<i>HERschel</i>Observations of Edge-on Spirals (HEROES)

Verstappen, J.; Fritz, J.; Baes, M.; Smith, M.; Allaert, F.; Bianchi, S.; Blommaert, J. A. D. L.; Geyter, Gert De; Looze, I. De; Gentile, Gianfranco; Gordon, K. D.; Holwerda, Benne W.; Viaene, S.; Xilouris, E. M.

doi:10.1051/0004-6361/201220733

Cited by 48 publications

(82 citation statements)

References 94 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The mean value determined from all these data is z dust /r 25 1/99, consistent with z CO /r 25 ∼ 1/101 determined by Yim et al (2011) in NGC 891. A similar value (z dust /r 25 = 1/108) has been also obtained from the direct analysis of seven edge-on galaxies observed by Herschel (Verstappen et al 2013). Since r 24.5 (g) r 25 (B), we assume z CO /r 25 (B) = z CO /r 24.5 (g) = 1/100.…”

Section: Extrapolation Of the Central Beamsupporting

confidence: 80%

Cold gas properties of theHerschelReference Survey

Boselli

Cortese

Boquien

2014

A&A

149

257

View full text Add to dashboard Cite

We present new 12 CO(1-0) observations of 59 late-type galaxies belonging to the Herschel Reference Survey (HRS), a complete K-band-selected, volume-limited (15 D 25 Mpc) sample of nearby galaxies spanning a wide range in morphological type and luminosity. We studied different recipes to correct single-beam observations of nearby galaxies of different sizes and inclinations for aperture effects. This was done by comparing single-beam and multiple-beam observations along the major axis, which were corrected for aperture effects using different empirical or analytical prescriptions, to integrated maps of several nearby galaxies, including edge-on systems observed by different surveys. The resulting recipe is an analytical function determined by assuming that late-type galaxies are 3D exponentially declining discs with a characteristic scale length r CO = 0.2 r 24.5 , where r 24.5 is the optical, g-(or B-) band isophotal radius at the 24.5 mag arcsec −2 (25 mag arcsec −2 ), as well as a scale height z CO = 1/100 r 24.5 . Our new CO data are then combined with those available in the literature to produce the most updated catalogue of CO observations for the HRS, now including 225 out of the 322 galaxies of the complete sample. The 3D exponential disc integration is applied to all the galaxies of the sample to measure their total CO fluxes, which are later transformed into molecular gas masses using a constant and a luminosity-dependent X CO conversion factor. We also collect Hi data for 315 HRS galaxies from the literature and present it in a homogenised form.

show abstract

Section: Extrapolation Of the Central Beamsupporting

confidence: 80%

Cold gas properties of theHerschelReference Survey

Boselli

Cortese

Boquien

2014

A&A

149

257

View full text Add to dashboard Cite

show abstract

“…This suggests that UGC 4277 has a rather clumpy H  disk. Similarly, the FIR morphology, especially in the PACS bands, suggests that the dust disk of UGC 4277 is also rather irregular (Verstappen et al 2013). …”

Section: The Datamentioning

confidence: 93%

“…This will extend the recent study of the ISM of NGC 891 by Hughes et al (2014) to a larger sample of galaxies. New Herschel observations of the HEROES galaxies and a qualitative and quantitative analysis of them are presented in Paper I of the project (Verstappen et al 2013).…”

Section: Introductionmentioning

confidence: 99%

HERschelObservations of Edge-on Spirals (HEROES)

Allaert

Gentile

Baes

et al. 2015

A&A

Self Cite

View full text Add to dashboard Cite

Context. Edge-on galaxies can offer important insight into galaxy evolution because they are the only systems where the distribution of the different components can be studied both radially and vertically. The HEROES project was designed to investigate the interplay between the gas, dust, stars, and dark matter (DM) in a sample of 7 massive edge-on spiral galaxies. Aims. In this second HEROES paper, we present an analysis of the atomic gas content of 6 out of 7 galaxies in our sample. The remaining galaxy was recently analysed according to the same strategy. The primary aim of this work is to constrain the surface density distribution, the rotation curve, and the geometry of the gas disks in a homogeneous way. In addition we identify peculiar features and signs of recent interactions. Methods. We have constructed detailed tilted-ring models of the atomic gas disks based on new GMRT 21-cm observations of NGC 973 and UGC 4277 and re-reduced archival H  data of NGC 5907, NGC 5529, IC 2531, and NGC 4217. Potential degeneracies between different models were resolved by requiring good agreement with the data in various representations of the data cubes. Results. From our modelling we find that all but one galaxy are warped along the major axis. In addition, we identify warps along the line of sight in three galaxies. A flaring gas layer is required to reproduce the data for only one galaxy, but (moderate) flares cannot be ruled out for the other galaxies either. A coplanar ring-like structure is detected outside the main disk of NGC 4217, which we suggest could be the remnant of a recent minor merger event. We also find evidence of a radial inflow of 15 ± 5 km s −1 in the disk of NGC 5529, which might be related to the ongoing interaction with two nearby companions. For NGC 5907, the extended, asymmetric, and strongly warped outer regions of the H  disk also suggest a recent interaction. In contrast, the inner disks of these three galaxies (NGC 4217, NGC 5529, and NGC 5907) show regular behaviour and seem largely unaffected by the interactions. Our models further support earlier claims of prominent spiral arms in the disks of IC 2531 and NGC 5529. Finally, we detect a dwarf companion galaxy at a projected distance of 36 kpc from the centre of NGC 973.

show abstract

“…The scale heights have been shown to be comparable for stars and dust in low mass galaxies (Seth et al 2005), but for high mass galaxies the ISM is considered to collapse into dust lanes distributed in thin disks (Dalcanton et al 2004). Also model fitting to several edge-on galaxies have resulted in smaller dust scale heights compared to the vertical extent of the thick disk composed of old stars (Jansen et al 1994;Xilouris et al 1999;Bianchi 2007;De Geyter et al 2013Verstappen et al 2013). The scale height of dust in galaxies is, however, still debated with several galaxies showing evidence of extra-planar dust (e.g., Howk & Savage 1999;Alton et al 2000;Thompson et al 2004).…”

Section: Skirt Model Distribution: 3d Stellar and Dust Geometriesmentioning

confidence: 99%

“…The exponential distribution of the dust has been proven adequate to describe the vertical distribution of dust in a galaxy's disk (e.g., Verstappen et al 2013;Hughes et al 2014). The effect of a twophase dust medium with clumpy dust features is studied and discussed in Sect.…”

Section: Skirt Model Distribution: 3d Stellar and Dust Geometriesmentioning

confidence: 99%

High-resolution, 3D radiative transfer modeling

Looze

Fritz

Baes

et al. 2014

A&A

100

114

View full text Add to dashboard Cite

Context. Dust reprocesses about half of the stellar radiation in galaxies. The thermal re-emission by dust of absorbed energy is considered to be driven merely by young stars so is often applied to tracing the star formation rate in galaxies. Recent studies have argued that the old stellar population might be responsible for a non-negligible fraction of the radiative dust heating. Aims. In this work, we aim to analyze the contribution of young ( < ∼ 100 Myr) and old (∼10 Gyr) stellar populations to radiative dust heating processes in the nearby grand-design spiral galaxy M 51 using radiative transfer modeling. High-resolution 3D radiative transfer (RT) models are required to describe the complex morphologies of asymmetric spiral arms and clumpy star-forming regions and to model the propagation of light through a dusty medium. Methods. In this paper, we present a new technique developed to model the radiative transfer effects in nearby face-on galaxies. We construct a high-resolution 3D radiative transfer model with the Monte-Carlo code SKIRT to account for the absorption, scattering, and non-local thermal equilibrium (NLTE) emission of dust in M 51. The 3D distribution of stars is derived from the 2D morphology observed in the IRAC 3.6 µm, GALEX FUV, Hα, and MIPS 24 µm wavebands, assuming an exponential vertical distribution with an appropriate scale height. The dust geometry is constrained through the far-ultraviolet (FUV) attenuation, which is derived from the observed total-infrared-to-far-ultraviolet luminosity ratio. The stellar luminosity, star formation rate, and dust mass have been scaled to reproduce the observed stellar spectral energy distribution (SED), FUV attenuation, and infrared SED. Results. The dust emission derived from RT calculations is consistent with far-infrared and submillimeter observations of M 51, implying that the absorbed stellar energy is balanced by the thermal re-emission of dust. The young stars provide 63% of the energy for heating the dust responsible for the total infrared emission (8−1000 µm), while 37% of the dust emission is governed through heating by the evolved stellar population. In individual wavebands, the contribution from young stars to the dust heating dominates at all infrared wavebands but gradually decreases towards longer infrared and submillimeter wavebands for which the old stellar population becomes a non-negligible source of heating. Upon extrapolation of the results for M 51, we present prescriptions for estimating the contribution of young stars to the global dust heating based on a tight correlation between the dust heating fraction and specific star formation rate.

show abstract

HERschelObservations of Edge-on Spirals (HEROES)

Cited by 48 publications

References 94 publications

Cold gas properties of theHerschelReference Survey

Cold gas properties of theHerschelReference Survey

HERschelObservations of Edge-on Spirals (HEROES)

High-resolution, 3D radiative transfer modeling

Contact Info

Product

Resources

About