Results for "F. Galliano"

total 80396took 0.15s
ISM properties in low-metallicity environments I. mid-infrared spectra of dwarf galaxiesOct 04 2005We present new ISOCAM mid-infrared spectra of three starbursting nearby dwarf galaxies, NGC1569, IIZw40, NGC1140 and the 30Dor region of the LMC and explore the properties of the ISM in low-metallicity environments, also using additional sources from ... More
Variations of the Mid-IR Aromatic Features Inside and Among GalaxiesJan 31 2008Feb 01 2008We present the results of a systematic study of mid-IR spectra of Galactic regions, Magellanic HII regions, and galaxies of various types (dwarf, spiral, starburst), observed by the satellites ISO and Spitzer. We study the relative variations of the 6.2, ... More
ISM Properties in Low-Metallicity Environments II. The Dust Spectral Energy Distribution of NGC 1569Jun 10 2003We present new 450 and 850 microns SCUBA data of the dwarf galaxy NGC 1569. We construct the mid-infrared to millimeter SED of NGC 1569, using ISOCAM, ISOPHOT, IRAS, KAO, SCUBA and MAMBO data, and model the SED in order to explore the nature of the dust ... More
The Nature of the Low-Metallicity ISM in the Dwarf Galaxy NGC 1569Dec 19 2002We are modeling the spectra of dwarf galaxies from infrared to submillimeter wavelengths to understand the nature of the various dust components in low-metallicity environments, which may be comparable to the ISM of galaxies in their early evolutionary ... More
Stellar Evolutionary Effects on the Abundances of PAH and SN-Condensed Dust in GalaxiesAug 06 2007Nov 01 2007Spectral and photometric observations of nearby galaxies show a correlation between the strength of their mid-IR aromatic features, attributed to PAH molecules, and their metal abundance, leading to a deficiency of these features in low-metallicity galaxies. ... More
The Interstellar dust properties of nearby galaxiesNov 20 2017Dec 06 2017This article gives an overview of the constitution, physical conditions and observables of dust in the interstellar medium of nearby galaxies. We first review the macroscopic, spatial distribution of dust in these objects, and its consequence on our ability ... More
The Evolution of Dust in the Early Universe with Applications to the Galaxy SDSS J1148+5251May 25 2007Dusty hyperluminous galaxies in the early universe provide unique environments for studying the role of massive stars in the formation and destruction of dust. At redshifts above ~ 6, when the universe was less than ~ 1 Gyr old, dust could have only condensed ... More
The Cycle of Dust in the Milky Way: Clues from the High-Redshift and Local UniverseFeb 27 2009Models for the evolution of dust are used to show that the observed trend of the abundance of polycyclic aromatic hydrocarbons (PAHs) with metallicity is the result of the delayed injection of carbon dust that formed in low mass asymptotic giant branch ... More
MIPS 24-160 micron photometry for the Herschel-SPIRE Local Galaxies Guaranteed Time ProgramsFeb 21 2012We provide an overview of ancillary 24, 70, and 160 micron data from the Multiband Imaging Photometer for Spitzer (MIPS) that are intended to complement the 70-500 micron Herschel Space Observatory photometry data for nearby galaxies obtained by the Herschel-SPIRE ... More
A Multi-Wavelength Infrared Study of NGC 891Jan 27 2009We present a multi-wavlength infrared study of the nearby, edge-on, spiral galaxy NGC 891. We have examined 20 independent, spatially resolved IR images of this galaxy, 14 of which are newly reduced and/or previously unpublished images. These images span ... More
On a class of integrable systems with a quartic first integralApr 22 2013We generalize, to some extent, the results on integrable geodesic flows on two dimensional manifolds with a quartic first integral in the framework laid down by Selivanova and Hadeler. The local structure is first determined by a direct integration of ... More
Associated Stieltjes-Carlitz polynomials and a generalization of Heun's differential equation.Jul 08 1993The generating function of Stieltjes-Carlitz polynomials is a solution of Heun's differential equation and using this relation Carlitz was the first to get exact closed forms for some Heun functions. Similarly the associated Stieltjes-Carlitz polynomials ... More
From asymptotics to spectral measures: determinate versus indeterminate moment problemsDec 02 2005In the field of orthogonal polynomials theory, the classical Markov theorem shows that for determinate moment problems the spectral measure is under control of the polynomials asymptotics. The situation is completely different for indeterminate moment ... More
The thermal dust emission in the N158-N159-N160 (LMC) star forming complex mapped by Spitzer, Herschel and LABOCAFeb 12 2013We present a study of the infrared/submm emission of the LMC star forming complex N158-N159-N160. Combining observations from the Spitzer Space Telescope (3.6-70um), the Herschel Space Observatory (100-500um) and LABOCA (870um) allows us to work at the ... More
Further results on non-diagonal Bianchi type III vacuum metricsFeb 22 2011We present the derivation, for these vacuum metrics, of the Painlev\'e VI equation first obtained by Christodoulakis and Terzis, from the field equations for both minkowskian and euclidean signatures. This allows a complete discussion and the precise ... More
Explicit integrable systems on two dimensional manifolds with a cubic first integralFeb 10 2010A few years ago Selivanova gave an existence proof for some integrable models, in fact geodesic flows on two dimensional manifolds, with a cubic first integral. However the explicit form of these models hinged on the solution of a nonlinear third order ... More
Integrability versus separability for the multi-centre metricsSep 22 2003The multi-centre metrics are a family of euclidean solutions of the empty space Einstein equations with self-dual curvature. For this full class, we determine which metrics do exhibit an extra conserved quantity quadratic in the momenta, induced by a ... More
Determining dust temperatures and masses in the Herschel era: the importance of observations longward of 200 micronMay 14 2010The properties of the dust grains (e.g., temperature and mass) can be derived from fitting far-IR SEDs (>100 micron). Only with SPIRE on Herschel has it been possible to get high spatial resolution at 200 to 500 micron that is beyond the peak (~160 micron) ... More
The Herschel revolution: unveiling the morphology of the high mass star formation sites N44 and N63 in the LMCMay 11 2010We study the structure of the medium surrounding sites of high-mass star formation to determine the interrelation between the HII regions and the environment from which they were formed. The density distribution of the surroundings is key in determining ... More
Heun functions versus elliptic functionsDec 02 2005We present some recent progresses on Heun functions, gathering results from classical analysis up to elliptic functions. We describe Picard's generalization of Floquet's theory for differential equations with doubly periodic coefficients and give the ... More
Zoll and Tannery metrics from a superintegrable geodesic flowApr 07 2014We prove that for Matveev and Shevchishin superintegrable system, with a linear and a cubic integral, the metrics defined on S^2 and on Tannery's orbifold T^2 are either Zoll or Tannery metrics.
Reply to Professor Yehia comments arXiv:1305.0026May 05 2013This is a reply to Professor Yehia Comments in arXiv:1305.0026
Bianchi type II,III and V diagonal Einstein metrics re-visitedFeb 07 2010We present, for both minkowskian and euclidean signatures, short derivations of the diagonal Einstein metrics for Bianchi type II, III and V. For the first two cases we show the integrability of the geodesic flow while for the third case a somewhat unusual ... More
Global structure and geodesics for Koenigs superintegrable systemsOct 28 2015Starting from the framework defined by Matveev and Shevchishin we derive the local and the global structure for the four types of super-integrable Koenigs metrics. These dynamical systems are always defined on non-compact manifolds, namely $\,{\mb R}^2\,$ ... More
Bianchi III and V Einstein metricsJun 18 2008We present diagonal Einstein metrics for Bianchi III and V, both for minkowskian and euclidean signatures and we show that the Einstein Bianchi III metrics have an integrable geodesic flow.
A systematic metallicity study of DustPedia galaxies reveals evolution in the dust-to-metal ratiosJan 25 2019Observations of evolution in the dust-to-metal ratio allow us to constrain the dominant dust processing mechanisms. In this work, we present a study of the dust-to-metal and dust-to-gas ratios in a sub-sample of ~500 DustPedia galaxies. Using literature ... More
Probing the baryon cycle of galaxies with SPICA mid- and far-infrared observationsNov 30 2017The SPICA mid and far-infrared telescope will address fundamental issues in our understanding of star formation and ISM physics in galaxies. A particular hallmark of SPICA is the outstanding sensitivity enabled by the cold telescope, optimized detectors, ... More
The fraction of bolometric luminosity absorbed by dust in DustPedia galaxiesOct 02 2018We study the fraction of stellar radiation absorbed by dust, f_abs, in 814 galaxies of different morphological types. The targets constitute the vast majority (93%) of the DustPedia sample, including almost all large (optical diameter larger than 1'), ... More
The relationship between polycyclic aromatic hydrocarbon emission and far-infrared dust emission from NGC 2403 and M83Dec 23 2014We examine the relation between polycyclic aromatic hydrocarbon (PAH) emission at 8 microns and far-infrared emission from hot dust grains at 24 microns and from large dust grains at 160 and 250 microns in the nearby spiral galaxies NGC 2403 and M83 using ... More
Radial distribution of dust, stars, gas, and star-formation rate in DustPedia face-on galaxiesJun 16 2017The purpose of this work is the characterization of the radial distribution of dust, stars, gas, and star-formation rate (SFR) in a sub-sample of 18 face-on spiral galaxies extracted from the DustPedia sample. This study is performed by exploiting the ... More
Mid infrared properties of distant infrared luminous galaxiesJan 20 2006We present evidence that the mid infrared (MIR) is a good tracer of the total infrared luminosity, L(IR), and star formation rate (SFR), of galaxies up to z 1.3. We use deep MIR images from the Infrared Space Observatory (ISO) and the Spitzer Space Telescope ... More
Star Formation in Collision Debris: Insights from the modeling of their Spectral Energy DistributionOct 11 2010During galaxy-galaxy interactions, massive gas clouds can be injected into the intergalactic medium which in turn become gravitationally bound, collapse and form stars, star clusters or even dwarf galaxies. The objects resulting from this process are ... More
Dust emission profiles of DustPedia galaxiesNov 21 2018Most radiative transfer models assume that dust in spiral galaxies is distributed exponentially. In this paper our goal is to verify this assumption by analysing the two-dimensional large-scale distribution of dust in galaxies from the DustPedia sample. ... More
Dust emission in early-type galaxies: The mid-infrared viewDec 01 2003We present mid-infrared (MIR) maps for a sample of 18 early-type galaxies observed at 4.5, 6.7 and 15 microns with the ISOCAM instrument on board the ISO satellite with a 6'' spatial resolution. We model the Spectral Energy Distribution (SED) of these ... More
ISM Properties in Low-Metallicity Environments III. The Dust Spectral Energy Distributions of II Zw 40, He 2-10 and NGC 1140Jan 28 2005We present new 450 and 850 micron SCUBA data and 1.3 mm MAMBO data of the dwarf galaxies II Zw 40, He 2-10 and NGC 1140. Additional ISOCAM, IRAS as well as ground based data are used to construct the observed mid-infrared to millimeter spectral energy ... More
Old and young stellar populations in DustPedia galaxies and their role in dust heatingMar 14 2019Within the framework of the DustPedia project we investigate the properties of cosmic dust and its interaction with the stellar radiation (originating from different stellar populations) for 814 galaxies in the nearby Universe, all observed by the Herschel ... More
Near-IR 2D-Spectroscopy of the 4''x 4'' region around the Active Galactic Nucleus of NGC1068 with ISAAC/VLTJun 29 2002We present new near-IR long slit spectroscopic data obtained with ISAAC on VLT/ANTU (ESO/Paranal) of the central 4''x 4'' region surrounding the central engine of NGC1068 . Bracket Gamma (Bg) and H2 emission line maps and line profile grids are produced, ... More
Quaternionic metrics from harmonic superspace : lagrangian approach and quotient constructionJan 25 2000Starting from the most general harmonic superspace action of self-interacting Q^+ hypermultiplets in the background of N=2 conformal supergravity, we derive the general action for the bosonic sigma model with a generic 4n dimensional quaternionic-Kahler ... More
Nuclear embedded star clusters in NGC 7582Mar 23 2006We report on the discovery of several compact regions of mid-infrared emission in the starforming circum nuclear disk of the starburst/Seyfert2 galaxy NGC7582. The compact sources do not have counterparts in the optical and near-infrared, suggesting that ... More
Quaternionic Taub-NUT from the harmonic space approachSep 15 1998We use the harmonic space technique to construct explicitly a quaternionic extension of the Taub-NUT metric. It depends on two parameters, the first being the Taub-NUT `mass' and the second one the cosmological constant.
Influence of the Environment on PAH Emission in Star-Forming RegionsDec 08 2010We investigate the emission properties of polycyclic aromatic hydrocarbons (PAHs) in various metallicity environments with the Infrared Spectrograph on board Spitzer. Local giant HII regions are used as references as they enable access to the distinct ... More
Harmonic Space Construction of the Quaternionic Taub-NUT metricOct 01 1998Oct 07 1998We present details of the harmonic space construction of a quaternionic extension of the four-dimensional Taub-NUT metric. As the main merit of the harmonic space approach, the metric is obtained in an explicit form following a generic set of rules. It ... More
Quantum integrability of quadratic Killing tensorsDec 16 2004Mar 17 2005Quantum integrability of classical integrable systems given by quadratic Killing tensors on curved configuration spaces is investigated. It is proven that, using a "minimal" quantization scheme, quantum integrability is insured for a large class of classic ... More
Embedded clusters in NGC1808 central starburst - Near-infrared imaging and spectroscopyMay 28 2008In the course of a mid-infrared imaging campaign of close-by active galaxies, we discovered the mid-infrared counterparts of bright compact radio sources in the central star-forming region of NGC1808. We aim at confirming that these sources are deeply ... More
A new integrable system on the sphere and conformally equivariant quantizationJul 16 2010May 31 2011Taking full advantage of two independent projectively equivalent metrics on the ellipsoid leading to Liouville integrability of the geodesic flow via the well-known Jacobi-Moser system, we disclose a novel integrable system on the sphere $S^n$, namely ... More
Modeling ionized gas in low-metallicity environments: the Local Group dwarf galaxy IC10Oct 08 2018Our objective is to investigate the physical properties of the ionised gas of the low-metallicity dwarf galaxy, IC 10, at various spatial scales: from individual HII regions to the entire galaxy scale and examine whether diagnostics for integrated measurements ... More
Extremely massive young clusters in NGC1365Jul 21 2008In a previous work, three bright MIR/radio sources were discovered in the nuclear region of NGC1365. We here confirm that these sources are young and massive ``embedded'' clusters, and derive their parameters, such as extinction, age and mass. Using ISAAC ... More
Neutral gas heating by X-rays in primitive galaxies: Infrared observations of IZw18 with HerschelFeb 23 2017Mar 03 2017(abridged) The dominant thermal mechanisms in the neutral interstellar medium, which acts as a star-forming gas reservoir, are uncertain in extremely metal-poor galaxies. Our objective is to identify the heating mechanisms in one such galaxy, IZw18, and ... More
Integrable geodesic flows and Multi-Centre versus Bianchi A metricsMay 29 2006It is shown that most, but not all, of the four dimensional metrics in the Multi-Centre family with integrable geodesic flow may be recognized as belonging to spatially homogeneous Bianchi type A metrics. We show that any diagonal bi-axial Bianchi II ... More
Neumann-like integrable modelsDec 09 2005Jul 19 2006A countable class of integrable dynamical systems, with four dimensional phase space and conserved quantities in involution (H\_n,I\_n) are exhibited. For $n=1$ we recover Neumann sytem on T*S^2. All these systems are also integrable at the quantum level. ... More
Physical conditions in the gas phases of the giant HII region LMC-N11 unveiled by Herschel - I. Diffuse [CII] and [OIII] emission in LMC-N11BSep 26 2012Nov 14 2012(Abridged) The Magellanic Clouds provide a nearby laboratory for metal-poor dwarf galaxies. The low dust abundance enhances the penetration of UV photons into the interstellar medium (ISM), resulting in a relatively larger filling factor of the ionized ... More
Quaternionic Extension of the Double Taub-NUT MetricApr 09 2001May 10 2001Starting from the generic harmonic superspace action of the quaternion-K\"ahler sigma models and using the quotient approach we present, in an explicit form, a quaternion-K\"ahler extension of the double Taub-NUT metric. It possesses $U(1)\times U(1)$ ... More
Self-adjoint extensions of operators and the teaching of quantum mechanicsMar 28 2001For the example of the infinitely deep well potential, we point out some paradoxes which are solved by a careful analysis of what is a truly self-adjoint operator. We then describe the self-adjoint extensions and their spectra for the momentum and the ... More
Massive Clusters in the Inner Regions of NGC 1365: Cluster Formation and Gas Dynamics in Galactic BarsJul 15 2009Jul 21 2009Cluster formation and gas dynamics in the central regions of barred galaxies are not well understood. This paper reviews the environment of three 10^7 Msun clusters near the inner Lindblad resonance of the barred spiral NGC 1365. The morphology, mass, ... More
Bianchi I meets the Hubble diagramMay 26 2014Sep 15 2014We improve existing fits of the Bianchi I metric to the Hubble diagram of supernovae and find an intriguing yet non-significant signal for anisotropy that should be verified or falsified in the near future by the Large Synoptic Survey Telescope. Since ... More
The molecular gas reservoir of 6 low-metallicity galaxies from the Herschel Dwarf Galaxy Survey: A ground-based follow-up survey of CO(1-0), CO(2-1), and CO(3-2)Jan 02 2014We aim to quantify the molecular gas reservoir in a subset of 6 low-metallicity galaxies from the Herschel Dwarf Galaxy Survey with newly acquired CO data, and link this reservoir to the observed star formation activity. We present CO(1-0), CO(2-1), and ... More
A milestone toward understanding PDR properties in the extreme environment of LMC-30DorMar 11 2016More complete knowledge of galaxy evolution requires understanding the process of star formation and interaction between the interstellar radiation field and the interstellar medium in galactic environments traversing a wide range of physical parameter ... More
The SAGE-Spec Spitzer Legacy program: The life-cycle of dust and gas in the Large Magellanic Cloud. Point source classification ISep 29 2010We present the classification of 197 point sources observed with the Infrared Spectrograph in the SAGE-Spec Legacy program on the Spitzer Space Telescope. We introduce a decision-tree method of object classification based on infrared spectral features, ... More
Explicit metrics for a class of two-dimensional superintegrable systemsMar 03 2014Aug 21 2014We obtain, in local coordinates, the explicit form of the two-dimensional, super-integrable systems of Matveev and Shevchishin involving cubic integrals. This enables us to determine for which values of the parameters these systems are indeed globally ... More
Evolution of the Unidentified Infrared Bands in the Nucleus of the Starburst Galaxy NGC 1097Jan 31 2018We present the analysis of the Unidentified Infrared Bands (UIB) in the starburst galaxy NGC 1097. We have combined spectral maps observed with the AKARI/IRC and Spitzer/IRS instruments, in order to study all of the most prominent UIBs, from 3 to 20 micron. ... More
U(1) x U(1) Quaternionic Metrics from Harmonic SuperspaceOct 30 2001Mar 25 2002We construct, using harmonic superspace and the quaternionic quotient approach, a quaternionic-K\"ahler extension of the most general two centres hyper-K\"ahler metric. It possesses $U(1)\times U(1)$ isometry, contains as special cases the quaternionic-K\"ahler ... More
The origin and evolution of dust in high-redshift galaxiesNov 07 2007Dusty hyperluminous galaxies in the early universe provide unique environments for studying the role of massive stars in the formation and destruction of dust. At redshifts above 6, when the universe was less than 1 Gyr old, dust could have only condensed ... More
The effects of star formation on the low-metallicity ISM: NGC4214 mapped with Herschel/PACS spectroscopyMay 11 2010We present Herschel/PACS spectroscopic maps of the dwarf galaxy NC4214 observed in 6 far infrared fine-structure lines: [C II] 158mu, [O III] 88mu, [O I] 63mu, [O I] 146mu, [N II] 122mu, and [N II] 205mu. The maps are sampled to the full telescope spatial ... More
On the origin of M81 group extended dust emissionOct 22 2010Galactic cirrus emission at far-infrared wavelengths affects many extragalactic observations. Separating this emission from that associated with extragalactic objects is both important and difficult. In this paper we discuss a particular case, the M81 ... More
Mapping the interstellar medium in galaxies with Herschel/SPIREMay 12 2010The standard method of mapping the interstellar medium in a galaxy, by observing the molecular gas in the CO 1-0 line and the atomic gas in the 21-cm line, is largely limited with current telescopes to galaxies in the nearby universe. In this letter, ... More
Non-Standard Grain Properties, Dark Gas Reservoir, and Extended Submillimeter Excess, Probed by Herschel in the Large Magellanic CloudOct 06 2011Aims: In this paper, we perform detailed modelling of the Spitzer and Herschel observations of the LMC, in order to: (i) systematically study the uncertainties and biases affecting dust mass estimates; and to (ii) explore the peculiar ISM properties of ... More
Some cubic birth and death processes and their related orthogonal polynomialsNov 28 2005The orthogonal polynomials with recurrence relation \[(\la\_n+\mu\_n-z) F\_n(z)=\mu\_{n+1} F\_{n+1}(z)+\la\_{n-1} F\_{n-1}(z)\] with two kinds of cubic transition rates $\la\_n$ and $\mu\_n,$ corresponding to indeterminate Stieltjes moment problems, are ... More
Revisiting the location and environment of the central engine in NGC1068Apr 15 2003We revisit in this paper the location of the various components observed in the AGN of NGC1068. Discrepancies between previously published studies are explained, and a new measurement for the absolute location of the K-band emission peak is provided. ... More
High angular resolution near-infrared integral field observations of young star cluster complexes in NGC1365Jul 27 2012This paper presents and examines new near-infrared integral field observations of the three so-called 'embedded star clusters' located in the nuclear region of NGC1365. Adaptive-optics- corrected K-band data cubes were obtained with the ESO/VLT instrument ... More
Astro2020: Unleashing the Potential of Dust Emission as a Window onto Galaxy EvolutionMar 15 2019We present the severe, systematic uncertainties currently facing our understanding of dust emission, which stymie our ability to truly exploit dust as a tool for studying galaxy evolution. We propose a program of study to tackle these uncertainties, describe ... More
Mid-infrared imaging of NGC1068 with VISIR at the VLTJun 03 2005High resolution mid-infrared (MIR) images of the central region of NGC1068 have been obtained with VISIR, the multi-mode MIR instrument recently installed at the ESO/VLT on Paranal. A map of the emission at 12.8mic with increased sensitivity over the ... More
Physical Conditions in the Ionized Gas of 30 DoradusJan 14 2009Jan 25 2009We present a mid-infrared spectroscopic data cube of the central part of 30 Doradus, observed with Spitzer's IRS and MIPS/SED mode. Aromatic dust emission features and emission lines from molecular and atomic hydrogen are detected but not particularly ... More
The Herschel Dwarf Galaxy Survey: I. Properties of the low-metallicity ISM from PACS spectroscopyFeb 10 2015The far-infrared (FIR) lines are key tracers of the physical conditions of the interstellar medium (ISM) and are becoming workhorse diagnostics for galaxies throughout the universe. Our goal is to explain the differences and trends observed in the FIR ... More
The dust properties and physical conditions of the interstellar medium in the LMC massive star forming complex N11Nov 23 2015Nov 25 2015We combine Spitzer and Herschel data of the star-forming region N11 in the Large Magellanic Cloud to produce detailed maps of the dust properties in the complex and study their variations with the ISM conditions. We also compare APEX/LABOCA 870um observations ... More
A multiwavelength study of the Magellanic-type galaxy NGC 4449 - I. Modelling the spectral energy distribution, the ionization structure and the star formation historyFeb 21 2013Apr 25 2013[Abridged] We present an integrated photometric spectral energy distribution (SED) of the Magellanic-type galaxy NGC 4449 from the far-ultraviolet (UV) to the submillimetre, including new observations acquired by the Herschel Space Observatory. We include ... More
Dust Spectral Energy Distributions of Nearby Galaxies: an Insight from the Herschel Reference SurveyFeb 14 2014We gather infrared (IR) photometric data from 8 to 500 microns (Spitzer, WISE, IRAS and Herschel) for all of the HRS galaxies. Draine & Li (2007) models are fit to the data from which the stellar contribution has been carefully removed. We find that our ... More
Herschel and JCMT observations of the early-type dwarf galaxy NGC 205Apr 05 2012We present Herschel dust continuum, James Clerk Maxwell Telescope CO(3-2) observations and a search for [CII] 158 micron and [OI] 63 micron spectral line emission for the brightest early-type dwarf satellite of Andromeda, NGC 205. While direct gas measurements ... More
Revealing the cold dust in low-metallicity environments: I - Photometry analysis of the Dwarf Galaxy Survey with HerschelSep 05 2013We present new photometric data from our Herschel Key Programme, the Dwarf Galaxy Survey (DGS), dedicated to the observation of the gas and dust in 48 low-metallicity environments. They were observed with PACS and SPIRE onboard Herschel at 70,100,160,250,350, ... More
Star-formation rates from young-star counts and the structure of the ISM across the NGC346/N66 complex in the SMCJan 15 2015The rate at which interstellar gas is converted into stars, and its dependence on environment, is one of the pillars on which our understanding of the visible Universe is build. We present a comparison of the surface density of young stars (Sigma_*) and ... More
The nature of the interstellar medium of the starburst low-metallicity galaxy Haro11: a multi-phase model of the infrared emissionSep 04 2012(abridged) Our goal is to describe the multi-phase ISM of the IR bright low-metallicity galaxy Haro 11, dissecting the photoionised and photodissociated gas components. We present observations of the mid- and far-IR fine-structure cooling lines obtained ... More
Gas-to-Dust mass ratios in local galaxies over a 2 dex metallicity rangeDec 12 2013This paper analyses the behaviour of the gas-to-dust mass ratio (G/D) of local Universe galaxies over a large metallicity range. We combine three samples: the Dwarf Galaxy Survey, the KINGFISH survey and a subsample from Galametz et al. (2011) totalling ... More
DustPedia - A Definitive Study of Cosmic Dust in the Local UniverseSep 20 2016The European Space Agency has invested heavily in two cornerstones missions; Herschel and Planck. The legacy data from these missions provides us with an unprecedented opportunity to study cosmic dust in galaxies so that we can answer fundamental questions ... More
Linking dust emission to fundamental properties in galaxies: The low-metallicity pictureJul 20 2015In this work, we aim at providing a consistent analysis of the dust properties from metal-poor to metal-rich environments by linking them to fundamental galactic parameters. We consider two samples of galaxies: the Dwarf Galaxy Survey (DGS) and KINGFISH, ... More
Cold dust clumps in dynamically hot gasMay 18 2010We present clumps of dust emission from Herschel observations of the Large Magellanic Cloud (LMC) and their physical and statistical properties. We catalog cloud features seen in the dust emission from Herschel observations of the LMC, the Magellanic ... More
From forced collapse to H ii region expansion in Mon R2: Envelope density structure and age determination with HerschelOct 30 2015The surroundings of HII regions can have a profound influence on their development, morphology, and evolution. This paper explores the effect of the environment on H II regions in the MonR2 molecular cloud. We aim to investigate the density structure ... More
Probing the Dust Properties of Galaxies at Submillimetre Wavelengths II. Dust-to-gas mass ratio trends with metallicity and the submm excess in dwarf galaxiesApr 05 2011We are studying the effects of submm observations on the total dust mass and thus dust-to-gas mass ratio measurements. We gather a wide sample of galaxies that have been observed at submm wavelengths to model their Spectral Energy Distributions using ... More
Molecular hydrogen emission in the interstellar medium of the Large Magellanic CloudJul 29 2014Nov 03 2014We present the detection and analysis of molecular hydrogen emission toward ten interstellar regions in the Large Magellanic Cloud. We examined low-resolution infrared spectral maps of twelve regions obtained with the Spitzer infrared spectrograph (IRS). ... More
The Spatial Distribution of Dust and Stellar Emission of the Magellanic CloudsOct 29 2012Oct 31 2012We study the emission by dust and stars in the Large and Small Magellanic Clouds, a pair of low-metallicity nearby galaxies, as traced by their spatially resolved spectral energy distributions (SEDs). This project combines Herschel Space Observatory PACS ... More
Mid-Infrared Imaging of Active Galaxies: Active Nuclei and Embedded Star ClustersApr 05 2005High resolution, mid-infrared (MIR) images of a set of nine nearby active galaxies are presented. The data were obtained with the TIMMI2 instrument mounted at the ESO 3.6m telescope using a set of N-band narrow filters. The resulting images have an angular ... More
Probing the interstellar medium of NGC1569 with HerschelAug 28 2014NGC1569 has some of the most vigorous star formation among nearby galaxies. It hosts two super star clusters (SSCs) and has a higher star formation rate (SFR) per unit area than other starburst dwarf galaxies. Extended emission beyond the galaxy's optical ... More
An In-Depth View of the Mid-Infrared Properties of Point Sources and the Diffuse ISM in the SMC Giant HII Region, N66Jun 10 2013(abridged)The focus of this work is to study mid-infrared point sources and the diffuse interstellar medium (ISM) in the low-metallicity (~0.2 solar) giant HII region N66 using the Spitzer Space Telescope's Infrared Spectrograph. We study 14 targeted ... More
Constraining physical conditions for the PDR of Trumpler 14 in the Carina NebulaJan 05 2018We investigate the physical conditions of the CO gas near the young star cluster, Trumpler 14 of the Carina Nebula. The observations presented in this work are taken with the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imaging ... More
Hubble Space Telescope Ultraviolet Spectroscopy of Fourteen Low-Redshift QuasarsOct 13 2006We present low-resolution ultraviolet spectra of 14 low redshift (z<0.8) quasars observed with HST/STIS as part of a Snap project to understand the relationship between quasar outflows and luminosity. By design, all observations cover the CIV emission ... More
The Herschel Exploitation of Local Galaxy Andromeda (HELGA). I: Global far-infrared and sub-mm morphologyDec 14 2011Sep 03 2012We have obtained Herschel images at five wavelengths from 100 to 500 micron of a ~5.5x2.5 degree area centred on the local galaxy M31 (Andromeda), our nearest neighbour spiral galaxy, as part of the Herschel guaranteed time project "HELGA". The main goals ... More
Kinematics of Molecular Gas in the Nucleus of NGC1068, from H2 line emission observed with VLTFeb 23 2001We present results about the distribution and kinematics of the molecular environment of the AGN in NGC1068, over a 1.5'' x 3.5'' region around the central engine in NGC1068, derived from H2 line emission detected with ISAAC at VLT/ANTU on ESO/Paranal. ... More
Elemental depletions in the Magellanic Clouds and the evolution of depletions with metallicityMar 30 2015We present a study of the composition of gas and dust in the Large and Small Magellanic Clouds (LMC and SMC, together -- the MCs) as measured by UV absorption spectroscopy. We have measured P II and Fe II along 85 sightlines toward the MCs using archival ... More
A look at possible microwave dust emission via AKARI infrared all-sky surveysMar 13 2018The anomalous microwave emission (AME) still lacks a conclusive explanation. This excess of emission, roughly between 10 and 50 GHz, correlates spatially with interstellar dust, prompting a "spinning dust" hypothesis: electric dipole emission by rapidly ... More
Probing the Dust Properties of Galaxies up to Submillimetre Wavelengths I. The Spectral Energy Distribution of dwarf galaxies using LABOCASep 30 2009We present 870 micron images of four low metallicity galaxies (NGC1705, Haro11, Mrk1089 and UM311) observed with the Large APEX BOlometer CAmera (LABOCA). We model their spectral energy distributions combining the submm observations of LABOCA, 2MASS, ... More
Constraining physical conditions for the PDR of Trumpler 14 in the Carina NebulaJan 05 2018Feb 27 2018We investigate the physical conditions of the CO gas near the young star cluster, Trumpler 14 of the Carina Nebula. The observations presented in this work are taken with the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imaging ... More
An Overview of the Dwarf Galaxy SurveyMay 12 2013Jun 09 2013The Dwarf Galaxy Survey (DGS) program is studying low-metallicity galaxies using 230h of far-infrared (FIR) and submillimetre (submm) photometric and spectroscopic observations of the Herschel Space Observatory and draws to this a rich database of a wide ... More