30 citations · 85 across the 14 of their papers we have counts for
15 papers
Exploring the ultrahot Neptune LTT 9779 b with CRIRES+. Non-detection of helium transmission spectra and detection of HO on the dayside
S. Liu, F. Yan, L. Nortmann +15
Ultrahot Neptunes reside in the most extreme irradiation regime of the hot Neptune desert and remain challenging targets for atmospheric characterization because of their low plane…
51 Peg b revisited with VLT/CRIRES+. Constraints on atmospheric thermal structure, chemical composition, and an alternative orbital solution
D. Cont, L. Nortmann, F. Lesjak +18
So far, the atmospheres of non-transiting exoplanets remain poorly explored, and the potential of high-resolution spectroscopy for determining key planetary parameters beyond their…
Cloudy with a chance of metals: Indications of CO in the atmosphere of GJ 1214 b from high-resolution K-band spectroscopy
L. Nortmann, D. Cont, F. Lesjak +13
Sub-Neptune exoplanets frequently exhibit muted transmission spectra, with GJ 1214 b being the most prominent example. Following years of intense observing campaigns yielding featu…
Mass determination of the ultra-short-period planet LHS 3844 b. First K-band radial velocity measurements with CRIRES+
E. Nagel, J. Köhler, M. Zechmeister +21
We present the first planet mass measurement obtained with CRIRES+ radial velocity (RV) observations using the K-band gas cell. Our target, LHS 3844 b (TOI-136), is a transiting su…
viper: High-precision radial velocities from the optical to the infrared (Reaching 3 m/s in the K band of CRIRES+ with telluric modelling)
J. Köhler, M. Zechmeister, A. Hatzes +18
In recent years, a number of new instruments and data reduction pipelines have been developed to obtain high-precision radial velocities (RVs). In particular in the optical, consid…
Abundance analysis of benchmark M dwarfs
T. Olander, U. Heiter, N. Piskunov +2
Abundances of M dwarfs, being the most numerous stellar type in the Galaxy, can enhance our understanding of planet formation processes. They can also be used to study the chemical…
Retrieving day- and nightside atmospheric properties of the ultra-hot Jupiter TOI-2109b. Detection of Fe and CO emission lines and evidence for inefficient heat transport
D. Cont, L. Nortmann, F. Lesjak +32
The ultra-hot Jupiter (UHJ) TOI-2109b marks the lower edge of the equilibrium temperature gap between 3500 K and 4500 K, an unexplored thermal regime that separates KELT-9b, the ho…
Comparative study of small-scale magnetic fields on Boo A using optical and near-infrared spectroscopy
A. Hahlin, O. Kochukhov, P. Chaturvedi +12
Magnetic field investigations of Sun-like stars, using Zeeman splitting of non-polarised spectra, in the optical and H-band have found significantly different magnetic field streng…
Retrieving wind properties from the ultra-hot dayside of WASP-189b with CRIRES
F. Lesjak, L. Nortmann, D. Cont +12
The extreme temperature gradients from day- to nightside in the atmospheres of hot Jupiters generate fast winds in the form of equatorial jets or day-to-night flows. Observations o…
Exploring the ultra-hot Jupiter WASP-178b. Constraints on atmospheric chemistry and dynamics from a joint retrieval of VLT/CRIRES and space photometric data
D. Cont, L. Nortmann, F. Yan +14
Despite recent progress in the spectroscopic characterization of individual exoplanets, the atmospheres of key ultra-hot Jupiters (UHJs) still lack comprehensive investigations. Th…
Are the surface abundance structures stable in rapidly rotating Ap star 56 Ari?
I. Potravnov, N. Piskunov, T. Ryabchikova
The surface magnetic and abundance inhomogeneities in chemically peculiar Ap/Bp stars are coupled and responsible for their rotationally modulated variability. Within the framework…
A conclusive non-detection of magnetic field in the Am star o Peg with high-precision near-infrared spectroscopy
O. Kochukhov, A. M. Amarsi, A. Lavail +10
The A-type metallic-line (Am) stars are typically considered to be non-magnetic or possessing very weak sub-G magnetic fields. This view has been repeatedly challenged in the liter…
CRIRES transmission spectroscopy of WASP-127b. Detection of the resolved signatures of a supersonic equatorial jet and cool poles in a hot planet
L. Nortmann, F. Lesjak, F. Yan +14
General circulation models of gas giant exoplanets predict equatorial jets that drive inhomogeneities in the atmospheric physical parameters across the planetary surface. We studie…
Doppler imaging of a southern ApSi star HD 152564
I. Potravnov, T. Ryabchikova, N. Piskunov +2
We present the results of the spectroscopic study of a chemically peculiar star HD 152564. Using medium-resolution () observations obtained with the HRS spectrograph mount…
Rotation, magnetism, and metallicity of M dwarf systems
D. Shulyak, A. Seifahrt, A. Reiners +2
Close M-dwarf binaries and higher multiples allow the investigation of rotational evolution and mean magnetic flux unbiased from scatter in inclination angle and age since the orie…