6,110 research outputs found
Jet Charge at the LHC
Knowing the charge of the parton initiating a light-quark jet could be
extremely useful both for testing aspects of the Standard Model and for
characterizing potential beyond-the-Standard-Model signals. We show that
despite the complications of hadronization and out-of-jet radiation such as
pile-up, a weighted sum of the charges of a jet's constituents can be used at
the LHC to distinguish among jets with different charges. Potential
applications include measuring electroweak quantum numbers of hadronically
decaying resonances or supersymmetric particles, as well as Standard Model
tests, such as jet charge in dijet events or in hadronically-decaying W bosons
in t-tbar events. We develop a systematically improvable method to calculate
moments of these charge distributions by combining multi-hadron fragmentation
functions with perturbative jet functions and pertubative evolution equations.
We show that the dependence on energy and jet size for the average and width of
the jet charge can be calculated despite the large experimental uncertainty on
fragmentation functions. These calculations can provide a validation tool for
data independent of Monte-Carlo fragmentation models.Comment: 5 pages, 6 figures; v2 published versio
On Statistical Aspects of Qjets
The process by which jet algorithms construct jets and subjets is inherently
ambiguous and equally well motivated algorithms often return very different
answers. The Qjets procedure was introduced by the authors to account for this
ambiguity by considering many reconstructions of a jet at once, allowing one to
assign a weight to each interpretation of the jet. Employing these weighted
interpretations leads to an improvement in the statistical stability of many
measurements. Here we explore in detail the statistical properties of these
sets of weighted measurements and demonstrate how they can be used to improve
the reach of jet-based studies.Comment: 29 pages, 6 figures. References added, minor modification of the
text. This version to appear in JHE
Applying the concepts of consumption emotions to tourism
poster abstractResearch has highlighted the natural relationship between tourism and the concepts of hedonic experiences and experiential consumption. Understanding the emotional response to an experience can help marketers highlight important aspects of the satisfaction judgment which can lead to repurchase/revisitation behavior. This study started with Richins’ (1997) Consumption Emotion Set (CES) which contains 43 “emotion words” describing feelings experienced during a consumption experience that represent 13 proposed discrete emotions. Confirmatory Factor Analysis was conducted to reduce the set to 25 emotion descriptors that loaded into 12 emotions; peaceful, calm, optimistic, pleased, excited, discontent, worried, sad, fear, shame, envy and loneliness. While researchers continue to seek a universal set of discrete emotions, limitations are inherent with differences in context, culture, and type of consumption. The findings of this study highlight the importance of adjusting the scale to the study context. For example, this study found the emotion of “romantic love” found in the original CES as inappropriate to research in golf tourism. Follow up interviews showed that most participants in this context engage in the sport with same-gendered friends. However, if the CES was applied in a sport tourism context where couples participate, romantic love could be experienced at a significant level. Additionally, the results of this study could be different due to the immediate response to the emotion scale. Future studies should further investigate this potential as well as test scales of discrete emotions in other contexts
Qjets: A Non-Deterministic Approach to Tree-Based Jet Substructure
Jet substructure is typically studied using clustering algorithms, such as
kT, which arrange the jets' constituents into trees. Instead of considering a
single tree per jet, we propose that multiple trees should be considered,
weighted by an appropriate metric. Then each jet in each event produces a
distribution for an observable, rather than a single value. Advantages of this
approach include: 1) observables have significantly increased statistical
stability; and, 2) new observables, such as the variance of the distribution,
provide new handles for signal and background discrimination. For example, we
find that employing a set of trees substantially reduces the observed
fluctuations in the pruned mass distribution, enhancing the likelihood of new
particle discovery for a given integrated luminosity. Furthermore, the
resulting pruned mass distributions for (background) QCD jets are found to be
substantially wider than that for (signal) jets with intrinsic mass scales,
e.g. jets containing a W decay. A cut on this width yields a substantial
enhancement in significance relative to a cut on the standard pruned jet mass
alone. In particular the luminosity needed for a given significance requirement
decreases by a factor of two relative to standard pruning.Comment: Minor changes to match journal versio
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Applying the Consumption Emotions Set to sport tourism
Research has highlighted the natural relationship between tourism and the concepts of hedonic experiences and experiential consumption. Understanding the emotional response to an experience can help marketers highlight important aspects of the satisfaction judgment. The purpose of this paper was to test the Consumption Emotions Set developed by Richins to verify its applicability in a sport tourism context. Results from confirmatory factor analysis indicate that while the scale has promise, it is important to adjust the scale to the context. Not all experiences evoke the full range of consumption emotions as presented by Richins
Relation of lineaments to sulfide deposits: Bald Eagle Mountain, Centre County, Pennsylvania
The author has identified the following significant results. Discrete areas of finely-fractured and brecciated sandstone float are present along the crest of Bald Mountain and are commonly sites of sulfide mineralization, as evidenced by the presence of barite and limonite gossans. The frequency distributions of the brecciated float as the negative binomial distribution supports the interpretation of a separate population of intensely fractured material. Such zones of concentrated breccia float have an average width of one kilometer with a range from 0.4 to 1.6 kilometers and were observed in a quarry face to have subvertical dips. Direct spatial correlation of the Landsat-derived lineaments to the fractured areas on the ridge is low; however, the mineralized and fracture zones are commonly assymetrical to the lineament positions. Such a systematic dislocation might result from an inherent bias in the float population or could be the product of the relative erosional resistance of the silicified material in the mineralized areas in relation to the erosionally weak material at the stream gaps
Long-term corrosion evaluation of stainless steels in Space Shuttle iodinated resin and water
The effects of stainless steel exposure to iodinated water is a concern in developing the Integrated Water System (IWS) for Space Station Freedom. The IWS has a life requirement of 30 years, but the effects of general and localized corrosion over such a long period have not been determined for the candidate materials. In 1978, Umpqua Research Center immersed stainless steel 316L, 321, and 347 specimens in a solution of deionized water and the Space Shuttle microbial check valve resin. In April 1990, the solution was chemically analyzed to determine the level of corrosion formed, and the surface of each specimen was examined with scanning electron microscopy and metallography to determine the extent of general and pitting corrosion. This examination showed that the attack on the stainless steels was negligible and never penetrated past the first grain boundary layer. Of the three alloys, 316L performed the best; however, all three materials proved to be compatible with an aqueous iodine environment. In addition to the specimens exposed to aqueous iodine, a stainless steel specimen (unspecified alloy) was exposed to moist microbial check valve resin and air for a comparable period. This environment allowed contact of the metal to the resin as well as to the iodine vapor. Since the particular stainless steel alloy was not known, energy dispersive spectroscopy was used to determine that this alloy was stainless steel 301. The intergranular corrosion found on the specimen was limited to the first grain boundary layer
A Study of Psychological Support from Local Residents for Hosting Mega-Sporting Events: A Case of the 2012 Indianapolis Super Bowl XLVI
The purpose of the current study was to assess local residents' psychological support prior to hosting a mega-sporting event and to report preliminary results as to which factors of support affect local residents' attitudes toward hosting future mega-sporting events, using the case of the 2012 Super Bowl in Indianapolis. This study provides a theoretical model to examine local residents' psychological support factors using structural equation modeling, which helps the understanding of local residents in the process of supporting the hosting of mega-sporting events in the future. The results of this study indicate that the perceptions of positive outcomes from the event have the strongest relationship to feelings toward hosting future events. Therefore, governing bodies of the host community and the event should rely most heavily on the positive outcomes. While the negative factors were not as strongly related, they were still significant indicators of feelings toward future events. The part of the plans pertaining to growing community support should include ways that the negative impacts might be mitigated
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