21,868 research outputs found
Dirac Gauginos in Supersymmetry -- Suppressed Jets + MET Signals: A Snowmass Whitepaper
We consider the modifications to squark production in the presence of a
naturally heavier Dirac gluino. First generation squark production is highly
suppressed, providing an interesting but challenging signal find or rule out.
No dedicated searches for supersymmetry with a Dirac gluino have been
performed, however a reinterpretation of a "decoupled gluino" simplified model
suggests the bounds on a common first and second generation squark mass is much
smaller than in the MSSM: \lsim 850 GeV for a massless LSP, and no bound for
an LSP heavier than about 300 GeV. We compare and contrast the squark
production cross sections between a model with a Dirac gluino and one with a
Majorana gluino, updating earlier results in the literature to a collider
operating at and 33 TeV. Associated production of squark+gluino
is likely very small at TeV, while is a challenging but
important signal at even higher energy colliders. Several other salient
implications of Dirac gauginos are mentioned, with some thought-provoking
discussion as it regards the importance of the various experiments planned or
proposed.Comment: 10 pages, 6 figures; this Snowmass Whitepaper has been submitted to
arXiv at the request of the Snowmass convener
Face masks for the public during Covid-19: an appeal for caution in policy
As the Covid-19 crisis deepens, some researchers have argued for the widespread routine use of face masks in community settings, despite acknowledged gaps in the evidence base for the effectiveness of such a measure. We argue that such calls are premature, and risk neglecting important potential harms and negative consequences, known and unknown. We identify potential unintended consequences at multiple levels, from individual-behavioural to macrosocial, and suggest that it is far from clear that the benefits of widespread uptake of face masks, whether encouraged or enforced by public authorities, outweigh the downsides. Finally, we make the case for caution in communicating unequivocal messages about the scientific evidence for face mask use to policy, practitioner and public audiences, given continued scientific disagreement on the questio
More than a Match: The Role of Football in Britain’s Deaf Community
The University of Central Lancashire has undertaken a major research project into the role of
football within the deaf community in Britain. As well as reconstructing the long history of deaf
involvement in football for the first time, the project has also focused on the way in which
football has provided deaf people with a means of developing and maintaining social contacts
within the community, and of expressing the community’s cultural values. This article will
draw on primary data gathered from interviews conducted with people involved in deaf football
in a variety of capacities. During the course of these interviews, a number of themes and issues
emerged relating to the values and benefits those involved with deaf football place on the game,
and it is these which are explored here
Shareholder Voting and Directors’ Remuneration Report Legislation: Say on Pay in the U.K. (CRI 2009-004)
This paper investigates shareholder voting in the UK. The Directors’ Remuneration Report (DRR) Regulations of 2002 gave shareholders a mandatory non-binding vote on boardroom pay. First, using data on about 50,000 resolutions over the period 2002 to 2007 we find that less than 10% of shareholders abstain or vote against the mandated Directors’ Remuneration Report (DRR) resolution. Second, investors are more likely to vote against DRR resolutions compared to non-pay resolutions. Third, shareholders are more likely to vote against general executive pay resolutions, such as stock options, long term incentive plans and bonus resolutions compared to non-pay resolutions. Forth, firms with higher CEO pay attract greater voting dissent. Fifth, there is little evidence that CEO pay is lower in firms that previously experienced high levels of shareholder dissent. In addition, there is little evidence that the equity pay-mix, representing better owner-manager alignment, is greater in such firms. Currently, we find limited evidence that, on average, ‘say on pay’ materially alters the subsequent level and design of CEO compensation
Natural Supersymmetry and Implications for Higgs physics
We re-analyze the LHC bounds on light third generation squarks in Natural
Supersymmetry, where the sparticles have masses inversely proportional to their
leading-log contributions to the electroweak symmetry breaking scale. Higgsinos
are the lightest supersymmetric particles; top and bottom squarks are the
next-to-lightest sparticles that decay into both neutral and charged Higgsinos
with well-defined branching ratios determined by Yukawa couplings and
kinematics. The Higgsinos are nearly degenerate in mass, once the bino and wino
masses are taken to their natural (heavy) values. We consider three scenarios
for the stop and sbottom masses: (I) is light, (II)
and are light, and (III) , , and
are light. Dedicated stop searches are currently sensitive to
Scenarios II and III, but not Scenario I. Sbottom-motivated searches () impact both squark flavors due to \tilde{t} \ra b \charp_1 as well
as \tilde{b} \ra b \neut_{1,2}, constraining Scenarios I and III with
somewhat weaker constraints on Scenario II. The totality of these searches
yield relatively strong constraints on Natural Supersymmetry. Two regions that
remain are: (1) the "compressed wedge", where , and (2) the "kinematic limit" region, where
m_{\tilde{q}} \gsim 600-750 GeV, at the kinematic limit of the LHC searches.
We calculate the correlated predictions for Higgs physics, demonstrating that
these regions lead to distinct predictions for the lightest Higgs couplings
that are separable with \simeq 10% measurements. We show that these
conclusions remain largely unchanged once the MSSM is extended to the NMSSM in
order to naturally obtain a large enough mass for the lightest Higgs boson
consistent with LHC data.Comment: 18 pages, 8 figure
A Mobile App Delivering a Gamified Battery of Cognitive Tests Designed for Repeated Play (OU Brainwave): App Design and Cohort Study
Background: Mobile phone and tablet apps are an increasingly common platform to collect data. A key challenge for researchers has been participant “buy-in” and participant attrition for designs requiring repeated testing.
Objective: The objective of this study was to develop and asses the utility of 1 – 2 minute versions of both classic and novel cognitive tasks within a user focussed and driven mobile phone and tablet app designed to encourage repeated play.
Methods: A large sample (N = 13,979 at first data collection) participated in multiple, self-paced, sessions of working memory (N-back), spatial cognition (Mental rotation), sustained attentional focus (Persistent Vigilance task), and split attention (Multiple object tracking) tasks along with an implementation of a novel action learning task. A full morningness-eveningness questionnaire was also included. Data was collected across an 18 month period. While the app prompted reengagement at set intervals, each participant was free to repeatedly complete each task as many times as they wished.
Results: We found a significant relationship between morningness and age (r = 0.298, n = 12755, p
Conclusions: Using extremely short testing periods and permitting participants to decide their own level of engagement - both in terms of which gamified task they played, and how many sessions they completed - we were able to collect a substantial and valid dataset. We suggest that the success of OU brainwave should inform future research oriented apps - particularly in issues around balancing participant engagement with data fidelity
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