338 citations · 1.3k across the 43 of their papers we have counts for
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Separating States in Astronomical Sources Using Hidden Markov Models: With a Case Study of Flaring and Quiescence on EV Lac
Robert Zimmerman, David A. van Dyk, Vinay L. Kashyap +1
We present a new method to distinguish between different states (e.g., high and low, quiescent and flaring) in astronomical sources with count data. The method models the underlyin…
Effect of Systematic Uncertainties on Density and Temperature Estimates in Coronae of Capella
Xixi Yu, Vinay L. Kashyap, Giulio Del Zanna +4
We estimate the coronal density of Capella using the O VII and Fe XVII line systems in the soft X-ray regime that have been observed over the course of the Chandra mission. Our ana…
A Hierarchical Model for the Ages of Galactic Halo White Dwarfs
Shijing Si, David A. van Dyk, Ted von Hippel +3
In astrophysics, we often aim to estimate one or more parameters for each member object in a population and study the distribution of the fitted parameters across the population. I…
A Bayesian Analysis of the Ages of Four Open Clusters
Elizabeth J. Jeffery, Ted von Hippel, David A. van Dyk +4
In this paper we apply a Bayesian technique to determine the best fit of stellar evolution models to find the main sequence turn off age and other cluster parameters of four interm…
Bayesian Analysis of Two Stellar Populations in Galactic Globular Clusters III: Analysis of 30 Clusters
R. Wagner-Kaiser, D. C. Stenning, A. Sarajedini +5
We use Cycle 21 Hubble Space Telescope (HST) observations and HST archival ACS Treasury observations of 30 Galactic Globular Clusters to characterize two distinct stellar populatio…
Bayesian Analysis of Two Stellar Populations in Galactic Globular Clusters I: Statistical and Computational Methods
D. C. Stenning, R. Wagner-Kaiser, E. Robinson +4
We develop a Bayesian model for globular clusters composed of multiple stellar populations, extending earlier statistical models for open clusters composed of simple (single) stell…
Bayesian Analysis of Two Stellar Populations in Galactic Globular Clusters II: NGC 5024, NGC 5272, and NGC 6352
R. Wagner-Kaiser, D. C. Stenning, E. Robinson +5
We use Cycle 21 Hubble Space Telescope (HST) observations and HST archival ACS Treasury observations of Galactic Globular Clusters to find and characterize two stellar populations…
Bayesian Analysis for Stellar Evolution with Nine Parameters (BASE-9): User's Manual
Ted von Hippel, Elliot Robinson, Elizabeth Jeffery +6
BASE-9 is a Bayesian software suite that recovers star cluster and stellar parameters from photometry. BASE-9 is useful for analyzing single-age, single-metallicity star clusters,…
A Bayesian Approach to Deriving Ages of Individual Field White Dwarfs
Erin M. O'Malley, Ted von Hippel, David van Dyk
We apply a self-consistent and robust Bayesian statistical approach to determining the ages, distances, and ZAMS masses of 28 field DA white dwarfs with ages of approximately 4 to…
A Bayesian Analysis of the Correlations Among Sunspot Cycles
Yaming Yu, David A. van Dyk, Vinay L. Kashyap +1
Sunspot numbers form a comprehensive, long-duration proxy of solar activity and have been used numerous times to empirically investigate the properties of the solar cycle. A number…
The White Dwarf Age of NGC 2477
Elizabeth J. Jeffery, Ted von Hippel, Steven DeGennaro +3
We present deep photometric observations of the open cluster NGC 2477 using HST/WFPC2. By identifying seven cluster white dwarf candidates, we present an analysis of the white dwar…