تقرير
EMPRESS. XII. Statistics on the Dynamics and Gas Mass Fraction of Extremely-Metal Poor Galaxies
| العنوان: | EMPRESS. XII. Statistics on the Dynamics and Gas Mass Fraction of Extremely-Metal Poor Galaxies |
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| المؤلفون: | Xu, Yi, Ouchi, Masami, Isobe, Yuki, Nakajima, Kimihiko, Ozaki, Shinobu, Bouché, Nicolas F., Wise, John H., Emsellem, Eric, Kusakabe, Haruka, Hattori, Takashi, Nagao, Tohru, Chiaki, Gen, Fukushima, Hajime, Harikane, Yuichi, Hayashi, Kohei, Hirai, Yutaka, Kim, Ji Hoon, Maseda, Michael V., Nagamine, Kentaro, Shibuya, Takatoshi, Sugahara, Yuma, Yajima, Hidenobu, Aoyama, Shohei, Fujimoto, Seiji, Fukushima, Keita, Hatano, Shun, Inoue, Akio K., Ishigaki, Tsuyoshi, Kawasaki, Masahiro, Kojima, Takashi, Komiyama, Yutaka, Koyama, Shuhei, Koyama, Yusei, Lee, Chien-Hsiu, Matsumoto, Akinori, Mawatari, Ken, Moriya, Takashi J., Motohara, Kentaro, Murai, Kai, Nishigaki, Moka, Onodera, Masato, Ono, Yoshiaki, Rauch, Michael, Saito, Tomoki, Sasaki, Rin, Suzuki, Akihiro, Takeuchi, Tsutomu T., Umeda, Hiroya, Umemura, Masayuki, Watanabe, Kuria, Yabe, Kiyoto, Zhang, Yechi |
| المصدر: | The Astrophysical Journal, Volume 961, Number 1, January 2024, Page 49-53 |
| سنة النشر: | 2023 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Astrophysics of Galaxies |
| الوصف: | We present demography of the dynamics and gas-mass fraction of 33 extremely metal-poor galaxies (EMPGs) with metallicities of $0.015-0.195~Z_\odot$ and low stellar masses of $10^4-10^8~M_\odot$ in the local universe. We conduct deep optical integral-field spectroscopy (IFS) for the low-mass EMPGs with the medium high resolution ($R=7500$) grism of the 8m-Subaru FOCAS IFU instrument by the EMPRESS 3D survey, and investigate H$\alpha$ emission of the EMPGs. Exploiting the resolution high enough for the low-mass galaxies, we derive gas dynamics with the H$\alpha$ lines by the fitting of 3-dimensional disk models. We obtain an average maximum rotation velocity ($v_\mathrm{rot}$) of $15\pm3~\mathrm{km~s^{-1}}$ and an average intrinsic velocity dispersion ($\sigma_0$) of $27\pm10~\mathrm{km~s^{-1}}$ for 15 spatially resolved EMPGs out of the 33 EMPGs, and find that all of the 15 EMPGs have $v_\mathrm{rot}/\sigma_0<1$ suggesting dispersion dominated systems. There is a clear decreasing trend of $v_\mathrm{rot}/\sigma_0$ with the decreasing stellar mass and metallicity. We derive the gas mass fraction ($f_\mathrm{gas}$) for all of the 33 EMPGs, and find no clear dependence on stellar mass and metallicity. These $v_\mathrm{rot}/\sigma_0$ and $f_\mathrm{gas}$ trends should be compared with young high-$z$ galaxies observed by the forthcoming JWST IFS programs to understand the physical origins of the EMPGs in the local universe. Comment: 18 pages, 9 figures, accepted for publication in ApJ |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.3847/1538-4357/ad06ab |
| URL الوصول: | http://arxiv.org/abs/2303.12467 |
| رقم الأكسشن: | edsarx.2303.12467 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.3847/1538-4357/ad06ab |
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