papers

Publications (9)

astro-ph.GA2009

The isolated neutron star RBS1774 revisited. Revised XMM-Newton X-ray parameters and an optical counterpart from deep LBT-observations

A. Schwope, T. Erben, J. Kohnert +12

We report optical B-band observations with the Large Binocular Telescope LBT of the isolated neutron star RBS1774. The stacked image with total exposure 2.5h reveals a candidate op…

astro-ph.IM2016

EELT-HIRES the high-resolution spectrograph for the E-ELT

A. Marconi, P. Di Marcantonio, V. D'Odorico +70

The first generation of E-ELT instruments will include an optical-infrared High Resolution Spectrograph, conventionally indicated as EELT-HIRES, which will be capable of providing…

astro-ph2007

GREGOR: the New German Solar Telescope

H. Balthasar, O. von der Lühe, F. Kneer +17

GREGOR is a new open solar telescope with an aperture of 1.5m. It replaces the former 45-cm Gregory Coude telescope on the Canary island Tenerife. The optical concept is that of a…

astro-ph.SR2016

Magnetic fields of opposite polarity in sunspot penumbrae

M. Franz, M. Collados, C. Bethge +25

Context. A significant part of the penumbral magnetic field returns below the surface in the very deep photosphere. For lines in the visible, a large portion of this return field c…

astro-ph.SR2016

Probing deep photospheric layers of the quiet Sun with high magnetic sensitivity

A. Lagg, S. K. Solanki, H. -P. Doerr +31

Context. Investigations of the magnetism of the quiet Sun are hindered by extremely weak polarization signals in Fraunhofer spectral lines. Photon noise, straylight, and the system…

astro-ph.CO2011

Calibrating the Cepheid Period-Luminosity relation from the infrared surface brightness technique I. The p-factor, the Milky Way relations, and a universal K-band relation

J. Storm, W. Gieren, P. Fouque +6

We determine Period-Luminosity relations for Milky Way Cepheids in the optical and near-IR bands. These relations can be used directly as reference for extra-galactic distance dete…

astro-ph.SR2010

Modeling the Subsurface Structure of Sunspots

H. Moradi, C. Baldner, A. C. Birch +19

While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspo…

astro-ph.SR2016

FK Comae Berenices, King of Spin: The COCOA-PUFS Project

Thomas R. Ayres, V. Kashyap, S. Saar +8

COCOA-PUFS is an energy-diverse, time-domain study of the ultra-fast spinning, heavily spotted, yellow giant FK Com (HD117555; G4 III). This single star is thought to be a recent b…

astro-ph.IM2013

A Community Science Case for E-ELT HIRES

R. Maiolino, M. Haehnelt, M. T. Murphy +57

Building on the experience of the high-resolution community with the suite of VLT high-resolution spectrographs, which has been tremendously successful, we outline here the (scienc…