论文标题
本地卷矮kk242：径向速度，SF区域和金属性
Local Volume dwarf KK242: radial velocity, SF region, and metallicity
论文作者
论文摘要
KK242是位于空隙环境中的过渡类型的LV矮人。 Koda等。关于与SCD Galaxy NGC6503的联系的明确指示。这意味着〜6.3 MPC的KK242的距离及其M_B = -10.5 mag。它的径向速度从Effelsberg射频\ HI \观测值中得知，但揭示了NGC6503，DV〜400 km/s的差异。如果是真实的，那么这个事实意味着对其起源的实质性约束。为了清除KK242径向速度的问题，我们使用了其微弱的恒星形成（SF）复合物的SAO 6-m望远镜光谱获得。在两个相邻的紧凑区域（南部和北）检测到H-α和H-beta的发射，分隔〜2“（〜60 pc）。它们的平均径向速度为v_hel = -66 km/s，〜100 km/s，低于NGC6503的距离。 KK242，在SF复合体中，令人兴奋的热星，可能的BHEB和Rheb恒星以及一个超新星残留物，我们根据其气体金属性的可能范围来解决。 12+log（O/h）的值〜7.35 +/- 0.18 DEX，预期用于剥离的void dirr Galaxy。
KK242 is a LV dwarf of transition type residing in the void environment. Koda et al. present clear indications on its connection with Scd galaxy NGC6503. This implies the distance to KK242 of ~6.3 Mpc and its M_B = -10.5 mag. Its radial velocity, known from the Effelsberg radio telescope \HI\ observations, reveals, however, the difference with that of NGC6503, dV ~ 400 km/s. If real, this fact implies the substantial constraints on its origin. To clear-up the issue of KK242 radial velocity, we obtained with the SAO 6-m telescope spectra of its faint star-forming (SF) complex. H-alpha and H-beta emission is detected in two adjacent compact regions, the southern and northern, separated by ~2" (~60 pc). Their mean radial velocity is V_hel = -66 km/s, ~100 km/s lower than that of NGC6503. We use the HST Legacy Archive images and photometry of individual stars from the Extragalactic Distance Database, available for KK242, to identify in the SF complex the exciting hot stars, the probable BHeB and RHeB stars and a supernova remnant. We address, based on the possible range of its gas metallicity, the probable evolutionary paths of KK242. Using package Cloudy and parameters of the exciting B0V stars, we conclude that the observed flux ratio of [Sii] doublet to H-alpha is consistent with the value of 12+log(O/H) ~7.35+/-0.18 dex, expected for a stripped void dIrr galaxy.
