A5007950034- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- History and Developments in Astronomy
- Galaxies: Formation, Evolution, Phenomena
- Adaptive optics and wavefront sensing
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
Radboud University Nijmegen
2022
We have employed a novel way to measure the distance NGC1052-DF2, using internal stellar velocity dispersions (σ) of its globular clusters (GCs). obtained deep (15.1h), R=18,200, calcium triplet integrated-light spectra for 10 GCs in NGC1052-DF2 FLAMES GIRAFFE on VLT. For five GCs, we measured σ values, along with precision velocities whole sample. also present new photometric analysis based 40 orbits archival Hubble Space Telescope imaging 16 spectroscopically confirmed GCs. Assuming that...
The ultra-diffuse galaxy (UDG) NGC,1052-DF2 has captured the interest of astronomers ever since low velocity dispersion measured from ten globular clusters (GCs) suggested a dark matter fraction. Also, its GC system was found to be unusually bright, with luminosity function peak at least one magnitude brighter than expected for distance 20 Mpc. In this work we present an updated view NGC,1052-DF2. We analysed archival MUSE data confirm membership four additional GCs based on their radial...
Context. The chemical composition of globular clusters (GCs) across the Local Group provides information on abundance trends. Studying GCs in isolated systems particular us with important initial conditions plausibly unperturbed by mergers and tidal forces from large spirals. Aims. We present a detailed analysis Sextans A GC-1. host galaxy, A, is low-surface-brightness dwarf irregular galaxy located edge Group. derive dynamical mass GC together mass-to-light ratio abundances α , Fe-peak,...
The leading method for the determination of relevant stellar population parameters unresolved extragalactic Globular Clusters is through study their integrated spectroscopy, where Balmer line-strength indices are considered to be age sensitive. Previously, a splitting in highly optimised spectral index H$\beta_o$ was observed sample Galactic globular clusters at all metallicities resulting an apparent "upper branch" and "lower - [MgFe] diagram. This suggested caused by presence hot Blue...
We present a detailed chemical abundance analysis of the young massive cluster (YMC) NGC 1569-B. The host galaxy, NGC~1569, is dwarf irregular starburst galaxy at distance 3.36$\pm$0.20 Mpc. determined ratios from an optical integrated-light spectrum 1569-B, obtained with HIRES echelle spectrograph on Keck I telescope. considered different red-to-blue supergiant ratios, namely: ratio theoretical isochrone, resolved colour-magnitude diagram YMC, and that minimises $\chi^2$ when comparing our...