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arXiv · 2508.06075

Radio continuum and \HI 21-cm line observations of a nearby luminous infrared galaxy IRAS 17526+3253

Jianfeng Wu·Zhongzu Wu·Yulia Sotnikova·Bo Zhang·Yongjun Chen·Timur Mufakharov·Zhiqiang Shen
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Abstract

We present results from our EVN and GMRT observations of the radio continuum and spectral line emission in IRAS 17526+3253, along with an analysis of its arcsecond-scale radio properties using archival VLA data. The EVN observations detected radio continuum emission from both the northwest (NW) and southeast (SE) nuclei. The NW nucleus shows two components with high brightness temperatures and radio luminosities, likely indicating the presence of an AGN core and jet. Meanwhile, our EVN observation failed to detect the OH line emission, possibly due to radio frequency interference and/or the emission being partly resolved out and below our detection limit. The multi-band radio spectral energy distribution (SED) deviates from a single power-law at low frequencies, suggesting low-frequency absorption. The GMRT spectral line data reveal both \HI absorption and emission. The \HI emission is diffuse and shows a velocity gradient from about 7500 \kms in the NW to 7800 \kms in the SE nucleus. On larger scales, the \HI emission extends about 4' along the NW-SE direction, with the southeastern extension matching the optical tidal tail. In addition, the weak \HI absorption features show broad line profiles, possibly due to overlapping \HI gas from the two nuclei. The aforementioned results are consistent with properties of intermediate-stage mergers reported in the literature.

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Jianfeng Wu, Zhongzu Wu, Yulia Sotnikova, Bo Zhang, Yongjun Chen, Timur Mufakharov, Zhiqiang Shen. 2025-08-08. Radio continuum and \HI 21-cm line observations of a nearby luminous infrared galaxy IRAS 17526+3253. https://arxiv.org/abs/2508.06075

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