相关论文: Exocomets: A spectroscopic survey

The vast majority of extrasolar planets are detected by indirect detection methods such as transit monitoring and radial velocity measurements. While these methods are very successful in detecting short-periodic planets, they are mostly…

We describe EPIC 205718330 and EPIC 235240266, two systems identified in the K2 data whose light curves contain episodic drops in brightness with shapes and durations similar to those of the young "dipper" stars, yet shallower by ~1-2…

Analyzing exoplanets detected by radial velocity or transit observations, we determine the multiplicity of exoplanet host stars in order to study the influence of a stellar companion on the properties of planet candidates. Matching the host…

The majority of discovered exoplanets have been observed orbiting field stars as opposed to within a star cluster. To determine whether the lack of observed exoplanets in star clusters is due to gravitational perturbations or observational…

To understand the influence of additional wide stellar companions on planet formation, it is necessary to determine the fraction of multiple stellar systems amongst the known extrasolar planet population. We target recently discovered…

The HOSTS (Hunt for Observable Signatures of Terrestrial Systems) survey searches for dust near the habitable zones (HZs) around nearby, bright main sequence stars. We use nulling interferometry in N band to suppress the bright stellar…

We conduct a comprehensive search for transiting exomoons and exosatellites within 44 archival Spitzer light curves of 32 substellar worlds with estimated masses ranging between 3-30M$_{\rm Jup}$. This sample's median host mass is 16M$_{\rm…

Accurate stellar parameters are needed in numerous domains of astrophysics. The position of stars on the H-R diagram is an important indication of their structure and evolution, and it helps improve stellar models. Furthermore, the age and…

Due to their extremely small luminosity compared to the stars they orbit, planets outside our own Solar System are extraordinarily difficult to detect directly in optical light. Careful photometric monitoring of distant stars, however, can…

Variable red- and blue-shifted absorption features observed in the Ca ii K line towards the A-type shell star $\phi$ Leo have been suggested by us in a previous work to be likely due to solid, comet-like bodies in the circumstellar (CS)…

We present low resolution (R approximately 250) spectroscopy in the near-IR (0.8 to 2.5um) of the EXor variables. These are the initial results (obtained during the period 2007-2008) from a long term photometric and spectroscopic program…

The COROT space mission will monitor several target fields for up to 150 days to perform asteroseismology and to search for extrasolar planets by photometric transits. Variable stars in the target fields are important objects for additional…

Of the over 200 known extrasolar planets, 14 exhibit transits in front of their parent stars as seen from Earth. Spectroscopic observations of the transiting planets can probe the physical conditions of their atmospheres. One such technique…

What makes the study of exoplanetary atmospheres so hard is the extraction of its tiny signal from observations, usually dominated by telluric absorption, stellar spectrum and instrumental noise. The High Resolution Spectroscopy has emerged…

We analyse absorption characteristics and physical conditions of extraplanar intermediate- and high-velocity gas to study the distribution of the neutral and weakly ionised Milky Way halo gas and its relevance for the evolution of the Milky…

In this article we present a detailed spectroscopic analysis of more than 50 extra-solar planet host stars. Stellar atmospheric parameters and metallicities are derived using high resolution and high S/N spectra. The spectroscopy results,…

Observations at 70 microns with the Spitzer Space Telescope have detected several stellar systems within 65 pc of the Sun. Of 18 presumably young systems detected in this study, as many as 15 have 70-micron emission in excess of that…

We present Spitzer observations and McDonald Observatory Smith Telescope and Anglo-Australian Telescope high spectral resolution optical observations of 4 nearby stars with variable or anomalous optical absorption, likely caused by…

We conducted a survey for infrared excess emission from 16 nearby main sequence shell stars using the Multiband Imaging Photometer for Spitzer (MIPS) on the Spitzer Space Telescope. Shell stars are early-type stars with narrow absorption…

We present here the analysis of 30 gaseous extrasolar planets, with temperatures between 600 and 2400 K and radii between 0.35 and 1.9 $R_\mathrm{Jup}$. The quality of the HST/WFC3 spatially scanned data combined with our specialized…