Studying the ISM at $\sim$10 pc scale in NGC 7793 with MUSE -- II. Constraints on the oxygen abundance and ionising radiation escape
Lorenza Della Bruna, Angela Adamo, Janice C. Lee, Linda J. Smith, Mark Krumholz, Arjan Bik, Daniela Calzetti, Anne Fox, Michele Fumagalli, Kathryn Grasha, Matte… 展开作者
Lorenza Della Bruna, Angela Adamo, Janice C. Lee, Linda J. Smith, Mark Krumholz, Arjan Bik, Daniela Calzetti, Anne Fox, Michele Fumagalli, Kathryn Grasha, Matteo Messa, Göran Östlin, Rene Walterbos, Aida Wofford
We study the ionised ISM in NGC 7793 with MUSE/AO, at a spatial resolution of $\sim$ 10 pc. The data are complemented with young star clusters (YSCs), O stars and GMCs observed with HST and ALMA. Using a strong-line method, we find a median $12 + \log(O/H) \sim 8.37$ with a scatter of 0.25 dex, in agreement with previous estimates. The abundance map is rich in substructures, surrounding clusters and massive stars, although clear degeneracies with photoionisation are present. We determine the observed total amount of ionising photons, $Q(H^0)$, from the extinction corrected H$α$ luminosity, and compare it to the expected $Q(H^0)$ obtained by summing the contributions of YSCs and massive stars, to obtain an escape fraction ($f_{esc}$). Overall, we find $f_{esc, HII} = 0.67_{-0.12}^{+0.08}$ for the population of HII regions. We also conclude that the sources of ionisation observed within the FoV are more than sufficient to explain the amount of diffuse ionised gas observed in this region of the galaxy. In general, we find that YSCs located in HII regions have a higher probability to be younger, less massive, and to emit a higher number of ionising photons than clusters in the rest of the field. Finally, we study the optical depth of the regions traced by [SII]/[OIII], finding no systematic trend between the resulting ionisation structure and $f_{esc}$. [abridged]
We present an analysis of the effect of feedback from O- and B-type stars with data from the integral field spectrograph MUSE mounted on the Very Large Telescope of pillar-like structures in the Carina Nebular Complex, one of the most massive star-forming regions in the Galaxy. For the observed pillars, we compute gas electron densities and temperatures maps, produce integrated line and velocity maps of the ionised gas, study the ionisation fronts at the pillar tips, analyse the properties of the single regions, and detect two ionised jets originating from two distinct pillar tips. For each pi…
We map the interstellar medium (ISM) including the diffuse interstellar bands (DIBs) in absorption toward the globular cluster NGC 6397 using VLT/MUSE. This pilot study demonstrates the power of MUSE for mapping the local ISM on very small scales which provides a new window for ISM observations. Assuming the absorbers are located at the rim of the Local Bubble we trace small-scale variations in NaI and KI as well as in several DIBs structures on the order of mpc (milliparsec, a few thousand AU). The sightlines defined by binned stellar spectra are separated by only a few arcseconds and we prob…
We present simulations of the multi-phase interstellar medium (ISM) at solar neighbourhood conditions including thermal and non-thermal ISM processes, star cluster formation, and feedback from massive stars: stellar winds, hydrogen ionising radiation computed with the novel TreeRay radiative transfer method, supernovae (SN), and the injection of cosmic rays (CR). N-body dynamics is computed with a 4th-order Hermite integrator. We systematically investigate the impact of stellar feedback on the self-gravitating ISM with magnetic fields, CR advection and diffusion and non-equilibrium chemical ev…
M^3D: Mosaicking M33 with MUSE datacubes I. Unveiling the diversity of HII regions in M33 with MUSE
Università di Firenze（佛罗伦萨大学）；Center for Astrophysics | Harvard & Smithsonian（哈佛史密森天体物理中心）；National Radio Astronomy Observatory（国家射电天文台）；University of Zagreb（萨格勒布大学）；Ecole Polytechnique Federale de Lausanne（洛桑联邦理工学院）
Using MUSE AO data, we probe the ISM in the local spiral galaxy NGC 7793 at a spatial resolution of $\sim$ 10 pc. We identify HII regions and compile a catalogue of supernova remnants (SNRs), planetary nebulae (PNe) and Wolf Rayet stars (WR). We compute electron densities and temperatures from the [SII]6716/6731 and [SIII]6312/9069 line ratios. We study the properties of the ionised gas through BPT diagrams combined with gas velocity dispersion. We spectroscopically confirm 2 previously detected WR stars and a SNR and report the discovery of 7 WR, 1 SNR, and 2 PNe. The diffuse ionized gas (DIG…
We investigate signatures of a jet-interstellar medium (ISM) interaction using optical integral-field observations of the so-called outer filament near Centaurus A, expanding on previous results obtained on a more limited area. Using the Multi Unit Spectroscopic Explorer (MUSE) on the VLT during science verification, we observed a significant fraction of the brighter emitting gas across the outer filament. The ionized gas shows complex morphology with compact blobs, arc-like structures and diffuse emission. Based on the kinematics, we identified three main components. The more collimated compo…
We use integral field spectroscopy from the PHANGS-MUSE survey, which resolves the ionised interstellar medium at ${\sim}50$ pc resolution in 19 nearby spiral galaxies, to study the origin of the diffuse ionised gas (DIG). We examine the physical conditions of the diffuse gas by first removing morphologically-defined HII regions and then binning the low-surface-brightness areas to achieve significant detections of the key nebular lines. A simple model for the leakage and propagation of ionising radiation from HII regions is able to reproduce the observed distribution of H$α$ in the DIG. Leakin…
The physical origin of the near-ultraviolet MgII emission remains an under-explored domain, contrary to more typical emission lines detected in the spectra of star-forming galaxies. We explore the nebular and physical properties for a sample of 381 galaxies between 0.70 < z < 2.34 drawn from the MUSE Hubble Ultra Deep Survey. The spectra of these galaxies show a wide variety of profiles of the MgII 2796,2803 resonant doublet, from absorption to emission. We present a study on the main drivers for the detection of MgII emission in galaxy spectra. By exploiting photoionization models we verified…
MAUVE-MUSE: Ionization and Kinematic Signatures of Environmental Effects on Virgo Cluster Disks
National Research Council of Canada, Herzberg Astronomy and Astrophysics Research Centre（加拿大国家研究委员会赫茨伯格天体物理学研究中心）；University of Victoria（维多利亚大学）；International Centre for Radio Astronomy Research, The University of Western Australia（西澳大利亚大学国际射电天文研究中心）；ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D)（ARC三维全天空天体物理学卓越中心）；European Southern Observatory（欧洲南方天文台）；School of Astronomy, Institute for research in fundamental sciences (IPM)（基础科学研究院天文学院）
The Ly$α$ line is an important diagnostic for star formation at high redshift, but interpreting its flux and line profile is difficult because of the resonance nature of Ly$α$. Trends between the escape of Ly$α$ photons and dust and properties of the interstellar medium (ISM) have been found, but detailed comparisons between Ly$α$ emission and the properties of the gas in local high-redshift analogs are vital for understanding the relation between Ly$α$ emission and galaxy properties. For the first time, we can directly infer the properties of the ionized gas at the same location and similar s…
The stellar content of young massive star clusters emit large amounts of Lyman continuum photons and inject momentum into the inter stellar medium (ISM) by the strong stellar winds of the most massive stars in the cluster. When the most massive stars explode as supernovae, large amounts of mechanical energy are injected in the ISM. A detailed study of the ISM around these massive cluster provides insights on the effect of cluster feedback. We present high quality integral field spectroscopy taken with VLT/MUSE of two starburst galaxies: ESO 338-IG04 and Haro 11. Both galaxies contain a signifi…
Investigating ionising sources and the complex interstellar medium of GHZ2 at $z=12.3$
INAF Osservatorio Astronomico di Roma（意大利国家天体物理研究所罗马天文台）；Università di Firenze, Dipartimento di Fisica e Astronomia（佛罗伦萨大学物理与天文学系）；INAF – Arcetri Astrophysical Observatory（意大利国家天体物理研究所阿切特里天文台）；European Southern Observatory（欧洲南方天文台）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；Department of Space, Earth, & Environment, Chalmers University of Technology（查尔姆斯理工大学空间、地球与环境系）；NSF’s NOIRLab（美国国家科学基金会NOIR实验室）；Institute of Science and Technology Austria (ISTA)（奥地利科学与技术研究所）；IPAC, California Institute of Technology（加州理工学院IPAC）；Centre for Astrophysics and Supercomputing, Swinburne University of Technology（斯威本科技大学天体物理学与超级计算中心）
We investigate the early impact of single and binary supernova (SN) explosions on dense gas clouds with three-dimensional, high-resolution, hydrodynamic simulations. The effect of cloud structure, radiative cooling, and ionising radiation from the progenitor stars on the net input of kinetic energy, f_kin=E_kin/E_SN, thermal energy, f_therm=E_therm/E_SN, and gas momentum f_P=P/P_SN to the interstellar medium (ISM) is tested. For clouds with n=100 cm^{-3}, the momentum generating Sedov and pressure-driven snowplough phases are terminated early (~ 0.01 Myr) and radiative cooling limits the coupl…
We present spatially resolved measurements of the stellar initial mass function (IMF) in NGC 1399, the largest elliptical galaxy in the Fornax Cluster. Using data from the Multi Unit Spectroscopic Explorer (MUSE) and updated state-of-the-art stellar population synthesis models from Conroy et. al 2018, we use full spectral fitting to measure the low-mass IMF, as well as a number of individual elemental abundances, as a function of radius in this object. We find that the IMF in NGC 1399 is heavier than the Milky Way in its centre and remains radially constant at a super-salpeter slope out to 0.7…
We present a VLT/X-Shooter spectroscopy of the Lyman continuum (LyC) emitting galaxy 'Ion2' at z=3.2121 and compare it to that of the recently discovered strongly lensed LyC-emitter at z=2.37, known as the 'Sunburst' arc. Three main results emerge from the X-Shooter spectrum: (a) the Lya has three distinct peaks with the central one at the systemic redshift, indicating a ionised tunnel through which both Lya and LyC radiation escape; (b) the large O32 oxygen index ([OIII]4959-5007 / [OII]3727-3729) of 9.18(-1.32/+1.82) is compatible to those measured in local (z~0.4) LyC leakers; (c) there are…
Tidal pre-conditioning and ram-pressure stripping in NGC 1427A. Deep VLT/MUSE spectroscopy and FUV-to-radio observations trace a Fornax Cluster dwarf in transformation
Pontificia Universidad Católica de Chile（智利天主教 Pontificia 大学）；Centro Espacial Nacional, Fuerza Aérea de Chile（智利空军国家航天中心）；University of Vienna（维也纳大学）；European Southern Observatory（欧洲南方天文台）；University of Minnesota（明尼苏达大学）；Carnegie Observatories（卡内基观测站）；Gemini Observatory（双子座天文台）；Universidad Diego Portales（迭戈·波特莱斯大学）
Here we describe a new study of the SNRs and SNR candidates in nearby face-on spiral galaxy M83, based primarily on MUSE integral field spectroscopy. Our revised catalog of SNR candidates in M83 has 366 objects, 81 of which are reported here for the first time. Of these, 229 lie within the MUSE observation region, 160 of which have spectra with [SII]:Halpha ratios exceeding 0.4, the value generally accepted as confirmation that an emission nebula is shock-heated. Combined with 51 SNR candidates outside the MUSE region with high [SII]:Halpha ratios, there are 211 spectroscopically-confirmed SNR…
The large field and wavelength range of MUSE is well suited to mapping Galactic planetary nebulae (PN). The bright PN NGC 7009 was observed with MUSE on the VLT during the Science Verification of the instrument in seeing of 0.6". Emission line maps in hydrogen Balmer and Paschen lines were formed from analysis of the MUSE cubes. The measured electron temperature and density from the MUSE cube were employed to predict the theoretical hydrogen line ratios and map the extinction distribution across the nebula. After correction for the interstellar extinction to NGC 7009, the internal dust-to-gas …
We present the ionised gas outflow morphology in the Circinus galaxy using the Narrow Field Mode (NFM) of the MUSE instrument on board the Very Large Telescope (VLT). The NFM observations provide a spatial resolution of $\sim$0.1", corresponding to a physical scale of $\sim$2 pc, one of the highest spatial resolution achievable using ground-based AO-assisted observations in the optical wavelengths. The MUSE observations reveal a collimated clumpy outflow profile originating near the AGN location and extending up to 1.5" ($\sim$30 pc) in the NW direction. The collimated structure then fragments…
Arp220 is the nearest and prototypical ULIRG, and shows evidence of pc-scale molecular outflows in its nuclear regions and strongly perturbed ionised gas kinematics on kpc scales. It is therefore the ideal system for investigating outflows and feedback phenomena in details. We investigate the feedback effects on the Arp220 ISM, deriving a detailed picture of the atomic gas in terms of physical and kinematic properties, with a spatial resolution never obtained before (0.56", i.e. ~ 210 pc). We use optical IFS observations from VLT/MUSE-AO to obtain spatially resolved stellar and gas kinematics,…
We report on the discovery of extended Ly-alpha nebulae at z~3.3 in the Hubble Ultra Deep Field (HUDF, ~ 40 kpc X 80 kpc) and behind the Hubble Frontier Fields galaxy cluster MACSJ0416 (~ 40kpc), spatially associated with groups of star-forming galaxies. VLT/MUSE integral field spectroscopy reveals a complex structure with a spatially-varying double peaked Ly-alpha emission. Overall, the spectral profiles of the two Ly-alpha nebulae are remarkably similar, both showing a prominent blue emission, more intense and slightly broader than the red peak. From the first nebula, located in the HUDF, no…
MUSEQuBES: Physical conditions, origins, and multi-element abundances of the circumgalactic medium of an isolated, star-forming dwarf galaxy at z=0.57
University of Michigan（密歇根大学）；Inter-University Centre for Astronomy & Astrophysics（天文学与天体物理学跨大学中心）；The Observatories of the Carnegie Institution for Science（卡内基科学机构天文台）；University of North Texas（北德克萨斯大学）；Tsinghua University（清华大学）；The University of Chicago（芝加哥大学）；Northwestern University（西北大学）；Tel Aviv University（特拉维夫大学）
A prediction of the classic active galactic nuclei (AGN) unification model is the presence of ionisation cones with different orientations depending on the AGN type. Confirmations of this model exist for present times, but it is less clear in the early Universe. Here, we use the morphology of giant Ly$α$ nebulae around AGNs at redshift z$\sim$3 to probe AGN emission and therefore the validity of the AGN unification model at this redshift. We compare the spatial morphology of 19 nebulae previously found around type I AGNs with a new sample of 4 Ly$α$ nebulae detected around type II AGNs. Using …
European Southern Observatory (ESO)（欧洲南方天文台）；Ritter Astrophysical Research Center, University of Toledo（托莱多大学里特天体物理研究中心）；Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg（海德堡大学天文学中心天文计算研究所）；INAF — Osservatorio Astrofisico di Arcetri（意大利国家天体物理研究所阿切尔蒂天文台）；Department of Astronomy, Ohio State University（俄亥俄州立大学天文学系）；Center for Cosmology and Astroparticle Physics（宇宙学与高能粒子物理中心）；Department of Physics and Astronomy, The Johns Hopkins University（约翰斯·霍普金斯大学物理与天文学系）；International Centre for Radio Astronomy Research, University of Western Australia（西澳大利亚大学国际射电天文学研究中心）；Universität Heidelberg, Zentrum für Astronomie, Institut für Theoretische Astrophysik（海德堡大学天文学中心理论天体物理研究所）
We apply the Tremaine-Weinberg method to 19 nearby galaxies using stellar mass surface densities and velocities derived from the PHANGS-MUSE survey, to calculate (primarily bar) pattern speeds ($Ω_{\rm P}$). After quality checks, we find that around half (10) of these stellar mass-based measurements are reliable. For those galaxies, we find good agreement between our results and previously published pattern speeds, and use rotation curves to calculate major resonance locations (co-rotation radii and Lindblad resonances). We also compare these stellar-mass derived pattern speeds with H$α$ (from…
Directly characterising the first generations of stars in distant galaxies is a key quest of observational cosmology. We present a case study of ID53 at z=4.77, the UV-brightest (but L*) star-forming galaxy at z>3 in the MUSE eXtremely Deep Field with a mass of $10^9$ M$_{\odot}$. In addition to very strong Lyman-$α$ (Ly$α$) emission, we clearly detect the (stellar) continuum and an NV P-Cygni feature, interstellar absorption, fine-structure emission and nebular CIV emission lines in the 140 hr spectrum. Continuum emission from two spatially resolved components in Hubble Space Telescope data a…
We present IFU observations with MUSE@VLT and deep imaging with FORS@VLT of a dwarf galaxy recently formed within the giant collisional HI ring surrounding NGC 5291. This TDG-like object has the characteristics of typical z=1-2 gas-rich spiral galaxies: a high gas fraction, a rather turbulent clumpy ISM, the absence of an old stellar population, a moderate metallicity and star formation efficiency. The MUSE spectra allow us to determine the physical conditions within the various complex substructures revealed by the deep optical images, and to scrutinize at unprecedented spatial resolution the…
We investigate the ionised gas kinematics, physical properties and chemical abundances of SDSS$J$142947, a Green Pea galaxy at redshift z$\sim$0.17 with strong, double-peak Ly$α$ emission and indirect evidence of Lyman continuum (LyC) leakage. Using high-dispersion spectroscopy, we perform a multi-component analysis of emission-line profiles. Our model consistently fits all lines as a narrow component with intrinsic velocity dispersion $σ\sim$40 km s$^{-1}$, and two broader blue-shifted components with $σ\sim$90 km s$^{-1}$ and $\sim$250 km s$^{-1}$. We find electron densities and temperatures…
Local examples of jet-induced star formation lend valuable insight into its significance in galaxy evolution and can provide important observational constraints for theoretical models of positive feedback. Using optical integral field spectroscopy, we present an analysis of the ISM conditions in Minkowski's Object ($z = 0.0189$), a peculiar star-forming dwarf galaxy located in the path of a radio jet from the galaxy NGC 541. Full spectral fitting with PPXF indicates that Minkowski's Object primarily consists of a young stellar population $\sim 10$ Myr old, confirming that the bulk of the objec…
Aims. As a new approach to the study of resolved stellar populations in nearby galaxies, our goal is to demonstrate in NGC300 that integral field spectroscopy with high spatial resolution and excellent seeing conditions reaches an unprecedented depth in severely crowded fields. Methods. MUSE observations with seven pointings in NGC300 have resulted in datacubes that are analyzed in four ways: (1) PSF-fitting 3D spectroscopy with PampelMUSE yields deblended spectra of individually distinguishable stars. The technique also provides samples of planetary nebulae that are complete down to m5007=28.…
We present MUSE integral field data of two HII region complexes in the Large Magellanic Cloud (LMC), N44 and N180. Both regions consist of a main superbubble and a number of smaller, more compact HII regions that formed on the edge of the superbubble. For a total of 11 HII regions, we systematically analyse the radiative and mechanical feedback from the massive O-type stars on the surrounding gas. We exploit the integral field property of the data and the coverage of the HeII$λ$5412 line to identify and classify the feedback-driving massive stars, and from the estimated spectral types and lumi…
Spatially resolved studies of high redshift galaxies, an essential insight into galaxy formation processes, have been mostly limited to stacking or unusually bright objects. We present here the study of a typical (L$^{*}$, M$_\star$ = 6 $\times 10^9$ $M_\odot$) young lensed galaxy at $z=3.5$, observed with MUSE, for which we obtain 2D resolved spatial information of Ly$α$ and, for the first time, of CIII] emission. The exceptional signal-to-noise of the data reveals UV emission and absorption lines rarely seen at these redshifts, allowing us to derive important physical properties (T$_e\sim$15…
Polycyclic aromatic hydrocarbons (PAHs) play a critical role in the reprocessing of stellar radiation and in balancing the heating and cooling processes in the interstellar medium (ISM), but appear to be destroyed in HII regions. However, the mechanisms driving their destruction are still not completely understood. Using PHANGS-JWST and PHANGS-MUSE observations, we investigate how the PAH fraction changes in about 1500 HII regions across four nearby star-forming galaxies (NGC 628, NGC 1365, NGC 7496, IC 5332). We find a strong anti-correlation between the PAH fraction and the ionization parame…
Feedback to the interstellar medium (ISM) from ionising radiation, stellar winds and supernovae is central to regulating star formation in galaxies. Due to their low mass ($M_{*} < 10^{9}$\,M$_\odot$), dwarf galaxies are particularly susceptible to such processes, making them ideal sites to study the detailed physics of feedback. In this perspective, we summarise the latest observational evidences for feedback from star forming regions and how this drives the formation of 'superbubbles' and galaxy-wide winds. We discuss the important role of external ionising radiation -- 'reionisation' -- for…
We investigated the interstellar medium (ISM) properties in the central regions of nearby Seyfert galaxies characterised by prominent conical or bi-conical outflows belonging to the MAGNUM survey by exploiting the unprecedented sensitivity, spatial and spectral coverage of the integral field spectrograph MUSE at the Very Large Telescope. We developed a novel approach based on the gas and stars kinematics to disentangle high-velocity gas in the outflow from gas in the disc to spatially track the differences in their ISM properties. This allowed us to reveal the presence of an ionisation structu…
SECCO1 is an extremely dark, low-mass (M_star=10^5 M_sun), star-forming stellar system lying in the Low Velocity Cloud (LVC) substructure of the Virgo cluster of galaxies, and hosting several HII regions. Here we review our knowledge of this remarkable system, and present the results of (a) additional analysis of our panoramic spectroscopic observations with MUSE, (b) the combined analysis of Hubble Space Telescope and MUSE data, and (c) new narrow-band observations obtained with OSIRIS@GTC to search for additional HII regions in the surroundings of the system. We provide new evidence supporti…
Context: Lyman $α$ blobs (LABs) are large-scale radio-quiet Lyman $α$ (Ly$α$) nebula at high-$z$ that occur predominantly in overdense proto-cluster regions. Especially the prototypical SSA22a-LAB1 at $z=3.1$ has become an observational reference for LABs across the electromagnetic spectrum. Aims: We want to understand the powering mechanisms that drive the LAB to gain empirical insights into galaxy formation processes within a rare dense environment at high-$z$. Methods: LAB 1 was observed for 17.5h with the VLT/MUSE integral-field spectrograph. We produced optimally extracted narrow band ima…
Stellar feedback plays a significant role in modulating star formation, redistributing metals, and shaping the baryonic and dark structure of galaxies -- however, the efficiency of its energy deposition to the interstellar medium is challenging to constrain observationally. Here we leverage HST and ALMA imaging of a molecular gas and dust shell ($M_{H2} \sim 2\times 10^{5} ~{\rm M}_{\odot}$) in an outflow from the nuclear star forming ring of the galaxy NGC 3351, to serve as a boundary condition for a dynamical and energetic analysis of the outflowing ionised gas seen in our MUSE TIMER survey.…
We present XSHOOTER observations with previous ALMA, MUSE and $HST$ observations to study the nature of radio-jet triggered star formation and the interaction of radio jets with the interstellar medium in the brightest cluster galaxy (BCG) in the Abell 1795 cluster. Using $HST$ UV data we determined an ongoing star formation rate of 9.3 M$_\odot$ yr$^{-1}$. The star formation follows the global Kennicutt-Schmidt law, however, it has a low efficiency compared to circumnuclear starbursts in nearby galaxies with an average depletion time of $\sim$1 Gyr. The star formation and molecular gas are of…
The SPHINX public data release. II. Using low-ionisation absorption lines and dust attenuation to predict Lyman continuum escape
Kapteyn Astronomical Institute, University of Groningen（格罗宁根大学卡普坦天文研究所）；Centre de Recherche Astrophysique de Lyon UMR5574, Univ Lyon1, ENS de Lyon, CNRS（里昂天体物理研究中心）；Observatoire de Genève, Université de Genève（日内瓦大学日内瓦天文台）；Aix Marseille Univ., CNRS, CNES, Laboratoire d’Astrophysique de Marseille（马赛天体物理实验室）；Department of Astronomy, The University of Texas at Austin（德克萨斯大学奥斯汀分校天文学系）；Cosmic Frontier Center, The University of Texas at Austin（德克萨斯大学奥斯汀分校宇宙前沿中心）；Department of Astronomy, Oskar Klein Centre, Stockholm University（斯德哥尔摩大学奥斯卡·克莱因中心天文学系）；LUX, Observatoire de Paris, Université PSL, Sorbonne Université, CNRS（巴黎天文台）；Department of Astronomy, Yonsei University（延世大学天文学系）
We present a large VLT/MUSE mosaic (3.8 x 3.8 kpc) of the nearby spiral galaxy M83, with a spatial resolution ~20 pc. We obtained the kinematics of the stars and ionised gas, and compared them with molecular gas kinematics from ALMA CO(2-1). We separated the ionised gas into HII regions and diffuse ionised gas (DIG) and determined the fraction of Ha luminosity originating from the DIG (f_DIG). We observe that both stars and gas trace the galactic disk rotation, as well as a fast-rotating nuclear component, likely connected to secular processes driven by the galactic bar. In the gas kinematics,…
We present maps tracing the fraction of dust in the form of polycyclic aromatic hydrocarbons (PAHs) in IC 5332, NGC 628, NGC 1365, and NGC 7496 from JWST/MIRI observations. We trace the PAH fraction by combining the F770W ($7.7~μ$m) and F1130W ($11.3~μ$m) filters to track ionized and neutral PAH emission, respectively, and comparing the PAH emission to F2100W which traces small, hot dust grains. We find average $R{\rm_{PAH} = (F770W+F1130W)/F2100W}$ values of 3.3, 4.7, 5.1, and 3.6 in IC 5332, NGC 628, NGC 1365, and NGC 7496, respectively. We find that H II regions traced by MUSE H$α$ show a s…
The early-type galaxy NGC 1316 hosts about 10^7 solar masses of dust within a central radius of 5 kpc. These prominent dust structures are believed to have an external origin, which is also a popular interpretation for other dusty early-type galaxies. We use archival Hubble Space Telescope/ACS data to construct colour maps that delineate the dust pattern in detail, and we compare these data with maps constructed with data from MUSE of the VLT at the European Southern Observatory. Twelve MUSE pointings in wide field mode form a mosaic of the central 3.3'x2.4'. We use the tool PyParadise to fit …
The spatial distribution of metals reflects, and can be used to constrain, the processes of chemical enrichment and mixing. Using PHANGS-MUSE optical integral field spectroscopy, we measure the gas phase oxygen abundances (metallicities) across 7,138 HII regions in a sample of eight nearby disc galaxies. In Paper I (Kreckel et al. 2019) we measure and report linear radial gradients in the metallicities of each galaxy, and qualitatively searched for azimuthal abundance variations. Here, we examine the two-dimensional variation in abundances once the radial gradient is subtracted, Delta(O/H), in…
