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A proposal to study Lambda0 polarization in the inclusive reaction p + p --> Lambda0 + anything with a liquid hydrogen target

Description: It is proposed that the {Lambda}{sup 0} polarization recently observed in inclusive production of {Lambda}{sup 0} by 300 GeV protons on beryllium be studied with 400 GeV protons in liquid hydrogen. A range of scaling variables 0 {le} p{sub +} {le} 2.3 GeV/c and .1 {le} X {le} 1 will be covered with good statistics. A total run of 150 hours is requested.
Date: September 1, 1975
Creator: Bunce, G.; Pondrom, L.; March, R.; /Wisconsin U., Madison; Devlin, T.; Edwards, R. et al.
Partner: UNT Libraries Government Documents Department

Measurement of the sigma^o Lifetime

Description: The Coulomb production of {Sigma}{sup 0} hyperons on uranium and nickel nuclei has been measured in a beam of {Lambda} hyperons at the CERN Proton Synchrotron. The results for the {Sigma}{sup 0} lifetime, {tau}{Sigma}{sup 0} = (0.58 {+-} 0.13) x 10{sup -19} sec, and for the {Sigma}{sup 0}-{Lambda} magnetic transition moment, |{mu}{Sigma}{sub {Lambda}}| = (1.82{sub -0.18}{sup +0.25}) nuclear magnetons, are in agreement with SU(3) predictions.
Date: March 1, 1972
Creator: Devlin, T.J.; U., /Rutgers; March, R.H.; Pondrom, L.G.; U., /Wisconsin; Overseth, O.E. et al.
Partner: UNT Libraries Government Documents Department

Search for a neutral Higgs boson decaying to a W boson pair in p antip collisions at s**(1/2) = 1.96-TeV

Description: The authors present the results of a search for standard model Higgs boson production with decay to WW*, identified through the leptonic final states e{sup +}e{sup -} {bar {nu}}{nu}, e{sup {+-}}{mu}{sup {-+}} {bar {nu}}{nu} and {mu}{sup +} {mu}{sup -} {bar {nu}}{nu}. This search uses 360 pb{sup -1} of data collected from p{bar p} collisions at {radical}s = 1.96 TeV by the upgraded Collider Detector at Fermilab (CDF II). They observe no signal excess and set 95% confidence level upper limits on the production cross section times branching ratio for the Higgs boson to WW* or any new scalar particle with similar decay products. These upper limits range from 5.5 to 3.2 pb for Higgs boson masses between 120 and 200 GeV/c{sup 2}.
Date: May 1, 2006
Creator: Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G. et al.
Partner: UNT Libraries Government Documents Department

Comparison of Air Fluorescence and Ionization Measurements of E.M. Shower Depth Profiles: Test of a UHECR Detector Technique

Description: Measurements are reported on the fluorescence of air as a function of depth in electromagnetic showers initiated by bunches of 28.5 GeV electrons. The light yield is compared with the expected and observed depth profiles of ionization in the showers. It validates the use of atmospheric fluorescence profiles in measuring ultra high energy cosmic rays.
Date: October 7, 2005
Creator: Belz, J.; Cao, Z.; Huentemeyer, P.; Jui, C.C.H.; Martens, K.; Matthews, J. et al.
Partner: UNT Libraries Government Documents Department

The Effect of Host Galaxies on Type Ia Supernovae in the SDSS-II Supernova Survey

Description: We present an analysis of the host galaxy dependencies of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We re-discover, to high significance, the strong correlation between host galaxy type and the width of the observed SN light curve, i.e., fainter, quickly declining SNe Ia favor passive host galaxies, while brighter, slowly declining Ia's favor star-forming galaxies. We also find evidence (at between 2 to 3{sigma}) that SNe Ia are {approx_equal} 0.1 magnitudes brighter in passive host galaxies, than in star-forming hosts, after the SN Ia light curves have been standardized using the light curve shape and color variations: This difference in brightness is present in both the SALT2 and MCLS2k2 light curve fitting methodologies. We see evidence for differences in the SN Ia color relationship between passive and star-forming host galaxies, e.g., for the MLCS2k2 technique, we see that SNe Ia in passive hosts favor a dust law of R{sub V} {approx_equal} 1, while SNe Ia in star-forming hosts require R{sub V} {approx} 2. The significance of these trends depends on the range of SN colors considered. We demonstrate that these effects can be parameterized using the stellar mass of the host galaxy (with a confidence of > 4{sigma}) and including this extra parameter provides a better statistical fit to our data. Our results suggest that future cosmological analyses of SN Ia samples should include host galaxy information.
Date: May 1, 2010
Creator: Lampeitl, Hubert; /Portsmouth U., ICG; Smith, Mathew; /Cape Town U. /Portsmouth U., ICG; Nichol, Robert C.; /Portsmouth U., ICG et al.
Partner: UNT Libraries Government Documents Department

Techniques of the FLASH Thin Target Experiment

Description: The fluorescence yield in air is reported for wavelength and pressure ranges of interest to ultra-high energy cosmic ray detectors. A 28.5 GeV electron beam was used to excite the fluorescence. Central to the approach was the system calibration, using Rayleigh scattering of a nitrogen laser beam. In atmospheric pressure dry air, at 304 K the yield is 20.8 {+-} 1.6 photons per MeV.
Date: October 30, 2007
Creator: Abbasi, R.; Abu-Zayyad, T.; Belov, K.; Belz, J.; U., /Utah; Bergman, D.R. et al.
Partner: UNT Libraries Government Documents Department

Simplified Models for LHC New Physics Searches

Description: This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the 'Topologies for Early LHC Searches' workshop, held at SLAC in September of 2010, the purpose of which was to develop a set of representative models that can be used to cover all relevant phase space in experimental searches. Particular emphasis is placed on searches relevant for the first {approx} 50-500 pb{sup -1} of data and those motivated by supersymmetric models. This note largely summarizes material posted at http://lhcnewphysics.org/, which includes simplified model definitions, Monte Carlo material, and supporting contacts within the theory community. We also comment on future developments that may be useful as more data is gathered and analyzed by the experiments.
Date: June 1, 2012
Creator: Alves, Daniele; /SLAC; Arkani-Hamed, Nima; /Princeton, Inst. Advanced Study; Arora, Sanjay; /Rutgers U., Piscataway et al.
Partner: UNT Libraries Government Documents Department