发表机构
Rhodes University; INAF – Osservatorio Astronomico di Cagliari; Laboratoire d’Astrophysique, École Polytechnique Fédérale de Lausanne (EPFL); LIRA, Observatoire de Paris, Université PSL, CNRS; Siena College; INAF – Osservatorio Astronomico di Padova; University of Kansas; Observatoire de Paris, LUX, Collège de France, CNRS, PSL University, Sorbonne University; INAF – Osservatorio Astronomico di Trieste; INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna(罗兹大学; 意大利国家天体物理研究所卡利亚里天文台; 洛桑联邦理工学院天体物理实验室; 巴黎天文台拉格朗日天体物理实验室,巴黎文理研究大学,法国国家科学研究中心; 锡耶纳学院; 意大利国家天体物理研究所帕多瓦天文台; 堪萨斯大学; 巴黎天文台卢克索姆实验室,法兰西公学院,法国国家科学研究中心,巴黎文理研究大学,索邦大学; 意大利国家天体物理研究所的里雅斯特天文台; 意大利国家天体物理研究所博洛尼亚天文与空间科学观测站)
机构由 AI 辅助整理,请以论文原文为准。AI 中文总结
本文通过MeerKAT HI成像研究室女座III丝状结构中星系的HI分布,发现低HI气体分数广泛存在,且约40%非预选HI亏损星系低于标度关系1σ以上,表明气体移除机制涉及局部相互作用与丝状结构本身。
AI 中文摘要
我们展示了MeerKAT对附近室女座III丝状结构中星系的HI观测。该丝状结构的中值距离约为30 Mpc,在约56平方度的天区内延伸约16 Mpc。我们的巡天包含15个指向HI亏损星系的MeerKAT目标点。多分辨率HI成像在8-90角秒范围内,均方根噪声约为0.3 mJy束^-1,达到约4×10^20至约4×10^18原子cm^-2的柱密度。这以约1.2 kpc的分辨率探测星系盘中的HI,并以约13.5 kpc的分辨率探测其外围区域。我们在500-3000 km/s的速度范围内探测到80个源的HI发射;其中大多数是光学上探测到的星系,而10%缺乏确认的对应体。我们还识别出三个在相互作用系统附近没有光学对应体的HI云,可能是在相互作用过程中被位移的。丝状结构中的星系在固定恒星质量下低于场HI气体分数标度关系。关键的是,约40%未按HI亏损选择的星系低于这些关系超过1σ,且更大比例的星系位于平均关系本身之下,表明低HI气体分数在丝状结构中广泛存在,而非仅限于预先选择的亏损星系群。使用不对称参数量化HI形态,我们发现广泛的扰动,且与到丝状结构主轴的投影距离或局部密度没有明显趋势,表明局部相互作用和丝状结构本身的共同作用。本文介绍了巡天描述、星表及HI图谱,为研究室女座III星系中气体移除机制提供了支持。
英文摘要
We present MeerKAT HI observations of galaxies in the nearby Virgo III filament. At a median distance of $\sim30$ Mpc, the filament extends over $\approx16$ Mpc across $\sim56$ deg$^2$. Our survey comprises 15 targeted MeerKAT pointings centred on HI deficient galaxies. Multi-resolution HI imaging at 8-90 arcsec with an rms of $\sim0.3$ mJy beam$^{-1}$ reaches column densities of $\sim4\times10^{20}$ to $\sim4\times10^{18}$ atoms cm$^{-2}$. This probes HI in galaxy discs at $\sim1.2$ kpc resolution and their outskirts at $\sim13.5$ kpc. We detect HI emission from 80 sources within the 500-3000 km/s range; most are optically detected galaxies, while 10 per cent lack confirmed counterparts. We also identify three HI clouds without optical counterparts near an interacting system, possibly displaced during the interaction. Galaxies in the filament lie below the field HI gas-fraction scaling relations at fixed stellar mass. Crucially, $\sim40$ per cent of galaxies not selected for HI deficiency fall more than $1σ$ below these relations, with an even greater fraction lying under the mean relation itself, indicating that the low HI gas fractions are widespread in the filament rather than confined to the pre-selected deficient population. Quantifying HI morphologies using an asymmetry parameter, we find a wide range of disturbances without a clear trend with projected distance to the filament spine or local density, suggesting a combination of local interactions and the filament itself. This paper presents the survey description, catalogue, and HI atlas enabling investigations of gas removal mechanisms in Virgo III galaxies.
Comments14 pages, 12 main figures (34 pages including appendices). Accepted for publication in MNRAS