相关论文: VLBA determinations of the distances to nearby sta…

When observed with sufficiently high spatial resolution and sensitivity, star formation regions are unusually complex X-ray sources. Low-mass protostars and T Tauri stars, Herbig Ae/Be stars, OB and Wolf-Rayet stars are seen at levels $28…

A high optical depth to gravitational microlensing towards the galactic bulge is consistent with current models of the galactic bar. The low optical depth towards the LMC can probably be accounted for by the ordinary stars in our galaxy and…

We present the first period-luminosity and period-radius relation of Galactic RV Tauri variable stars. We have surveyed the literature for all variable stars belonging to this class and compiled the full set of their photometric and…

Observations of the rho Ophiuchi star forming region with VLT ANTU and ISAAC under 0.35" seeing conditions reveal two bipolar reflection nebulosities intersected by central dust lanes. The sources (OphE-MM3 and CRBR 2422.8-3423) can be…

We compile and analyze ~200 trigonometric parallaxes and proper motions of molecular masers associated with very young high-mass stars. These measurements strongly suggest that the Milky Way is a four-arm spiral. Fitting log-periodic…

We have measured trigonometric parallaxes for four water masers associated with distant massive young stars in the inner regions of the Galaxy using the VLBA as part of the BeSSeL Survey. G026.50$+$0.28. is located at the near end of the…

We present deep 1.8 cm (16 GHz) radio continuum imaging of seven young stellar objects in the Taurus molecular cloud. These objects have previously been extensively studied in the sub-mm to NIR range and their SEDs modelled to provide…

We present high-sensitivity ($\sigma_I\sim0.2-0.5$ mJy, $\sigma_{QU}\sim0.05$ mJy), high-resolution (0.12-0.2 arcsec) observations of polarized 872 $\mu$m dust emission from the young multiple system VLA 1623 in $\rho$ Ophiuchus and the…

We present high-resolution spectra (R ~ 49,000) of stars that have parallax measurements from the Hipparcos satellite and are projected along the line of sight to the two nearest known star forming clouds to the Sun: MBM12 and MBM20. The…

Previous star formation studies have, out of necessity, often defined a population of young stars confined to the proximity of a molecular cloud. Gaia allows us to examine a wider, three-dimensional structure of nearby star forming regions,…

We have performed a survey for substellar companions to young brown dwarfs in the Taurus star-forming region using the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. In these data, we have discovered a candidate…

Based on published data, we have produced a sample of 256 radio sources whose trigonometric parallaxes and proper motions were measured by VLBI. This sample contains Galactic masers associated with massive protostars and stars in active…

Accurate distances to local molecular clouds are critical for understanding the star and planet formation process, yet distance measurements are often obtained inhomogeneously on a cloud-by-cloud basis. We have recently developed a method…

This paper is dedicated to investigating the kinematic properties of the Lupus moving group of young stars with the primary objective of deriving individual parallaxes for each group member. We identify those stars in the Lupus star-forming…

We have performed the astrometry of H2O masers in the Galactic star-forming region Onsala 2 North (ON2N) with the VLBI Exploration of Radio Astrometry.We obtained the trigonometric parallax of 0.261+/-0.009 mas, corresponding to the…

Compact substructure is expected to arise in a starless core as mass becomes concentrated in the central region likely to form a protostar. Additionally, multiple peaks may form if fragmentation occurs. We present ALMA Cycle 2 observations…

We report a trigonometric parallax measurement with the Very Long Baseline Array for the water maser in the distant high-mass star-forming region G75.30+1.32. This source has a heliocentric distance of 9.25+-0.45 kpc, which places it in the…

Young stellar associations hold a star formation record that can persist for millions of years, revealing the progression of star formation long after the dispersal of the natal cloud. To identify nearby young stellar populations that trace…

We report results of astrometric VLBI observations toward a Mira variable star BX~Cam using the VLBI array "VERA". The observations were performed from February 2012 to November 2014. Obtained parallax is 1.73$\pm$0.03 mas corresponding to…

Distances to stars are key to revealing a three-dimensional view of the Milky Way, yet their determination is a major challenge in astronomy. Whilst the brightest nearby stars benefit from direct parallax measurements, fainter stars are…