Search Publications
On the Radial Metallicity Gradient and Radial Migration Effect of the Galactic Disk
Zhao, Gang; Chen, Yuqin; Li, Chengdong +4 more
We study the radial metallicity gradient Δ[M/H]/ΔR g as a function of [Mg/Fe] and | Z| with the help of a guiding radius based on the Apache Point Observatory Galactic Evolution Experiment and Gaia and then analyze the radial migration effect on the radial metallicity gradient and metallicity-rotation gradient between the Galactic thi…
Magnetic Field Uniformity Across the GF 9-2 YSO, L1082C Dense Core, and GF 9 Filamentary Dark Cloud
Pillai, T.; Cerny, C.; Clemens, Dan P. +3 more
The orientation of the magnetic field (B field) in the filamentary dark cloud GF 9 was traced from the periphery of the cloud into the L1082C dense core that contains the low-mass, low-luminosity Class 0 young stellar object (YSO) GF 9-2 (IRAS 20503+6006). This was done using SOFIA HAWC+ dust thermal emission polarimetry (TEP) at 216 µm in c…
The JCMT Gould Belt Survey: A First Look at the Auriga-California Molecular Cloud with SCUBA-2
White, G. J.; Wilson, C. D.; Di Francesco, J. +57 more
We present 850 and 450 µm observations of the dense regions within the Auriga-California molecular cloud using SCUBA-2 as part of the JCMT Gould Belt Legacy Survey to identify candidate protostellar objects, measure the masses of their circumstellar material (disk and envelope), and compare the star formation to that in the Orion A molecular…
Disturbed Fossil Group Galaxy NGC 1132
Trinchieri, Ginevra; Fabbiano, Giuseppina; O'Sullivan, Ewan +10 more
We have analyzed the Chandra archival data of NGC 1132, a well-known fossil group, i.e., a system expected to be old and relaxed long after the giant elliptical galaxy assembly. Instead, the Chandra data reveal that the hot gas morphology is disturbed and asymmetrical, with a cold front following a possible bow shock. We discuss possible origins o…
Relativistic Astronomy
Zhang, Bing; Li, Kunyang
The “Breakthrough Starshot” aims at sending near-speed-of-light cameras to nearby stellar systems in the future. Due to the relativistic effects, a transrelativistic camera naturally serves as a spectrograph, a lens, and a wide-field camera. We demonstrate this through a simulation of the optical-band image of the nearby galaxy M51 in the rest fra…
The Direct Detection and Characterization of M-dwarf Planets Using Light Echoes
White, Richard L.; Sparks, William B.; Ford, Holland C. +1 more
Exoplanets orbiting M-dwarf stars are a prime target in the search for life in the universe. M-dwarf stars are active, with powerful flares that could adversely impact prospects for life, though there are counter-arguments. Here, we turn flaring to advantage and describe ways in which it can be used to enhance the detectability of planets, in the …
A Search for H I Lyα Counterparts to Ultrafast X-Ray Outflows
Kriss, Gerard A.; Lee, Julia C.; Danehkar, Ashkbiz
Prompted by the H I Lyα absorption associated with the X-ray ultrafast outflow at -17,300 km s-1 in the quasar PG 1211+143, we have searched archival UV spectra at the expected locations of H I Lyα absorption for a large sample of ultrafast outflows identified in XMM-Newton and Suzaku observations. Sixteen of the X-ray outflows have pre…
Does the Compact Radio Jet in PG 1700+518 Drive a Molecular Outflow?
Rupke, David S. N.; Gültekin, Kayhan; Runnoe, Jessie C.
Radio jets play an important role in quasar feedback, but direct observations showing how the jets interact with the multi-phase interstellar medium of galaxy disks are few and far between. In this work, we provide new millimeter interferometric observations of PG 1700+518 in order to investigate the effect of its radio jet on the surrounding mole…
Galaxy Ellipticity Measurements in the Near-infrared for Weak Lensing
Wright, Edward L.; Chary, Ranga-Ram; Lee, Bomee
We investigate the value of the near-infrared imaging from upcoming surveys for constraining the ellipticities of galaxies. We select galaxies between 0.5 ≤ z < 3 that are brighter than expected Euclid sensitivity limits from the GOODS-S and N fields in CANDELS. The co-added CANDELS/HST V+I and J+H images are degraded in resolution and sensitiv…
Inner Source C+/O+ Pickup Ions Produced by Solar Wind Recycling, Neutralization, Backscattering, Sputtering, and Sputtering-induced Recycling
Möbius, E.; Schwadron, N. A.; Berger, L. +2 more
Inner source pickup ions (PUIs) are believed to be created by the interaction between the solar wind and interplanetary dust grains. The production mechanism, however, is not well understood. We use the Stopping Range of Ions in Matter and Energetic Particle Radiation Environment Module to simulate the production and transport of inner source C