We present ALMA Cycle-0 observations of the CO ( 6-5 ) line emission ( rest-frame frequency = 691.473 GHz ) and of the 435 \mu m dust continuum emission in the nuclear region of NGC 34 , a local luminous infrared galaxy ( LIRG ) at a distance of 84 Mpc ( 1 \arcsec = 407 pc ) which contains a Seyfert 2 active galactic nucleus ( AGN ) and a nuclear starburst .
The CO emission is well resolved by the ALMA beam ( 0 \farcs 26 \times 0 \farcs 23 ) , with an integrated flux of f _ { CO~ { } ( 6 - 5 ) } = 1004 ( \pm 151 ) Jy km s ^ { -1 } .
Both the morphology and kinematics of the CO ( 6-5 ) emission are rather regular , consistent with a compact rotating disk with a size of 200 pc .
A significant emission feature is detected on the red-shifted wing of the line profile at the frequency of the H ^ { 13 } CN ( 8 - 7 ) line , with an integrated flux of 17.7 \pm 2.1 ( random ) \pm 2.7 ( sysmatic ) Jy km s ^ { -1 } .
However , it can not be ruled out that the feature is due to an outflow of warm dense gas with a mean velocity of 400 km s ^ { -1 } .
The continuum is resolved into an elongated configuration , and the observed flux corresponds to a dust mass of M _ { dust } = 10 ^ { 6.97 \pm 0.13 } M _ { \sun } .
An unresolved central core ( radius \simeq 50 pc ) contributes 28 \% of the continuum flux and 19 \% of the CO ( 6-5 ) flux , consistent with insignificant contributions of the AGN to both emissions .
Both the CO ( 6-5 ) and continuum spatial distributions suggest a very high gas column density ( \lower 2.0 pt \hbox { $ { > \atop \hbox { \raise 4.0 pt \hbox { $ \sim$ } } } $ } 10 ^ { 4 } M _ % { \sun } pc ^ { -2 } ) in the nuclear region at radius \lower 2.0 pt \hbox { $ { < \atop \hbox { \raise 4.0 pt \hbox { $ \sim$ } } } $ } 100 % pc .