855 citations · 2.7k across the 10 of their papers we have counts for
10 papers
How Robust is the Cosmic Distance with Tip of Red Giant Branch against Stellar Population Variations?
Chul Chung, Young-Wook Lee, Suk-Jin Yoon +10
The tip of the red giant branch (TRGB) provides a key standard candle for extragalactic distance measurements and for refining the Hubble constant. We test its robustness by quanti…
UBVRIz Light Curves of 51 Type II Supernovae
Lluís Galbany, Mario Hamuy, Mark M. Phillips +34
We present a compilation of UBV RIz light curves of 51 type II supernovae discovered during the course of four different surveys during 1986 to 2003: the Cerro Tololo Supernova Sur…
Angular Momentum Loss from Cool Stars: An Empirical Expression and Connection to Stellar Activity
Sydney A. Barnes, Yong-Cheol Kim
We show here that the rotation period data in open clusters allow the empirical determination of an expression for the rate of loss of angular momentum from cool stars on the main…
The Origin of T Tauri X-ray Emission: New Insights from the Chandra Orion Ultradeep Project
Thomas Preibisch, Yong -Cheol Kim, Fabio Favata +8
We use the data of the Chandra Orion Ultradeep Project (COUP) to study the nearly 600 X-ray sources that can be reliably identified with optically well characterized T Tauri stars…
Super Helium-Rich Population and the Origin of Extreme Horizontal-Branch Stars in Globular Clusters
Young-Wook Lee, Seok-Joo Joo, Sang-Il Han +7
Recent observations for the color-magnitude diagrams (CMDs) of the massive globular cluster Omega Centauri have shown that it has a striking double main sequence (MS), with a minor…
Y2 Isochrones with an Improved Core Overshoot
Pierre Demarque, Jong-Hak Woo, Yong-Cheol Kim +1
Convective core overshoot affects stellar evolution rates and the dating of stellar populations. In this paper, we provide a patch to the isochrones with an improved treatmen…
The Y^2 Stellar Evolutionary Tracks
Sukyoung K. Yi, Yong -Cheol Kim, Pierre Demarque
We present a database of the latest stellar models of the (Yonsei-Yale) collaboration. This database contains the stellar evolutionary tracks from the pre-main-sequence birth…
The YY Isochrones for alpha-element Enhanced Mixtures
Yong -Cheol Kim, Pierre Demarque, Sukyoung K. Yi +1
We present a new set of isochrones in which the effect of the alpha-element enhancement is fully incorporated. These isochrones are an extension of the already published set of YY…
Towards Better Age Estimates for Stellar Populations: The Y^2 Isochrones for Solar Mixture
S. Yi, P. Demarque, Y. -C. Kim +4
We have constructed a new set of isochrones, called the Y^2 Isochrones, that represent an update of the Revised Yale Isochrones (RYI), using improved opacities and equations of sta…
On the UV Bright Phase of Metal-Rich Horizontal-Branch Stars
Sukyoung Yi, Pierre Demarque, Yong-Cheol Kim
We consider the origin of the UV bright phase of metal-rich helium-burning stars, the slow blue phase (SBP), that was predicted by various earlier works. Based on improved physics…