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تسجيل مستخدم جديدGemini IFU, VLA, and HST observation of the OH Megamaser Galaxy IRAS17526+3253
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We present a multiwavelength study of the OH megamaser galaxy (OHMG) IRAS17526+3253, based on new Gemini Multi-Object Spectrograph Integral Field Unit (GMOS/IFU) observations, Hubble Space Telescope F814W and H$alpha$+[N{sc ii}] images, and archival 2MASS and 1.49GHz VLA data. The HST images clearly reveal a mid-to-advanced stage major merger whose northwestern and southeastern nuclei have a projected separation of $sim$8.5kpc. Our HST/H$alpha$+[N{sc ii}] image shows regions of ongoing star-formation across the envelope on $sim$10kpc scales, which are aligned with radio features, supporting the interpretation that the radio emission originates from star-forming regions. The measured H$alpha$ luminosities imply that the unobscured star-formation rate is $sim$10-30,M$_{odot}$yr$^{-1}$. The GMOS/IFU data reveal two structures in northwestern separated by 850,pc and by a discontinuity in the velocity field of $sim$~200~km~s$^{-1}$. We associate the blue-shifted and red-shifted components with, respectively, the distorted disk of northwestern and tidal debris, possibly a tail originating in southeastern. Star-formation is the main ionization source in both components, which have SFRs of $sim$2.6-7.9,M$_{odot}$yr$^{-1}$ and $sim$1.5-4.5,M$_{odot}$yr$^{-1}$, respectively. Fainter line emission bordering these main components is consistent with shock ionization at a velocity $sim$200~km~s$^{-1}$ and may be the result of an interaction between the tidal tail and the northwestern galaxys disk. IRAS17526+3253 is one of only a few systems known to host both luminous OH and H$_{2}$O masers. The velocities of the OH and H$_{2}$O maser lines suggest that they are associated with the northwestern and southeastern galaxies, respectively.
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