A5052086040- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Geophysics and Gravity Measurements
- Astro and Planetary Science
- Scientific Research and Discoveries
- Astronomical Observations and Instrumentation
- Geomagnetism and Paleomagnetism Studies
- Online and Blended Learning
- Student Assessment and Feedback
- Education and Critical Thinking Development
- Galaxies: Formation, Evolution, Phenomena
Visby lasarett
2024
Uppsala University
2019-2022
Max Planck Society
2018
The chemo-physical parametrisation of stellar spectra is essential for understanding the nature and evolution stars Galactic populations. Gaia DR3 contains RVS data performed by General Stellar Parametriser-spectroscopy, module. Here we describe first 34 months observations. GSP-spec estimates parameters from combined single stars. main analysis workflow described here, MatisseGauguin, based on projection optimisation methods provides atmospheric parameters; individual chemical abundances N,...
We present the General Stellar Parameterizer from Photometry (GSP-Phot), which is part of astrophysical parameters inference system (Apsis). GSP-Phot designed to produce a homogeneous catalogue for hundreds millions single non-variable stars based on their astrometry, photometry, and low-resolution BP/RP spectra. These are effective temperature, surface gravity, metallicity, absolute $M_G$ magnitude, radius, distance, extinction each star. uses Bayesian forward-modelling approach...
Context. As part of the third Gaia data release, we present contributions non-stellar and classification modules from eighth coordination unit (CU8) Data Processing Analysis Consortium, which is responsible for determination source astrophysical parameters using data. This in a series three papers describing work done within CU8 this release. Aims. For each five relevant CU8, summarise their objectives, methods they employ, performance, results produce DR3. We further advise how to use these...
ABSTRACT Analyses of data from spectroscopic and astrometric surveys have led to conflicting results concerning the vertical characteristics Milky Way. Ages are often used provide clarity, but typical uncertainties >40 per cent photometry restrict validity inferences made. Using Kepler APOKASC sample for context, we explore global population trends two K2 campaign fields (3 6), which extend further vertically out Galactic plane than APOKASC. We analyse properties red giant stars...
This study is the first to investigate how an online course consisting solely of multiple-choice questions and detailed formative feedback compares format that was previously shown be highly effective. Specifically, a pure question-based learning (pQBL) version compared (QBL) which consisted same as pQBL course, but also included ordinary texts about subject. To explore QBL in terms outcomes completion time, 492 employees at Swedish Employment Agency were randomized either or IT security....
The Gaia Radial Velocity Spectrometer provides the unique opportunity of a spectroscopic analysis millions stars at medium-resolution in near-infrared. This wavelength range includes Ca II infrared triplet (IRT), which is good diagnostics magnetic activity chromosphere late-type stars. Here we present method devised for inferring stellar index together with its scientific validation. A sample well studied PMS considered to identify regime may be affected by mass accretion. position these...
The extensive stellar spectroscopic datasets that are available for studies in Galactic Archeaology thanks to, example, the Gaia-ESO Survey, now benefit from having a significant number of targets overlap with asteroseismology projects such as Kepler, K2 and CoRoT. Combining measurements spectroscopy allows us to attain greater accuracy regard parameters needed characterise populations Milky Way. aim this Survey special project is produce catalogue self-consistent by combining...
Gaia Data Release 3 will contain more than a billion sources with positions, parallaxes, and proper motions. In addition, for hundreds of millions stars, it include low-resolution blue photometer (BP) red (RP) spectra. Obtained by dispersing light prisms, these spectra have resolutions that are too low to allow us measure individual spectral lines bands. However, the combined BP/RP can be used estimate some stellar properties such as $T_{\text{eff}}$, $\log{g}$, $\left[ \text{M} / \text{H}...
Context. The Gaia -ESO Survey has taken high-quality spectra of a subset 100 000 stars observed with the spacecraft. goal for this is to derive chemical abundances these that will complement astrometric data collected by . Deriving requires stellar parameters be determined. Aims. We present pipeline deriving from FLAMES-UVES spectrograph in its standard fibre-fed mode centred on 580 nm, as used Survey. quantify performance terms systematic offsets and scatter. In doing so, we general method...
We attempt to constrain the efficiency of additional transport or mixing processes that reduce effect atomic diffusion in stellar atmospheres. apply spectral synthesis methods spectra observed with GIRAFFE spectrograph on VLT estimate abundances Mg, Ti, Fe, and Ba stars metal-poor globular cluster M30. To we fit trends predicted by evolution models assuming different efficiencies processes. The fitting procedure attempts take into account effects parameter-dependent systematic errors derived...