2,125 research outputs found
The Raman Spectra of CH3CF3 and CCl2CF2
Because of the interest attached to ethane and ethane-like molecules in connection with the question of free rotation of the CX3 groups with respect to each other, it was considered that the Raman spectrum of CH3CF3 might yield additional information on this point. Inasmuch as the spectrum of the liquid can be conveniently photographed only at low temperatures (b.p. about -40°), the determination of the polarization of the scattered light would be experimentally very difficult and was not attempted. The fact that the frequencies associated with the CF3 group will be considerably different in magnitude from those of the CH3 group may, in the analysis, compensate for the lack of data on polarization. Only the results of the experiments are presented here; the assignment of the frequencies will be given when completed. The Raman spectrum of the ethylene-like molecule CCl2=CF2 was photographed at room temperature with the substance in the liquid state, and the observed shifts are presented here
QED X QCD Exponentiation: Shower/ME Matching and IR-Improved DGLAP Theory at the LHC
We discuss the elements of QED X QCD exponentiation and its interplay with
shower/ME matching and IR-improved DGLAP theory in precision LHC physics
scenarios. Applications to single heavy gauge boson production at hadron
colliders are illustrated.Comment: 5 pages, 1 figure; presented by B.F.L. Ward at ICHEP0
Precision Electro-Weak and Hadronic Luminosity Calculations
We have used YFS Monte Carlo techniques to obtain per-mil level accuracy for
the Bhabha scattering cross section used in the luminosity monitor in
electro-weak scattering experiments. We will describe techniques for extending
these methods for use in the W production luminosity cross section for hadron
colliders.Comment: 8 pages (LaTex) with 5 figures (EPS). Presented by S.A. Yost at the
Third International Symposium on Quantum Theory and Symmetries, Cincinnati,
Sept. 10 - 14, 200
Adolescent Leisure-Time Activity and Problem Behavior: The Integration of Three Major Explanatory Theories as a New
Adolescence has in recent decades gained attention as being salient for study of social trends. Increases in youth social problems are seen nationally, statewide, and locally. They include substance abuse, precocious sexual activity, related consequences of pregnancy and STDs, suicide and depression, truancy, running away, crime against property, and violent crime against persons.
This study integrates three major explanatory theories of adolescent behavior into a macro-synthesis. R. Jesser\u27s Problem Behavior Theory emphasizes how problem behaviors do not occur singularly, nor do they justify unique prevention methods. T. Hirschi\u27s Social Control Theory describes how adolescents with little or no attachment to their community are more likely to be involved in unconventional behaviors. E . Werner\u27s Resilience framework relates adult support and mentoring in childhood and adolescence with lower risk of problems later in life.
This study examines how one element of this synthesis, adolescents\u27 social environment, relates with social problems, or more specifically, how adolescent use of leisure time relates to problem behavior. A stratified random sample of 450 mail-out questionnaires yielded a 40% (181) response rate. Factor analysis placed 27 of 28 problem behavior variables into five subscales. The subscales were then regressed onto 11 individual and sumscore variables from eight hypotheses about adolescent leisure-time use.
Altogether, four of the eight hypotheses were supported by the data, demonstrating relationships between how and with whom adolescents use their leisure time, and their proneness toward problem behaviors. Specifically, unsupervised leisure-time activities were positively related to problem behaviors, sharing 16% of the variance. Organized leisure-time activities were negatively related to problem behaviors, sharing 9% of the variance. Adolescents who spent more time with family members and less time with peers demonstrated fewer problem behaviors, sharing 19% of the variance. Also, adolescents who confide their personal problems to adults, not peers, showed a lower tendency for problem behaviors, sharing 14% of the variance. The results support relationships between adolescent social environment, particularly leisure-time use, and problem behaviors
QED \otimes QCD Threshold Corrections at the LHC
We use the theory of YFS resummation to compute the size of the expected
resummed soft radiative threshold effects in precision studies of heavy
particle production at the LHC, where accuracies of 1 percent are desired in
some processes. We find that the soft QED threshold effects are at the level of
0.3 percent whereas the soft QCD threshold effects enter at the level of 20
percent and hence both must be controlled to be on the conservative side to
achieve such goals.Comment: 8 pages, no figures; improved text; improved refs. and tex
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