论文标题
TEV Extreme Blazar 2WHSP J073326.7+515354的光谱表征
Optical spectral characterization of the the TeV extreme blazar 2WHSP J073326.7+515354
论文作者
论文摘要
相对论喷气机的发射通常超过了他们的宿主星系，挑战了他们的距离和恒星种群的特征。在极端的大麻（EHBL）的情况下，情况变得更加有利，为此，相对论喷气机的大部分发射以较高的能量排放，从而揭示了宿主星系的光学发射。距离测定对于研究大麻的固有特征的研究至关重要，特别是是为了估计由于与外层次背景光的相互作用而导致的固有伽马射线光谱扭曲。在这项工作中，我们报告了2WHSP 〜J073326.7+515354在光频段中的宿主星系的性质，这是在TEV Energies上检测到的少数EHBL之一。我们介绍了源距离的第一个测量，$ \ mathrm {z} = 0.06504 \ pm0.00002 $（速度分散$σ= 237 \ pm 9 \，\ mathrm {km s^{ - 1}}} $）。我们还对其宿主星系的恒星人群进行了详细研究。我们发现，大规模加权平均恒星年龄为$ 11.72 \ pm0.06 \，\ mathrm {gyr} $和平均金属性$ [m/h] = 0.159 \ pm 0.016 $。此外，还对宿主星系进行了形态学研究。表面亮度分布是通过主要的经典凸起的组成（$ r_e = 3.77 \ pm1 \ arcsec $或等效地4.74〜kpc）加上与活性核相对应的未分辨源的组成来建模的。使用与速度分散的质量关系和凸起的绝对大小估算黑洞质量，从而得到可比的结果：$（4.8 \ pm0.9）\ times10^8 \，m _ {\ odot} $和$（3.7 \ pm1.0）\ pm1.0 \ pm1.0）
The emission from the relativistic jets in blazars usually outshines their host galaxies, challenging the determination of their distances and the characterization of the stellar population. The situation becomes more favorable in the case of the extreme blazars (EHBLs), for which the bulk of the emission of the relativistic jets is emitted at higher energies, unveiling the optical emission from the host galaxy. The distance determination is fundamental for the study of the intrinsic characteristics of the blazars, especially to estimate the intrinsic gamma-ray spectra distorted due to the interaction with the Extragalactic Background Light. In this work we report on the properties of 2WHSP~J073326.7+515354 host galaxy in the optical band, which is one of the few EHBLs detected at TeV energies. We present the first measurement of the distance of the source, $\mathrm{z}=0.06504\pm0.00002$ (velocity dispersion $σ=237 \pm 9\,\mathrm{km s^{-1}}$). We also perform a detailed study of the stellar population of its host galaxy. We find that the mass-weighted mean stellar age is $11.72\pm0.06\,\mathrm{Gyr}$ and the mean metallicity $[M/H]=0.159 \pm 0.016$. In addition, a morphological study of the host galaxy is also carried out. The surface brightness distribution is modelled by a composition of a dominant classical bulge ($R_e=3.77\pm1\arcsec $ or equivalently 4.74~kpc) plus an unresolved source which corresponds to the active nucleus. The black hole mass is estimated using both the mass relation with the velocity dispersion and the absolute magnitude from the bulge yielding comparable results: $(4.8\pm0.9)\times10^8\,M_{\odot}$ and $(3.7\pm1.0)\times10^8\,M_{\odot}$, respectively.
