371 citations · 1.2k across the 25 of their papers we have counts for
25 papers
The SRG/eROSITA All-Sky Survey DR2: Cumulative X-ray catalogues from the first three surveys and multi-wavelength counterparts in the western Galactic hemisphere
M. E. Ramos-Ceja, G. Lamer, M. Salvato +111
The eROSITA telescope array on board the Spektrum-Roentgen-Gamma (SRG) mission began its all-sky survey program in December 2019, scanning the sky at an approximately six-month cad…
The eROSITA Upper Limits: Description and access to the data
D. Tubín-Arenas, M. Krumpe, G. Lamer +13
The soft X-ray instrument eROSITA on board the Spectrum-Roentgen-Gamma (SRG) observatory has successfully completed four of the eight planned all-sky surveys, detecting almost one…
The SRG/eROSITA all-sky survey: First X-ray catalogues and data release of the western Galactic hemisphere
A. Merloni, G. Lamer, T. Liu +142
The eROSITA telescope array aboard the Spektrum Roentgen Gamma (SRG) satellite began surveying the sky in December 2019, with the aim of producing all-sky X-ray source lists and sk…
The high-energy environment of the heavy sub-Earth GJ 367 b indicates likely complete evaporation of its atmosphere
K. Poppenhaeger, L. Ketzer, N. Ilic +5
The planet GJ 367 b is a recently discovered high-density sub-Earth orbiting an M dwarf star. Its composition was modelled to be predominantly iron with a potential remainder of a…
Ground-breaking Exoplanet Science with the ANDES spectrograph at the ELT
Enric Palle, Katia Biazzo, Emeline Bolmont +56
In the past decade the study of exoplanet atmospheres at high-spectral resolution, via transmission/emission spectroscopy and cross-correlation techniques for atomic/molecular mapp…
Three young planets around the K-dwarf K2-198: High-energy environment, evaporation history and expected future
Laura Ketzer, Katja Poppenhaeger, Martina Baratella +1
Planets orbiting young stars are thought to experience atmospheric evaporation as a result of the host stars' high magnetic activity. We study the evaporation history and expected…
A comparative study of two X2.2 and X9.3 solar flares observed with HARPS-N: Reconciling Sun-as-a-star spectroscopy and high-spatial resolution solar observations in the context of the solar-stellar connection
A. G. M. Pietrow, M. Cretignier, M. K. Druett +14
Stellar flares cannot be spatially resolved, which complicates ascertaining the physical processes behind particular spectral signatures. Due to their proximity to Earth, solar fla…
A Test of the Neutron Star Hypothesis for Fomalhaut b
K. Poppenhaeger, K. Auchettl, S. J. Wolk
Fomalhaut b is a directly imaged object in the debris disk of the star Fomalhaut. It has been hypothesized to be a planet, however there are issues with the observed colours of the…
YSOVAR: Mid-Infrared Variability in NGC 1333
L. M. Rebull, J. R. Stauffer, A. M. Cody +17
As part of the Young Stellar Object VARiability (YSOVAR) program, we monitored NGC 1333 for ~35 days at 3.6 and 4.5 um using the Spitzer Space Telescope. We report here on the mid-…
YSOVAR: mid-infrared variability of young stellar objects and their disks in the cluster IRAS 20050+2720
K. Poppenhaeger, A. M. Cody, K. R. Covey +12
We present a time-variability study of young stellar objects in the cluster IRAS 20050+2720, performed at 3.6 and 4.5 micron with the Spitzer Space Telescope; this study is part of…
Stellar magnetic activity and Star-Planet Interactions (invited review)
K. Poppenhaeger
Stellar magnetic activity is an important factor in the formation and evolution of exoplanets. Magnetic phenomena like stellar flares, coronal mass ejections, and high-energy emiss…
Young Stellar Object Variability (YSOVAR): Long Timescale Variations in the Mid-Infrared
L. M. Rebull, A. M. Cody, K. R. Covey +32
The YSOVAR (Young Stellar Object VARiability) Spitzer Space Telescope observing program obtained the first extensive mid-infrared (3.6 & 4.5 um) time-series photometry of the Orion…
Cool Stars and Space Weather
A. A. Vidotto, M. Jardine, A. C. Cameron +8
Stellar flares, winds and coronal mass ejections form the space weather. They are signatures of the magnetic activity of cool stars and, since activity varies with age, mass and ro…
A tale of two exoplanets: the inflated atmospheres of the Hot Jupiters HD 189733 b and CoRoT-2 b
K. Poppenhaeger, S. J. Wolk, J. H. M. M. Schmitt
Planets in close orbits around their host stars are subject to strong irradiation. High-energy irradiation, originating from the stellar corona and chromosphere, is mainly responsi…
YSOVAR: Mid-IR variability in the star forming region Lynds 1688
H. M. Günther, A. M. Cody, K. R. Covey +14
The emission from young stellar objects (YSOs) in the mid-IR is dominated by the inner rim of their circumstellar disks. We present an IR-monitoring survey of about 800 objects in…
X-ray emission from the super-Earth host GJ 1214
S. Lalitha, K. Poppenhaeger, K. P. Singh +2
Stellar activity can produce large amounts of high-energy radiation, which is absorbed by the planetary atmosphere leading to irradiation-driven mass-loss. We present the detection…
Magnetospheric Structure and Atmospheric Joule Heating of Habitable Planets Orbiting M-dwarf Stars
O. Cohen, J. J. Drake, A. Glocer +5
We study the magnetospheric structure and the ionospheric Joule Heating of planets orbiting M-dwarf stars in the habitable zone using a set of magnetohydrodynamic (MHD) models. The…
Indications for an influence of Hot Jupiters on the rotation and activity of their host stars
K. Poppenhaeger, S. J. Wolk
The magnetic activity of planet-hosting stars is an important factor to estimate the atmospheric stability of close-in exoplanets and the age of their host stars. It has long been…
Planets spinning up their host stars: a twist on the age-activity relationship
K. Poppenhaeger, S. J. Wolk
It is a long-standing question in exoplanet research if Hot Jupiters can influence the magnetic activity of their host stars. While cool stars usually spin down with age and become…
A magnetic cycle of tau Bootis? The coronal and chromospheric view
K. Poppenhaeger, H. M. Guenther, J. H. M. M. Schmitt
Tau Bootis is a late F-type main sequence star orbited by a Hot Jupiter. During the last years spectropolarimetric observations led to the hypothesis that this star may host a glob…
Non-thermal processes in coronae and beyond
K. Poppenhaeger, H. M. Guenther, P. Beiersdorfer +7
This contribution summarizes the splinter session "Non-thermal processes in coronae and beyond" held at the Cool Stars 17 workshop in Barcelona in 2012. It covers new developments…
Multi-wavelength observations of Proxima Centauri
B. Fuhrmeister, S. Lalitha, K. Poppenhaeger +5
We report simultaneous observations of the nearby flare star Proxima Centauri with VLT/UVES and XMM-Newton over three nights in March 2009. Our optical and X-ray observations cover…
A search for star-planet interactions in the upsilon Andromedae system at X-ray and optical wavelengths
K. Poppenhaeger, L. F. Lenz, A. Reiners +2
Close-in, giant planets are expected to influence their host stars via tidal or magnetic interaction. But are these effects strong enough in suitable targets known so far to be obs…
Coronal properties of planet-bearing stars
K. Poppenhaeger, J. Robrade, J. H. M. M. Schmitt
Do extrasolar planets affect the activity of their host stars? Indications for chromospheric activity enhancement have been found for a handful of targets, but in the X-ray regime,…