1.7k citations · 7.7k across the 76 of their papers we have counts for
23 papers · 1 filter
Magnetism, rotation, and nonthermal emission in cool stars -- Average magnetic field measurements in 292 M dwarfs
A. Reiners, D. Shulyak, P. J. Käpylä +16
Stellar dynamos generate magnetic fields that are of fundamental importance to the variability and evolution of Sun-like and low-mass stars, and for the development of their planet…
The CARMENES search for exoplanets around M dwarfs. Mapping stellar activity indicators across the M dwarf domain
M. Lafarga, I. Ribas, A. Reiners +19
Stellar activity poses one of the main obstacles for the detection and characterisation of small exoplanets around cool stars, as it can induce radial velocity (RV) signals that ca…
Simultaneous photometric and CARMENES spectroscopic monitoring of fast-rotating M dwarf GJ 3270. Discovery of a post-flare corotating feature
E. N. Johnson, S. Czesla, B. Fuhrmeister +33
Context: Active M dwarfs frequently exhibit large flares, which can pose an existential threat to the habitability of any planet in orbit in addition to making said planets more di…
The CARMENES search for exoplanets around M dwarfs: Rubidium abundances in nearby cool stars
C. Abia, H. M. Tabernero, S. A. Korotin +25
In this study, abundances of the neutron-capture elements Rb, Sr, and Zr are derived, for the first time, in a sample of nearby M dwarfs. We focus on stars in the metallicity range…
The CARMENES search for exoplanets around M dwarfs -- A deep learning approach to determine fundamental parameters of target stars
V. M. Passegger, A. Bello-García, J. Ordieres-Meré +26
Existing and upcoming instrumentation is collecting large amounts of astrophysical data, which require efficient and fast analysis techniques. We present a deep neural network arch…
The CARMENES search for exoplanets around M dwarfs: Convective shift and starspot constraints from chromatic radial velocities
D. Baroch, J. C. Morales, I. Ribas +26
Context. Variability caused by stellar activity represents a challenge to the discovery and characterization of terrestrial exoplanets and complicates the interpretation of atmosph…
The CARMENES search for exoplanets around M dwarfs. Variability of the He I line at 10830 Å
B. Fuhrmeister, S. Czesla, L. Hildebrandt +23
The He I infrared (IR) triplet at 10830 Åis known as an activity indicator in solar-type stars and has become a primary diagnostic in exoplanetary transmission spectroscopy. He I l…
The CARMENES search for exoplanets around M dwarfs. The He I infrared triplet lines in PHOENIX models of M2-3 V stars
D. Hintz, B. Fuhrmeister, S. Czesla +25
The He I infrared (IR) line at a vacuum wavelength of 10833 A is a diagnostic for the investigation of atmospheres of stars and planets orbiting them. For the first time, we study…
The CARMENES search for exoplanets around M dwarfs. The He I triplet at 10830 across the M dwarf sequence
B. Fuhrmeister, S. Czesla, L. Hildebrandt +24
The He I infrared (IR) triplet at 10830 AA is an important activity indicator for the Sun and in solar-type stars, however, it has rarely been studied in relation to M dwarfs to da…
The CARMENES search for exoplanets around M dwarfs -- Photospheric parameters of target stars from high-resolution spectroscopy. II. Simultaneous multiwavelength range modeling of activity insensitive lines
V. M. Passegger, A. Schweitzer, D. Shulyak +25
We present precise photospheric parameters of 282 M dwarfs determined from fitting the most recent version of PHOENIX models to high-resolution CARMENES spectra in the visible (0.5…
Magnetic fields in M dwarfs from the CARMENES survey
D. Shulyak, A. Reiners, E. Nagel +20
M dwarfs are known to generate the strongest magnetic fields among main-sequence stars with convective envelopes, but the link between the magnetic fields and underlying dynamo mec…
The CARMENES search for exoplanets around M dwarfs. Chromospheric modeling of M2-3 V stars with PHOENIX
D. Hintz, B. Fuhrmeister, S. Czesla +26
Chromospheric modeling of observed differences in stellar activity lines is imperative to fully understand the upper atmospheres of late-type stars. We present one-dimensional para…
The CARMENES search for exoplanets around M dwarfs. Activity indicators at visible and near-infrared wavelengths
P. Schöfer, S. V. Jeffers, A. Reiners +21
The CARMENES survey is searching for Earth-like planets orbiting M dwarfs using the radial velocity method. Studying the stellar activity of the target stars is important to avoid…
The CARMENES search for exoplanets around M dwarfs. Period search in H, Na I D, and Ca II IRT lines
B. Fuhrmeister, S. Czesla, J. H. M. M. Schmitt +20
We use spectra from CARMENES, the Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs, to search for periods in chro…
The CARMENES search for exoplanets around M dwarfs: Nine new double-line spectroscopic binary stars
D. Baroch, J. C. Morales, I. Ribas +27
Context. The CARMENES spectrograph is surveying ~300 M dwarf stars in search for exoplanets. Among the target stars, spectroscopic binary systems have been discovered, which can be…
The CARMENES search for exoplanets around M dwarfs: Radial-velocity variations of active stars in visual-channel spectra
L. Tal-Or, M. Zechmeister, A. Reiners +22
Previous simulations predicted the activity-induced radial-velocity (RV) variations of M dwarfs to range from cm/s to km/s, depending on various stellar and activit…
The CARMENES search for exoplanets around M dwarfs: Wing asymmetries of H, Na I D, and He I lines
B. Fuhrmeister, S. Czesla, J. H. M. M. Schmitt +13
Stellar activity is ubiquitously encountered in M dwarfs and often characterised by the H line. In the most active M dwarfs, H is found in emission, sometimes with a complex…
Detection of CO absorption in the atmosphere of the hot Jupiter HD 189733b
Florian Rodler, Martin Kürster, John R. Barnes
With time-series spectroscopic observations taken with the Near Infrared Spectrometer (NIRSPEC) at Keck II, we investigated the atmosphere of the close orbiting transiting extrasol…
A spectral differential approach to characterizing low-mass companions to late-type stars
N. M. Kostogryz, M. Kuerster, T. M. Yakobchuk +2
In this paper, we develop a spectral differential technique with which the dynamical mass of low-mass companions can be found. This method aims at discovering close companions to l…
The activity and rotation limit in the Hyades
U. Seemann, A. Reiners, A. Seifahrt +1
We conduct a study of K to M type stars to investigate the activity and the rotation limit in the Hyades. We use a sample of 40 stars in this intermediate-age cluster (~625 Myr) to…
A search for star-planet interactions in chromospheric lines
L. F. Lenz, A. Reiners, M. Kürster
Massive planets in very close orbits around their central stars can induce so-called star-planet interactions (SPI), which may be of magnetic or gravitational nature. In both cases…
Tau Boo b: Hunting for reflected starlight
F. Rodler, M. Kuerster, T. Henning
Aims. We attempt to detect starlight reflected from the hot Jupiter orbiting the main-sequence star Tau Boo, in order to determine the albedo of the planetary atmosphere, the orbit…
CARMENES: Calar Alto high-Resolution search for M dwarfs with Exo-earths with a Near-infrared Echelle Spectrograph
A. Quirrenbach, P. J. Amado, H. Mandel +55
CARMENES, Calar Alto high-Resolution search for M dwarfs with Exo-earths with a Near-infrared Echelle Spectrograph, is a study for a next-generation instrument for the 3.5m Calar A…