Dragan Salak

GAS DYNAMICS AND OUTFLOW IN THE BARRED STARBURST GALAXY NGC 1808 REVEALED WITH ALMA

NGC 1808 is a nearby barred starburst galaxy with an outflow from the nuclear region. To study the inflow and outflow processes related to star formation and dynamical evolution of the galaxy, we have carried out \(^{12}\)CO (\(J=1-0\)) mapping observations of the central \(r\sim4\) kpc of NGC 1808 using the Atacama Large Millimeter/submillimeter Array (ALMA). Four distinct components of molecular gas are revealed at high spatial resolution of 2\arcsec (\(\sim100\) pc): (1) a compact (\(r<200\) pc) circumnuclear disk (CND), (2) \(r\sim500\) pc ring, (3) gas-rich galactic bar, and (4) spiral arms. Basic geometric and kinematic parameters are derived for the central 1-kpc region using tilted-ring modeling. The derived rotation curve reveals multiple mass components that include (1) a stellar bulge, (2) nuclear bar and molecular CND, and (3) unresolved massive (\(\sim10^7~M_\sun\)) core. Two systemic velocities, 998 km s\(^{-1}\) for the CND and 964 km s\(^{-1}\) for the 500-pc ring, are revealed, indicating a kinematic offset. The pattern speed of the primary bar, derived by using a cloud-orbit model, is \(56\pm11\) km s\(^{-1}\) kpc\(^{-1}\). Non-circular motions are detected associated with a nuclear spiral pattern and outflow in the central 1-kpc region. The ratio of the mass outflow rate to the star formation rate is \(\dot{M}_\mathrm{out}/SFR\sim0.2\) in the case of optically thin CO (1-0) emission in the outflow, suggesting low efficiency of star formation quenching.

Hot ammonia in the center of the Seyfert 2 galaxy NGC 3079

We present the results of ammonia observations toward the center of NGC 3079. The NH3(J, K) = (1, 1) and (2, 2) inversion lines were detected in absorption with the Tsukuba 32-m telescope, and the NH3(1,1) through (6,6) lines with the VLA, although the profile of NH3(3,3) was in emission in contrast to the other transitions. The background continuum source, whose flux density was ~50 mJy, could not be resolved with the VLA beam of ~ ~ 175 K, tracing hot gas associated with the interaction of the fast nuclear outflow with dense molecular material around the nucleus.

Evolution of Molecular Clouds in the Superwind Galaxy NGC 1808 Probed by ALMA Observations

ALMA imaging of the cold molecular medium in the nearby starburst galaxy NGC 1808 is presented. The observations reveal the distribution of molecular gas, traced by

Discovery of H2O megamasers in obscured active galactic nuclei

^{12}

A Multi-Line Ammonia Survey of the Galactic Center Region with the Tsukuba 32-m Telescope - I. Observations and Data

CO (1-0) and

ALMA multiline observations toward the central region of NGC 613

^{12}

Hot gas in the center of the Seyfert galaxy NGC 3079

CO (3-2), and continuum (93 and 350 GHz) across the central 1 kpc starburst region at high resolution of

Large-Field CO (J = 1→0) Observations of the Starburst Galaxy M 82

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CO Multi-line Imaging of Nearby Galaxies (COMING). I. Physical properties of molecular gas in the barred spiral galaxy NGC 2903

arcsec. A molecular gas torus (radius

CO (J = 3 → 2) observations of the starburst galaxy NGC 1808 with ASTE

\sim30