论文标题
星形星系中的2175Å尘埃特征，$ 1.3 \ le z \ le 1.8 $：依赖于恒星质量和特定的恒星形成率
The 2175 Å dust feature in star-forming galaxies at $1.3\le z\le 1.8$: the dependence on stellar mass and specific star formation rate
论文作者
论文摘要
我们使用Zcosmos-Deep-Deep调查中的个人和堆叠的光谱，以$ 1.3 \ le Z \ le 1.8 $介绍505颗恒星形成的主要星系中的宽2175〜吸收特征的直接光谱测量。测量了显着的2175〜2175〜多余的吸收特征，尤其是在复合光谱中。多余的吸收由Drude曲线很好地描述。相对于无特征的Calzetti等人，以$ k（λ）/e（λ）/e（λ）/e（λ）/e（λ）/e（λ）/e（λ）/e（λ）/e（λ）/e（λ）/e（λ）/e表示的凸起幅度。法律，有一个范围$ b_k \ oft0.2 \ textrm { - } 0.8 $。凸起振幅随特定的恒星形成速率（SSFR）而降低，而随着恒星质量的增加，它适度增加。但是，与局部“ Starburst”星系的比较表明，尽管SSFR的SSFR高于本地样品，但高红移主要星系具有更强的凸起特征。将凸起强度绘制在$δ\ log \ mathrm {ssfr} \ equiv \ log \ left（\ mathrm {sfr}/\ mathrm {sfr_ {ms}}} \ right）$相对主序中相对于主序列，但是将两个样本带入了更好的配置。这可能表明，由于超新星和强烈的辐射场破坏了小型碳质晶粒和$ \ sim1〜 \ mathrm {gyrm {gyrm {gyr} $的时光延迟在外观中，因此，这是最近恒星形成历史，这些恒星形成历史可以决定凸起的强度。
We present direct spectroscopic measurements of the broad 2175~Å absorption feature in 505 star-forming main-sequence galaxies at $1.3\le z\le 1.8$ using individual and stacked spectra from the zCOSMOS-deep survey. Significant 2175~Å excess absorption features of moderate strength are measured, especially in the composite spectra. The excess absorption is well described by a Drude profile. The bump amplitude expressed in units of $k(λ)=A(λ)/E(B-V)$, relative to the featureless Calzetti et al. law, has a range $B_k\approx0.2\textrm{--}0.8$. The bump amplitude decreases with the specific star formation rate (sSFR), while it increases moderately with the stellar mass. However, a comparison with local "starburst" galaxies shows that the high-redshift main-sequence galaxies have stronger bump features, despite having a higher sSFR than the local sample. Plotting the bump strength against the $Δ\log\mathrm{sSFR}\equiv \log \left( \mathrm{SFR}/\mathrm{SFR_{MS}}\right)$ relative to the main sequence, however, brings the two samples into much better concordance. This may indicate that it is the recent star formation history of the galaxies that determines the bump strength through the destruction of small carbonaceous grains by supernovae and intense radiation fields coupled with the time delay of $\sim1~\mathrm{Gyr}$ in the appearance of carbon-rich asymptotic giant branch stars.
