相关论文: Revealing the fastest component of the DG Tau outf…

FU Tau belongs to a rare class of young, wide brown dwarf binaries. We have resolved the system in a Chandra X-ray observation and detected only the primary, FU Tau A. Hard X-ray emission, presumably from a corona, is present but,…

The Be star zeta Tau was recently reported to be a gamma Cas analog; that is, it displays an atypical (bright and hard) X-ray emission. The origin of these X-rays remains debated.The first X-ray observations indicated a very large…

We present observations of four T Tauri stars using long baseline infrared interferometry from the Palomar Testbed Interferometer. The target sources, T Tau N, SU Aur, RY Tau and DR Tau, are all known to be surrounded by dusty circumstellar…

Past X-ray observations of the nearby luminous quasar PDS 456 (at $z=0.184$) have revealed a wide angle accretion disk wind (Nardini et al. 2015), with an outflow velocity of $\sim-0.25c$, as observed through observations of its…

We analyze image and spectral data from $\approx$365~ks of observations from the {\it Chandra} X-ray Observatory of the nearby, edge-on starburst galaxy NGC 253 to constrain properties of the hot phase of the outflow. We focus our analysis…

We present a set of controlled hydrodynamical simulations to study the effects of strong galactic outflows on the density and temperature structures, and associated X-ray signatures, of extra-planar and circumgalactic gas. We consider three…

In classical T Tauri stars, X-rays are produced by two plasma components: a hot low-density plasma, with frequent flaring activity, and a high-density lower temperature plasma. The former is coronal plasma related to the stellar magnetic…

Multiwavelength radiation from relativistic particles accelerated at shocks in novae and other astrophysical sources carries a wealth of information about the outflow properties and the microphysical processes at work near the shocks. The…

We have used the Extreme Ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft to observe large areas of outflow near an active region. These outflows are seen to persist for at least 6 days. The emission line profiles suggest…

We study the inner region of the circumstellar disk around the TTauri star RY Tau. Our aim is to find a physical description satisfying the available interferometric data, obtained with the mid-infrared interferometric instrument at the…

The disk-outflow connection is thought to play a key role in extracting excess angular momentum from a forming proto-star. Though jet rotation has been observed in a few objects, no rotation of molecular outflows has been unambiguously…

We have detected circumstellar molecular gas around a small sample of T Tauri stars through aperture synthesis imaging of CO(2-1) emission at ~2-3'' resolution. RY Tauri, DL Tauri, DO Tauri, and AS 209 show resolved and elongated gaseous…

We calculate the X-ray emission from the shocked fast wind blown by the central stars of planetary nebulae (PNs) and compare with observations. Using spherically symmetric self similar solutions, we calculate the flow structure and X-ray…

A number of giant HII regions are associated with soft diffuse X-ray emission. Among these, the Carina nebula possesses the brightest soft diffuse emission. The required plasma temperature and thermal energy can be produced by collisions or…

The line emission from a growing number of Herbig-Haro jets can be observed and resolved at angular distances smaller than a few arcseconds from the central source. The interpretation of this emission is problematic, since the simplest…

(Note: this is a shortened version of the original "structured" (A&A format) abstract.) The 12.81 micrometer [NeII] line has recently gained interest as a potential tracer of gas in the tenuous surface layers of circumstellar disks. The…

We present a spectral analysis of 30 T Tauri stars observed with the Hamilton echelle spectrograph over more than a decade. One goal is to test magnetospheric accretion model predictions. Observational evidence previously published…

The connection between X-ray weakness and powerful X-ray outflows is both expected in a scenario where outflows are connected with radiation-driven winds, and observed in several sources, both in the local Universe and at high redshift.…

We have analyzed GHRS data of eight Classical T Tauri stars (CTTSs) and one Weak T Tauri star (WTTS). The GHRS data consist of an spectral range 40 A wide centered on 2800 A. For 4 of the CTTS we have nearly simultaneous optical…

We analyze the X-ray spectrum of the quasar PG1211+143 observed with the CCD and grating spectrometers on board XMM-Newton. Using an ion by ion fitting model we find an outflow component of about 3000 km/s that includes absorption lines of…