论文标题
在$ z = 0 $：凸起与恒星形成增强的关闭主要合并对
Close Major Merger Pairs at $z=0$: Bulge-to-Total Ratio and Star Formation Enhancement
论文作者
论文摘要
我们介绍了基于\ textsc {galfit}的SDSS r-band图像的2-D分解，对88个关闭主要星系（H-KPAIR）的KS频段选择样品的凸起比（B/T）的研究。我们研究了相互作用诱导的特异性星形成速率的依赖性（$ \ rm ssfr_ {Enh} $）对b/t比的依赖性，以及这种依赖性对螺旋形+螺旋（s+s+s）和螺旋+螺旋++Elliptical（s+Elliptical（s+e）的影响。在H-Kpair中的所有132个螺旋星系中，S+E对的44个显示B/T比44 s+S对中的螺旋形均高，均为$ \ rm b/t = 0.35 \ pm 0.05 $和$ \ rm b/t = 0.26 \ pm 0.26 \ pm 0.03 $。 $ \ rm ssfr_ {eNH} $对b/t比的强大依赖性强，并且只有$ \ rm b/t <0.3 $配对的SFG显示出显着的（$>5σ$）增强。 S+S对配对的SFG显示出类似的趋势，S+S中的许多Disky SFG（$ \ rm B/T <0.1 $）具有强大的SSFR增强功能（$ \ rm SSFR_ {ENH}> 0.7 $ 〜DEX）。对于S+E中的SFG，SSFR没有明确的B/T依赖性，也没有任何B/T仓的显着增强。 S+S中的Disky SFGS在分子气体含量（$ \ rm m_ {h_2}/m_ {star} $）中显示出显着的（$>4σ$），而S+E中的SFGS在任何B/T bin中都没有这样的增强。在对配对星系的任何b/t bin中都可以找到总的气体含量（$ \ rm m_ {gas}/m_ {star} $）的总体气体含量的显着增强。总气体（$ \ rm sfe_ {gas} = sfr/m_ {gas} $）或分子气（$ \ rm sfe_ {h_2} = sfr/m_ {h_2} $）的星形形成效率不取决于b/t的比例。配对SFGS找到的唯一重要的（$>4σ$）SFE增强功能是S+S对的DISKY SFGS的$ \ rm SFE_ {gas} $。
We present a study of the bulge-to-total ratio (B/T) of a Ks-band-selected sample of 88 close major-merger pairs of galaxies (H-KPAIR) based on 2-D decomposition of SDSS r-band images with \textsc{galfit}. We investigate the dependence of the interaction-induced specific star formation rate enhancement ($\rm sSFR_{enh}$) on the B/T ratio, and the effects of this dependence on the differences between star-forming galaxies (SFGs) in spiral+spiral (S+S) and spiral+elliptical (S+E) pairs. Of all 132 spiral galaxies in H-KPAIR, the 44 in S+E pairs show higher B/T than those in the 44 S+S pairs, with means of $\rm B/T = 0.35 \pm 0.05$ and $\rm B/T = 0.26 \pm 0.03$, respectively. There is a strong negative dependence of $\rm sSFR_{enh}$ on the B/T ratio and only paired SFGs with $\rm B/T<0.3$ show significant ($>5σ$) enhancement. Paired SFGs in S+S pairs show a similar trend, and many disky SFGs ($\rm B/T<0.1$) in S+S have strong sSFR enhancements ($\rm sSFR_{enh} > 0.7$~dex). For SFGs in S+E, the sSFR has no clear B/T dependence, nor any significant enhancement in any B/T bin. Disky SFGs in S+S show significant ($>4σ$) enhancement in the molecular gas content ($\rm M_{H_2}/M_{star}$), while SFGs in S+E have no such enhancement in any B/T bin. No significant enhancement on total gas content ($\rm M_{gas}/M_{star}$) is found in any B/T bin for paired galaxies. The star formation efficiency of either the total gas ($\rm SFE_{gas} = SFR/M_{gas}$) or the molecular gas ($\rm SFE_{H_2} = SFR/M_{H_2}$) does not depend on the B/T ratio. The only significant ($>4σ$) SFE enhancement found for paired SFGs is the $\rm SFE_{gas}$ for disky SFGs in S+S pairs.
