies 2.2 Gyr after the Big Bang are not elevated

University of Geneva(日内瓦大学);CNRS, IRAP(法国国家科学研究中心,天体物理研究所);Bogolyubov Institute for Theoretical Physics, National Academy of Sciences of Ukraine(乌克兰国家科学院博戈留博夫理论物理研究所);California Institute of Technology(加州理工学院);University of California, Riverside(加利福尼亚大学河滨分校);University of California, Los Angeles(加利福尼亚大学洛杉矶分校);Institute of Science and Technology Austria (ISTA)(奥地利科学技术研究院);The University of Texas at Austin(德克萨斯大学奥斯汀分校);University of Edinburgh(爱丁堡大学);Johns Hopkins University(约翰斯·霍普金斯大学)
D. Schaerer, Y. I. Izotov, R. Marques-Chaves, C. C. Steidel, N. Reddy, A. E. Shapley, S. Mascia, J. Chisholm, S. R. Flury, N. Guseva, T. Heckman, A. Henry, A. K… 展开作者

D. Schaerer, Y. I. Izotov, R. Marques-Chaves, C. C. Steidel, N. Reddy, A. E. Shapley, S. Mascia, J. Chisholm, S. R. Flury, N. Guseva, T. Heckman, A. Henry, A. K. Inoue, I. Jung, H. Kusakabe, K. Mawatari, P. Oesch, G. Oestlin, L. Pentericci, N. Roy, A. Saldana-Lopez, R. Sato, E. Vanzella, A. Verhamme, B. Wang

AI总结:

研究利用JWST光谱确定了z≈3星系的氮氧比,发现其与低红移星系无显著差异,表明氮氧比未随红移演化。

摘要:

利用JWST的深场中等分辨率光谱,对LyC22巡天中典型的恒星形成星系(Lyman break galaxies和Lyman-α发射体)进行研究,通过直接方法基于auroral [OIII]4363线检测确定了25个对象的N、O和Ne相对于H的星云丰度。我们的测量提高了z≈2-4范围内使用统一方法确定N/O的准确性。观测到的N/O比值和散射与低红移星系和HII区域在相同金属丰度范围内的比值无显著差异,表明典型星系在宇宙时间的显著部分内N/O比未随红移演化。此外,我们还发现z≈3星系在BPT图中的偏移与低红移Lyman连续谱巡天(LzLCS)中的星系相比,与SDSS星系的平均值相比,偏移并非由增强的氮丰度引起。我们的结果为未来研究更高红移下N和O的演化奠定了基础。

英文摘要:

Using deep medium-resolution JWST rest-optical spectra of a sample of typical star-forming galaxies (Lyman break galaxies and Lyman-$α$ emitters) from the LyC22 survey at $z \sim 3$, we determined the nebular abundances of N, O, and Ne relative to H for a subsample of 25 objects with the direct method, based on auroral [OIII]4363 line detections. Our measurements increases the number of accurate N/O determinations at $z \sim 2-4$ using a homogeneous approach. We found a mean value of $\log({\rm N/O})=-1.29^{+0.25}_{-0.21} $ over a metallicity range 12+log(O/H)=7.5 to 8.44. The observed N/O ratio and scatter are indistinguishable from that observed in low-z galaxies and HII regions over the same metallicity range, showing thus no redshift evolution of N/O for typical galaxies over a significant fraction of cosmic time. We also show that typical $z \sim 3$ galaxies show a similar offset in the BPT diagram as galaxies from the low-z Lyman Continuum Survey (LzLCS), when compared to the average of SDSS galaxies, and show that this offset is not due to enhanced nitrogen abundances. Our results establish a basis for future studies of the evolution of N and O at higher redshifts.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑