Search Publications
New mercury-manganese stars and candidates from LAMOST DR4
Paunzen, E.; Bernhard, K.; Hümmerich, S.
Aims: The present work presents our efforts at identifying new mercury-manganese (HgMn/CP3) stars using spectra obtained with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST).
Methods: Suitable candidates were searched for among pre-selected early-type spectra from LAMOST DR4 using a modified version of the MKCLASS …
Coherent radio emission from a population of RS Canum Venaticorum systems
Callingham, J. R.; Shimwell, T. W.; Vedantham, H. K. +5 more
Coherent radio emission from stars can be used to constrain fundamental coronal plasma parameters, such as plasma density and magnetic field strength. It is also a probe of chromospheric and magnetospheric acceleration mechanisms. Close stellar binaries, such as RS Canum Venaticorum (RS CVn) systems, are particularly interesting as their heightene…
A global view on star formation: the GLOSTAR Galactic plane survey. III. 6.7 GHz methanol maser survey in Cygnus X
Beuther, Henrik; Wyrowski, Friedrich; Gong, Yan +16 more
The Cygnus X complex is covered by the Global View of Star Formation in the Milky Way (GLOSTAR) survey, an unbiased radio-wavelength Galactic plane survey, in 4-8 GHz continuum radiation and several spectral lines. The GLOSTAR survey observed the 6.7 GHz transition of methanol (CH3OH), an exclusive tracer of high-mass young stellar obje…
ESPRESSO mass determination of TOI-263b: an extreme inhabitant of the brown dwarf desert
Mustill, A. J.; Zapatero Osorio, M. R.; Zechmeister, M. +8 more
The TESS mission has reported a wealth of new planetary systems around bright and nearby stars amenable for detailed characterizations of planet properties and atmospheres. However, not all interesting TESS planets orbit around bright host stars. TOI-263 b is a validated ultra-short-period substellar object in a 0.56-day orbit around a faint (V = …
Transition from coherent cores to surrounding cloud in L1688
Caselli, Paola; Rosolowsky, Erik; Kirk, Helen +8 more
Context. Stars form in cold dense cores showing subsonic velocity dispersions. The parental molecular clouds display higher temperatures and supersonic velocity dispersions. The transition from core to cloud has been observed in velocity dispersion, but temperature and abundance variations are unknown.
Aims: We aim to measure the temperature …
Blue supergiants as tests for stellar physics
Meynet, Georges; Saio, Hideyuki; Georgy, Cyril
Context. Massive star evolution is still poorly understood, and observational tests are required to discriminate between different implementations of physical phenomena in stellar evolution codes.
Aims: By confronting stellar evolution models with observed properties of blue supergiants, such as pulsations, the chemical composition, and posit…
Evolutionary view through the starless cores in Taurus. Deuteration in TMC 1-C and TMC 1-CP
Ward-Thompson, D.; Kramer, C.; Fuente, A. +11 more
Context. The chemical and physical evolution of starless and pre-stellar cores are of paramount importance to understanding the process of star formation. The Taurus Molecular Cloud cores TMC 1-C and TMC 1-CP share similar initial conditions and provide an excellent opportunity to understand the evolution of the pre-stellar core phase.
Aims: …
Evidence for differentiation of the most primitive small bodies
Jorda, L.; Lamy, P.; Colas, F. +41 more
Context. Dynamical models of Solar System evolution have suggested that the so-called P- and D-type volatile-rich asteroids formed in the outer Solar System beyond Neptune's orbit and may be genetically related to the Jupiter Trojans, comets, and small Kuiper belt objects (KBOs). Indeed, the spectral properties of P- and D-type asteroids resemble …
Kinetic electrostatic waves and their association with current structures in the solar wind
Maksimovic, M.; Bale, S. D.; Chust, T. +21 more
Context. A variety of kinetic electrostatic and electromagnetic waves develop in the solar wind and the relationship between these waves and larger scale structures, such as current sheets and ongoing turbulence, remain a topic of investigation. Similarly, the instabilities producing ion-acoustic waves in the solar wind are still an open question.…
Capturing transient plasma flows and jets in the solar corona
Peter, H.; Chitta, L. P.; Solanki, S. K. +8 more
Intensity bursts in ultraviolet (UV) to X-ray wavelengths and plasma jets are typical signatures of magnetic reconnection and the associated impulsive heating of the solar atmospheric plasma. To gain new insights into the process, high-cadence observations are required to capture the rapid response of plasma to magnetic reconnection as well as the…