اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدThe molecular outflow in NGC253 at a resolution of two parsecs
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We present 0.15 (~2.5pc) resolution ALMA CO(3-2) observations of the starbursting center in NGC253. Together with archival ALMA CO(1-0) and CO(2-1) data we decompose the emission into a disk and non-disk component. We find ~7-16% of the CO luminosity to be associated with the non-disk component ($1.2-4.2 times 10^7$ K km s$^{-1}$ pc$^2$). The total molecular gas mass in the center of NGC253 is $sim 3.6 times 10^8$ M$_odot$ with $sim 0.5 times 10^8$ M$_odot$ (~15%) in the non-disk component. These measurements are consistent across independent mass estimates through three CO transitions. The high-resolution CO(3-2) observations allow us to identify the molecular outflow within the non-disk gas. Using a starburst conversion factor, we estimate the deprojected molecular mass outflow rate, kinetic energy and momentum in the starburst of NGC253. The deprojected molecular mass outflow rate is in the range ~14-39 M$_odot$ yr$^{-1}$ with an uncertainty of 0.4dex. The large spread arises due to different interpretations of the kinematics of the observed gas while the errors are due to unknown geometry. The majority of this outflow rate is contributed by distinct outflows perpendicular to the disk, with a significant contribution by diffuse molecular gas. This results in a mass loading factor $eta = dot{M}_mathrm{out} / dot{M}_mathrm{SFR}$ in the range $eta sim 8-20$ for gas ejected out to ~300pc. We find the kinetic energy of the outflow to be $sim 2.5-4.5 times 10^{54}$ erg and ~0.8dex typical error which is ~0.1% of the total or ~8% of the kinetic energy supplied by the starburst. The outflow momentum is $4.8-8.7 times 10^8$ M$_odot$ km s$^{-1}$ (~0.5dex error) or ~2.5-4% of the kinetic momentum released into the ISM by feedback. The unknown outflow geometry and launching sites are the primary source of uncertainty in this study.
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We present ALMA observations of the CO(2-1) and CO(3-2) molecular gas transitions and associated (sub)-mm continua of the nearby Seyfert 1.5 galaxy NGC3227 with angular resolutions 0.085-0.21 (7-15pc). On large scales the cold molecular gas shows cir
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Feedback in the form of mass outflows driven by star formation or active galactic nuclei is a key component of galaxy evolution. The luminous infrared galaxy Zw 049.057 harbours a compact obscured nucleus with a possible far-IR signature of outflowin
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We have used the Australia Telescope Compact Array (ATCA) to observe the 36.2-GHz class I methanol maser emission towards NGC253 and find that it is located at the interface between the nuclear ring and both ends of the galactic bar. This is thought
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We present radio and infrared observations indicating on-going star formation activity inside the $sim2-5$ pc circumnuclear ring at the Galactic center. Collectively these measurements suggest a continued disk-based mode of on-going star formation ha
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