ALMA observations of HCN and HCO+ outflows in the merging galaxy NGC 3256

Abstract

We report ~2" resolution Atacama Large Millimeter/submillimeter Array observations of the HCN(1-0), HCO+(1-0), CO(1-0), CO(2-1), and CO(3-2) lines towards the nearby merging double-nucleus galaxy NGC 3256. We find that the high density gas outflow traced in HCN(1-0) and HCO+(1-0) emission is co-located with the diffuse molecular outflow emanating from the southern nucleus, where a low-luminosity active galactic nucleus (AGN) is believed to be the dominant source of the far-infrared luminosity. On the other hand, the same lines were undetected in the outflow region associated with the northern nucleus, whose primary heating source is likely related to starburst activity without obvious signs of AGN. Both HCO+(1-0)/CO(1-0) line ratio (i.e. dense gas fraction) and the CO(3-2)/CO(1-0) line ratio are larger in the southern outflow (0.20$\pm$0.04 and 1.3$\pm$0.2, respectively) than in the southern nucleus (0.08$\pm$0.01, 0.7$\pm$0.1, respectively). By investigating these line ratios for each velocity component in the southern outflow, we find that the dense gas fraction increases and the CO(3-2)/CO(1-0) line ratio decreases towards the largest velocity offset. This suggests the existence of a two-phase (diffuse and clumpy) outflow. One possible scenario to produce such a two-phase outflow is an interaction between the jet and the interstellar medium, which possibly triggers shocks and/or star formation associated with the outflow.

arXiv comment22 pages, 12 figures, 5 tables, accepted for publication in APJ

References in corpus (77)

• Modeling feedback from stars and black holes in galaxy mergers
• The CO-to-H2 Conversion Factor
• A computer program for fast non-LTE analysis of interstellar line spectra
• Galactic Winds
• The IRAS Revised Bright Galaxy Sample (RBGS)
• A General Theory of Turbulence-Regulated Star Formation, From Spirals to ULIRGs
• The Star Formation Rate and Dense Molecular Gas in Galaxies
• Massive Molecular Outflows and Evidence for AGN Feedback from CO Observations
• Calibrating Extinction-Free Star Formation Rate Diagnostics with 33GHz Free-Free Emission in NGC6946
• Quasar feedback revealed by giant molecular outflows
• AGN wind scaling relations and the co-evolution of black holes and galaxies
• The physics of galactic winds driven by active galactic nuclei
• Clearing Out a Galaxy
• Star Formation Rates in Molecular Clouds and the Nature of the Extragalactic Scaling Relations
• The multi-phase winds of Markarian 231: from the hot, nuclear, ultra-fast wind to the galaxy-scale, molecular outflow
• The Relation Between Quasar and Merging Galaxy Luminosity Functions and the Merger-Induced Star Formation Rate of the Universe
• Galaxy-Wide Shocks in Late-Merger Stage Luminous Infrared Galaxies
• Jet-induced star formation in gas-rich galaxies
• Star formation in a galactic outflow
• The fast molecular outflow in the Seyfert galaxy IC5063 as seen by ALMA
• Detection of HCN, HCO+ and HNC in the Mrk231 molecular outflow - Dense molecular gas in the AGN wind
• Variations in the Star Formation Efficiency of the Dense Molecular Gas across the Disks of Star-Forming Galaxies
• The physics and the structure of the quasar-driven outflow in Mrk 231
• Galaxy-wide outflows: cold gas and star formation at high speeds
• Jet acceleration of the fast molecular outflows in the Seyfert galaxy IC5063
• The Spectral Energy Distribution of CO lines in M82
• The origin of fast molecular outflows in quasars: molecule formation in AGN-driven galactic winds
• CN and HNC Line Emission in IR Luminous Galaxies
• High resolution observations of HCN and HCO+ J=3-2 in the disk and outflow of Mrk231 -Detection of vibrationally excited HCN in the warped nucleus
• Galaxy-Scale Outflows Driven by Active Galactic Nuclei
• Dense Molecular Gas Tracers in the Outflow of the Starburst Galaxy NGC 253
• HCN versus HCO+ as dense molecular gas mass tracer in Luminous Infrared Galaxies
• P-Cygni Profiles of Molecular Lines toward Arp 220 Nuclei
• Galaxy mergers on a moving mesh: a comparison with smoothed-particle hydrodynamics
• Radiation pressure and absorption in AGN: results from a complete unbiased sample from Swift
• The Role of Galactic Winds on Molecular Gas Emission from Galaxy Mergers
• High-resolution imaging of the molecular outflows in two mergers: IRAS17208-0014 and NGC1614
• Molecules in galaxies
• A Luminous Infrared Merger with Two Bipolar Molecular Outflows: ALMA and SMA Observations of NGC 3256
• Tracing the extreme interplay between radio jets and the ISM in IC5063
• Herschel-SPIRE Imaging Spectroscopy of Molecular Gas in M82
• ALMA reveals optically thin, highly excited CO gas in the jet-driven winds of the galaxy IC5063
• Fast cold gas in hot AGN outflows
• ALMA [CI]${}^3{P}_1{-}^3{P}_0$ observations of NGC6240: a puzzling molecular outflow, and the role of outflows in the global ${\alpha }_{\mathrm{CO}}$ factor of (U)LIRGs
• Fast, Collimated Outflow in the Western Nucleus of Arp 220
• The Mrk 231 molecular outflow as seen in OH
• Water vapor in nearby infrared galaxies as probed by Herschel
• Can AGN feedback-driven star formation explain the size evolution of massive galaxies?
• Do AGN outflows quench or enhance star formation?
• Optical Depth Estimates and Effective Critical Densities of Dense Gas Tracers in the Inner Parts of Nearby Galaxy Discs
• Spatially resolved cold molecular outflows in ULIRGs
• ALMA Cycle 1 Observations of the HH46/47 Molecular Outflow: Structure, Entrainment and Core Impact
• Chemical Features in the Circumnuclear Disk of the Galactic Center
• Galaxy-scale AGN Feedback - Theory
• High resolution mapping of CO(1-0) in NGC6240
• NGC6240: extended CO structures and their association with shocked gas
• ALMA Multi-line Observations of the IR-bright Merger VV 114
• A radio jet drives a molecular and atomic gas outflow in multiple regions within one square kiloparsec of the nucleus of the nearby galaxy IC5063
• Resolving the Bright HCN(1-0) Emission toward the Seyfert 2 Nucleus of M51: Shock Enhancement by Radio Jets and Weak Masing by Infrared Pumping?
• Outflow of hot and cold molecular gas from the obscured secondary nucleus of NGC3256: closing in on feedback physics
• ALMA Astrochemical Observations of the Infrared-Luminous Merger NGC 3256
• Herschel spectroscopic observations of the compact obscured nucleus in Zw 049.057
• On the Formation of Molecular Clumps in QSO Outflows
• Radio Emission Associated with Ultraluminous X-ray Sources in the Galaxy Merger NGC 3256
• Dense Gas Fraction and Star Formation Efficiency Variations in the Antennae Galaxies
• Evidence for a chemically differentiated outflow in Mrk 231
• Around the Ring We Go: The Cold, Dense Ring of Molecular Gas in NGC 1614
• Imaging the Molecular Outflows of the Prototypical ULIRG NGC 6240 with ALMA
• Stellar Signatures of AGN Jet Triggered Star Formation
• CSO and CARMA Observations of L1157. II. Chemical Complexity in the Shocked Outflow
• Infrared and X-Ray Evidence of an AGN in the NGC 3256 Southern Nucleus
• Sub-arcsecond imaging of the water emission in Arp 220
• An infrared study of the double nucleus in NGC3256
• Investigating the Relation between CO (3-2) and Far Infrared Luminosities for Nearby Merging Galaxies Using ASTE
• A comparison of shock-cloud and wind-cloud interactions: The longer survival of clouds in winds
• Spatially-resolved Radio-to-Far-infrared SED of the Luminous Merger Remnant NGC 1614 with ALMA and VLA
• First detection of the 448 GHz H2O transition in space

Cited by in corpus (19)

• Cool Outflows in Galaxies and their Implications
• SUPER-II: Spatially resolved ionized gas kinematics and scaling relations in z~2 AGN host galaxies
• Star formation and nuclear activity in luminous infrared galaxies: An infrared through radio review
• The ALMA Discovery of the Rotating Disk and Fast Outflow of Cold Molecular Gas in NGC 1275
• BASS XXXI: Outflow scaling relations in low redshift X-ray AGN host galaxies with MUSE
• Frequency and nature of central molecular outflows in nearby star-forming disk galaxies
• Incorporating Astrochemistry into Molecular Line Modelling via Emulation
• Highly turbulent gas on GMC-scales in NGC 3256, the nearest luminous infrared galaxy
• Planck's Dusty GEMS. VIII. Dense-gas reservoirs in the most active dusty starbursts at z~3
• Star formation traced by optical and millimeter hydrogen recombination lines and free-free emissions in the dusty merging galaxy NGC 3256 -- MUSE/VLT and ALMA synergy
• Excitation and acceleration of molecular outflows in LIRGs: The extended ESO 320-G030 outflow on 200-pc scales
• Planck Cold Clumps in the lambda Orionis Complex. III. A chemical probe of stellar feedback on cores in the lambda Orionis cloud
• A Comparison of Star-Forming Clumps and Tidal Tails in Local Mergers and High Redshift Galaxies
• Observed CN and HCN intensity ratios exhibit subtle variations in extreme galaxy environments
• APEX and NOEMA observations of H${}_2$S in nearby luminous galaxies and the ULIRG Mrk~231 -- Is there a relation between dense gas properties and molecular outflows?
• The isothermal evolution of a shock-filament interaction
• HCN (1-0) opacity of outflowing gas in Arp 220W
• Origins of the shocks in high-mass starless clump candidates
• Surveying the Whirlpool at Arcseconds with NOEMA (SWAN) II: Survey design and observations