相关论文: Proplyds around a B1 star - 42 Orionis in NGC 1977

We report ALMA and VLA continuum observations that potentially identify the four youngest protostars in the Orion Molecular Clouds taken as part of the Orion VANDAM program. These are distinguished by bright, extended, irregular emission at…

We have studied the nuclei of 28 radio galaxies from the 3CR sample in the UV band. Unresolved nuclei (central compact cores, CCC) are observed in 10 of the 13 FR I, and in 5 of the 15 FR II. All sources that do not have a CCC in the…

We present a new mid-infrared (12.5micron) map of the BN/KL high-mass star-forming complex in Orion using the LWS instrument at Keck I. Despite poor weather we achieved nearly diffraction-limited images (FWHM = 0.38'') over a roughly 25'' X…

We present a near-IR survey for the visual multiples in the Orion molecular clouds region at separations between 100 and 1000 AU. These data were acquired at 1.6~$\mu$m with the NICMOS and WFC3 cameras on the Hubble Space Telescope.…

We use mid-IR images from the Spitzer Cygnus~X Legacy Survey to search for stellar bowshocks, a signature of early type "runaway" stars with high space velocities. We identify ten arc-shaped nebulae containing centrally located stars as…

We study the ionization structure of galactic outflows in 37 nearby, star forming galaxies with the Cosmic Origins Spectrograph on the Hubble Space Telescope. We use the O I, Si II, Si III, and Si IV ultraviolet absorption lines to…

We present evidence that the outflowing UV absorbers in Seyfert 1 galaxies arise primarily in their inner narrow (emission) line regions (NLRs), based on similarities in their locations, kinematics, and physical conditions. 1) Hubble Space…

We present the polarization images in the $J$, $H$, & $Ks$ bands of the Orion Molecular Cloud 1 South region. The polarization images clearly show at least six infrared reflection nebulae (IRNe) which are barely seen or invisible in the…

The demographics of the production and escape of ionizing photons from UV-faint early galaxies is a key unknown in discovering the primary drivers of reionization. With the advent of JWST it is finally possible to observe the rest-frame…

Located in the Orion Trapezium cluster, Theta 1 Orionis C is one of the youngest and nearest high-mass stars (O5-O7) and also known to be a close binary system. Using new multi-epoch visual and near-infrared bispectrum speckle…

Molecular oxygen, O_2, has been the target of ground-based and space-borne searches for decades. Of the thousands of lines of sight surveyed, only those toward Rho Oph and Orion H_2 Peak 1 have yielded detections of any statistical…

By comparing 3 constituents of Orion A (gas, protostars, and pre-main-sequence stars), both morhologically and kinematically, we derive the following. The gas surface density near the integral-shaped filament (ISF) is well represented by a…

Context: Increasingly, Oort Cloud comets are being discovered at great distances from the Sun and tracked over ever wider ranges of heliocentric distances as observational equipment improves. Aims: To investigate in detail how the original…

We present results of a 90 ksec Chandra X-ray observation of the young sigma Orionis cluster (age ~3 Myr) obtained with the High Energy Transmission Grating Spectrometer. We use the high resolution grating spectrum and moderate resolution…

We present submillimeter polarimetry at 850 micron toward the filamentary star-forming region associated with the reflection nebulosity NGC 2068 in Orion B. These data were obtained using the James Clerk Maxwell Telescope's SCUBA…

We discuss the theory of coupled ionization--dissociation fronts produced when molecular clouds are exposed to $\lambda < 1110$\AA\ radiation from hot stars. A steady, composite structure is developed, which generally includes an ionized…

(abridged) Our project endeavors to obtain a robust view of multiplicity among embedded Class I and Flat Spectrum protostars in a wide array of nearby molecular clouds to disentangle ``universal'' from cloud-dependent processes. We have…

IC 1274 is a faintly luminous nebula lying on the near surface of the Lynds 227 (L227) molecular cloud. Four luminous, early-type (B0-B5) stars are located within a spherical volume ~5' in diameter that appears to be clear of heavy…

The main accretion phase of protostars is characterized by the ejection of material in the form of jets/outflows. External UV irradiation can potentially have a significant impact on the excitation conditions within these outflows.…

The distance to the Orion Nebula Cluster (ONC) is estimated using the rotational properties of its low-mass pre main-sequence (PMS) stars. Rotation periods, projected equatorial velocities and distance-dependent radius estimates are used to…