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Physical Conditions and Star Formation Activity in the Intragroup Medium of Stephan's Quintet

C. K. Xu·N. Lu·J. J. Condon·M. Dopita·R. J. Tuffs
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Abstract

New multi-band observations of the famous compact group of galaxies Stephan's Quintet (SQ) are presented and analyzed. These include far infrared (FIR) images at 60$μm$ and 100$μm$ (ISOPHOT C-100 camera), radio continuum images at 1.4 GHz (VLA B-array) and 4.86 GHz (VLA C-array), and long-slit optical spectrographs (Palomar $200"$ telescope). With these new data, we aim to learn more about the X-ray/radio ridge in the middle of the intragroup medium (IGM) and the IGM starburst SQ-A, both are likely to be caused by the high speed collision ($\sim 900$ km s$^{-1}$) between the intruder galaxy NGC 7318b ($v = 5700$ km s$^{-1}$) and the IGM ($v = 6600$ km s$^{-1}$).

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C. K. Xu, N. Lu, J. J. Condon, M. Dopita, R. J. Tuffs. 2003-06-12. Physical Conditions and Star Formation Activity in the Intragroup Medium of Stephan's Quintet. https://doi.org/10.1086/377445

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