Related papers: Quantitative Stellar Spectral Classification. IV. …
We have developed a data reduction procedure to extract multiple spectra from a single two-dimensional Space Telescope Imaging Spectrograph (STIS) image of a crowded stellar field. This paper provides a description of our new technique,…
I will show that photometry -- if extending over a reasonable choice of passbands -- can give fairly precise information about young star clusters and their evolutionary state. Optical colors alone are known to leave severe ambiguities due…
We calibrate spectrophotometric optical spectra of 32 stars commonly used as standard stars, referenced to 14 stars already on the HST-based CALSPEC flux system. Observations of CALSPEC and non-CALSPEC stars were obtained with the SuperNova…
A new analysis of CCD-based BVRI broad-band photometry for the globular cluster NGC2419 is presented, based on 340 CCD images either donated by colleagues or retrieved from public archives. The calibrated results have been made available…
Nowadays, Machine Learning techniques offer fast and efficient solutions for classification problems that would require intensive computational resources via traditional methods. We examine the use of a supervised Random Forest to classify…
CONTEXT. Many massive stars have nearby companions whose presence hamper their characterization through spectroscopy. AIMS. We want to continue obtaining spatially resolved spectroscopy of close massive visual binaries to derive their…
The goals of this work are to develop a new method to separate early and late type stellar components of a dense stellar cluster based on narrow band filters, to apply it to the central parsec of the GC, and to conduct a population analysis…
We have created a digital spectral library, using low resolution optical spectra, of photometric and spectral standard stars. The data were acquired using the Cassegrain Spectrograph installed on the 1.9m Radcliffe telescope at the South…
We present combined optical/near-IR photometry (BVIK) for six open clusters - M35, M37, NGC 1817, NGC 2477, NGC 2420, and M67. The open clusters span an age range from 150 Myr to 4 Gyr and have metal abundances from [Fe/H] = -0.3 to +0.09…
We continue our deep optical imaging survey of the Virgo cluster using the CWRU Burrell Schmidt telescope by presenting B-band surface photometry of the core of the Virgo cluster in order to study the cluster's intracluster light (ICL). We…
Integrated spectra have been obtained of 31 star clusters in the Magellanic Clouds (MC) and of 4 Galactic globular clusters. The spectra cover the wavelength range 3500 -- 4700 Angstroms at a resolution of 3.2 Angstroms FWHM. The MC…
We present measurements of dust reddening using the colors of stars with spectra in the Sloan Digital Sky Survey. We measure reddening as the difference between the measured and predicted colors of a star, as derived from stellar parameters…
We present a BVI optical photometric study of the old open cluster Ruprecht 6 using the data obtained with the SMARTS 1.0 m telescope at the CTIO, Chile. Its color-magnitude diagrams show the clear existence of the main-sequence stars, of…
The stellar masses of galaxies are measured using integrated light via several methods -- however, few of these methods were designed for low-mass ($M_{\star}\lesssim10^{8}\rm{M_{\odot}}$) "dwarf" galaxies, whose properties (e.g.,…
We present integrated JHK_s 2MASS photometry and a compilation of integrated-light optical photoelectric measurements for 84 star clusters in the Magellanic Clouds. These clusters range in age from ~200 Myr to >10 Gyr, and have [Fe/H]…
Photometric measurements are prone to systematic errors presenting a challenge to low-amplitude variability detection. In search for a general-purpose variability detection technique able to recover a broad range of variability types…
High-quality stellar spectra are in great demand now - they are the most important ingredient in the stellar population synthesis to study galaxies and star clusters. Here we describe the procedures to increase the quality of flux…
The Galactic O-Star Spectroscopic Survey (GOSSS) is obtaining high quality R~2500 blue-violet spectroscopy of all Galactic stars ever classified as of O type with B < 12 and a significant fraction of those with B = 12-14. As of June 2013,…
Distance measures on a coherent scale around the sky are required to address the outstanding cosmological problems of the Hubble Constant and of departures from the mean cosmic flow. The correlation between galaxy luminosities and rotation…
By applying quantum chemical calculation, interstellar infrared spectrum was categorized to three classes. Type-A show unusual feature of strong peaks at 11.3,12.9, and 14.0 micrometer. Usually observed 6.2, 7.7, and 8.6 micrometer bands…