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recently, lee et al. (2018) have reported the observational evidences that galactic bulge consists of stellar populations originated from milky way globular clusters (mwgcs). motivated by this, here we present the evolutionary population synthesis (eps) for galactic bulge with the realistic treatment of individual vari... | bulge and globular cluster connection: evolutionary population synthesis with multiple populations |
the most promising probe into compact binary formation and evolution will be the populations resolved by both gravitational wave (gw) and electromagnetic (em) observatories. as with any observation, theoretical models must be characterized to gain a fuller understanding of the underlying physics governing the observed ... | simulating binary populations in the milky way |
as part of the fourth generation of sloan digital sky survey (sdss-iv), the manga stellar library (mastar) project is constructing a large, well-calibrated, high quality empirical stellar library with more than 10,000 stars covering the wavelength range from 3622 to 10,354a at a resolution of r~2000. the spectra are ta... | mastar --- a large and comprehensive empirical stellar spectral library |
populations of massive stars are directly reflective of the physics of stellar evolution. counting subtypes of massive stars and ratios of massive stars in different evolutionary states have been used ubiquitously as diagnostics of age and metallicity effects. while the binary fraction of massive stars is significant, ... | measuring the massive star binary fraction with stellar population diagnostics |
we have proposed that high field magnetic white dwarfs are the result of close binary interaction and merging during common envelope evolution. we now synthesise a population of binary systems to investigate the hypothesis that the magnetic fields in the accreting magneticwhite dwarf in cataclysmic variables also origi... | modelling of the magnetic field distribution in the magnetic cataclysmic variables |
the central galaxies in galaxy groups and clusters rank among the most massive galaxies in the universe, but a significant fraction of their stellar mass lies in the low surface-brightness and hard-to-detect outer envelope. we use new deep optical and mid-infrared imaging of a sample of more than 20,000 central galaxie... | mapping the stellar mass content of central galaxies in dark matter halos |
the standard explanation for the origin of the multiple populations in gcs is that of self-enrichment, where stars of a 1st generation expel their stellar ejecta which mixes with primordial material and eventually forms a second (and further) generation of stars. popular polluting stars are agbs, fast-rotating massive ... | a general abundance problem for all self-enrichment scenarios for the origin of multiple populations in globular clusters |
post asymptotic giant branch (pagb) stars are luminous objects (103 - 104l⊙) in final stages of their evolution before reaching the white dwarf cooling sequence. they are an important key to understand galaxy evolution since they are hot enough to contribute to the uv excess in old stellar systems. binary interactions ... | pagb stars in binary stellar population synthesis model |
the evolution of binary-star systems vary from that of single stars as they can interact with their companions. this leads to mass loss, mass gain, or stellar mergers. we now know that most massive stars are binary stars. in nearby galactic open clusters as many as 70% of massive stars interact with a binary companion ... | the impact of interacting binary stars on core-collapse supernovae and emission nebulae |
we obtain estimates of resolved stellar mass for galaxies in the sdss-iv/manga integral-field-spectroscopic survey, using a principal component analysis (pca) model trained on synthetic star-formation histories. to examine the differing systematics resulting from dynamical- and stellar-population-synthesis-derived stel... | sdss-iv/manga: a pca-based approach to stellar mass estimation for ifs observations |
near-infrared starlight is a good tracer of stellar mass. this is expected from the perspective of stellar population synthesis, and appears to be the case for scaling relations: the stellar mass and baryonic tully-fisher relations have very small scatter when spitzer 3.6 micron data are used to estimate stellar mass. ... | calibrating the stellar mass of star forming galaxies |
metal poor star forming galaxies sit on the far left wing of the bpt diagram just below traditional demarcation lines. the basic approach to reproducing their emission lines by coupling photoionization models to stellar population synthesis models underestimates the observed [o iii] / hβ ratio by a factor 0.3-0.5 dex. ... | addressing the [o iii] / hβ offset in metal poor star forming galaxies found in the resolve survey and eco catalog |
white dwarfs are natural cosmochronometers, and this allows us to use them to study relevant properties of the galaxy, such as its age or its star formation rate history. here we present a population synthesis study of the white dwarf population within 40 pc from the sun, and compare the results of this study with the ... | a population synthesis study of the local white dwarf population |
we present 3 representative cases from a sample of 16 local brightest cluster galaxies observed using integral field spectroscopy. the observations extend to nearby neighbours and into the intracluster light (icl). population synthesis modeling shows that the icl is younger and more metal poor compared to the bcg core ... | stellar populations of brightest cluster galaxies and intracluster light |
the magellanic clouds (mcs) are two small galaxies that are among the nearest to the milky way. because they are nearby, the clouds are well suited to careful examination by measurement of resolved stellar populations and other techniques, yet the scientific under- standing of the clouds is only beginning to come into ... | populations and history in the outer limits of the magellanic system |
the attenuation of star light in galaxies by dust imposes a major uncertainty in the derivation of galaxy physical properties. as we show in this proposal, for example, incorrect assumptions about attenuation laws in sed fitting can result in errors of 0.3 dex in the derived m* and sfr from galaxies. while hst observat... | modeling dust attenuation laws in galaxies with cosmological zoom simulations |
a galaxy's spectrum is the sum of light emitted by stars and gas, modulated by intervening dust. translating between the observed flux from galaxies and meaningful astrophysical quantities relies on "stellar population synthesis" (sps) models. these models include descriptions for the light produced by stars and dust i... | building galaxy models with self-consistent prescriptions for stellar and nebular emission |
recent nustar-swift observations revealed that a single resolved x-ray source, swift j0042.6+4112, with lx of a few times 1038 erg/s dominates the hard x-ray emission from the andromeda galaxy. hst-based stellar population synthesis modeling combined with the 0.5-50 kev spectral shape suggests that this might be an x-r... | detection of potential periodicities in the unique hard x-ray source swift j0042.6+4112, dominating the hard x-ray emission in m31 |
recent nustar-swift observations revealed that a single resolved x-ray source, swift j0042.6+4112, with lx of a few times 1038 erg/s dominates the hard x-ray emission from the andromeda galaxy. hst-based stellar population synthesis modeling combined with the 0.5-50 kev spectral shape suggest that this might be an x-ra... | timing analysis of a unique hard x-ray source, swift j0042.6+4112, in m31 |
the small magellanic cloud (smc) has been the subject of systematic x-ray surveys over the past two decades, which have yielded a rich population of high-mass x-ray binaries consisting predominantly of be/x-ray binaries. we present results from our deep chandra survey of the smc which targeted regions with stellar popu... | a deep survey of the x-ray binary populations in the smc |
the primordial scenario and the initial conditions that gave rise to the solar system are still under debate. a population synthesis analysis of the formation and evolution of solar system analogs (ssa) is a possible mechanism to understand our own solar system. from a new numerical code called planetalp, which is able... | population synthesis analysis: determining parameters and favorable scenarios for the formation of solar system analogs |
for over a decade now spectral synthesis methods have been applied to recover the fossil record of galaxy evolution encoded in their optical spectra. in its many variants, this powerful tool has helped to digest the avalanche of data, transforming observed spectra onto a long and informative suite of physical propertie... | steps towards a more realistic inverse modeling of galaxy data with starlight |
the blue compact dwarf galaxy ngc 5253 hosts a very young starburst containing twin nuclear star clusters. calzetti et al. (2015) find that the two clusters have an age of 1 myr, in contradiction to the age of 3-5 myr inferred from the presence of wolf-rayet (w-r) spectral features. we use hubble space telescope (hst) ... | the very massive star content of the nuclear star clusters in ngc 5253 |
measurements of exoplanet atmosphere composition provide an unparalleled window into planetary nature and origins. water in particular is an important tracer of the planet formation process because it is a dominant component by mass of icy planetesimals. exoplanets provide the opportunity to measure water abundance ove... | the kelt-11b opportunity: measuring the atmospheric water abundance for a sub-saturn-mass planet around a metal-rich star |
the first deep spectra of reionization-era galaxies have revealed strong uv nebular emission in high-ionization lines. this is in striking contrast to massive galaxies at lower redshifts, where emission from ciii], oiii], heii, and civ is rarely seen. these lines will likely be the only probe available for the most dis... | extreme wolf-rayet galaxies with hst/cos: understanding ciii] emission in the reionization era |
we propose to complete the census of cosmic black hole growth by measuring luminous and/or distant quasars using spitzer, herschel, chandra and xmm-newton imaging in stripe 82 the deepest sloan digital sky survey field, and now the premier legacy field among 100 deg2 survey areas. these extensive ancillary data offer u... | obscured black hole growth at high redshift and high luminosity |
in the galaxy parameter fitting by means of stellar population synthesis, it is found that compared with the evolutionary population synthesis (eps) model without binary interactions, the stellar age and metallicity of a galaxy derived from the eps model with binary interactions are larger. but, we are still unclear ho... | effects of binary interactions on the early-type galaxy chemical evolution and gas cooling functiontwo |
the cygnus ob2 association is located in the galactic cygnus x region at a distance of 1.4 kpc, making it one of the closest young massive stellar clusters. cyg ob2 is not only very rich in stellar density but also in its diversity. it is known to contain a rich population of massive stars including almost 2600 ob star... | non-thermal emission from the massive stellar association cygnus ob2 |
there are two categories of elements for which abundances are measured in planetary nebulae (pne). the first are species whose abundances may be modified by nuclear reactions in the star prior to pn formation, such as he, c, n, and nuclei made by slow neutron captures (karakas & lattanzio 2014, pasa, 31, 30). in co... | population signatures in planetary nebulae from abundances of fe-group and neutron-capture elements |
measuring the fraction of high-mass x-ray binaries (hmxbs) that harbors a black hole (bh) rather than a neutron star (ns) can improve our understanding of the role of stellar winds and mass transfer in the evolution of massive stars and help constrain estimates of the numbers of ns/bh and bh/bh binaries in the galaxy, ... | does the hmxb igr j18214-1318 contain a black hole or neutron star? |
the discovery of multiple stellar populations in the milky way globular clusters has stimulated a great deal of researches on the helium enhanced stellar populations. here, we present the evolutionary population synthesis models for integrated spectro-photometric evolution of simple stellar populations (ssps) with vari... | the evolutionary population synthesis model for helium-enhanced stellar populations |
over a dozen ultracool dwarfs (ucds), which inhabit the boundary between low mass stars and brown dwarfs, are known sources of radio activity. this activity consists of highly ( 100%) circularly polarized, high brightness temperature radio flares thought to be caused by the electron cyclotron maser operating in kg magn... | intel secure key-powered radio-flaring ultracool dwarf population synthesis |
we employed apache point observatory triplespec near infrared spectra (nir, ∼1.0 μm-2.4μm) of 6 early-type galaxies, and one spiral galaxy, to test 5 evolutionary population synthesis models in the near infrared. we used 3 low spectral resolution and 2 high spectral resolution bases of simple stellar populations (ssps)... | testing evolutionary population synthesis models with early type galaxies in the near infrared |
ω centauri is a massive, old, globular cluster that has been extensively studied over the years because of its peculiar color-magnitude diagram. specifically, the color-magnitude diagram of this cluster has evident signs of the existence of multiple populations, which are clearly seen in the morphologies of both the ma... | the double cooling sequence of the globular cluster ω centauri |
we present a sample of “orphan” globular clusters (gcs) with previously unknown parent galaxies, which we determine to be remote satellites of m87, a massive elliptical galaxy at the center of the virgo cluster of galaxies. because gcs were formed in the early universe along with their original parent galaxies, which w... | study of remote globular cluster satellites of m87 |
alma observations now routinely provide sensitive, cloud-scale (<50 pc), multi-tracer diagnostics of molecular gas and star formation in nearby galaxies. this wealth of information plus the ability to cover large populations of extragalactic star forming clouds is sharpening our understanding of how star formation i... | alma's view of molecular gas and star formation in nearby galaxies |
we discuss estimates of the rates of mergers of binary systems composed of neutron stars and/or stellar mass black holes. we use the startrack population synthesis code, and make predictions for the detection rate of compact binary coalescences with the advanced ligo/virgo gravitational wave detectors. because these in... | predicting binary merger event rates for advanced ligo/virgo |
hst has invested thousands of orbits to complete multi-wavelength surveys of high-redshift galaxies including the deep fields, cosmos, 3d-hst and candels. over the next few years, jwst will undertake complementary, spatially-resolved infrared observations. cosmological simulations are the most powerful tool to make det... | combining statistical samples of resolved-ism simulated galaxies with realistic mock observations to fully interpret hst and jwst surveys |
in the limit of extremely rapid mass transfer, the response of a donor star in an interacting binary becomes asymptotically one of adiabatic expansion. we survey here adiabatic mass loss from population i stars (z=0.02) of mass 0.10m⊙-100m⊙ from the zero-age main sequence to the base of the giant branch, or to central ... | vizier online data catalog: adiabatic mass loss in binary stars. ii. (ge+, 2015) |
the core-degenerate (cd) scenario has been proposed as an alternative way for the production of type ia supernovae (sne ia). in this scenario, sne ia are formed at the final stage of common-envelope evolution from a merger of a carbon-oxygen white dwarf (co wd) with the co core of an asymptotic giant branch companion. ... | binary population synthesis for the core-degenerate scenario of sn ia progenitors |
dwarf galaxies are typically very faint, and are therefore hard to find. given that, what are our chances of finding their distant ancestors, located billions of light-years away? a recent study aims to find out.ancient counterpartsdwarf galaxies are a hot topic right now, especially as we discover more and more of the... | the hunt for dwarf galaxies' ancestors |
the apache point observatory galactic evolution experiment (apogee) of the sloan digital sky survey iv has measured high resolution (r~22,500), near-infrared (1.51-1.70 µm) spectra for nearly 100,000 stars within the milky way galaxy. while the apogee experiment was designed to research galactic structure by targeting ... | modeling stellar parameters for high resolution late-m and early-l dwarf sdss/apogee spectra |
non-lte emission can be much greater than the intrinsic planetary emission due to stellar flux amplifications via fluorescence cascades, and it may provide a new means to characterize the composition of exoplanets. are we properly interpreting exoplanet spectra using current emission models? can molecular signatures be... | modeling of non-equilibrated emission from exoplanets for a broad range of temperatures, host stars and molecules (h2o, ch4, co2, co, nh3, hcn) |
most of the galactic black hole (bh) x-ray binary systems are low-mass x-ray binaries (lmxbs). although the formation of these systems has been extensively investigated, some crucial issues remain unresolved. the most noticeable one is that, the low-mass companion has difficulties in ejecting the tightly bound envelope... | formation of galactic black hole low-mass x-ray binaries |
elements with atomic number greater than z=26 (the iron peak) cannot be formed through fusion in a star's core; the majority of these elements are produced through one of two neutron-capture processes. early in the history of the galaxy, the rapid neutron-capture process (r-process) is believed to be responsible for th... | la and eu abundances in metal-poor halo stars |
the identification of active galactic nuclei (agn) and their classification as obscured or unobscured are important parameters for the explanation of the x-ray background and its synthesis models. agn detection and classification is expected to be sensitive to its environment (obscuration, host galaxy starlight, star-f... | investigations of agn populations through x-ray and optical surveys |
this thesis revolves around the topic of black holes (bhs) in x-ray binaries (xrbs). the trigger of this work was to understand how stellar-mass bhs form, a question which we tackled both with theoretical as well as observational studies. the formation mechanism of bhs is an unsolved problem in high-energy astrophysics... | the formation of black-holes derived from x-ray binaries |
we analyse the star formation histories (sfh) of m > 10^{10} m_⊙ read and dead galaxies at intermediate redshift (z=1.0-1.5). current hierarchical models of galaxy formation predict many less massive high-z systems than observed. by combining shards deep spectro-photometric optical data (25 contiguous osiris/gtc med... | the star formation history of read and dead galaxies at z=[1.0--1.5] |
the majority of young massive stars are found in close binary systems. recently, dedicated observing campaigns have provided strong constraints on the binary fraction as well as the distribution of the parameters that characterize the binary systems: the masses of both components, the orbital period and eccentricities.... | formation of cold clumps and filaments around superbubbles |
the majority of young massive stars are found in close binary systems. recently, dedicated observingcampaigns have provided strong constraints on the binary fraction as well as the distribution of the parameters thatcharacterize the binary systems: the masses of both components, the orbital period and eccentricities. m... | massive binaries as progenitors for stellar explosions |
the large diversity of exoplanets in terms of irradiation temperature, gravity and chemical composition discovered around stars with different properties call for the development of fast, accurate and versatile atmospheric models. we derive a new, non-grey analytical model for the thermal structure of irradiated exopla... | non-grey thermal effects in irradiated planets atmospheres |
we present results of an investigation into the photoionization (pi), recombination, and electron-impact excitation properties of low-charge br and rb ions. br and rb are among the relatively few neutron(n)-capture elements (atomic number z > 30) that have been detected in planetary nebulae (pne). their abundances c... | atomic data for nebular abundance determinations: photoionization, recombination, and collisional excitation of rubidium and bromine ions |
the atmospheres of extremely close in extrasolar giant planets, or "hot jupiters," are beginning to be analyzed as a population. synthesizing observations of many different planets provides insight into the nature of the atmospheric circulation of these objects. notably, the dayside-to-nightside brightness temperature ... | a predictive theory for the atmospheric circulation of hot jupiters |
using spectroscopic data from the mosfire deep evolution field (mosdef) survey we study stellar population properties of distant galaxies. the mosdef survey is a rest-frame optical spectroscopic survey of ~1500 galaxies in three different redshift regimes: 1.37-1.70, 2.09-2.61, and 2.95-3.80. we utilize the mosdef surv... | deriving stellar population models of galaxies through spectroscopic analysis |
we propose to observe the spectacular great circle stellar stream around sprc047, an edge-on galaxy at redshift 0.03. our aim is to study the origin of the multiple stellar streams with stellar clumps (possibly multiple progenitors) using stellar population synthesis fits to combined spitzer/irac 3.6 micron and existin... | spitzer/irac study of the origin of the stellar streams in sprc047 |
we perform binary evolution calculations on helium star - carbon-oxygen white dwarf (co wd) binaries using the one-dimensional stellar evolution code mesa. this channel may contribute significantly to thermonuclear supernovae at short delay times. we examine the thermal-timescale mass transfer from a 1.1 - 2.0 m⊙ heliu... | evolution of helium star - white dwarf binaries leading up to thermonuclear supernovae |
we can learn a lot about the formation of compact objects, such as neutron stars and black holes, by studying the x-ray emission from accreting systems in nearby star-forming galaxies. the harder (e>10 kev) x-ray emission in particular allows strong discrimination among the accretion states and compact object types.... | young black hole and neutron star systems in the nearby star-forming galaxy m33: the nustar view |
we propose joint chandra/hst observations (chandra: 150 ks) of ngc 2276 to obtain a complete picture of its luminous high-mass x-ray binary (hmxb) population. interaction of ngc 2276 with the intergalactic medium has ignited a recent, asymmetric burst of star formation. there is tantalizing evidence in existing observa... | using star formation in ngc 2276 as an x-ray binary chronometer |
wd+agb star systems have been suggested as an alternative way for producing type ia supernovae (sne ia), known as the core-degenerate (cd) scenario. in the cd scenario, sne ia are produced at the final phase during the evolution of common-envelope through a merger between a carbon-oxygen (co) wd and the co core of an a... | wd+agb star systems as the progenitors of type ia supernovae |
recently, a sub-arcsecond resolution survey of the dust continuum emission from nearby protoplanetary disks, conducted with the submillimeter array showed a strong correlation between the sizes and luminosities of the disks. performing models of gas and dust disk evolution, we recreate this relation using a large grid ... | disk population synthesis |
we use spectroscopic observations to investigate galaxies from the age of reionization to the peak of star formation, and the local universe. this thesis presents three projects to better understand characteristics of galactic feedback, i.e., how it regulates galactic gas flows. we used deep absorption line spectroscop... | spectroscopy of galaxies: evolution of escape fractions, metallicity gradients and stellar metallicity |
the field of gravitational-wave astronomy has been initiated by the recent observations of binary black hole mergers. these observations illuminate objects that are inaccessible with electromagnetic telescopes, and open inquiries as to how heavy binary black hole systems form and merge. two possible formation channels ... | discriminating formation channels of binary black hole systems with advanced ligo |
peculiar groups of x-ray emitting isolated neutron stars (inss), which include magnetars, the "magnificent seven", and central compact objects in supernova remnants, escape detection in standard pulsar surveys. yet, they constitute a key element in understanding extreme phenomena unobserved in the normal pulsar populat... | follow-up of isolated neutron star candidates from the erosita survey |
in 1919 james jeans published the book problems of cosmogony and stellar dynamics in which he summarized his work on dynamics of stellar systems based on his papers published from 1915 onwards. to mark the centenary of this publication we present here one application of his work relevant for contemporary research of ga... | dark matter in massive early-type galaxies: 100 years of the jeans equations |
pair production within the cores of massive stars is predicted to lead to instabilities that result in a lack of remnant black holes with masses between 45 and 135 solar masses. the detection of gravitational waves due to binary black hole mergers allows for a new way to explore this mass gap and its properties. with t... | implementing pair instability processes into cosmic |
the rapid neutron capture process (r-process) is responsible for the synthesis of approximately half of the abundance of the heavy elements. the recent ligo and virgo gravitational-wave detection from two colliding neutron stars combined with the wealth of electromagnetic follow-up measurements across the electromagnet... | properties of neutron-rich 71 , 72 , 73ni |
our first deep observations of high redshift galaxies revealed exceptionally strong high-ionization nebular emission lines. characterizing and describing the detailed observations of the earliest galaxies with jwst and future extremely large telescopes will hinge on our understanding of these lines. however, current st... | pulling back the curtain veiling extreme uv galaxies: revealing the mysterious sources of he ii emission |
we present the bidimensional exploration of the warm-temperature ionised gas (betis) project, designed for the spatial and spectral study of the diffuse ionised gas (dig) in a selection of 265 spiral galaxies observed with muse, of different morphologies and an average spatial resolution of 274 pc (z<0.06). our main... | betis: bidimensional exploration of the warm-temperature ionised gas i. sample presentation and first results |
we propose nircam+miri multi-band imaging for the evil eye galaxy (m64), a unique nearby merger-induced starburst system. we will uncover a large population of deeply embedded star clusters in the dusty, compact, inner disk of m64, where the high gas surface densities and complex orbital configurations provide very fav... | beholding star cluster formation, feedback, and evolution with the 'evil eye' |
we study the local environmental properties of 418 supernovae (sne) of all types using data from the javalambre photometric local universe survey (j-plus), which includes 5 broad- and 7 narrow-band imaging filters, using two independent analyses: 1) the normalized cumulative rank (ncr) method, utilizing all 12 single b... | supernova environments in j-plus. normalized cumulative rank distributions and stellar population synthesis, combining narrow- and broad-band filters |
wind roche-lobe overflow (wrlof) is a mass-transfer mechanism for stellar binaries wherein the wind acceleration zone of the donor star exceeds its roche lobe radius, allowing material to be transferred to the accretor. wrlof may explain characteristics observed in blue lurkers and blue stragglers, such as their fast r... | the effects of wind roche-lobe overflow on binary evolution |
in this study we define a new sample of distant powerful radio galaxies in order to study their host galaxy properties and provide targets for future observations of h i absorption with new radio telescopes and to understand the fuelling and feedback from such sources. we have cross-matched the sydney university molong... | a new sample of southern radio galaxies: host-galaxy masses and star-formation rates |
the cornerstone mission of the european space agency, gaia, has revealed properties of 260 000 white dwarfs in the galaxy, allowing us for the first time to constrain the evolution of white dwarfs with a large sample. complementary surveys (corot, kepler, k2, apogee and gaia-eso), will revolutionize our understanding o... | new population synthesis approach: the golden path to constrain stellar and galactic physics |
dsps synthesizes stellar populations, leading to fully-differentiable predictions for galaxy photometry and spectroscopy. the code implements an empirical model for stellar metallicity, and it also supports the diffstar (ascl:2302.012) model of star formation and dark matter halo history. dsps rapidly generates and sim... | dsps: differentiable stellar population synthesis |
as gravitational wave detectors improve, observations of black hole (bh) mergers will provide the joint distribution of their masses and spins. this will be a critical benchmark to validate formation scenarios. merging binary bhs formed through isolated binary evolution require both components to be stripped of their h... | an upper limit on the spins of merging binary black holes formed through binary evolution |
we characterize in detail the radial structure of the stellar population properties of 300 galaxies in the nearby universe, observed with integral field spectroscopy in the califa survey. the sample covers a wide range of hubble types, from spheroidal to spiral galaxies, ranging in stellar masses from $m_\star \sim 10^... | the califa survey across the hubble sequence: how galaxies grow their bulges and disks |
the study of symbiotic stars - the long period, interacting binary systems - composed of red giant donor and a hot, compact companion is important for our understanding of binary stellar evolution in systems where mass loss or transfer take place involving rgb/agb stars. the elemental abundances of symbiotic giants can... | chemical abundance analysis of the symbiotic red giants |
one of the important issues regarding the final evolution of stars is the impact of binarity. a rich zoo of peculiar, evolved objects are born from the interaction between the loosely bound envelope of a giant, and the gravitational pull of a companion. however, binary interactions are not understood from first princip... | constraining roche-lobe overflow models using the hot-subdwarf wide binary population |
icarus is a stellar binary light curve synthesis tool that generates a star, given some basic binary parameters, by solving the gravitational potential equation, creating a discretized stellar grid, and populating the stellar grid with physical parameters, including temperature and surface gravity. icarus also evaluate... | icarus: stellar binary light curve synthesis tool |
deriving a simple, analytic galaxy star formation history (sfh) using observational data is a complex task without the proper tool to hand. we therefore present snitch, an open source code written in python, developed to quickly (2 min) infer the parameters describing an analytic sfh model from the emission and absorpt... | snitch: seeking a simple, informative star formation history inference tool |
polaris is the nearest cepheid to us and as such holds a special place in our understanding of cepheids in general and the leavitt law. in the past couple of decades, we have learned many new things about the star as a cepheid and as the primary component of a multiple star system. as such, we are more precisely measur... | the curious case of the north star: the continuing tension between evolution models and measurements of polaris |
for decades, a subset of carbon-rich wr (wc) stars have been known to actively form dust despite their extreme environments. although these systems can produce copious amounts of dust, they have been commonly overlooked as significant sources of dust in the ism of galaxies in the local and early universe due to the per... | revisiting and resolving carbon-rich wof-rayet dust factories |
many observations supply only photometry data with large uncertainties. the study of star clusters based on such data is important for astrophysical studies, although photometric uncertainty affects the accuracy of results. in order to estimate the parameter uncertainties that are caused by photometric errors, this wor... | relation between photometric and parameter errors of star clusters |
it is well established that stellar metallicity has a significant impact on the determination of the ages of different galactic stellar populations when main sequence evolutionary tracks are used. here we study the role that metallicity plays on the age estimation for the galactic disk when the white dwarf luminosity f... | a study of the effects of metallicity on the population of galactic disk white dwarfs |
studying the unresolved stellar content of galaxies generally involves disentangling the various components contributing to the spectral energy distribution (sed), and fitting a combination of simple stellar populations (ssps) to derive information about age, metallicity, and star formation history. in the near-infrare... | models constraints from observations of active galaxies |
the asymptotic giant branch (agb) represents the phase of stellar evolution where stars become their brightest and reddest. as such, understanding stellar lifetimes and luminosities during this evolutionary phase is crucial to accurately interpret red and infrared light from galaxies using population synthesis models. ... | a direct measurement of lifetimes and stellar luminosities on the agb |
smc 3 is one of the most interesting symbiotic stars. this binary contains a bright k-type giant transferring mass to a massive white dwarf comanion, which makes it is a very promising sn ia candidate. we discuss the evolutionary status of the system using results of population synthesis code. | smc3 as a test to the binary evolution |
in this talk, i will introduce the yunnan model of evolutionary population synthesis, in which binary interactions are considered. i will review how hot objects, such as soft x-ray sources, hot subdwarf stars, blue stragglers, which radiate at short wavelengths, can be produced via binary interactions. i will then revi... | yunnan model: an eps model with binary interactions |
we propose nirspec mos spectroscopy of three massive quiescent galaxies at 3< z< 5. we have confirmed their quiescent nature and redshifts via the detection of balmer absorption lines in deep keck/mosfire spectroscopy. our robust sample selection and analysis reveals that two them are uncomfortably massive (log m... | is there evidence of alpha-enhancement in massive quiescent galaxies at z > 3? |
we study the roles of cluster dynamics and massive binary evolution in producing stellar-mass binary black hole (bbh) mergers over the cosmic time. dynamical bbh mergers are obtained from long-term direct n-body evolutionary models of ~10^4m_sun young massive clusters (ymc) evolving into open clusters. fast evolutionar... | binary black hole merger rate from young massive clusters, open clusters, and isolated binaries |
we describe our project to study galaxies hosting type ia supernova (sn ia) at different redshifts. we present optical spectroscopy of 6 galaxies at redshift $z \sim 0.45$ observed with gran telescopio de canarias. they are joined to a set of sn ia host galaxies at intermediate-high redshift, taken from sdss and cosmos... | stellar populations in type ia supernova host galaxies at intermediate-high redshift: star formation and metallicity enrichment histories |
after the second data release of gaia, the number of new globular cluster candidates has increased importantly. however, most of them need to be properly characterised, both spectroscopically and photometrically, by means of radial velocities, metallicities, and deeper photometric observations. our goal is to provide a... | the treasure behind the haystack: muse analysis of five recently discovered globular clusters |
the gaia-eso survey (ges) is a large public spectroscopic survey which acquired spectra for more than 100000 stars across all major components of the milky way. in addition to atmospheric parameters and stellar abundances that have been derived in previous papers of this series, the ges spectra allow us to detect spect... | the gaia-eso survey: new spectroscopic binaries in the milky way |
wolf-rayet (wr) stars represent the ultimate phase of evolution for the most massive stars in the universe. hot and luminous - they drive dense outflows, giving rise to rich emission-line spectra featuring nitrogen, carbon, and/or oxygen, as deeper layers of nuclear-processed material are revealed. this stripped nature... | physical properties of wolf-rayet stars at infra-red wavelengths |
x-ray binaries are a class of binary systems, in which the accretor is a compact star (i.e., black hole, neutron star, or white dwarf). they are one of the most important objects in the universe, which can be used to study not only binary evolution but also accretion disks and compact stars. statistical investigations ... | formation and evolution of x-ray binaries |
we present a spatially resolved stellar population analysis of 61 jellyfish galaxies and 47 control galaxies observed with eso/muse attempting to understand the general trends of the stellar populations as a function of the stripping intensity and mass. this is the public sample from the gasp programme, with 0.01 < ... | spatially resolved self-consistent spectral modelling of jellyfish galaxies from muse with fado: trends with mass and stripping intensity |
context. we study the relation between the known binary fraction and spectral absorption feature index to judge whether (and potentially which) spectral absorption feature indices are suitable for determining the binary fraction.aims: the determination of the binary fraction is important in studies of binary star forma... | relation between spectral indices and binary fractions in globular clusters |
in 2013 a dearth of close-in planets around fast-rotating host stars was found using statistical tests on kepler data. the addition of more kepler and transiting exoplanet survey satellite (tess) systems in 2022 filled this region of the diagram of stellar rotation period (prot) versus the planet orbital period (porb).... | stellar spectral-type (mass) dependence of the dearth of close-in planets around fast-rotating stars. architecture of kepler confirmed single-exoplanet systems compared to star-planet evolution models |
in this talk, i describe the tools used to analyze high-resolution integrated light (il) spectra in moog. these tools require input models of the underlying stellar populations, which can be generated with photometry or with theoretical isochrones. abundances can be determined from equivalent widths or spectrum synthes... | high-resolution integrated light spectroscopy of extragalactic globular clusters with moog |
we present a framework for modeling the contribution from ultra-luminous x-ray sources (ulxs) to the nebular emission from star-forming regions. we develop a physical model for the intrinsic ulx spectral energy distribution (sed) assuming supercritical accretion onto a stellar mass compact object, as well as a methodol... | nebular emission from "simple x-ray populations": the impact of ultra-luminous x-ray sources on ir-to-optical emission line diagnostics |
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