papers

Publications (26)

astro-ph.EP2026

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…

astro-ph.EP2025

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…

astro-ph.EP2026

Phase-curve approach to study atmospheric flows in hot Jupiters

D. Shulyak, W. Dietrich, V. Parmentier +5

Short-orbit gaseous exoplanets are the best targets to study atmospheric dynamics. A time series of emission observations collected at various photometric filters (phase curves) pr…

astro-ph.EP2022

Detection of CO emission lines in the dayside atmospheres of WASP-33b and WASP-189b with GIANO

F. Yan, E. Pallé, A. Reiners +8

Ultra-hot Jupiters (UHJs) are expected to possess temperature inversion layers in their dayside atmospheres. Recent thermal emission observations have discovered several atomic and…

astro-ph.EP2022

Detection of iron emission lines and a temperature inversion on the dayside of the ultra-hot Jupiter KELT-20b

F. Yan, A. Reiners, E. Pallé +25

Ultra-hot Jupiters (UHJs) are gas giants with very high equilibrium temperatures. In recent years, multiple chemical species, including various atoms and ions, have been discovered…

astro-ph.EP2022

Atmospheric characterization of the ultra-hot Jupiter WASP-33b: Detection of Ti and V emission lines and retrieval of a broadened line profile

D. Cont, F. Yan, A. Reiners +17

Ultra-hot Jupiters are highly irradiated gas giant exoplanets on close-in orbits around their host stars. We analyzed high-resolution spectra from CARMENES, HARPS-N, and ESPaDOnS t…

astro-ph.EP2024

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…

astro-ph.EP2025

Elemental abundance pattern and temperature inversion on the dayside of HAT-P-70b observed with CARMENES and PEPSI

B. Guo, F. Yan, Th. Henning +25

Ground-based high-resolution spectroscopy has identified various chemical species in the atmospheres of ultra-hot Jupiters, including neutral and ionized metals, providing key insi…

astro-ph.EP2021

Silicon in the dayside atmospheres of two ultra-hot Jupiters

D. Cont, F. Yan, A. Reiners +22

Atmospheres of highly irradiated gas giant planets host a large variety of atomic and ionic species. Here we observe the thermal emission spectra of the two ultra-hot Jupiters WASP…

astro-ph.EP2026

Spinning out of focus: The challenge of rotational line broadening in exoplanet reflection spectroscopy

T. O. Winterhalder, K. Molaverdikhani, D. Cont +17

Detecting light reflected off the dayside of an exoplanet in high-resolution spectroscopic data has proved to be a notoriously difficult endeavour. Despite several attempts, the fa…

astro-ph.EP2023

CRIRES+ detection of CO emissions lines and temperature inversions on the dayside of WASP-18b and WASP-76b

F. Yan, L. Nortmann, A. Reiners +21

The dayside atmospheres of ultra-hot Jupiters (UHJs) are predicted to possess temperature inversion layers with extremely high temperatures at high altitudes. We observed the daysi…

astro-ph.EP2026

Cold and eccentric: a high-spectral resolution view of 51 Eri b with VLT/HiRISE

A. Denis, A. Vigan, G. Chauvin +35

Discovered almost 10 years ago, the giant planet 51 Eridani b is one of the least separated (0.2 arcsec) and faintest (J = 19.74 mag) directly imaged exoplanets known to date. Its…

astro-ph.EP2024

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…

astro-ph.EP2024

The elusive atmosphere of WASP-12 b / High-resolution transmission spectroscopy with CARMENES

S. Czesla, M. Lampón, D. Cont +19

To date, the hot Jupiter WASP-12 b has been the only planet with confirmed orbital decay. The late F-type host star has been hypothesized to be surrounded by a large structure of c…

astro-ph.EP2026

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…

astro-ph.EP2020

Detection of the hydrogen Balmer lines in the ultra-hot Jupiter WASP-33b

F. Yan, A. Wyttenbach, N. Casasayas-Barris +24

Ultra-hot Jupiters (UHJs) are highly irradiated giant exoplanets with extremely high day-side temperatures, which lead to thermal dissociation of most of the molecular species. It…

astro-ph.EP2025

Tighter constraints on the atmosphere of GJ 436 b from combined high-resolution CARMENES and CRIRES observations

A. Peláez-Torres, A. Sánchez-López, L. Nortmann +23

We aim to study the atmospheric properties of the warm Neptune GJ 436 b by combining a set of five transit events observed with the CARMENES spectrograph with one transit from CRIR…

astro-ph.EP2025

Characterization of AF Lep b at high spectral resolution with VLT/HiRISE

A. Denis, A. Vigan, J. Costes +41

Since the recent discovery of the directly imaged super-Jovian planet AF Lep b, several studies have been conducted to characterize its atmosphere and constrain its orbital paramet…

astro-ph.EP2023

Retrieval of the dayside atmosphere of WASP-43b with CRIRES+

F. Lesjak, L. Nortmann, F. Yan +15

Accurately estimating the C/O ratio of hot Jupiter atmospheres is a promising pathway towards understanding planet formation and migration, as well as the formation of clouds and t…

astro-ph.EP2023

The CARMENES search for exoplanets around M dwarfs. Guaranteed time observations Data Release 1 (2016-2020)

I. Ribas, A. Reiners, M. Zechmeister +102

The CARMENES instrument was conceived to deliver high-accuracy radial velocity (RV) measurements with long-term stability to search for temperate rocky planets around a sample of n…

astro-ph.EP2025

Upper limits on atmospheric abundances of KELT-11b and WASP-69b from a retrieval approach

F. Lesjak, L. Nortmann, D. Cont +18

WASP-69b and KELT-11b are two low-density hot Jupiters, which are expected to show strong atmospheric features in their transmission spectra. Such features offer valuable insights…

astro-ph.EP2024

Detection of Fe and Ti on the dayside of the ultrahot Jupiter MASCARA-1b with CARMENES

B. Guo, F. Yan, L. Nortmann +20

Ultrahot Jupiters are a type of gaseous exoplanet that orbit extremely close to their host star, resulting in significantly high equilibrium temperatures. In recent years, high-res…

astro-ph.EP2021

Detection of Fe and evidence for TiO in the dayside emission spectrum of WASP-33b

D. Cont, F. Yan, A. Reiners +23

Theoretical studies predict the presence of thermal inversions in the atmosphere of highly irradiated gas giant planets. Recent observations have identified these inversion layers.…

astro-ph.EP2024

Small but mighty: High-resolution spectroscopy of ultra-hot Jupiter atmospheres with compact telescopes. KELT-9 b's transmission spectrum with Wendelstein's FOCES Spectrograph

N. W. Borsato, H. J. Hoeijmakers, D. Cont +9

When observing transmission spectra produced by atmospheres of ultra-hot Jupiters, large telescopes are typically the instrument of choice due to the very weak signal of the planet…

astro-ph.EP2026

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…

astro-ph.EP2024

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…