Search Publications
A stellar census in globular clusters with MUSE: A spectral catalogue of emission-line sources
Weilbacher, Peter M.; Kollatschny, Wolfram; Kamann, Sebastian +6 more
Aims: Globular clusters produce many exotic stars due to a much higher frequency of dynamical interactions in their dense stellar environments. Some of these objects were observed together with several hundred thousand other stars in our MUSE survey of 26 Galactic globular clusters. Assuming that at least a few exotic stars have exotic spectr…
Discovery and Seismic Analysis of an EL CVn-type Binary with Hybrid δ Sct-γ Dor Pulsations
Chen, X. H.; Wang, K.; Zhang, X. B. +2 more
We report the discovery of an EL CVn-type binary consisting of a low-mass, pre-helium white dwarf and the first detection of hybrid δ Sct-γ Dor pulsations in such binary systems. Based on the four years Kepler data, we determined comprehensive photometric solution of the eclipsing binary KIC 8113154. The light-curve modeling reveals that it is a d…
The volume of water required to carve the martian valley networks: Improved constraints using updated methods
Head, James W.; Rosenberg, Eliott N.; Palumbo, Ashley M. +2 more
The martian valley networks are a key piece of evidence for the presence of liquid water on early Mars, and understanding their formation conditions can provide valuable insight into the nature of the early climate. Previous studies have used various methods to estimate the volume of water required to carve the valley networks, with results rangin…
Two cold belts in the debris disk around the G-type star NZ Lupi
Avenhaus, H.; Augereau, J. -C.; Henning, T. +36 more
Context. Planetary systems hold the imprint of the formation and of the evolution of planets especially at young ages, and in particular at the stage when the gas has dissipated leaving mostly secondary dust grains. The dynamical perturbation of planets in the dust distribution can be revealed with high-contrast imaging in a variety of structures.…
Hybrid modeling of cometary plasma environments. II. Remote-sensing of a cometary bow shock
Kallio, E.; Nilsson, H.; Simon Wedlund, C. +3 more
Context. The ESA Rosetta probe has not seen direct evidence of a fully formed bow shock at comet 67P/Churyumov-Gerasimenko (67P). Ion spectrometer measurements of cometary pickup ions measured in the vicinity of the nucleus of 67P are available and may contain signatures of the large-scale plasma environment.
Aims: The aim is to investigate t…
Student Dust Counter: Status report at 38 AU
Stern, S. A.; Szalay, J. R.; Spencer, J. +8 more
The Student Dust Counter (SDC) is an in-situ dust detector aboard the New Horizons spacecraft observing the distribution of interplanetary dust particles (IDPs) with mass >10-12 g or approximately 0.5 µm in radius. New Horizons was launched on January 19th, 2006 and performed a fly-by of the Pluto system on July 14th, 2015. SDC…
Study of the long-term evolution of the accretion dynamics of GX 339-4
Mandal, S.; Aneesha, U.; Sreehari, H.
We study the dynamical behaviour of the galactic black hole source GX 339-4 during 2002-2011 outbursts using RXTE, Swift-XRT, XMM-Newton (PN) archival data. We present the spectral evolution of the source using four outburst data and discuss their similarities and differences between outbursts. We infer that the second peak in the 2002/03 and 2004…
Using Multiwavelength Variability to Explore the Connection among X-Ray Emission, the Far-ultraviolet H2 Bump, and Accretion in T Tauri Stars
Reynolds, M.; Grant, S.; Espaillat, C. C. +1 more
The high-energy radiation fields of T Tauri stars (TTS) should affect the surrounding circumstellar disk, having implications for disk transport and heating. Yet observational evidence of the effect of high-energy fields on disks is scarce. Here we investigate the connection between X-ray emission and the innermost gas disk by leveraging the varia…
Dynamics of wind and the dusty environments in the accreting T Tauri stars RY Tauri and SU Aurigae
Grankin, K. N.; Irsmambetova, T. R.; Gahm, G. F. +10 more
Classical T Tauri stars with ages of less than 10 Myr possess accretion discs. Magnetohydrodynamic processes at the boundary between the disc and the stellar magnetosphere control the accretion and ejections gas flows. We carried out a long series of simultaneous spectroscopic and photometric observations of the classical T Tauri stars, RY Tauri a…
Probability of magnification in the HubbleFrontier Fields clusters
Diego, J. M.; Bernstein, G. M.; Vega-Ferrero, J.
We present free-form gravitational lensing models derived with the WSLAP+ code for the six HubbleFrontier Fields clusters using the latest data available from the Frontier Fields Lensing Models v.4 collaboration. We present magnification maps in the lens plane and caustic maps in the source plane. From these maps, we derive the probability of magn…