Harinder Pal Singh

Examination of Scaling Relationships Involving Penetration Distance at the Bottom of a Stellar Convective Envelope

A number of studies in the recent past have proposed a variety of scaling relationships among the penetration depth (Δd) at the bottom of a convective region, the vertical velocity of the fluid (Vz), and the input flux (Fb). While a relationship of the form Δd ∝ V has been proposed by Schmitt and coworkers on the basis of the equations of motion for buoyant plumes, Zahn proposed a similar relationship based on scaling arguments. The relationships involving Δd, Vz, and the input flux are based on recent two-dimensional numerical simulations by Hurlburt and coworkers. All these scalings were recently looked into by Singh, Roxburgh, & Chan, who performed full three-dimensional simulations of turbulent compressible convection for a stable-unstable-stable sandwich configuration. In the present study, we numerically solve the full set of Navier-Stokes equations in three dimensions in order to study the behavior of convective motions penetrating into the bottom stable layer. We take up a series of models differing in resolution or mesh size and aspect ratio with a view to examine, in greater detail, the scaling relationships between the penetration distance and other flow parameters.

Large Magellanic Cloud Near-infrared Synoptic Survey. IV. Leavitt Laws for Type II Cepheid Variables

We present time-series observations of Population \rom{2} Cepheids in the Large Magellanic Cloud at near-infrared (

E(B-V) DETERMINATIONS OF O AND B STARS USING ARTIFICIAL NEURAL NETWORKS

JHK_s

On multimode pulsations of degenerate stellar models

) wavelengths. Our sample consists of 81 variables with accurate periods and optical (

A 3D Automated Classification Scheme for the TAUVEX data pipeline

VI

Growth of Bulges in Disk Galaxies Since z ∼ 1

) magnitudes from the OGLE survey, covering various subtypes of pulsators (BL Herculis, W Virginis and RV Tauri). We generate light curve templates using high-quality

A comparative study of multiwavelength theoretical and observed light curves of Cepheid variables

I

Partially degenerate nonrelativistic isothermal gas spheres in the presence of a magnetic field

-band data in the LMC from OGLE and

Radial oscillations of finite-temperature white dwarfs

K_s

U-SmART - SMALL APERTURE ROBOTIC TELESCOPES FOR UNIVERSITIES

-band data in the Galactic Bulge from VVV and use them to obtain robust mean magnitudes. We derive Period-Luminosity (P-L) relations in the near-infrared and Period-Wesenheit (P-W) relations by combining optical and near-infrared data. Our P-L and P-W relations are consistent with published work when excluding long-period RV Tauris. We find that Pop II Cepheids and RR Lyraes follow the same P-L relations in the LMC. Therefore, we use trigonometric parallax from the {\it Gaia DR1} for VY~Pyx and the {\it Hubble Space Telescope} parallaxes for