572 citations · 1k across the 21 of their papers we have counts for
21 papers
Spiral Morphology and Radial Migration: Kinematically heating, cooling, and cold
Kathryne J. Daniel, M. E. Wisz, Karen L. Masters +3
Transient spiral arms are known to drive radial redistribution of stars and thus could play a central role in shaping disk galaxies, including modifying, over time, the age, chemic…
The Milky Way Tomography with Subaru Hyper Suprime-Cam: Implications for the past orbit of the Large Magellanic Cloud
Yoshihisa Suzuki, Masashi Chiba, Rosemary F. G. Wyse
We report the discovery of diffuse stellar substructure in the Milky Way's outer halo toward Boötes, unveiled by deep imaging data of the Subaru/Hyper Suprime-Cam. This substructur…
The Milky Way Tomography with Subaru Hyper Suprime-Cam. II. Global halo structure
Yoshihisa Suzuki, Masashi Chiba, Rosemary F. G. Wyse +1
We investigate the structure of the Milky Way's stellar halo within 70 kpc of the Sun using a wide-field photometric catalog obtained from the Hyper Suprime-Cam (HSC) Subaru Strate…
Galactic Archaeology with the Subaru `Ōnohi`ula Prime Focus Spectrograph Strategic Program
Masashi Chiba, Rosemary F. G. Wyse, Evan N. Kirby +48
The recently commissioned Subaru `Ōnohi`ula Prime Focus Spectrograph (PFS) will obtain spectra from nearly 2,400 fibers that cover 1.24 square degrees. The 360 night Subaru Strateg…
Generalization from Low- to Moderate-Resolution Spectra with Neural Networks for Stellar Parameter Estimation: A Case Study with DESI
Xiaosheng Zhao, Yuan-Sen Ting, Rosemary F. G. Wyse +5
Cross-survey generalization is a critical challenge in stellar spectral analysis, particularly in cases such as transferring from low- to moderate-resolution surveys. We investigat…
Machine Learning Techniques to Distinguish Giant Stars from Dwarf Stars Using Only Photometry -- Pushing Redwards
Keyi Ding, Carrie Filion, Rosemary F. G. Wyse +6
We present our photometric method, which combines Subaru/HSC , g, and i band filters to distinguish giant stars in Local Group galaxies from Milky Way dwarf contamination. T…
The Extended Stellar Distribution in the Outskirts of the Ursa Minor Dwarf Spheroidal Galaxy
Kyosuke S. Sato, Sakurako Okamoto, Masafumi Yagi +7
We discover an extended distribution of main-sequence (MS) stars along the minor axis of the Ursa Minor (UMi) dwarf spheroidal galaxy (dSph). This study is enabled by deep, wide Su…
The Star Formation and Chemical Evolution Histories of Ursa Minor Dwarf Spheroidal Galaxy
Kyosuke S. Sato, Yutaka Komiyama, Sakurako Okamoto +8
We derive the star formation history (SFH) and chemical evolution history (CEH) of the Ursa Minor (UMi) dwarf spheroidal galaxy (dSph). We detect two distinct stellar populations t…
Constraints on asteroid-mass primordial black holes in dwarf galaxies using Hubble Space Telescope photometry
Nicolas Esser, Carrie Filion, Sven De Rijcke +4
Primordial black holes (PBHs) in the asteroid-mass range remain a viable and until now unconstrained dark matter (DM) candidate. If such PBHs exist, they could be captured by stars…
What can we learn from the Nitrogen abundance of High-z galaxies?
Massimo Stiavelli, Takahiro Morishita, Marco Chiaberge +9
We present measurements of the gas-phase Oxygen and Nitrogen abundances obtained by applying the direct method to JWST NIRspec spectroscopy for 6 galaxies at redshift g…
Uncertainty of line-of-sight velocity measurement of faint stars from low and medium resolution optical spectra
László Dobos, Alexander S. Szalay, Tamás Budavári +3
Massively multiplexed spectrographs will soon gather large statistical samples of stellar spectra. The accurate estimation of uncertainties on derived parameters, such as line-of-s…
Triangulum IV: A Possible Ultra-Diffuse Satellite of M33
Itsuki Ogami, Yutaka Komiyama, Masashi Chiba +8
We report the detection of a dwarf satellite candidate (Triangulum IV: Tri IV) of the Triangulum galaxy (M33) using the deep imaging of Subaru/Hyper Suprime-Cam (HSC). From the app…
Revealing mass distributions of dwarf spheroidal galaxies in the Subaru-PFS era
Kohei Hayashi, Laszlo Dobos, Carrie Filion +4
The Galactic dwarf spheroidal galaxies (dSphs) provide valuable insight into dark matter (DM) properties and its role in galaxy formation. Their close proximity enables the measure…
Chemodynamics of the Milky Way and disc formation history: insight from the RAVE and Gaia-ESO surveys
G. Kordopatis, R. F. G. Wyse, J. Binney
Multi-object spectrographs have opened a new window on the analyses of the chemo-dynamical properties of old Milky Way stars. These analyses allow us to trace back the internal mec…
New distances to RAVE stars
James Binney, Ben Burnett, Georges Kordopatis +16
Probability density functions are determined from new stellar parameters for the distance moduli of stars for which the RAdial Velocity Experiment (RAVE) has obtained spectra with…
Through thick and thin: Structure of the Galactic thick disc from extragalactic surveys
G. Kordopatis, V. Hill, M. Irwin +7
We aim to understand the accretion history of the Milky Way by exploring the vertical and radial properties of the Galactic thick disc. We study the chemical and kinematic properti…
The Sagittarius Streams in the Southern Galactic Hemisphere
Sergey E. Koposov, V. Belokurov, N. W. Evans +12
The structure of the Sagittarius stream in the Southern Galactic hemisphere is analysed with the Sloan Digital Sky Survey Data Release 8. Parallel to the Sagittarius tidal track, b…
The Ages of Stars
David R. Soderblom
The age of an individual star cannot be measured, only estimated through mostly model-dependent or empirical methods, and no single method works well for a broad range of stellar t…
Star Clusters in Pseudo-Bulges of Spiral Galaxies
Daiana Di Nino, Michele Trenti, Massimo Stiavelli +3
We present a study of the properties of the star-cluster systems around pseudo-bulges of late-type spiral galaxies using a sample of 11 galaxies with distances from 17 to 37 Mpc. S…
Probing Spectroscopic Variability of Galaxies & Narrow-Line Active Galactic Nuclei in the Sloan Digital Sky Survey
Ching-Wa Yip, Andrew Connolly, Daniel Vanden Berk +10
Under the unified model for active galactic nuclei (AGNs), narrow-line (Type 2) AGNs are, in fact, broad-line (Type 1) AGNs but each with a heavily obscured accretion disk. We woul…
The Spectacular Ionized Interstellar Medium of NGC55
Annette M. N. Ferguson, Rosemary F. G. Wyse, J. S. Gallagher
We present deep Halpha+[NII], [SII] (6716,6731A) and [OII] (3726,3729A) images of the highly inclined, actively star--forming SBm galaxy NGC 55, located in the nearby Sculptor Grou…