topics at the drs late stages stellar evolution white dwarfs hot massive stars &...

Topics at the DRS Late stages stellar evolution White dwarfs Hot massive stars & extragalactic stellar astronomy Binaries with massive companions X-ray astronomy, neutron stars, black holes & AGN

Late stages of stellar evolution

SN Iaprogenitors

Chemical composition

Kinematics,Hypervelocit

y stars

Stephan Geier

Heiko HirschUli Heber

Christian Schmitt

White dwarf rotation

Alfred Tillich

pulsations

Hot massive stars & extragalactic stellar astronomy

NLTE model

atmospheres

Galactic abundance gradients

Chemical composition

Fernanda Nieva

Markus Firnstein

Norbert PrzybillaBA

Supergiants

Florian Schiller

White dwarfs

Diffusion Magnetic fields

Klaus Unglaub

Irmela Bues

Binaries with massive components

Horst Drechsel

Light curves

Large Magellanic

cloud

Stefan Nesslinger

Neutron stars, black holes & AGNNeutron

stars, black holes &AGN

Jörn Wilms

Cygnus X-1

Manfred Hanke

Observations

Optical spectroscopy: ESO, Calar Alto, Keck UV spectroscopy: HST & FUSE X-ray: XMM, Chandra, Suzaku, RXTE γ-ray: INTEGRAL Imaging & Astrometry Future: eRosita, SIMBOL-X

Education

Lecture courses for - Physics undergraduates (1. year) - Physics graduates - student teachers - non-physics graduates (mostly computer science) Lab course (Praktikum): 60 students/year Numerics course

Plate Archive

more than 40000 plates photographic monitoring (Felderplan with Sonneberg & Potsdam) from Bamberg: 1921 – 1960 Boyden-station (South Africa): 1963-1974 more than 12000 plates plate scanning since 2003 collaboration with Tsvetkov et al. (Bulgarian Academy of Sciences)

Public Outreach

Public observations, guided tours, slide shows and public lectures: 700-2000 people/year

Collaborations

Komponenten der Galaxis

Buser

Dark matter

Very old stars

Old starsYoung &

old stars

Quantitative

Spektralanalyse

Komplexe

Modelatome:

Schwere Elemente

Model Atmosphere

Atmospheric Parameters Teff, logg, [M/H]

Input

DETAILStatistical Equilibrium

&Radiative Transference

Rij = Rij(J)

Iteration until S

i = Si-1

S= S(ni)

Occupation numbers ni for each

* f line components* Statistical Weightscol and rad

Line profiles of the atom

Output DETAILInput SURFACE

ji

ijjijji

ijiji C+Rn=C+Rn )()(

1*)( iii S+S=J

)(),(),( τPτPτT e

Voigt profile

Abundan

ce

SURFACE

Model AtomLevels:

*Excitation Potentials*Statistical Weights*Ionization States

Transitions:*Oscillator Strength

*Photoionization cross sections*Excitation and Ionization

cross sections

F

lux

Elementhäufigkeiten

Heiße Sterne: Ultravioletspektroskopie: HST

Elementhäufigkeiten:

- Unterhäufigkeiten leichter Elemente- Überhäufigkeiten schwerer Elemente

im Vergleich zur Sonne

Asteroseismologie

Nichtradiale Pulsationen

Hyper-velocity star

Definition:

- Raumgeschwindigkeit übersteigt lokale Entweichgeschwindigkeit

Stern ist nicht mehr an Galaxis gebunden

- Entweichgeschwindigkeit von der Galaxis: ca. 500km/s