English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The stellar composition of the Tycho-2 Catalogue in the range $0.75<B-V<1.25$has been reproduced through Monte Carlo simulations. For young and old stars ofthe red giant clump (RGC), the red giant branch, subgiants, red dwarfs, andthick-disk giants, we have specified the distributions in coordinates,velocities, $B-V$, and $M_V$ as a function of $B-V$ and calculated theirreduced proper motions, photometric distances from the $(B-V)-M_V$ calibration,and photoastrometric distances from the reduced proper motion -- $M_V$calibration. Our simulations have shown the following: (1) a sample ofthin-disk giants within 500 pc with an admixture of less than 10\% of otherstars can be produced; (2) a sample of dwarfs within 100 pc almost without anyadmixture of other stars can be produced; (3) the Local Spiral Arm affects theRGC composition of any magnitude-limited catalog in favor of giants youngerthan 2 Gyr; (4) the samples produced using reduced proper motions can be usedfor kinematic studies, provided that the biases of the quantities beingdetermined are simulated and taken into account; (5) the photometric distancescorrelate with the photoastrometric ones because of the correlation between theproper motion and magnitude; (6) the photometric distances are closer to thetrue ones for the red giant branch and red dwarfs as the categories of starswith a clear $(B-V)-M_V$ relation, while the photoastrometric distances arecloser to the true ones for the RGC, subgiants, and thick-disk giants; (7) thecalculated distances differ systematically from the true ones, but they can beused to analyze the three-dimensional distribution of stars. Our simulationsconfirm the validity of our previous selection of RGC stars from Tycho-2.

Using the reduced proper motions of Tycho-2 stars with B-V from 0.75 to 1.25: Monte Carlo simulations