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MOCCA-survey data base: extra galactic globular clusters – II. Milky Way and Andromeda

A comprehensive study of the co-evolution of globular cluster systems (GCS) in galaxies requires the ability to model both the large-scale dynamics (0.01–10 kpc) regulating their orbital evolution, and the small-scale dynamics (sub-pc – au) regulating the internal dynamics of each globular cluster (GC). In this work, we present a novel method that combine semi-analytic models of GCS with fully sel

Exploring compact binary populations with the Einstein Telescope

The Einstein Telescope (ET), a wide-band, future third generation gravitational wave detector, is expected to have detection rates of ∼105 − 106 binary black hole (BBH) detections and ∼7 × 104 binary neutron star (BNS) detections in one year. The coalescence of compact binaries with a total mass of 20–100 M⊙, typical of BH-BH or BH-NS binaries, will be visible up to redshift z ≈ 20 and even higher

Self-consistent modelling of the Milky Way's nuclear stellar disc

The nuclear stellar disc (NSD) is a flattened high-density stellar structure that dominates the gravitational field of the Milky Way at Galactocentric radius $30\, {\rm pc}\lesssim R\lesssim 300\, {\rm pc}$. We construct axisymmetric self-consistent equilibrium dynamical models of the NSD in which the distribution function is an analytic function of the action variables. We fit the models to the n

Accurately Measured Wavelengths of Zn I and Zn II Lines of Astrophysical Interest

Zinc is an element of importance in many research fields within astronomy and astrophysics, from cosmology to stellar atmosphere dynamics. With the aim of improving three decades old measurements of zinc lines of astrophysical interest, emission spectra of Zn I and Zn II have been recorded using a Fourier Transform Spectrometer with a hollow cathode light source. Revised energies for previously kn

Stellar feedback in M83 as observed with MUSE : I. Overview, an unprecedented view of the stellar and gas kinematics and evidence of outflowing gas

Context. Young massive stars inject energy and momentum into the surrounding gas, creating a multi-phase interstellar medium (ISM) and regulating further star formation. The main challenge of studying stellar feedback proves to be the variety of scales spanned by this phenomenon, ranging from the immediate surrounding of the stars (Ha II regions, 10s pc scales) to galactic-wide kiloparsec scales.

THA 15-31 : Discovery with VLT/X-shooter and Swift /UVOT of a new symbiotic star of the accreting-only variety

We report the discovery and characterization of a new symbiotic star of the accreting-only variety, which we observed in the optical/near-infrared (NIR) with VLT/X-shooter and in the X-rays/ultraviolet with Swift/UVOT+XRT. The new symbiotic star, THA 15-31, was previously described as a pre-main sequence star belonging to the Lupus 3 association. Our observations, ancillary data, and Gaia EDR3 par

The Gaia -ESO Survey : The analysis of the hot-star spectra

Context. The Gaia-ESO Survey (GES) is a large public spectroscopic survey that has collected, over a period of six years, spectra of ~105 stars. This survey provides not only the reduced spectra, but also the stellar parameters and abundances resulting from the analysis of the spectra. Aims. The GES dataflow is organised in 19 working groups. Working group 13 (WG13) is responsible for the spectral

The nuclear stellar disc of the Milky Way : A dynamically cool and metal-rich component possibly formed from the central molecular zone

Context. The nuclear stellar disc (NSD) is, together with the nuclear star cluster (NSC) and the central massive black hole, one of the main components in the central parts of our Milky Way. However, until recently, only a few studies of the stellar content of the NSD have been obtained owing to extreme extinction and stellar crowding. Aims. We study the kinematics and global metallicities of the

The deepest X-ray view of high-redshift galaxies : Constraints on low-rate black hole accretion

We exploit the 7 Ms Chandra observations in the Chandra Deep Field-South (CDF-S), the deepest X-ray survey to date, coupled with CANDELS/GOODS-S data, to measure the total X-ray emission arising from 2076 galaxies at 3.5 ≤ z < 6.5. This aim is achieved by stacking the Chandra data at the positions of optically selected galaxies, reaching effective exposure times of ≥109s.We detect significant (>3.

THE CHANDRA COSMOS LEGACY SURVEY : OPTICAL/IR IDENTIFICATIONS

We present the catalog of optical and infrared counterparts of the Chandra COSMOS-Legacy Survey, a 4.6 Ms Chandra program on the 2.2 deg2 of the COSMOS field, combination of 56 new overlapping observations obtained in Cycle 14 with the previous C-COSMOS survey. In this Paper we report the i, K, and 3.6 μm identifications of the 2273 X-ray point sources detected in the new Cycle 14 observations. We

Massive star cluster formation and evolution in tidal dwarf galaxies

Context. The formation of globular clusters remains an open debate. Dwarf starburst galaxies are efficient at forming young massive clusters with similar masses as globular clusters and may hold the key to understanding their formation. Aims. We study star cluster formation in a tidal debris, including the vicinity of three tidal dwarf galaxies, in a massive gas-dominated collisional ring around N

Massive star cluster formation and evolution in tidal dwarf galaxies

The formation of globular clusters remains an open debate. Dwarf starburst galaxies are efficient at forming young massiveclusters with similar masses as globular clusters and may hold the key to understanding their formation.Aims.We study star cluster formation in a tidal debris - including the vicinity of three tidal dwarf galaxies - in a massive gas dominatedcollisional ring around NGC 5291. Th

The Gaia-ESO Survey : Oxygen Abundance in the Galactic Thin and Thick Disks

We analyze the oxygen abundances of a stellar sample representative of the two major Galactic populations: the thin and thick disks. The aim is to investigate the differences between members of the Galactic disks and contribute to the understanding of the origin of oxygen chemical enrichment in the Galaxy. The analysis is based on the [O i] = 6300.30 Å oxygen line in high-resolution spectra (R ∼ 5

APOGEE Chemical Abundance Patterns of the Massive Milky Way Satellites

The SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey has obtained high-resolution spectra for thousands of red giant stars distributed among the massive satellite galaxies of the Milky Way (MW): the Large and Small Magellanic Clouds (LMC/SMC), the Sagittarius Dwarf Galaxy (Sgr), Fornax (Fnx), and the now fully disrupted Gaia Sausage/Enceladus (GSE) system. We present

The GALAH Survey : chemical tagging and chrono-chemodynamics of accreted halo stars with GALAH+ DR3 and Gaia eDR3

Since the advent of Gaia astrometry, it is possible to identify massive accreted systems within the Galaxy through their unique dynamical signatures. One such system, Gaia-Sausage-Enceladus (GSE), appears to be an early 'building block' given its virial mass >1010M⊙ at infall (z ~ 1-3). In order to separate the progenitor population from the background stars, we investigate its chemical properties

The Seventeenth Data Release of the Sloan Digital Sky Surveys : Complete Release of MaNGA, MaStar and APOGEE-2 Data

This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library (MaStar) accompanies

The GALAH Survey: Chemical Clocks

We present the first large-scale study that demonstrates how ages can be determined for large samples of stars through Galactic chemical evolution. Previous studies found that the elemental abundances of a star correlate directly with its age and metallicity. Using this knowledge, we derive ages for 214 577 stars in GALAH DR3 using only overall metallicities and chemical abundances. Stellar ages a

An old, metal-rich accreted stellar component in the Milky Way stellar disk

We study the possibility that the Milky Ways' cool stellar disk includes mergers with ancient stars. Galaxies are understood to form in a hierarchical manner, where smaller (proto-)galaxies merge into larger ones. Stars in galaxies, like the Milky Way, contain in their motions and elemental abundance tracers of past events and can be used to disentangle merger remnants from stars that formed in th