The Fate of the X-Ray Emitting Gas in the The Fate of the X-Ray Emitting Gas in the Early-Type Galaxy NGC 5044Early-Type Galaxy NGC 5044

O’SullivanJeremy Lim

William Forman

Jan Vrtilek

Christine Jones

Ewan O’Sullivan

Francoise Combes

Philippe Salome

Simona Giacintucci

Alastair Edge

Ming Sun

Stephen Hamer

Pasquale Temi

Henrique Schmitt

Youichi Ohyama

William Mathews

Fabrizio Brighenti

Dinh-V Trung

X-Ray Brightest Group in the Sky

Highly Perturbed X-Ray MorphologyHighly Perturbed X-Ray Morphology

Many small cavities inflated by repeated AGN outbursts that essentially blow in the wind.

Sloshing induced cold fronts.

Pcav= 6.5 x 1043 erg s-1 ~ Lx within the central 25 kpc.

tcool= 4 x 107 yr

Mass deposition rate = 5 M yr-1

Raw 0.5-2.0 keV Chandra ACIS images

Radio Properties of the Central AGNRadio Properties of the Central AGN

Many weak AGN outbursts

Pcav for smallest X-ray cavity is 3 x 1041 erg s-1

νLν (230GHz) = 500 νLν (630MHz).

tage = 5 Myr assuming equipartion and a break frequency of 230 GHz.

νLν

(erg

s-1)

GMRT data at 235 MHz

CO(2-1) ALMA ObservationsCO(2-1) ALMA Observations

24 molecular structures detected above 4σ within the central 2.5 kpc.

Mmol = 3 x 105 – 107 M

Mmol (tot) = 5 x 107 M

σv = 15 – 65 km s-1

Linewidths are too broad to be GMCs and are likely Giant Molecular Associations (GMAs).

The GMC filling factor in the few resolved GMAs is 15%.

Comparison of IRAM 30m and ALMA Data at CO(2-1)Comparison of IRAM 30m and ALMA Data at CO(2-1)

IRAM 30m

ALMA

Good agreement between ALMA and IRAM 30m for redshifted CO emission.

The blueshifted IRAM flux is 5 times greater than the blueshifted ALMA flux.

This implies that there is a significant amount of large scale (R>300 pc) blueshifted diffuse CO emission that is resolved-out in the ALMA data.

High Resolution Spectrum of Most Massive High Resolution Spectrum of Most Massive Molecular StructureMolecular Structure

GMA 18 is well fit with a double Gaussian (σv= 5.5 and 37.5 km s-1).

Mmol=1.0 x 107 M

rc=140 pc

α=5σv2rc/GMmol=24

GMA 18 is not gravitationally bound.

GMA 18 is not pressure confined (Pturb > Phot).

GMA 18 will dissipate on a timescale t=2rc/σv=10 Myr.

The linewidth of the narrow line feature is typical of an individual virialized GMC.

CO(2-1) Position-Velocity DiagramCO(2-1) Position-Velocity Diagram

GMAs 13 and 18 are distinct molecular structures

No apparent disk-like structures near the central AGN.

P-V diagram consistent with infall

Kinematics of the Molecular GasKinematics of the Molecular Gas

GMAs 11 and 13 have velocities near the systemic velocity of NGC 5044 far from the AGN and increasing blueshifted velocities near the AGN.

This suggests that these GMAs are falling into the AGN from the far side of the galaxy.

The velocity gradient of GMA 18 is perpendicular to that expected for a disk rotating about the AGN.

CO(2-1) Absorption Feature CO(2-1) Absorption Feature in the AGN Continuumin the AGN Continuum

Fitting a Gaussian profile to the absorption feature gives: <v>=260 km s-1 and σv = 5.2 km s-

1. For comparison, the circular velocity is 325 km s-1.

The linewidth is typical of an individual GMC.

Optical depth at line-center is τ=0.35.

Either 30% of the 230 GHz emission region is covered by an optically thick cloud or the entire 230 GHz emission region is covered by an optically thin cloud.

Assuming the absorption feature is due to a GMC and using a standard linewidth-size relation implies that the 230 GHz emission region is smaller than 50 pc in radius.

Correlations Between the Molecular Gas and Dust Correlations Between the Molecular Gas and Dust and Ha Filamentsand Ha Filaments

A few of the GMAs are obviously correlated with dust.

A few of GMAs trace the dust filament to the NW.

Many GMAs are not associated with dust or Ha emission.

Summary of ALMA ResultsSummary of ALMA Results

Dynamics:

Source of cold gas: Velocity dispersion of the GMAs is 122 km s-1, which is less than the stellar

velocity dispersion of 237 km s-1.

Several GMAs are likely on infalling, nearly radial orbits

No disk-like structures

GMAs have a nearly azimuthially symmetric distribution

Mass deposition rate is 25 times greater than the stellar mass loss rate.

The molecular gas arises from the thermally unstable hot gas.

Supply time is greater than 10 Myr and could be as much as 100 Myr.

For buoyancy to be important the AGN inflated cavities much displace a mass equal to the molecular mass. The displaced mass in the X-ray cavities is only 15% of the molecular mass.

There are no large scale radio jets in NGC 5044.

Molecular structures likely follow ballistic orbits after condensing out of the hot gas.

The GMAs are not gravitationally bound or pressure confined and should disperse on a timescale of approximately 10 Myr.

Summary of ALMA ResultsSummary of ALMA Results

Star Formation:

The observed star formation rate is 0.073 M yr-1 (Werner et al. 2014).

Based on the Kennicutt-Schmidt relation, the total star formation rate from the three best resolved GMAs is 0.03 M yr-1 .

Since these three GMAs comprise 35% of the total molecular mass, there is reasonable good agreement with the observed star formation rate.

The depletion time of the molecular gas due to star formation is 700 Myr.

Assuming one SNeII for each 100 M of gas consumed into stars, implies that SNeII will produce an energy equivalent to 60% of the total turbulent kinetic energy in GMA 18 over its lifetime.