Search Publications
Not That Simple: The Metallicity Dependence of the Wide Binary Fraction Changes with Separation and Stellar Mass
Niu, Zexi; Liu, Jifeng; Yuan, Haibo +1 more
The metallicity dependence of the wide binary fraction (WBF) is critical for studying the formation of wide binaries. While controversial results have been found in recent years, here we combine the wide binary catalog recognized from Gaia EDR3 and stellar parameters from LAMOST to investigate this topic. Taking the bias of the stellar temperature…
Dependence of Pulsation Mode of Cepheids on Metallicity
Ren, Yi; Wang, Shu; Jiang, Biwei +2 more
The Cepheid variables in the Small Magellanic Cloud (SMC), the Large Magellanic Cloud (LMC), the Milky Way, M33, and M31 are used to examine the dependence of pulsation mode on metallicity, which was previously found in red supergiants. The initial samples of Cepheids are collected from the Cepheid catalogs identified from the Optical Gravitationa…
Scattered Light in the Hinode/EIS and SDO/AIA Instruments Measured from the 2012 Venus Transit
Young, Peter R.; Viall, Nicholeen M.
Observations from the 2012 transit of Venus are used to derive empirical formulae for long- and short-range scattered light at locations on the solar disk observed by the Hinode Extreme ultraviolet Imaging Spectrometer (EIS) and the Solar Dynamics Observatory Atmospheric Imaging Assembly (AIA) instruments. Long-range scattered light comes from the…
X-Ray Spectroscopic Evidence of Charge Exchange Emission in the Disk of M51
Wang, Q. Daniel; Zhang, Shuinai; Sun, Wei +3 more
In the disks of spiral galaxies, diffuse soft X-ray emission is known to be strongly correlated with star-forming regions. However, this emission is not simply from a thermal-equilibrium plasma and its origin remains greatly unclear. In this work, we present an X-ray spectroscopic analysis of the emission from the northern hot spot; a region with …
Gaia GraL: Gaia DR2 Gravitational Lens Systems. VII. XMM-Newton Observations of Lensed Quasars
Djorgovski, S. G.; Connor, Thomas; Walton, Dominic J. +23 more
We present XMM-Newton X-ray observations of nine confirmed lensed quasars at 1 ≲ z ≲ 3 identified by the Gaia Gravitational Lens program. Eight systems are strongly detected, with 0.3-8.0 keV fluxes F 0.3-8.0 ≳ 5 ×10-14 erg cm-2 s-1. Modeling the X-ray spectra with an absorbed power law, we derive power-…
Lithium Detection in Red Supergiant Stars of the Perseus Complex
Dalessandro, E.; Sanna, N.; Mucciarelli, A. +3 more
We present the first systematic study of lithium abundance in a chemically homogeneous sample of 27 red supergiants (RSGs) in the young Perseus complex. For these stars, accurate stellar parameters and detailed chemical abundances of iron and iron peak, CNO, alpha, light, and neutron capture elements have already been obtained by means of high-res…
Hubble Space Telescope Reveals Spectacular Light Echoes Associated with the Stripped-envelope Supernova 2016adj in the Iconic Dust Lane of Centaurus A
Patat, F.; Fraser, Morgan; Taddia, Francesco +6 more
We present a multiband sequence of Hubble Space Telescope images documenting the emergence and evolution of multiple light echoes (LEs) linked to the stripped-envelope supernova (SN) 2016adj located in the central dust lane of Centaurus A. Following point-spread function subtraction, we identify the earliest LE emission associated with an SN at on…
X-Ray Imaging Observations of the High-mass γ-Ray Binary HESS J0632+057
Kargaltsev, O.; Klingler, N. J.; Hare, J. +1 more
The Chandra X-Ray Observatory (CXO) imaged the high-mass γ-ray binary HESS J0632+057 with the Advanced CCD Imaging Spectrometer (ACIS). We analyzed the CXO data together with 967 ks of archival Swift-XRT observations. On arcsecond scales we find a hint of asymmetric extended emission. On arcminute scales, a region of extended emission ("the blob")…
K-band Imaging of the Nearby Clumpy, Turbulent Disk Galaxy DYNAMO G04-1
Glazebrook, Karl; Fisher, Deanne B.; Obreschkow, Danail +2 more
We present a case study of the stellar clumps in G04-1-a clumpy, turbulent disk galaxy located at z = 0.13-from the DYnamics of Newly-Assembled Massive Objects sample, using adaptive optics-enabled K-band imaging (~2.25 kpc arcsec-1) with Keck-NIRC2. We identify 15 stellar clumps in G04-1 with a range of masses from 3.6 × 106…
A Tale of Three Dust Populations: Variable R V and Extreme Polarization along Sight Lines toward ζ Ophiuchi
Piccone, Ashley N.; Kobulnicky, Henry A.
Dust permeates the interstellar medium, reddening and polarizing background starlight, but dust properties vary with local environment. In order to characterize dust in a highly irradiated diffuse cloud, we measure the reddening and optical polarization toward 27 stars surrounding the midlatitude b = +24° O9.2IV star ζ Ophiuchi, using new optical …