2,026 research outputs found
Identified particle transverse momentum distributions from AU + AU collisions at 62.4 GeV per nucleon pair
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2005.Vita.Includes bibliographical references (leaves 137-147).Transverse momentum (PT) distributions for pions, kaons, protons and antiprotons have been measured near mid-rapidity for Au+Au collisions at sNN = 62.4 GeV using the PHOBOS detector at the Relativistic Heavy-Ion Collider (RHIC) in Brookhaven National Laboratory. Particle identification is performed using the PHOBOS Time-of-Flight plastic scintillator walls and specific energy loss in the multi-layer silicon Spectrometer, which is also used for track reconstruction and momentum-determination. The spectra are corrected for all detector-dependent effects, including feed-down from weak decays. At PT 3 GeV/c, protons are measured to be the dominant species of charged hadrons and scale much faster with respect to collision centrality than mesons. This behaviour at 62.4 GeV is found to be remarkably similar to that observed in Au+Au collisions at 200 GeV, an interesting observation which should serve as an important constraint on the various mechanisms which have been proposed to describe particle production over this PT range. Baryon stopping, the transport of baryon number from intial beam rapidity, is explored through the net proton (p - p) yields at mid-rapidity. These results fill a large gap between the SPS and higher RHIC energies and as such form an important set of data for comparing to models of baryon transport mechanisms.by Conor Henderson.Ph.D
The long reach of sponsorship: How fan isolation and identification jointly shape sponsorship performance
© American Marketing Association 2018. Globalization and technology have expanded the reach of sports teams, giving brand sponsors new opportunities to engage and build relationships in real time with fans outside a teamâs home market. This research investigates the role of fan isolation, or the experience of feeling separated from the team community, in shaping sponsorship effectiveness. The authors posit that such isolation increases the desire to affiliate with the team community, which can increase preferences for team-linked brands. However, the effect of isolation on sponsor performance depends on the strength of fan identification. Isolation increases strong fansâ desire to affiliate with the team community, thereby enhancing sponsorship performance; by contrast, isolation causes weak fans to avoid team-linked brands. Two field studies and four quasi experiments conducted across three countries (N = 1,412) confirm these predictions. Isolated strong fans exhibit increased recall, attitudes, purchase intentions, and word of mouth for sponsors, while isolated weak fans display the opposite effects. For brand managers, the proposed framework reveals whether isolated fans provide the best or worst returns on their sponsorships
Easy as 4-AT: Improving Delirium Screening in Acute Elderly Admissions with a Targeted Educational Intervention
Peer reviewedPublisher PD
The color of support: The effect of sponsorâteam visual congruence on sponsorship performance
© American Marketing Association 2019. Brand sponsorship connects brands with large, passionate audiences. The sponsorship literature emphasizes the importance of brand sponsorâteam congruence; however, prior research has largely focused on the relevance of the brand to the sport or geographic area. This article offers the first real-world empirical investigation of the effects of visual congruence through color matching on sponsorship performance. A wide-scale study of 703 Major League Baseball fansâ evaluations of their teamâs sponsors, merged with real stadium signage data, offers evidence of the benefits of visual congruence. Two experiments in the contexts of product packaging and online advertising provide converging evidence of the positive effects of created visual congruence on attitudes toward the sponsorship, brand attitudes, and intentions. Brands without an inherent match to a team can enjoy enhanced sponsorship benefits with little additional costs simply by adopting the teamâs colors in visual displays. However, the viewerâs motivation (fan status), opportunity (fan exposure), and ability (lack of color blindness) to process visual congruence moderates its effectiveness. By using the proposed framework, managers can maximize the value of their sponsorship rights
Measurement of the Top-Quark Mass with Dilepton Events Selected Using Neuroevolution at CDF
We report a measurement of the top-quark mass Mt in the dilepton decay channel ttÌâblâČ+ÎœlâČbÌl-ÎœÌl. Events are selected with a neural network which has been directly optimized for statistical precision in top-quark mass using neuroevolution, a technique modeled on biological evolution. The top-quark mass is extracted from per-event probability densities that are formed by the convolution of leading order matrix elements and detector resolution functions. The joint probability is the product of the probability densities from 344 candidate events in 2.0fb-1 of ppÌ collisions collected with the CDF II detector, yielding a measurement of Mt=171.2±2.7(stat)±2.9(syst)GeV/c2
Nucleon-Gold Collisions at 200 AGeV Using Tagged d+Au Interactions in PHOBOS
Forward calorimetry in the PHOBOS detector has been used to study charged
hadron production in d+Au, p+Au and n+Au collisions at sqrt(s_nn) = 200 GeV.
The forward proton calorimeter detectors are described and a procedure for
determining collision centrality with these detectors is detailed. The
deposition of energy by deuteron spectator nucleons in the forward calorimeters
is used to identify p+Au and n+Au collisions in the data. A weighted
combination of the yield of p+Au and n+Au is constructed to build a reference
for Au+Au collisions that better matches the isospin composition of the gold
nucleus. The p_T and centrality dependence of the yield of this improved
reference system is found to match that of d+Au. The shape of the charged
particle transverse momentum distribution is observed to extrapolate smoothly
from pbar+p to central d+Au as a function of the charged particle
pseudorapidity density. The asymmetry of positively- and negatively-charged
hadron production in p+Au is compared to that of n+Au. No significant asymmetry
is observed at mid-rapidity. These studies augment recent results from
experiments at the LHC and RHIC facilities to give a more complete description
of particle production in p+A and d+A collisions, essential for the
understanding the medium produced in high energy nucleus-nucleus collisions.Comment: 17 pages, 18 figure
Place, space, and foreign direct investment into peripheral cities
Perspectives drawn from the economic geography literature are increasingly used to generate insights into locational issues in international business. In this paper, we seek to integrate these literatures further by investigating the locational determinants of foreign direct investment (FDI) into peripheral cities within an emerging economy. Peripheral cities in emerging economies are attracting a growing proportion of global FDI flows, but the international business literature lacks a framework for understanding subnational determinants of FDI, particularly into non-core locations. We draw on the core-periphery model to build and test theory on how spatial interdependencies between subnational locations impact on the distribution of FDI inflows into a large and heterogeneous country China. Our results show that whilst peripheral cities tend to have a negative effect on FDI, this effect is positively moderated by proximity to core cities. The results highlight the importance of considering interactions between place and space when investigating locational issues in international business
Participant and spectator scaling of spectator fragments in Au + Au and Cu + Cu collisions at âsNN = 19.6 and 22.4 GeV
Spectator fragments resulting from relativistic heavy ion collisions, consisting of single protons and neutrons along with groups of stable nuclear fragments up to nitrogen (Z=7), are measured in PHOBOS. These fragments are observed in Au+Au (âsNN =19.6GeV) and Cu+Cu (22.4 GeV) collisions at high pseudorapidity (η). The dominant multiply-charged fragment is the tightly bound helium (α), with lithium, beryllium, and boron all clearly seen as a function of collision centrality and pseudorapidity. We observe that in Cu+Cu collisions, it becomes much more favorable for the α fragments to be released than lithium. The yields of fragments approximately scale with the number of spectator nucleons, independent of the colliding ion. The shapes of the pseudorapidity distributions of fragments indicate that the average deflection of the fragments away from the beam direction increases for more central collisions. A detailed comparison of the shapes for α and lithium fragments indicates that the centrality dependence of the deflections favors a scaling with the number of participants in the collision.United States. Department of Energy (Grant DE-AC02-98CH10886)United States. Department of Energy (Grant DE-FG02-93ER40802)United States. Department of Energy (Grant DE-FG02-94ER40818)United States. Department of Energy (Grant DE-FG02-94ER40865)United States. Department of Energy (Grant DE-FG02- 99ER41099)United States. Department of Energy (Grant DE-AC02-06CH11357)National Science Foundation (U.S.) (Grant 9603486)National Science Foundation (U.S.) (Grant 0072204)National Science Foundation (U.S.) (Grant 0245011
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