A5022358260- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Calibration and Measurement Techniques
- Marine and coastal ecosystems
- Gamma-ray bursts and supernovae
- Remote Sensing in Agriculture
- Planetary Science and Exploration
- Astronomical Observations and Instrumentation
- Satellite Image Processing and Photogrammetry
- Atmospheric Ozone and Climate
- Astrophysics and Cosmic Phenomena
- Spacecraft and Cryogenic Technologies
- Atmospheric and Environmental Gas Dynamics
- Spacecraft Design and Technology
- Water Quality Monitoring and Analysis
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- Geophysics and Gravity Measurements
- Geochemistry and Geologic Mapping
- Solar and Space Plasma Dynamics
- Adaptive optics and wavefront sensing
- History and Developments in Astronomy
- Urban Heat Island Mitigation
National Physical Laboratory
2021-2024
Cardiff University
2019-2021
Université Paris-Sud
2017-2019
Université Paris-Saclay
2017-2019
Centre National de la Recherche Scientifique
2017-2019
Institut d'Astrophysique Spatiale
2017-2019
University of Canterbury
2015-2017
Ghent University
2016-2017
The purpose of this work is the characterization radial distribution dust, stars, gas, and star-formation rate (SFR) in a sub-sample 18 face-on spiral galaxies extracted from DustPedia sample. This study performed by exploiting multi-wavelength, UV to sub-mm bands, database, addition molecular (12CO) atomic (HI) gas maps metallicity abundance information available literature. We fitted surface brightness profiles tracers dust mass density total SFR with an exponential curve derived their...
Within the framework of DustPedia project we investigate properties cosmic dust and its interaction with stellar radiation (originating from different populations) for 814 galaxies in nearby Universe, all observed by Herschel Space Observatory. We take advantage widely used galaxy SED fitting code CIGALE, properly adapted to include state-of-the-art model THEMIS. Using photometry determine physical galaxies, such as, mass, star-formation rate, bolometric luminosity as well unattenuated...
The LANDHYPERNET and WATERHYPERNET networks (which together make up the HYPERNETS network) consist of a set autonomous hyperspectral spectroradiometers (HYPSTAR ® ) acquiring fiducial reference measurements surface reflectance at various sites covering wide range types (both land water) for use in satellite Earth observation validation remote sensing applications. This paper describes processing algorithm HYPSTAR data products. hypernets_processor is Python software package to process...
We combine samples of nearby galaxies with Herschel photometry selected on their dust, metal, HI, and stellar mass content, compare these to chemical evolution models in order discriminate between different dust sources. In a companion paper, we used HI-selected sample reveal sub-sample very gas rich (gas fraction > 80 per cent) sources masses significantly below predictions from simple models, well $M_d/M_*$ $M_d/M_{gas}$ scaling relations seen stellar-selected local galaxies. use model...
Observations of evolution in the dust-to-metal ratio allow us to constrain dominant dust processing mechanisms. In this work, we present a study and dust-to-gas ratios sub-sample ~500 DustPedia galaxies. Using literature MUSE emission line fluxes, derived gas-phase metallicities (oxygen abundances) for over 10 000 individual regions determine characteristic each galaxy. We how relative dust, gas, metal contents galaxies evolve by using metallicity gas fraction as proxies evolutionary state....
The radiation of stars heats dust grains in the diffuse interstellar medium and star-forming regions galaxies. Modelling this interaction provides information on galaxies, a vital ingredient for their evolution. It is not straightforward to identify stellar populations heating dust, link attenuation emission sub-galactic scale. Radiative transfer models are able simulate dust-starlight realistic, three-dimensional setting. We investigate mechanisms local global galactic scale, using...
Aims . We aim to study the fraction of stellar radiation absorbed by dust, f abs , in 814 galaxies different morphological types. The targets constitute vast majority (93%) DustPedia sample, including almost all large (optical diameter larger than 1′), nearby ( v ≤ 3000 km s −1 ) observed with Herschel Space Observatory. Methods For each object, we modelled spectral energy distribution from ultraviolet sub-millimetre using dedicated, aperture-matched photometry and Code Investigating GALaxy...
A common assumption is that galaxies fall in two distinct regions of a plot specific star formation rate (SSFR) versus galaxy stellar mass: star-forming main sequence (GMS) and separate region ‘passive’ or ‘red dead galaxies’. Starting from volume-limited sample nearby designed to contain most the mass this volume, thus representing end-point ≃12 billion years evolution, we investigate distribution diagram today. We show follow strongly curved extended GMS with steep negative slope at high...
The purpose of this work is the characterization main scaling relations between all ISM components (dust, atomic/molecular/total gas), gas-phase metallicity, and other galaxy properties, such as Mstar morphology, for late-type galaxies in Local Universe. This study performed by extracting from entire DustPedia sample exploiting large homogeneous dataset available thanks to project. consists 436 with morphological stage T = 1 10, 6 x 10^7 3 10^11 Msun, SFR 10^(-4) 60 Msun/yr, 12 + log(O/H) 8...
Satellites are now routinely used for measuring water and land surface reflectance hence environmentally relevant parameters such as aquatic chlorophyll a concentration terrestrial vegetation indices. For each satellite mission, radiometric validation is needed at bottom of atmosphere all spectral bands covering typical conditions where the data will be used. Existing networks AERONET-OC RadCalNet provide vital information validation, but (AERONET-OC) do not cover or (RadCalNet) types...
We present the properties of first 250 μm blind sample nearby galaxies (15 < D 46 Mpc) containing 42 objects from Herschel Astrophysical Terahertz Large Area Survey. Herschel's sensitivity probes faint end dust luminosity function for time, spanning a range stellar mass (7.4 M⋆ 11.3 log10 M⊙), star formation activity (−11.8 SSFR −8.9 yr−1), gas fraction (3–96 per cent), and colour (0.6 FUV–KS 7.0 mag). The median cold temperature is 14.6 K, colder than in Reference Survey (18.5 K) Planck...
We present a study of the dust, stars and atomic gas (HI) in an HI-selected sample local galaxies (z<0.035) Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) fields. This reveals population very high fraction (>80 per cent), low stellar mass sources that appear to be earliest stages their evolution. compare this with dust selected samples scaling relations over wide range (proxy for evolutionary state galaxy). The most robust are those linked NUV-r (SSFR) fraction, these do not...
Aims. The DustPedia project is capitalising on the legacy of Herschel Space Observatory, using cutting-edge modelling techniques to study dust in 875 galaxies – representing vast majority extended within 3000 km s -1 that were observed by . This work requires a database multiwavelength imagery and photometry greatly exceeds scope (in terms wavelength coverage number galaxies) any previous local-Universe survey. Methods. We constructed containing our own custom reductions, along with...
ABSTRACT The dust mass absorption coefficient, κd is the conversion function used to infer physical masses from observations of emission. However, it notoriously poorly constrained, and highly uncertain how varies, either between or within galaxies. Here we present results a proof-of-concept study, using DustPedia data for two nearby face-on spiral galaxies M 74 (NGC 628) 83 5236), create first ever maps in We determine an empirical method that exploits fact dust-to-metals ratio interstellar...
This paper describes a prototype network of automated in situ measurements hyperspectral water reflectance suitable for satellite validation and quality monitoring. Radiometric satellite-derived is essential to ensure that only reliable data, e.g., estimating parameters such as chlorophyll concentration, reach end-users. Analysis the differences between measurements, particularly unmasked outliers, can provide recommendations on where data processing algorithms need be improved. In massively...
We present the dust mass function (DMF) of 15,750 galaxies with redshift $z< 0.1$, drawn from overlapping area GAMA and {\it H-}ATLAS surveys. The DMF is derived using density corrected $V_{\rm max}$ method, where we estimate using: (i) normal photometric selection limit ($pV_{\rm max}$) (ii) a bivariate brightness distribution (BBD) technique, which accounts for two effects. fit data Schechter function, find $M^{*}=(4.65\pm0.18)\times 10^{7}\,h^2_{70}\, M_{\odot}$, $\alpha=(1.22\pm 0.01)$,...
Scaling laws of dust, HI gas and metal mass with stellar mass, specific star formation rate metallicity are crucial to our understanding the buildup galaxies through their enrichment metals dust. In this work, we analyse how dust content varies ($M_{\text{HI}}$/$M_{\star}$) across a diverse sample 423 nearby galaxies. The observed trends interpreted set Dust Element evolUtion modelS (DEUS) - incluidng production, grain growth, destruction within Bayesian framework enable rigorous search...
We compare the spectral energy distributions (SEDs) and inferred physical properties for simulated observed galaxies at low redshift. exploit UV-submillimetre mock fluxes of ~7000 z=0 from EAGLE suite cosmological simulations, derived using radiative transfer code SKIRT. these to ~800 in range, DustPedia sample nearby galaxies. To derive global properties, we apply SED fitting CIGALE consistently both data sets, same set ~80 million models. The results this comparison reveal overall...
The galaxies found in optical surveys fall two distinct regions of a diagram colour versus absolute magnitude: the red sequence and blue cloud with green valley between. We show that submillimetre survey have almost opposite distribution this diagram, forming `green mountain'. these distinctive distributions follow naturally from single, continuous, curved Galaxy Sequence specific star-formation rate stellar mass without there being need for separate star-forming galaxy Main region passive...
This paper demonstrates the use of a novel, autonomous hyperspectral surface reflectance data collected at Wytham Woods, United Kingdom (WWUK) as part LANDHYPERNET network for validation multispectral from Sentinel-2, Landsat 8 and 9. The deployment HYPSTAR instrument site corresponding quality control products is described. In addition, methodology based upon metrological principles outlined showing propagation uncertainties satellite to enable conformity testing using mission requirements....
Context . Dust in late-type galaxies the local Universe is responsible for absorbing approximately one third of energy emitted by stars. It often assumed that dust heating mainly attributable to absorption ultraviolet and optical photons youngest (≤100 Myr) Consequently, thermal re-emission at far-infrared wavelengths linked star-formation activity a galaxy. However, several studies argue contribution much older stellar populations might be more significant than previously thought. Advances...
Interstellar dust absorbs stellar light very efficiently and thus shapes the energetic output of galaxies. Studying impact different populations on heating remains hard because it requires decoupling relative geometry stars dust, involves complex processes as scattering non-local heating. We aim to constrain distribution in spiral galaxy M81 create a realistic model radiation field that describes observations. Investigating dust-starlight interaction local scales, we want quantify...
Aims. We compare the far-infrared to sub-millimetre dust emission properties measured in high Galactic latitude cirrus with those determined a sample of 204 late-type DustPedia galaxies. The aim is verify if it appropriate use Milky Way derive masses external Methods. used Herschel observations and atomic molecular gas estimate ϵ (250 μ m), disc-averaged emissivity at 250 m, from this, absorption cross section per H atom σ m) mass κ m). requires one assumption, which CO-to-H 2 conversion...
We use a sub-set of the DustPedia galaxy sample (461 galaxies) to investigate effect environment has had on galaxies. consider Virgo cluster and field samples also assign density contrast parameter each galaxy, as defined by local SDSS their chemical evolution (using M_{Dust}/M_{Baryon} M_{Gas}/M_{Baryon}), specific star formation rate (SFR/M_{Stars}), efficiency (SFR/M_{Gas}), stars-to-dust mass ratio (M_{Stars}/M_{Dust}), gas-to-dust (M_{Gas}/M_{Dust}) relationship between per unit dust...