982 research outputs found
Using Fan Passion to Investigate Constraints to Student Attendance at College Football Games
Given the decline in average student attendance at college football games nationwide, it is important for marketers to understand the constraints inhibiting student attendance. The current study addresses this issue by testing for differences in constraints affecting student nonattendance decisions based on their passion for the home team. Data were collected from students not attending games on six college campuses during actual football games. A total of 33 potential constraints to attendance were assessed. Results indicated statistically significant differences among intrapersonal, event-specific, and marketing-related constraints. Regardless of passion level, prior commitments to school and work were among the most highly-rated constraints to attendance. For highly-passionate fans, beverage costs, poor team performance, and watching the game on television were also highly-rated constraints. Low-passion fans, however, were constrained by time commitment necessary to attend, as well as lack of interest in football
Kepler Observations of Three Pre-Launch Exoplanet Candidates: Discovery of Two Eclipsing Binaries and a New Exoplanet
Three transiting exoplanet candidate stars were discovered in a ground-based
photometric survey prior to the launch of NASA's {\it Kepler} mission. {\it
Kepler} observations of them were obtained during Quarter 1 of the {\it Kepler}
mission. All three stars are faint by radial velocity follow-up standards, so
we have examined these candidates with regard to eliminating false positives
and providing high confidence exoplanet selection. We present a first attempt
to exclude false positives for this set of faint stars without high resolution
radial velocity analysis. This method of exoplanet confirmation will form a
large part of the {\it Kepler} mission follow-up for Jupiter-sized exoplanet
candidates orbiting faint stars. Using the {\it Kepler} light curves and pixel
data, as well as medium resolution reconnaissance spectroscopy and speckle
imaging, we find that two of our candidates are binary stars. One consists of a
late-F star with an early M companion while the other is a K0 star plus a late
M-dwarf/brown dwarf in a 19-day elliptical orbit. The third candidate (BOKS-1)
is a =15 G8V star hosting a newly discovered exoplanet with a radius of 1.12
R in a 3.9 day orbit.Comment: Accepted for publication in The Astrophysical Journa
Kepler Observations of the Three Pre-Launch Exoplanet Candidates: Discover of Two Eclipsing Binaries and a New Exoplanet
Three transiting exoplanet candidate stars were discovered in a ground-based photometric survey prior to the launch of NASA's Kepler mission. Kepler observations of them were obtained during Quarter 1 of the Kepler mission. All three stars are faint by radial velocity follow-up standards, so we have examined these candidates with regard to eliminating false positives and providing high confidence exoplanet selection. We present a first attempt to exclude false positives for this set of faint stars without high-resolution radial velocity analysis. This method of exoplanet confirmation will form a large part of the Kepler mission follow-up for Jupiter-sized exoplanet candidates orbiting faint stars. Using the Kepler light curves and pixel data, as well as medium-resolution reconnaissance spectroscopy and speckle imaging, we find that two of our candidates are binary stars. One consists of a late-F star with an early M companion, while the other is a K0 star plus a late M-dwarf/brown dwarf in a 19 day elliptical orbit. The third candidate (BOKS-1) is an r = 15 G8V star hosting a newly discovered exoplanet with a radius of 1.12 R_(Jupiter) in a 3.9 day orbit
Quantifying Stellar Mass Loss with High Angular Resolution Imaging
Mass is constantly being recycled in the universe. One of the most powerful
recycling paths is via stellar mass-loss. All stars exhibit mass loss with
rates ranging from ~10(-14) to 10(-4) M(sun) yr-1, depending on spectral type,
luminosity class, rotation rate, companion proximity, and evolutionary stage.
The first generation of stars consisted mostly of hydrogen and helium. These
shed material - via massive winds, planetary nebulae and supernova explosions -
seeding the interstellar medium with heavier elements. Subsequent generations
of stars incorporated this material, changing how stars burn and providing
material for planet formation. An understanding of mass loss is critical for
modeling individual stars as well as answering larger astrophysical questions.
Understanding mass loss is essential for following the evolution of single
stars, binaries, star clusters, and galaxies. Mass loss is one of our weakest
areas in the modeling of fundamental stellar processes. In large part this is
owing to lack of confrontation with detailed observations of stellar
photospheres and the mass-loss process. High resolution optical imagery with
telescope arrays is beginning to provide these data and, combined with
spectroscopy and broad infrared and sub-mm coverage, supporting more
sophisticated models on fast computers and promising a new era in mass-loss
studies.Comment: Science white paper prepared for Astro201
The FUV to Near-IR Morphologies of Luminous Infrared Galaxies in the GOALS Sample
We compare the morphologies of a sample of 20 LIRGs from the Great
Observatories All-sky LIRG Survey (GOALS) in the FUV, B, I and H bands, using
the Gini (G) and M20 parameters to quantitatively estimate the distribution and
concentration of flux as a function of wavelength. HST images provide an
average spatial resolution of ~80 pc. While our LIRGs can be reliably
classified as mergers across the entire range of wavelengths studied here,
there is a clear shift toward more negative M20 (more bulge-dominated) and a
less significant decrease in G values at longer wavelengths. We find no
correlation between the derived FUV G-M20 parameters and the global measures of
the IR to FUV flux ratio, IRX. Given the fine resolution in our HST data, this
suggests either that the UV morphology and IRX are correlated on very small
scales, or that the regions emitting the bulk of the IR emission emit almost no
FUV light. We use our multi-wavelength data to simulate how merging LIRGs would
appear from z~0.5-3 in deep optical and near-infrared images such as the HUDF,
and use these simulations to measure the G-M20 at these redshifts. Our
simulations indicate a noticeable decrease in G, which flattens at z >= 2 by as
much as 40%, resulting in mis-classifying our LIRGs as disk-like, even in the
rest-frame FUV. The higher redshift values of M20 for the GOALS sources do not
appear to change more than about 10% from the values at z~0. The change in
G-M20 is caused by the surface brightness dimming of extended tidal features
and asymmetries, and also the decreased spatial resolution which reduced the
number of individual clumps identified. This effect, seen as early as z~0.5,
could easily lead to an underestimate of the number of merging galaxies at
high-redshift in the rest-frame FUV.Comment: Accepted for publication in the Astronomical Journal. The total page
count is 15 pages with 13 figures and 1 Tabl
The Spatial Extent of (U)LIRGs in the Mid-Infrared. II. Feature Emission
We present results from the second part of our analysis of the extended
mid-infrared (MIR) emission of the Great Observatories All-Sky LIRG Survey
(GOALS) sample based on 5-14 micron low-resolution spectra obtained with the
IRS on Spitzer. We calculate the fraction of extended emission as a function of
wavelength for all galaxies in the sample, FEE_lambda, and spatially separate
the MIR spectrum of galaxies into their nuclear and extended components.
We find that the [NeII] emission line is as compact as the hot dust MIR
continuum, while the polycyclic aromatic hydrocarbon (PAH) emission is more
extended. The 6.2 and 7.7 micron PAH emission is more compact than that of the
11.3 micron PAH, which is consistent with the formers being enhanced in a more
ionized medium. The presence of an AGN or a powerful nuclear starburst
increases the compactness of the hot dust MIR continuum, but has a negligible
effect on the spatial extent of the PAH emission on kpc-scales. Globally, the
spectra of the extended emission component are homogeneous for all galaxies in
GOALS. This suggests that the physical properties of star formation taking
place at distances farther than 1.5 kpc from the nuclei of (U)LIRGs are very
similar, resembling local star-forming galaxies with L_IR < 10^11 Lsun, as well
as star formation-dominated ULIRGs at z~2. In contrast, the MIR spectra of the
nuclear component of local (U)LIRGs are very diverse. This implies that the
observed variety of their integrated MIR properties arise, on average, only
from the processes that are taking place in their cores.Comment: 16 pages, 7 figures, accepted for publication in Ap
A Class of Eccentric Binaries with Dynamic Tidal Distortions Discovered with Kepler
We have discovered a class of eccentric binary systems within the Kepler data
archive that have dynamic tidal distortions and tidally-induced pulsations.
Each has a uniquely shaped light curve that is characterized by periodic
brightening or variability at time scales of 4-20 days, frequently accompanied
by shorter period oscillations. We can explain the dominant features of the
entire class with orbitally-varying tidal forces that occur in close, eccentric
binary systems. The large variety of light curve shapes arises from viewing
systems at different angles. This hypothesis is supported by spectroscopic
radial velocity measurements for five systems, each showing evidence of being
in an eccentric binary system. Prior to the discovery of these 17 new systems,
only four stars, where KOI-54 is the best example, were known to have evidence
of these dynamic tides and tidally-induced oscillations. We perform preliminary
fits to the light curves and radial velocity data, present the overall
properties of this class and discuss the work required to accurately model
these systems.Comment: 13 pages, submitted to Ap
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