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تسجيل مستخدم جديدMolecular Gas Outflow in the Starburst Galaxy NGC 1482
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Galactic winds are essential to regulation of star formation in galaxies. To study the distribution and dynamics of molecular gas in a wind, we imaged the nearby starburst galaxy NGC 1482 in CO ($J=1rightarrow0$) at a resolution of 1 ($approx100$ pc) using the Atacama Large Millimeter/submillimeter Array. Molecular gas is detected in a nearly edge-on disk with a radius of 3 kpc and a biconical outflow emerging from the central 1 kpc starburst and extending to at least 1.5 kpc perpendicular to the disk. In the outflow, CO gas is distributed approximately as a cylindrically symmetrical envelope surrounding the warm and hot ionized gas traced by H$alpha$ and soft X-rays. The velocity, mass outflow rate, and kinetic energy of the molecular outflow are $v_mathrm{w}sim100~mathrm{km~s^{-1}}$, $dot{M}_mathrm{w}sim7~M_odot~mathrm{yr}^{-1}$, and $E_mathrm{w}sim7times10^{54}~mathrm{erg}$, respectively. $dot{M}_mathrm{w}$ is comparable to the star formation rate ($dot{M}_mathrm{w}/mathrm{SFR}sim2$) and $E_mathrm{w}$ is $sim1%$ of the total energy released by stellar feedback in the past $1times10^7~mathrm{yr}$, which is the dynamical timescale of the outflow. The results indicate that the wind is starburst driven.
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