activity
20222026
most citedAtmospheric characterization of the ultra-hot Jupiter WASP-33b: Detection of Ti and V emission lines and retrieval of a broadened line profile

42 citations · 195 across the 19 of their papers we have counts for

collaborators

20 papers

astro-ph.EP2026

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…

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.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.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.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.EP2025★ 1 cited

Revisiting the atmosphere of HAT-P-70b with CARMENES high-resolution transmission spectroscopy

Tianjun Gan, Jaume Orell-Miquel, Fei Yan +19

Owing to hot and inflated envelopes that facilitate atmospheric studies, ultra-hot Jupiters (UHJs) have attracted much attention. Significant progress has been achieved, from enlar…

astro-ph.EP2025★ 5 cited

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★ 3 cited

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.EP2025★ 1 cited

VLT/CRIRES+ observations of warm Neptune WASP-107 b: Challenges in detecting molecules with ground-based transmission spectroscopy of cooler and cloudy exoplanets

Linn Boldt-Christmas, Adam D. Rains, Nikolai Piskunov +15

Atmospheres of transiting exoplanets can be studied spectroscopically using space-based or ground-based observations. Each has its own strengths and weaknesses, so there are benefi…

astro-ph.EP2025★ 8 cited

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.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★ 1 cited

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…

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.EP2024★ 33 cited

The MOPYS project: A survey of 70 planets in search of extended He I and H atmospheres. No evidence of enhanced evaporation in young planets

J. Orell-Miquel, F. Murgas, E. Pallé +30

During the first Gyr of their life, exoplanet atmospheres suffer from different atmospheric escape phenomena that can strongly affect the shape and morphology of the exoplanet itse…

astro-ph.EP2024★ 30 cited

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.EP2024★ 1 cited

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.EP2023★ 2 cited

Optimising spectroscopic observations of transiting exoplanets

Linn Boldt-Christmas, Fabio Lesjak, Ansgar Wehrhahn +4

When observing the atmospheres of transiting exoplanets using high-resolution spectroscopy, one aims to detect well-resolved spectral features with high signal-to-noise ratios (SNR…

astro-ph.EP2023★ 28 cited

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★ 40 cited

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.EP2022★ 42 cited

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…