TY - JOUR
T1 - Possible Systematic Rotation in the Mature Stellar Population of a z = 9.1 Galaxy
AU - Tokuoka, Tsuyoshi
AU - Inoue, Akio K.
AU - Hashimoto, Takuya
AU - Ellis, Richard S.
AU - Laporte, Nicolas
AU - Sugahara, Yuma
AU - Matsuo, Hiroshi
AU - Tamura, Yoichi
AU - Fudamoto, Yoshinobu
AU - Moriwaki, Kana
AU - Roberts-Borsani, Guido
AU - Shimizu, Ikkoh
AU - Yamanaka, Satoshi
AU - Yoshida, Naoki
AU - Zackrisson, Erik
AU - Zheng, Wei
N1 - Funding Information:
We thank Renske Smit for a discussion about the method for examining the velocity structure, Masamune Oguri for a discussion about gravitational lensing models, and Yuxing Zhong for a discussion about 3D Baroro . A.K.I., Y.S., and Y.F. are supported by NAOJ ALMA Scientific Research grant No. 2020-16B. T.H. was supported by Leading Initiative for Excellent Young Researchers, MEXT, Japan (HJH02007), and by JSPS KAKENHI grant Nos. 20K22358 and 22H01258. R.S.E. acknowledges funding from the European Research Council under the European Union Horizon 2020 research and innovation program (grant agreement No. 669253). N.L. acknowledges the Kavli foundation. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2015.1.00428.S and ADS/JAO.ALMA#2018.1.00616.S. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ.
Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/7/1
Y1 - 2022/7/1
N2 - We present new observations with the Atacama Large Millimeter/submillimeter Array for a gravitationally lensed galaxy at z = 9.1, MACS1149-JD1. [O iii] 88 μm emission is detected at 10σ with a spatial resolution of 1/40.3 kpc in the source plane, enabling the most distant morphokinematic study of a galaxy. The [O iii] emission is distributed smoothly without any resolved clumps and shows a clear velocity gradient with "V obs/2σ tot = 0.84 ± 0.23, where "V obs is the observed maximum velocity difference and σ tot is the velocity dispersion measured in the spatially integrated line profile, suggesting a rotating system. Assuming a geometrically thin self-gravitating rotation disk model, we obtain Vrot/σV=0.67-0.26+0.73, where V rot and σ V are the rotation velocity and velocity dispersion, respectively, still consistent with rotation. The resulting disk mass of 0.65-0.40+1.37×109 M ⊙ is consistent with being associated with the stellar mass identified with a 300 Myr old stellar population independently indicated by a Balmer break in the spectral energy distribution. We conclude that the most of the dynamical mass is associated with the previously identified mature stellar population that formed at z ∼15.
AB - We present new observations with the Atacama Large Millimeter/submillimeter Array for a gravitationally lensed galaxy at z = 9.1, MACS1149-JD1. [O iii] 88 μm emission is detected at 10σ with a spatial resolution of 1/40.3 kpc in the source plane, enabling the most distant morphokinematic study of a galaxy. The [O iii] emission is distributed smoothly without any resolved clumps and shows a clear velocity gradient with "V obs/2σ tot = 0.84 ± 0.23, where "V obs is the observed maximum velocity difference and σ tot is the velocity dispersion measured in the spatially integrated line profile, suggesting a rotating system. Assuming a geometrically thin self-gravitating rotation disk model, we obtain Vrot/σV=0.67-0.26+0.73, where V rot and σ V are the rotation velocity and velocity dispersion, respectively, still consistent with rotation. The resulting disk mass of 0.65-0.40+1.37×109 M ⊙ is consistent with being associated with the stellar mass identified with a 300 Myr old stellar population independently indicated by a Balmer break in the spectral energy distribution. We conclude that the most of the dynamical mass is associated with the previously identified mature stellar population that formed at z ∼15.
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U2 - 10.3847/2041-8213/ac7447
DO - 10.3847/2041-8213/ac7447
M3 - Article
AN - SCOPUS:85134150074
SN - 2041-8205
VL - 933
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 1
M1 - L19
ER -