scholarly journals Open clusters and associations in the Gaia era

2016 ◽  
Vol 80-81 ◽  
pp. 73-114 ◽  
Author(s):  
E. Moraux
Keyword(s):  
Open Clusters ◽  
Open Clusters And Associations

scholarly journals A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS) – III. Exploring the properties of young associations through their variables, dippers, and candidate exoplanets

2020 ◽  
Vol 498 (4) ◽  
pp. 5972-5989
Author(s):  
D Nardiello
Keyword(s):  
Variable Stars ◽  
Open Clusters ◽  
Light Curves ◽  
Quality Data ◽  
Stellar Systems ◽  
Satellite Mission ◽  
Open Clusters And Associations ◽  
Star Forming ◽  
Star Forming Regions ◽  
Strong Candidate

ABSTRACT Young associations in star-forming regions are stellar systems that allow us to understand the mechanisms that characterize the stars in their early life and what happens around them. In particular, the analysis of the discs and of the exoplanets around young stars allows us to know the key processes that prevail in their evolution and understand the properties of the exoplanets orbiting older stars. The Transiting Exoplanet Survey Satellite mission is giving us the opportunity to extract and analyse the light curves of association members with high accuracy, but the crowding that affects these regions makes difficult the light curve extraction. In the PATHOS project, cutting-edge tools are used to extract high-precision light curves and identify variable stars and transiting exoplanets in open clusters and associations. In this work, I analysed the light curves of stars in five young (≲10 Myr) associations, searching for variables and candidate exoplanets. Using the rotational periods of the association members, I constrained the ages of the five stellar systems (∼2–10 Myr). I searched for dippers, and I investigated the properties of the dust that forms the circumstellar discs. Finally, I searched for transiting signals, finding six strong candidate exoplanets. No candidates with radius RP ≲ 0.9 RJ have been detected, in agreement with the expectations. The frequency of giant planets resulted to be ∼2–3 per cent, higher than that expected for field stars (≲ 1 per cent); the low statistic makes this conclusion not strong, and new investigations on young objects are mandatory to confirm this result.

Independent distance determinations to Milky Way Cepheids in open clusters and associations. 1: The binary Cepheid DL CAS in NGC 129

1994 ◽  
Vol 107 ◽  
pp. 2093 ◽  
Author(s):  
Wolfgang P. Gieren ◽  
Douglas L. Welch ◽  
Jean-Claude Mermilliod ◽  
Jaymie M. Matthews ◽  
Gisela Hertling
Keyword(s):  
Milky Way ◽  
Open Clusters ◽  
Open Clusters And Associations

Cepheids in open clusters and associations

1983 ◽  
Vol 275 ◽  
pp. 732 ◽  
Author(s):  
J. D. Fernie ◽  
R. McGonegal
Keyword(s):  
Open Clusters ◽  
Open Clusters And Associations

scholarly journals Independent Distance Determinations to Milky Way Cepheids in Open Clusters: A progress report on four stars

1995 ◽  
Vol 155 ◽  
pp. 361-362
Author(s):  
Wolfgang P. Giere ◽  
Jaymie M. Matthews ◽  
Jean-Claude Mermilliod ◽  
Douglas Welch
Keyword(s):  
Surface Brightness ◽  
Milky Way ◽  
Zero Point ◽  
Progress Report ◽  
Open Clusters ◽  
Open Clusters And Associations ◽  
Preliminary Results

AbstractWe have undertaken a programme to calibrate the Cepheid PL relation zero-point by obtaining distances of Cepheids in open clusters and associations via the visual surface brightness technique. Results are now available for four stars (SZ Tau, CF Cas, CV Mon and DL Cas) and others are currently under analysis. Preliminary results suggest the ‘ZAMS-fitting’ distances to the host clusters are systematically smaller than those we derive from Cepheid surface brightnesses.

scholarly journals Wolf-Rayet Stars in Open Clusters and Associations

1982 ◽  
Vol 99 ◽  
pp. 539-543
Author(s):  
Ingemar Lundström ◽  
Björn Stenholm
Keyword(s):  
Open Cluster ◽  
Angular Distance ◽  
Open Clusters ◽  
Line Of Sight ◽  
Open Clusters And Associations ◽  
Cluster Centre ◽  
Cluster Data ◽  
Angular Radius

We have made a search for line-of-sight coincidences between WR stars and open clusters using the new catalogue of galactic WR stars (van der Hucht et al., 1981, called the HCLS catalogue) and the catalogue of open cluster data (Lyngå and Lundström, 1980). As a measure of the separation we used the angular distance between the WR star and the cluster centre expressed with the cluster angular radius, r', as unit.

Independent Distance Determinations to Milky Way Cepheids in Open Clusters and Associations. III. CV MON in Anon Van Den Bergh

1996 ◽  
Vol 111 ◽  
pp. 2059 ◽  
Author(s):  
Wolfgang P. Gieren ◽  
Jean-Claude Mermilliod ◽  
Jaymie M. Mathews ◽  
Douglas L. Welch
Keyword(s):  
Milky Way ◽  
Open Clusters ◽  
Open Clusters And Associations

scholarly journals The dependence of maximum starspot amplitude and the amplitude distribution on stellar properties

2010 ◽  
Vol 6 (S273) ◽  
pp. 469-473
Author(s):  
Steven H. Saar ◽  
Michelle Dyke ◽  
Søren Meibom ◽  
Sydney A. Barnes
Keyword(s):  
Simple Model ◽  
Maximum Level ◽  
Amplitude Distribution ◽  
Open Clusters ◽  
Photometric Data ◽  
Rossby Number ◽  
Long Tail ◽  
Open Clusters And Associations ◽  
Complex Variation ◽  
Stellar Properties

AbstractWe combine photometric data from field stars, plus over a dozen open clusters and associations, to explore how the maximum photometric amplitude (Amax) and the distribution of amplitudes varies with stellar properties. We find a complex variation of Amax with inverse Rossby number Ro−1, which nevertheless can be modeled well with a simple model including an increase in Amax with rotation for low Ro−1, and a maximum level. Amax may then be further affected by differential rotation and a decline at the highest Ro−1. The distribution of Aspot below Amax varies with Ro−1 : it peaks at low Aspot with a long tail towards Amax for low Ro−1, but is more uniformly distributed at higher Ro−1. We investigate further dependences of the Aspot distributions on stellar properties, and speculate on the source of these variations.

Sign in / Sign up

Export Citation Format

Share Document