Quenching by gas compression and consumption
Quenching by gas compression and consumption
复制标题
通过气体压缩和消耗进行淬火
DOI：
10.1051/0004-6361/201834542
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发表时间：
2019
影响因子：
6.5
通讯作者：
T. Falkendal
中科院分区：
文献类型：
--
作者：
A. Man;M. Lehnert;J. Vernet;C. De Breuck;T. Falkendal
本工作的目的是研究活动星系核（AGN）如何影响宿主星系中星星的形成。利用VLT/X-shooter和阿尔马观测资料，详细研究了一个z =2.57的大质量射电星系的恒星形成历史和条件。 深静止帧紫外光谱包含光球吸收线和风特征，表明存在OB型恒星。探测到的最显著的光球特征被用来表征最近的星星形成：无论是瞬时还是连续的恒星形成历史都与Si IIλ1485和SV λ1502吸收的相对强度不一致。相反，在最近的过去，至少发生了两次星星形成的爆发，分别发生在6+1-2百万年前和1.2亿年前。根据阿尔马对[C I] 3 P2 − 3 P1发射的观测，我们推断出H2分子气体的质量为（3.9 ± 1.0）× 1010 M Ω。 分子气体质量仅为恒星质量的13%。结合它的高恒星形成率（1020-170+190 M yr-1），这意味着高恒星形成效率（26 ± 8）Gyr-1和短的耗尽时间（38 ± 12）Myr。 我们将有效的星星形成归因于压缩气体运动，以解释光球线和[C I]追踪的恒星形成气体的适度速度色散（约55 km s−1）。由于射电源的年龄可能非常年轻，我们的研究结果表明，活跃的星星形成消耗了大量的气体，并与活动星系核协同工作，以消除任何残留的分子气体，并最终淬灭大质量星系中的星星形成。
The objective of this work is to study how active galactic nuclei (AGN) influence star formation in host galaxies. We present a detailed investigation of the star-formation history and conditions of a z = 2.57 massive radio galaxy based on VLT/X-shooter and ALMA observations. The deep rest-frame ultraviolet spectrum contains photospheric absorption lines and wind features indicating the presence of OB-type stars. The most significantly detected photospheric features are used to characterize the recent star formation: neither instantaneous nor continuous star-formation history is consistent with the relative strength of the Si IIλ1485 and S Vλ1502 absorption. Rather, at least two bursts of star formation took place in the recent past, at 6+1-2 Myr and ≳20 Myr ago, respectively. We deduce a molecular H2 gas mass of (3.9 ± 1.0) × 1010 M⊙ based on ALMA observations of the [C I] 3P2−3P1 emission. The molecular gas mass is only 13% of its stellar mass. Combined with its high star-formation rate of (1020-170+190 M⊙ yr-1, this implies a high star-formation efficiency of (26 ± 8) Gyr−1 and a short depletion time of (38 ± 12) Myr. We attribute the efficient star formation to compressive gas motions in order to explain the modest velocity dispersions (⩽55 km s−1) of the photospheric lines and of the star-forming gas traced by [C I]. Because of the likely very young age of the radio source, our findings suggest that vigorous star formation consumes much of the gas and works in concert with the AGN to remove any residual molecular gas, and eventually quenching star formation in massive galaxies.
DOI：
10.1088/0004-637x/768/1/74
发表时间：
2012-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
L. Tacconi;R. Neri;R. Genzel;F. Combes;A. Bolatto;M. Cooper;S. Wuyts;F. Bournaud;A. Burkert-
通讯作者：
L. Tacconi;R. Neri;R. Genzel;F. Combes;A. Bolatto;M. Cooper;S. Wuyts;F. Bournaud;A. Burkert-
影响因子：
4.8
作者：
Best, P. N.;Ker, L. M.;Sabater, J.
通讯作者：
Sabater, J.
影响因子：
4.9
作者：
Bisbas, Thomas G.;van Dishoeck, Ewine F.;Zhang, Zhi-Yu
通讯作者：
Zhang, Zhi-Yu