Search Publications
Collisions of Terrestrial Worlds: The Occurrence of Extreme Mid-infrared Excesses around Low-mass Field Stars
Theissen, Christopher A.; West, Andrew A.
We present the results of an investigation into the occurrence and properties (stellar age and mass trends) of low-mass field stars exhibiting extreme mid-infrared (MIR) excesses ({L}{IR}/{L}* ≳ 0.01). Stars for the analysis were initially selected from the Motion Verified Red Stars (MoVeRS) catalog of photometric stars with …
ASASSN-16eg: New candidate for a long-period WZ Sge-type dwarf nova
Nogami, Daisaku; Kato, Taichi; Isogai, Keisuke +19 more
We report on our photometric observations of the 2016 superoutburst of ASASSN-16eg. This object showed a WZ Sge-type superoutburst with prominent early superhumps with a period of 0.075478(8) d and a post-superoutburst rebrightening. During the superoutburst plateau, it showed ordinary superhumps with a period of 0.077880(3) d and a period derivat…
Exploring the SDSS Data Set with Linked Scatter Plots. I. EMP, CEMP, and CV Stars
Carbon, Duane F.; Henze, Christopher; Nelson, Bron C.
We present the results of a search for extremely metal-poor (EMP), carbon-enhanced metal-poor (CEMP), and cataclysmic variable (CV) stars using a new exploration tool based on linked scatter plots (LSPs). Our approach is especially designed to work with very large spectrum data sets such as the SDSS, LAMOST, RAVE, and Gaia data sets, and it can be…
Photospheric Velocity Structures during the Emergence of Small Active Regions on the Sun
Toriumi, Shin; Khlystova, Anna
We study the plasma flows in the solar photosphere during the emergence of two small active regions, NOAA 9021 and 10768. Using Solar and Heliospheric Observatory/Michelson Doppler Imager data, we find that the strong plasma upflows appear at the initial stage of active region formation, with maximum upflow velocities of -1650 and -1320 m s-1…
Low-ℓ CMB from string-scale SUSY breaking?
Sagnotti, A.
Models of inflation are instructive playgrounds for supersymmetry (SUSY) breaking in Supergravity and String Theory. In particular, combinations of branes and orientifolds that are not mutually BPS can lead to brane SUSY breaking, a phenomenon where nonlinear realizations are accompanied, in tachyon-free vacua, by the emergence of steep exponentia…
Searching for initial stage of massive star formation around the H II region G18.2-0.3
Zhang, Chuan-Peng; Wang, Jun-Jie; Yuan, Jing-Hua +6 more
Sometimes, early star formation can be found in cold and dense molecular clouds, such as an infrared dark cloud. Considering that star formation often occurs in clusters, H II regions may be triggering a new generation of star formation, so we can search for the initial stage of massive star formation around H II regions. Based on the above, this …
A hierarchical model for the ages of Galactic halo white dwarfs
Si, Shijing; van Dyk, David A.; von Hippel, Ted +3 more
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. In this paper, we develop novel methods that allow us to take advantage of existing software designed for such case-by-case analyses to simultaneously fit parameters of b…
Herschel/SPIRE observations of water production rates and ortho-to-para ratios in comets★
Swinyard, Bruce M.; Wilson, Thomas G.; Rawlings, Jonathan M. C.
This paper presents Herschel/SPIRE (Spectral and Photometric Imaging Receiver) spectroscopic observations of several fundamental rotational ortho- and para-water transitions seen in three Jupiter-family comets and one Oort-cloud comet. Radiative transfer models that include excitation by collisions with neutrals and electrons, and by solar infrare…
The NGC 454 system: anatomy of a mixed ongoing merger
Plana, H.; Marino, A.; Mazzei, P. +3 more
This paper focuses on NGC 454, a nearby interacting pair of galaxies (AM 0112-554, RR23), composed of an early-type (NGC 454 E) and a star-forming late-type companion (NGC 454 W). We aim at characterizing this wet merger candidate via a multi-λ analysis, from near-UV (NUV) to optical using Swift UV/Optical Telescope (UVOT), and mapping the H α int…
The Spiral Arm Segments of the Galaxy within 3 kpc from the Sun: A Statistical Approach
Hou, Li-Gang; Jiang, Ing-Guey; Griv, Evgeny
As can be reasonably expected, upcoming large-scale APOGEE, GAIA, GALAH, LAMOST, and WEAVE stellar spectroscopic surveys will yield rather noisy Galactic distributions of stars. In view of the possibility of employing these surveys, our aim is to present a statistical method to extract information about the spiral structure of the Galaxy from curr…