ﻻ يوجد ملخص باللغة العربية
Recently, the Spitzer Space Telescope discovered L1014-IRS, a mid-infrared source with protostellar colors, toward the heretofore starless core L1014. We present deep near-infrared observations that show a scattered light nebula extending from L1014-IRS. This nebula resembles those typically associated with protostars and young stellar objects, tracing envelope cavities presumably evacuated by an outflow. The northern lobe of the nebula has an opening angle of ~100 degrees, while the southern lobe is barely detected. Its morphology suggests that the bipolar cavity and inferred protostellar disk is not inclined more than 30 degrees from an edge-on orientation. The nebula extends at least 8 from the source at Ks, strongly suggesting that L1014-IRS is embedded within L1014 at a distance of 200 pc rather than in a more distant cloud associated with the Perseus arm at 2.6 kpc. In this case, the apparently low luminosity of L1014-IRS, 0.090 Lsun, is consistent with it having a substellar mass. However, if L1014-IRS is obscured by a circumstellar disk, its luminosity and inferred mass may be greater. Using near-infrared colors of background stars, we investigate characteristics of the L1014 molecular cloud core. We determine a mass of 3.6 Msun for regions of the core with Av > 2 magnitudes. A comparison of the radial extinction profile of L1014 with other cores suggests that L1014 may be among the most centrally condensed cores known, perhaps indicative of the earliest stages of brown dwarf or star formation processes.
We report the analysis of near-infrared imaging, polarimetric and spectroscopic observations of the powerful radio galaxy 3C433, obtained with the HST and UKIRT telescopes. The high spatial resolution of HST allows us to study the near-nuclear region
Spitzer Space Telescope observations of a point-like source, L1014-IRS, close to the dust peak of the low-mass dense core L1014 have questioned its starless nature. The presence of an object with colors expected for an embedded protostar makes L1014-
We present observations of L1014, a dense core in the Cygnus region previously thought to be starless, but data from the Spitzer Space Telescope shows the presence of an embedded source. We propose a model for this source that includes a cold core, h
We investigate the star formation activity in a young star forming cluster embedded at the edge of the RCW 41 HII region. As a complementary goal, we aim at demonstrating the gain provided by Wide-Field Adaptive Optics instruments to study young clus
IGR J17454-2919 is a hard X-ray transient discovered by INTEGRAL on 2014 September 27. We report on our 20ks Chandra observation of the source, performed about five weeks after the discovery, as well as on INTEGRAL and Swift monitoring long-term obse