论文标题
黑洞和凸起之间的锁定生长会产生其质量关系吗？
Does the lockstep growth between black holes and bulges create their mass relation?
论文作者
论文摘要
最近的研究表明，在膨胀宇宙中，样品平均黑洞（BH）增生率（BHAR）增生率（BHAR）和恒星形成速率（SFR）之间的关系之间的关系之间存在密切的关系，即凸出为主的星系，即“ Lockstep” BH-Bulge的增长。这种关系可能与在当地宇宙中观察到的BH磅质量相关性密切相关。为了了解进一步的BH-bulge协同进化，我们提出了ALMA CO（2-1）或CO（3-2）观察7个恒星形成凸起的星系，z = 0.5-2.5。使用ALMA数据，我们从4个对象中检测到显着（$>3σ$）的CO发射。对于我们的7个星系样本，我们测量（或用上限约束）其CO线通量并估计分子气体质量（$ M_ {GAS} $）。我们还通过建模其光谱能量分布（SED）来估计他们的恒星质量（$ M_ {Star} $）和SFR。使用这些物理属性，我们得出了气体止段时间标准（$ t_ {dep} = m_ {gas}/sfr $），并将它们与凸起/bh增长时间尺度（$ t_ {grow} = m_ {star}/sfr}/sfr \ sim m_ {bh {bh {bh}/bhar $）进行比较。我们的样本通常具有比$ t_ {grow} $短的$ t_ {dep} $，中位数为$ \ gtrsim 4 $，表明在发生大量膨胀/BH增长之前，冷气会耗尽。该结果表明，BH-Bulge Lockstep增长主要是为了维持其质量关系，而不是创建质量关系。我们注意到我们的样本很小，限制为$ z <2.5 $； JWST和ALMA将能够在不久的将来探究更高的红移。
Recent studies have revealed a strong relation between sample-averaged black-hole (BH) accretion rate (BHAR) and star formation rate (SFR) among bulge-dominated galaxies, i.e., "lockstep" BH-bulge growth, in the distant universe. This relation might be closely related to the BH-bulge mass correlation observed in the local universe. To understand further BH-bulge coevolution, we present ALMA CO(2-1) or CO(3-2) observations of 7 star-forming bulge-dominated galaxies at z=0.5-2.5. Using the ALMA data, we detect significant ($>3σ$) CO emission from 4 objects. For our sample of 7 galaxies, we measure (or constrain with upper limits) their CO line fluxes and estimate molecular gas masses ($M_{gas}$). We also estimate their stellar masses ($M_{star}$) and SFRs by modelling their spectral energy distributions (SEDs). Using these physical properties, we derive the gas-depletion timescales ($t_{dep} = M_{gas}/SFR$) and compare them with the bulge/BH growth timescales ($t_{grow} = M_{star}/SFR \sim M_{BH}/BHAR$). Our sample generally has $t_{dep}$ shorter than $t_{grow}$ by a median factor of $\gtrsim 4$, indicating that the cold gas will be depleted before significant bulge/BH growth takes place. This result suggests that the BH-bulge lockstep growth is mainly responsible for maintaining their mass relation, not creating it. We note that our sample is small and limited to $z<2.5$; JWST and ALMA will be able to probe to higher redshifts in the near future.
