VNGS science highlight: PDR models of M51[C

II]/

[OI]

63

([CII]+[OI]63)/FTIR

Similar gas properties in arm and interarm regions.

Higher densities and stronger radiation fields in center

T. Parkin et al., 2013, ApJ

M51: Gas properties from far-M51: Gas properties from far-infrared forbidden linesinfrared forbidden lines

L(TIR) [CII] 158 microns• PACS raster maps of center of M51• plus SPIRE-FTS map of [NII] 205 micron line

T. Parkin et al., 2013, ApJ

M51: Gas properties from far-M51: Gas properties from far-infrared forbidden linesinfrared forbidden lines

[OI] 63 microns [NII] 122 microns• PACS raster maps of center of M51• Plus [OIII] 88 micron and [OI] 145 micron in strip

T. Parkin et al., 2013, ApJ

Compare to models of Photon Compare to models of Photon Dominated Regions (PDRs)Dominated Regions (PDRs)

• Use models from Kaufman et al. 1999, ApJ– Two free parameters: strength of UV radiation field (Go) and

gas density (n)

• Some [CII] emission comes from ionized gas --> remove• [OI] high optical depth --> correct

T. Parkin et al., 2013, ApJ

Observed Corrected

Compare to PDR modelsCompare to PDR models

Higher densities and stronger radiation fields in center

Similar gas properties in arm and interarm regions

T. Parkin et al., 2013, ApJ

NucleusCenterArmInterarm

([CII]+[OI]63)/FTIR

[CII

]/[O

I]63

The Antennae (NGC 4038/9)The Antennae (NGC 4038/9)

Left figure: Wilson et al. 2000, ApJ;HST image: Whitmore et al. 1999, AJ

Schirm et al., 2014, ApJ

CO J=6-5 map with FTS

Spectral Line Energy Spectral Line Energy Distributions at three positionsDistributions at three positions

[CI] lines

CO lines

Note: true intensity (not renormalized)

J(upper)Schirm et al., 2014, ApJ

Physical properties of the Physical properties of the cold and warm gascold and warm gas

• Temperature versus density (left) and pressure (right)

• Blue = cold gas• Red = warm gas• CO+CI solutions

• Column density versus density (left) and pressure (right)

Schirm et al., 2014, ApJ

NGC 4125: an unusual elliptical galaxyNGC 4125: an unusual elliptical galaxy

• Dust mass 6x106 Mo but only upper limits to HI and CO• submillimeter continuum follows r1/4 profile similar to stars• Dust to stellar mass ratio 3x10-5 Mo similar to other ellipticals

• Dust in this galaxy produced internally from evolved stars with gas transitioning rapidly to temperatures > 104 K

(Wilson et al., 2013, ApJL)

250 m contours on K-band image

Priorities for future work• Continue analysis of FTS data

– M83: Wu et al. 2014 (referee report received)– M51: (Schirm et al., analysis underway)– Other galaxies: Cen A, NGC 891

• Continue analysis of PACS spectroscopy– NGC 891 (Hughes et al., first draft circulated)– Other galaxies: NGC 5195, M81, NGC 2403, M83

(outer strip only)

• Overview/cross-galaxy comparison paper(s)? Dust? Gas? Combined?

• Note: not clear who will work on remaining data …

VNGS Publications since June, 2013

• T. Parkin et al., 2014, “The physical characteristics of the gas in the disk of Centaurus A using the Herschel Space Observatory”, ApJ, in press

• T. Hughes et al., “A resolved analysis of cold dust and gas in the nearby edge-on spiral NGC 891”, 2014, A&A

• M. Schirm et al., “Herschel-SPIRE Fourier Transform Spectrometer Observations of Excited CO and [C I] in the Antennae (NGC 4038/39): Warm and Cold Molecular Gas”, 2014, ApJ

• C. Wilson et al., “Cold Dust but Warm Gas in the Unusual Elliptical Galaxy NGC 4125”, 2013, ApJ

• T. Parkin et al., “Regional Variations in the Dense Gas Heating and Cooling in M51 from Herschel Far-infrared Spectroscopy”, 2013, ApJ

• K. Foyle et al., “Star formation and dust heating in the FIR bright sources of M83”, 2013, MNRAS

Other plans and analysis techniques

• PACS spectroscopy cubes fully processed and ready to submit to the Herschel archive

• Foyle et al. (2013) paper on M83 applied getsources to an extragalactic source (see also Natale, Foyle et al. 2014 for M33)

• Analysis of FTS intermediate sampled maps underway using source-correction tool from Wu et al. (2013) in hipe

• Last data delivery will be FTS spectroscopy– Need to think about what products it makes sense

to deliver beyond the basic processed hipe data