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Can planet formation resolve the dust budget crisis in high redshift galaxies?
Authors:
D. H. Forgan,
K. Rowlands,
H. L. Gomez,
E. L. Gomez,
S. P. Schofield,
L. Dunne,
S. Maddox
Abstract:
The process of planet formation offers a rich source of dust production via grain growth in protostellar discs, and via grinding of larger bodies in debris disc systems. Chemical evolution models, designed to follow the build up of metals and dust in galaxies, do not currently account for planet formation. We consider the possibility that the apparent under-prediction of dust mass in high redshift…
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The process of planet formation offers a rich source of dust production via grain growth in protostellar discs, and via grinding of larger bodies in debris disc systems. Chemical evolution models, designed to follow the build up of metals and dust in galaxies, do not currently account for planet formation. We consider the possibility that the apparent under-prediction of dust mass in high redshift galaxies by chemical evolution models could be in part, due to these models neglecting this process, specifically due to their assumption that a large fraction of the dust mass is removed from the interstellar medium during star formation (so-called astration). By adding a planet formation phase into galaxy chemical evolution, we demonstrate that the dust budget crisis can be partially ameliorated by a factor of 1.3-1.5 only if a) circumstellar discs prevent a large fraction of the dust mass entering the star during its birth, and b) that dust mass is preferentially liberated via jets, winds and outflows rather than accreted into planetary-mass bodies.
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Submitted 23 August, 2017;
originally announced August 2017.
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Using dust, gas and stellar mass selected samples to probe dust sources and sinks in low metallicity galaxies
Authors:
P. De Vis,
H. L. Gomez,
S. P. Schofield,
S. Maddox,
L. Dunne,
M. Baes,
P. Cigan,
C. J. R. Clark,
E. L. Gomez,
M. Lara-López,
M. Owers
Abstract:
We combine samples of nearby galaxies with Herschel photometry selected on their dust, metal, HI, and stellar mass content, and compare these to chemical evolution models in order to discriminate between different dust sources. In a companion paper, we used a HI-selected sample of nearby galaxies to reveal a sub-sample of very gas rich (gas fraction > 80 per cent) sources with dust masses signific…
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We combine samples of nearby galaxies with Herschel photometry selected on their dust, metal, HI, and stellar mass content, and compare these to chemical evolution models in order to discriminate between different dust sources. In a companion paper, we used a HI-selected sample of nearby galaxies to reveal a sub-sample of very gas rich (gas fraction > 80 per cent) sources with dust masses significantly below predictions from simple chemical evolution models, and well below $M_d/M_*$ and $M_d/M_{gas}$ scaling relations seen in dust and stellar-selected samples of local galaxies. We use a chemical evolution model to explain these dust-poor, but gas-rich, sources as well as the observed star formation rates (SFRs) and dust-to-gas ratios. We find that (i) a delayed star formation history is required to model the observed SFRs; (ii) inflows and outflows are required to model the observed metallicities at low gas fractions; (iii) a reduced contribution of dust from supernovae (SNe) is needed to explain the dust-poor sources with high gas fractions. These dust-poor, low stellar mass galaxies require a typical core-collapse SN to produce 0.01 - 0.16 $M_{\odot}$ of dust. To match the observed dust masses at lower gas fractions, significant grain growth is required to counteract the reduced contribution from dust in SNe and dust destruction from SN shocks. These findings are statistically robust, though due to intrinsic scatter it is not always possible to find one single model that successfully describes all the data. We also show that the dust-to-metals ratio decreases towards lower metallicity.
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Submitted 5 May, 2017;
originally announced May 2017.
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Herschel-ATLAS: Revealing dust build-up and decline across gas, dust and stellar mass selected samples: I. Scaling relations
Authors:
P. De Vis,
L. Dunne,
S. Maddox,
H. L. Gomez,
C. J. R. Clark,
A. E. Bauer,
S. Viaene,
S. P. Schofield,
M. Baes,
A. J. Baker,
N. Bourne,
S. P. Driver,
S. Dye,
S. A. Eales,
C. Furlanetto,
R. J. Ivison,
A. S. G. Robotham,
K. Rowlands,
D. J. B. Smith,
M. W. L. Smith,
E. Valiante,
A. H. Wright
Abstract:
We present a study of the dust, stars and atomic gas (HI) in an HI-selected sample of local galaxies (z<0.035) in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) fields. This HI-selected sample reveals a population of very high gas fraction (>80 per cent), low stellar mass sources that appear to be in the earliest stages of their evolution. We compare this sample with dust and ste…
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We present a study of the dust, stars and atomic gas (HI) in an HI-selected sample of local galaxies (z<0.035) in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) fields. This HI-selected sample reveals a population of very high gas fraction (>80 per cent), low stellar mass sources that appear to be in the earliest stages of their evolution. We compare this sample with dust and stellar mass selected samples to study the dust and gas scaling relations over a wide range of gas fraction (proxy for evolutionary state of a galaxy). The most robust scaling relations for gas and dust are those linked to NUV-r (SSFR) and gas fraction, these do not depend on sample selection or environment. At the highest gas fractions, our additional sample shows the dust content is well below expectations from extrapolating scaling relations for more evolved sources, and dust is not a good tracer of the gas content. The specific dust mass for local galaxies peaks at a gas fraction of ~75 per cent. The atomic gas depletion time is also longer for high gas fraction galaxies, opposite to the trend found for molecular gas depletion timescale. We link this trend to the changing efficiency of conversion of HI to H2 as galaxies increase in stellar mass surface density as they evolve. Finally, we show that galaxies start out barely obscured and increase in obscuration as they evolve, yet there is no clear and simple link between obscuration and global galaxy properties.
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Submitted 25 October, 2019; v1 submitted 4 October, 2016;
originally announced October 2016.
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An Empirical Determination of the Dust Mass Absorption Coefficient, $κ_{d}$, Using the Herschel Reference Survey
Authors:
Christopher J. R. Clark,
Simon P. Schofield,
Haley L. Gomez,
Jonathan I. Davies
Abstract:
We use the published photometry and spectroscopy of 22 galaxies in the Herschel Reference Survey to determine that the value of the dust mass absorption coefficient $κ_{d}$ at a wavelength of 500 $μm$ is $κ_{500} = 0.051^{+0.070}_{-0.026}\,{\rm m^{2}\,kg^{-1}}$. We do so by taking advantage of the fact that the dust-to-metals ratio in the interstellar medium of galaxies appears to be constant. We…
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We use the published photometry and spectroscopy of 22 galaxies in the Herschel Reference Survey to determine that the value of the dust mass absorption coefficient $κ_{d}$ at a wavelength of 500 $μm$ is $κ_{500} = 0.051^{+0.070}_{-0.026}\,{\rm m^{2}\,kg^{-1}}$. We do so by taking advantage of the fact that the dust-to-metals ratio in the interstellar medium of galaxies appears to be constant. We argue that our value for $κ_{d}$ supersedes that of James et al. (2002) -- who pioneered this approach for determining $κ_{d}$ -- because we take advantage of superior data, and account for a number of significant systematic effects that they did not consider. We comprehensively incorporate all methodological and observational contributions to establish the uncertainty on our value, which represents a marked improvement on the oft-quoted 'order-of-magnitude' uncertainty on $κ_{d}$. We find no evidence that the value of $κ_{d}$ differs significantly between galaxies, or that it correlates with any other measured or derived galaxy properties. We note, however, that the availability of data limits our sample to relatively massive ($10^{9.7}<{M_{\star}}<10^{11.0}\ {\rm M_{\odot}}$), high metallicity ($8.61<[12+{\rm log}_{10}\frac{O}{H}]<8.86$) galaxies; future work will allow us to investigate a wider range of systems.
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Submitted 15 March, 2016;
originally announced March 2016.
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Herschel-ATLAS: The Surprising Diversity of Dust-Selected Galaxies in the Local Submillimetre Universe
Authors:
Christopher J. R. Clark,
Loretta Dunne,
Haley L. Gomez,
Steven Maddox,
Pieter De Vis,
Matthew W. L. Smith,
Steven A. Eales,
Maarten Baes,
George J. Bendo,
Nathan Bourne,
Simon P. Driver,
Simon Dye,
Cristina Furlanetto,
Meiert W. Grootes,
Rob J. Ivison,
Simon P. Schofield,
Aaron S. G. Robotham,
Kate Rowlands,
Catherine Vlahakis,
Paul van der Werf,
Angus Wright,
Gianfranco de Zotti
Abstract:
We present the properties of the first 250 $μ$m blind sample of nearby galaxies (15 < D < 46 Mpc) containing 42 objects from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). Herschel's sensitivity probes the faint end of the dust luminosity function for the first time, spanning a range of stellar mass (7.4 < log$_{10}$ M$_{\star}$ < 11.3 M$_{\odot}$), star formation activity (-11.…
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We present the properties of the first 250 $μ$m blind sample of nearby galaxies (15 < D < 46 Mpc) containing 42 objects from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). Herschel's sensitivity probes the faint end of the dust luminosity function for the first time, spanning a range of stellar mass (7.4 < log$_{10}$ M$_{\star}$ < 11.3 M$_{\odot}$), star formation activity (-11.8 < log$_{10}$ SSFR < -8.9 yr$^{-1}$), gas fraction (3-96 per cent), and colour (0.6 < FUV-Ks < 7.0 mag). The median cold dust temperature is 14.6 K, colder than in the Herschel Reference Survey (18.5 K) and Planck Early Release Compact Source Catalogue 17.7 K. The mean dust-to-stellar mass ratio in our sample is higher than these surveys by factors of 3.7 and 1.8, with a dust mass volume density of (3.7 $\pm$ 0.7) x 10$^{5}$ M$_{\odot}$ Mpc$^{-3}$. Counter-intuitively, we find that the more dust rich a galaxy, the lower its UV attenuation. Over half of our dust-selected sample are very blue in FUV-Ks colour, with irregular and/or highly flocculent morphology, these galaxies account for only 6 per cent of the sample's stellar mass but contain over 35 per cent of the dust mass. They are the most actively star forming galaxies in the sample, with the highest gas fractions and lowest UV attenuation. They also appear to be in an early stage of converting their gas into stars, providing valuable insights into the chemical evolution of young galaxies.
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Submitted 9 June, 2015; v1 submitted 12 February, 2015;
originally announced February 2015.