A5064992568- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Scientific Research and Discoveries
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Astro and Planetary Science
- History and Developments in Astronomy
- Dark Matter and Cosmic Phenomena
Max Planck Institute for Extraterrestrial Physics
2014-2023
Pontificia Universidad Católica de Chile
2022-2023
Ludwig-Maximilians-Universität München
2018-2023
Stuttgart Observatory
2021
Optica
2014-2015
Max Planck Society
2014-2015
University of Copenhagen
2013
University of Concepción
2012-2013
The Andromeda galaxy (M31) contains a box/peanut bulge (BPB) entangled with classical (CB) requiring triaxial modelling to determine the dynamics, stellar and dark matter mass. We construct made-to-measure models fitting new VIRUS-W IFU kinematic observations, IRAC-3.6$\mu$m photometry, disc's HI rotation curve. explore parameter space for 3.6$\mu$m mass-to-light ratio $(\Upsilon_{3.6})$, bar pattern speed ($\Omega_p$), mass in composite ($M^B_{DM}$) within 3.2kpc. Considering Einasto...
Context. Giant Low Surface Brightness galaxies, such as Malin 1, host extended stellar and gaseous disks exceeding 100 kpc in radius. Their formation evolution remain debated, with interactions satellite galaxies accretion streams proposed key contributors. 1 has multiple satellites, including 1A, 1B, the newly reported 1C, along eM1 at 350 kpc. Additionally, it exhibits two giant streams, largest extending 200 kpc, likely linked to past interactions. Aims. We investigate orbital dynamics of...
Context. The age–velocity dispersion relation is an important tool to understand the evolution of disc Andromeda galaxy (M 31) in comparison with Milky Way. Aims. We use planetary nebulae (PNe) obtain different radial bins M 31 disc. Methods. separate observed PNe sample based on their extinction values into two distinct age populations velocities our high- and low-extinction PNe, which correspond higher- lower-mass progenitors, respectively, are fitted de-projected elliptical rotational...
Abstract The large-scale gaseous shocks in the bulge of M31 can be naturally explained by a rotating stellar bar. We use gas dynamical models to provide an independent measurement bar pattern speed M31. gravitational potentials our simulations are from set made-to-measure constrained photometry and kinematics. If inclination disk is fixed at i = 77°, we find that low 16–20 km s −1 kpc needed match observed position amplitude shock features, as positions too close major axis high Ω b models....
Aims. We continue the analysis of data set our spectroscopic observation campaign M 31, whose ultimate goal is to provide an understanding three-dimensional structure bulge, its formation history, and composition in terms a classical boxy-peanut bar contributions. Methods. derive simple stellar population (SSP) properties, such as age metallicity α -element overabundance, from measurement Lick/IDS absorption line indices. describe their two-dimensional maps taking into account dust...
We examine the effects of gas-expulsion on initially substructured distributions stars. perform N-body simulations evolution these in a static background potential to mimic gas. remove instantaneously model gas-expulsion. find that exact dynamical state cluster plays very strong role affecting cluster's survival, especially at early times: they may be entirely destroyed or only weakly affected. show knowing both detailed dynamics and relative star-gas can provide good estimate post-gas...
Andromeda is our nearest neighbouring disk galaxy and a prime target for detailed modelling of the evolutionary processes that shape galaxies. We analyse nature M31's triaxial bulge with an extensive set N-body models, which include Box/Peanut (B/P) bulges as well initial classical (ICBs). Comparing IRAC 3.6$\mu m$ data, only one model matches simultaneously all morphological properties bulge, requires ICB B/P 1/3 2/3 total mass respectively. find pure models do not show concentrations high...
Aims. The central region of the giant low-surface-brightness galaxy Malin 1 has long been known to have a complex morphology, with evidence bulge, disc, and potentially bar hosting asymmetric star formation. In this work, we use VLT/MUSE data resolve in order determine its structure. Methods. We used careful light profile fitting every image slice datacube create wavelength-dependent models each morphological component, from which were able cleanly extract their spectra. then kinematics...
We investigate the evolution of mass segregation in initially substructured young embedded star clusters with two different background potentials mimicking gas. Our are virial or subvirial global states and have initial distributions for most massive stars: randomly placed, segregated even inversely segregated. By means N-body simulation, we follow their 5 Myr. measure using minimum spanning tree method ΛMSR an equivalent restricted method. Despite this variety conditions, find that our...
Abstract We report on results from GBT/ARGUS 12 CO(1-0) observations for the giant low surface brightness galaxy Malin 1, which allow us to determine an upper limit its CO mass, and hence molecular gas mass density <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">Σ</mml:mi> </mml:mrow> mathvariant="normal">H</mml:mi> <mml:mn>2</mml:mn> </mml:msub> </mml:math> . Although we performed very deep through 17 hr...
Recent deep photometry of the dwarf spheroidal Ursa Major II's morphology, and spectroscopy individual stars, have provided a number new constraints on its properties. With velocity dispersion $\sim$6 km s$^{-1}$, under assumption that galaxy is virialised, mass-to-light ratio found to be approaching $\sim$2000 - apparently heavily dark matter dominated. Using N-Body simulations, we demonstrate observed luminosity, ellipticity, irregular gradient, can well reproduced through processes...
Dwarf spheroidal (dSph) galaxies are considered the basic building blocks of galaxy formation process in LCDM (Lambda Cold Dark Matter) hierarchical cosmological model. These believed to be most dark matter (DM) dominated systems known, have lowest stellar content, and poor gas. Many theories attempt explain dSph resorting fact that these mainly found orbiting large or invoking other mechanisms interactions. Here we show full set simulation as an extension our fiducial model, where study...
Hercules is a dwarf spheroidal satellite of the Milky Way, found at distance about 138 kpc, and showing evidence tidal disruption. It very elongated exhibits velocity gradient 16 +/- 3 km/s/kpc. Using this data possible orbit has previously been deduced in literature. In study we make use novel approach to find best fit model that follows published orbit. Instead using trial error, systematic order fits multiple observables simultaneously. As such, investigate much wider parameter range...
Aims. The central region of the Giant Low Surface Brightness galaxy Malin 1 has long been known to have a complex morphology with evidence bulge, disc, and potentially bar hosting asymmetric star formation. In this work, we use VLT/MUSE data resolve in order determine its structure. Methods. We careful light profile fitting every image slice datacube create wavelength-dependent models each morphological component, from which could cleanly extract their spectra. then used kinematics emission...
After over three decades of unsuccessful attempts, we report the first detection molecular gas emission in Malin 1, largest spiral galaxy observed to date, and one most iconic giant low surface brightness galaxies. Using ALMA, detect significant $^{12}$CO(J=1-0) galaxy's central region tentatively identify CO across regions on disc. These observations allow for a better estimate H$_2$ mass density, both which are remarkably given scale. By integrating data its HI mass, derive very...
The last few years have seen the discovery of many faint and ultra-faint dwarf spheroidal galaxies around Milky Way. Among these is a pair satellites called Leo IV V. This found at large distances from Way (154 175 kpc, respectively). fairly small difference in radial distance, fact that they also show close projected distance on sky, has led to idea we might be seeing new bound – like Magellanic Clouds. In this paper investigate speculation by means simple integration code (confirming...
ABSTRACT Leo T is a gas-rich dwarf located at $414\, {\rm kpc}$ (1.4Rvir) distance from the Milky Way (MW) and it currently assumed to be on its first approach. Here, we present an analysis of orbits calculated backwards in time for with our new code delorean, exploring range systematic uncertainties, e.g. MW virial mass accretion, M31 potential, cosmic expansion. We discover that tangential velocities Galactic standard-of-rest frame lower than $| \vec{u}_{\rm t}^{\rm GSR}| \le...
We attempt to find a progenitor for the ultra-faint object Segue 1 under assumption that it formed as dark matter free star cluster in past. look orbits, using elongation of on sky tracer its path. Those orbits are followed backwards time starting points our N-body simulations. The successful orbit, with which we can reproduce has proper motion mu_alpha = -0.19 mas/yr and mu_delta -1.9 mas/yr, placing near apo-galacticon today. Our best fitting model an initial mass 6224 Msun scale-length 5.75 pc.
Abstract The formation and evolutionary history of M31 are closely related to its dynamical structures, which remain unclear due high inclination. Gas kinematics could provide crucial evidence for the existence a rotating bar in M31. Using position–velocity diagram [O III ] H i , we able identify clear sharp velocity jump (shock) features with typical amplitude over 100 km s −1 central region (4.6 kpc × 2.3 kpc, or <?CDATA $20^{\prime} \times 10^{\prime} $?> <mml:math...
As the nearest large spiral galaxy, M31 provides a unique opportunity to learn about structure and evolutionary history of this galaxy type in great detail. Among many observing programs aimed at are microlensing studies, which require good three-dimensional models stellar mass distribution. Possible non-axisymmetric structures like bar need be taken into account. Due M31's high inclination, is difficult detect photometry alone. Therefore, detailed kinematic measurements needed constrain...
To understand the history and formation mechanisms of galaxies, it is crucial to determine their current multidimensional structure. In this work, we focus on properties that characterise stellar populations, such as metallicity [ α /Fe] enhancement. We devised a new technique recover distribution these parameters using spatially resolved, line-of-sight averaged data. Our chemodynamical method based made-to-measure framework results in an N -body model for abundance distribution. Following...
The inner kiloparsec regions surrounding sub-Eddington (luminosity less than 10$^{-3}$ in Eddington units, L$_{Edd}$) supermassive black holes (BHs) often show a characteristic network of dust filaments that terminate nuclear spiral the central parsecs. Here we study role and fate these one least accreting BHs known, M31 (10$^{-7}$ using hydrodynamical simulations. evolution streamer gas particles moving under barred potential is followed from distance to After an exploratory initial...
The impact of the dynamical state gas-rich satellite galaxies at early moments their infall into host systems and relation to quenching process are not completely understood low-mass regime. Two such nearby infalling Milky Way (MW) dwarfs Leo T Phoenix located near MW virial radius $414 both which present intriguing offsets between gaseous stellar distributions. Here we hydrodynamic simulations with ramses reproduce observed dynamics T: its $80 stellar- offset 35 older ($ $) younger...