11,012 research outputs found
Research study of droplet sizing technology leading to the development of an advanced droplet sizing system
An instrument to measure the size and velocity of droplets was developed. The instrument uses one of two techniques, as appropriate. In the first technique two small laser beams of one color identify the center of a larger laser beam of a different color. This defines a region of almost uniform intensity where the light scattered by the individual droplets can be related to their size. The first technique uses the visibility of a Doppler burst and validates it against the peak intensity of the signal's pedestal. Results are presented for monodisperse, bimodal, trimodal, and polydisperse sprays produced by the Berglund-Liu droplet generator and a pressure nozzle. Size distributions of a given spray obtained using three different size ranges show excellent self-consistency in the overlapping region. Measurements of sprays of known characteristics exhibit errors in the order of 10%. The principles of operation and design criteria of the instrument are discussed in great detail
The Higgs mass in the MSSM infrared fixed point scenario
In the infrared fixed point (IFP) scenario of the minimal supersymmetric
model (MSSM), the top-quark mass and other physical quantities of the
low-energy theory are insensitive to the values of the parameters of the theory
at some high energy scale. In this framework we evaluate the light CP-even
Higgs mass, , taking into account some important effects that had not been
previously considered. In particular, the supersymmetric correction to the
relation between the running and the physical top-quark masses lowers the value
of , thereby implying a lower predicted value of . Assuming a
supersymmetric threshold of TeV and GeV, we find an upper
bound of GeV; the most plausible value of lies somewhat
below the upper bound. This places the Higgs boson in the IFP scenario well
within the reach of the LEP-2 Higgs search.Comment: 18 pages, LaTeX, 5 ps figures, uses psfig.sty. Final version, some
comments and a figure added, references correcte
Renormalization of dimension-six operators relevant for the Higgs decays
The discovery of the Higgs boson has opened a new window to test the SM
through the measurements of its couplings. Of particular interest is the
measured Higgs coupling to photons which arises in the SM at the one-loop
level, and can then be significantly affected by new physics. We calculate the
one-loop renormalization of the dimension-six operators relevant for
, which can be potentially important since
it could, in principle, give log-enhanced contributions from operator mixing.
We find however that there is no mixing from any current-current operator that
could lead to this log-enhanced effect. We show how the right choice of
operator basis can make this calculation simple. We then conclude that
can only be affected by RG mixing from
operators whose Wilson coefficients are expected to be of one-loop size, among
them fermion dipole-moment operators which we have also included.Comment: 21 pages. Improved version with h -> gamma Z results added and
structure of anomalous-dimension matrix determined further. Conclusions
unchange
The Effect of Pack Size on Finish Time in the Fukuoka Marathon
Elite marathon runners have been pushing the limits of the human body, currently setting the world record near two hours. Notable factors while running include physiological, psychological, and strategic factors. Utilizing pack running may be a strategic factor to improve finish time and placement.
Purpose
To explore the effect of individuals running in various size packs on their place and finish time in the Fukuoka Marathon. This race has seen some of the most talented runners in history, as the world record has been broken twice at the Fukuoka Marathon, in 1967 and 1981.
Methods
The data set of results was received through a collaboration with Dr. Michael Joyner, of the Mayo Clinic. Subjects running in the Fukuoka Marathon in Fukuoka, Japan were all male (n=240). Marathon race times and splits was analyzed from the year 1967 through 2014. Race splits were recorded every five kilometers and at the halfway point. Only runners who finished in the top five were used to record pack sizes. Pack sizes were counted for every top five finisher at each split and a mean pack size was calculated. Finish times were normalized to the winning time of each race. One-way ANOVA test was performed to quantify the effect of mean pack size on finish time.
Results
No significant correlation was found between mean pack size and finish time for top five finishers (p=0.793). Regressions of mean pack size during the first half, second half, and entirety of the race yielded a slope of zero.
Conclusion
Although pack size and finish time were not significantly correlated, there were non- significant trends within the data that showed possible relation between place, size, and the duration of a pack that an individual ran with. Further studies should explore psychological benefits of racing in a pack, pack sizes outside of the top ten finishers, whether place within an individual pack is relevant to finish time, how individuals changing packs effects race dynamics, and if top finishers should be excluded from the pack pacing hypothesis
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