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Related papers: VERA astrometry toward the Perseus arm gap

200 papers

We present results of a survey of 14 star-forming regions from the Perseus spiral arm in CS(2-1) and 13CO(1-0) lines with the Onsala Space Observatory 20 m telescope. Maps of 10 sources in both lines were obtained. For the remaining sources…

Astrophysics of Galaxies · Physics 2017-09-08 M. S. Kirsanova , A. M. Sobolev , M. Thomasson

We report measurements of parallax and proper motion for four 22 GHz water maser sources as part of VERA Outer Rotation Curve project. All sources show Galactic latitudes of $>$ 2$^{\circ}$ and Galactocentric distances of $>$ 11 kpc at the…

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…

Aims. The main goal of this study is to detect the stellar overdensity associated with the Perseus arm in the anticenter direction. Methods. We used the physical parameters derived from Str\"omgren photometric data to compute the surface…

Astrophysics of Galaxies · Physics 2015-05-20 Maria Monguió , Preben Grosbøl , Francesca Figueras

We report the discovery of 31 new open clusters (OCs) identified in \textit{Gaia}~DR3 data through a systematic search over 220 adjacent $1^\circ\times1^\circ$ fields towards the Galactic anticentre, in the direction of the Perseus arm gap.…

Astrophysics of Galaxies · Physics 2026-03-30 F. A. Ferreira , M. S. Angelo , J. F. C. Santos , W. J. B. Corradi , F. F. S. Maia

We have measured the annual parallax of the H2O maser source associated with an infrared dark cloud MSXDC G034.43+00.24 from the observations with VERA (VLBI Exploration of Radio Astrometry). The parallax is 0.643 +/- 0.049 mas,…

The distance to the Vela pulsar (PSR B0833-45) has been traditionally assumed to be 500 pc. Although affected by a significant uncertainty, this value stuck to both the pulsar and the SNR. In an effort to obtain a model free distance…

Astrophysics · Physics 2009-11-06 P. A. Caraveo , A. De Luca , R. P. Mignani , G. F. Bignami

The Milky Way's disk-halo interface mediates energy and mass exchange between the interstellar thin disk and the halo. In the first detailed study of the Perseus arm's disk-halo interface, we combine HST/STIS and COS absorption spectra…

Astrophysics of Galaxies · Physics 2025-08-05 Ananya Goon Tuli , Nicolas Lehner , J. Christopher Howk , Todd M. Tripp , Andrew J. Fox , Frances H. Cashman

Over the past decade, the BeSSeL Survey and the VERA project have measured trigonometric parallaxes to approximately 250 massive, young stars using VLBI techniques. These sources trace spiral arms over nearly half of the Milky Way. What is…

Instrumentation and Methods for Astrophysics · Physics 2022-09-21 Mark J Reid

The radial distance to the co-rotation radius Rcoro (where the angular speed of the gas and stars in orbit around the Galactic Centre is equal to the angular speed of the spiral arm pattern) has often been predicted (at various places), but…

Astrophysics of Galaxies · Physics 2018-08-15 Jacques P Vallee

We report measurement of the trigonometric parallax of W51 Main/South using the Very Long Baseline Array (VLBA). We measure a value of 0.185 +/- 0.010 mas, corresponding to a distance of 5.41 (+0.31/-0.28) kpc. W51 Main/South is a…

Astrophysics of Galaxies · Physics 2015-05-19 M. Sato , M. J. Reid , A. Brunthaler , K. M. Menten

Astrometry can bring powerful constraints to bear on a variety of scientific questions about neutron stars, including their origins, astrophysics, evolution, and environments. Using phase-referenced observations at the VLBA, in conjunction…

We have obtained new rotation measure for 11 pulsars observed with the Effelsberg 100-m radio telescope, in the direction of the Perseus arm. Using a combination of 34 published and the 11 newly measured pulsar rotation measures we study…

Astrophysics · Physics 2009-04-13 Dipanjan Mitra , Richard Wielebinski , Michael Kramer , Axel Jessner

Background observations obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) toward l=95.4, b=36.1 show OVI 1032,1038 in emission. This sight line probes a region of stronger-than-average soft X-ray emission in the direction of…

Astrophysics · Physics 2016-08-30 Birgit Otte , W. Van Dyke Dixon , Ravi Sankrit

We determine the parallax and proper motion of the flaring, non-thermal radio star GMR A, a member of the Orion Nebula Cluster, using Very Long Baseline Array observations. Based on the parallax, we measure a distance of 389 +24/-21 parsecs…

Using the cross-matched data of Gaia DR2 and 2MASS Point Source Catalog, we investigated the surface density distribution of stars aged ~1 Gyr in the thin disk in the range of 90{\deg} <= l <= 270{\deg}. We selected 4,654 stars above the…

Astrophysics of Galaxies · Physics 2019-09-11 Yusuke Miyachi , Nobuyuki Sakai , Daisuke Kawata , Junichi Baba , Mareki Honma , Noriyuki Matsunaga , Kenta Fujisawa

We have obtained high-precision interferometric measurements of Vega with the CHARA Array and FLUOR beam combiner in the K' band at projected baselines between 103m and 273m. The measured visibility amplitudes beyond the first lobe are…

Observations of the "Warm Ionized Medium" (or, equivalently, the "Diffuse Ionized Gas") of the local ISM, the Perseus arm in the Milky Way, and also in several other galaxies show strong [NII]6563 (~H-alpha in some cases) and…

Astrophysics · Physics 2009-10-31 John S. Mathis

We report the results from a new, highly sensitive ($\Delta T_{mb} \sim 3 $mK) survey for thermal OH emission at 1665 and 1667 MHz over a dense, 9 x 9-pixel grid covering a $1\deg$ x $1\deg$ patch of sky in the direction of $l = 105\deg, b…

Astrophysics of Galaxies · Physics 2019-10-09 Michael P. Busch , Ronald J. Allen , Philip D. Engelke , David E. Hogg , David A. Neufeld , Mark G. Wolfire