Ionized and cold gas components in low surface brightness galaxy AGC 102004
Abstract
We present the integral field spectroscopic observations of ionized gas (H and [{\ion{N}{II}}]) using the PCWI, along with deep CO(2-1) observations by the receiver on JCMT for AGC 102004. The velocity field of H shows an anomalous distribution in the North-Western (NW) disk. The H spectrum is well-fitted by two Gaussian components, and the weak Gaussian component is dominated by the anomalous H in the NW disk. The Gaussian fit center of H emission is offset by +24.2 km s from the systemic velocity obtained from the HI emission. We derive the gas-phase metallicity, 12+log(O/H), using [{\ion{N}{II}}]6583/H ratio as a proxy. The mean value of 12+log(O/H) is 8.30 0.19 over the whole galaxy. The metallicity in the outer disk is lower than the detection limit of 7.72, indicating the metallicity gradient exists in AGC 102004. We speculate a minor/mini-merger event could have happened to the NW disk. CO(2-1) emission has non-detection in AGC 102004, reaching a noise level of 0.33 mK smoothed to 30 km s. The upper limit of molecular gas mass in AGC 102004 is 2.1 10 M with X = 3.0210 cm (K km s). The M/M of AGC 102004 is lower than 0.0037 and lower than that of normal galaxies.
Keywords
Cite
@article{arxiv.2407.18530,
title = {Ionized and cold gas components in low surface brightness galaxy AGC 102004},
author = {Tian-Wen Cao and Zi-Jian Li and Pei-Bin Chen and Chun-Yi Zhang and Gaspar Galaz and Cheng Cheng and Qingzheng Yu and Venu M. Kalari and Junfeng Wang and Hong Wu},
journal= {arXiv preprint arXiv:2407.18530},
year = {2024}
}
Comments
10 pages, 9 figures, Accepted for publication in ApJ