Search for W-prime boson production in the top quark decay channel (open access)

Search for W-prime boson production in the top quark decay channel

We present a search for the production of a new heavy gauge boson W' that decays to a top quark and a bottom quark. We have analyzed 230 pb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider at a center-of-mass energy of 1.96 TeV. No significant excess of events is found in any region of the final state invariant mass distribution. We set upper limits on the production cross section of W bosons at the 95% confidence level for several different W' boson masses. We exclude masses below 610 GeV for a W' boson with standard-model-like couplings, below 630 GeV for a W' boson with right-handed couplings that is allowed to decay to both leptons and quarks, and below 670 GeV for a W' boson with right-handed couplings that is only allowed to decay to quarks.
Date: July 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Use of Federated Object Modeling to Develop a Macro-System Model for the U.S. Department of Energy's Hydrogen Program; Preprint (open access)

Use of Federated Object Modeling to Develop a Macro-System Model for the U.S. Department of Energy's Hydrogen Program; Preprint

DOE is working on changing transportation fuel to hydrogen. To assist in that effort, we are developing a macro-system model that will link existing or developmental component models together.
Date: July 1, 2006
Creator: Ruth, M. F.; Vanderveen, K. B. & Sa, T. J.
Object Type: Article
System: The UNT Digital Library
Search for the Standard Model Higgs Boson in the p anti-p ---> ZH ---> nu anti-nu b anti-b channel (open access)

Search for the Standard Model Higgs Boson in the p anti-p ---> ZH ---> nu anti-nu b anti-b channel

We report a search for the standard model (SM) Higgs boson based on data collected by the D0 experiment at the Fermilab Tevatron Collider, corresponding to an integrated luminosity of 260 pb{sup -1}. We study events with missing transverse energy and two acoplanar b-jets, which provide sensitivity to the ZH production cross section in the {nu}{bar {nu}}B{bar b} channel and to WH production, when the lepton from the W {yields} {ell}{nu} decay is undetected. The data are consistent with the SM background expectation, and we set 95% C.L. upper limits on {sigma}(p{bar p} {yields} ZN/WH) x B(H {yields} b{bar b}) from 3.4/8.3 to 2.5/6.3 pb, for Higgs masses between 105 and 135 GeV.
Date: July 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for associated Higgs boson production WH ---> WWW* ---> l+- nu l-prime+- nu-prime + X in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for associated Higgs boson production WH ---> WWW* ---> l+- nu l-prime+- nu-prime + X in p anti-p collisions at s**(1/2) = 1.96-TeV

The authors present a search for associated Higgs boson production in the process p{bar p} {yields} WH {yields} WWW* {yields} {ell}{sup {+-}}{nu} {ell}{prime}{sup {+-}} {nu}{prime} + X in final states containing two like-sign isolated electrons or muons (e{sup {+-}}e{sup {+-}}, e{sup {+-}} {mu}{sup {+-}}, or {mu}{sup {+-}} {mu}{sup {+-}}). The search is based on D0 Run II data samples corresponding to integrated luminosities of 360-380 pb{sup -1}. No excess is observed over the predicted standard model background. They set 95% C.L. upper limits on {sigma}(p{bar p} {yields} WH) x Br(H {yields} WW*) between 3.2 and 2.8 pb for Higgs masses from 115 to 175 GeV.
Date: July 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
Search for scalar leptoquarks in the acoplanar jet topology in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for scalar leptoquarks in the acoplanar jet topology in p anti-p collisions at s**(1/2) = 1.96-TeV

A search for leptoquarks has been performed in 310 pb{sup -1} of data from p{bar p} collisions at a center-of-mass energy of 1.96 TeV, collected by the D0 detector at the Fermilab Tevatron Collider. The topology analyzed consists of acoplanar jets with missing transverse energy. The data show good agreement with standard model expectations, and a lower mass limit of 136 GeV has been set at the 95% C.L. for a scalar leptoquark decaying exclusively into a quark and a neutrino.
Date: July 1, 2006
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type: Article
System: The UNT Digital Library
History and Evolution of Control Banding: A Review (open access)

History and Evolution of Control Banding: A Review

Control Banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents often encountered in the workplace. The original CB model was developed within the pharmaceutical industry; however, the modern movement involves models developed for non-experts to input hazard and exposure potential information for bulk chemical processes, receiving control advice as a result. The CB approach utilizes these models for the dissemination of qualitative and semi-quantitative risk assessment tools being developed to complement the traditional industrial hygiene model of air sampling and analysis. It is being applied and tested in small and medium size enterprises (SMEs) within developed countries and industrially developing countries; however, large enterprises (LEs) have also incorporated these strategies within chemical safety programs. Existing research of the components of the most available CB model, the Control of Substances Hazardous to Health (COSHH) Essentials, has shown that exposure bands do not always provide adequate margins of safety, that there is a high rate of under-control errors, that it works better with dusts than with vapors, that there is an inherent inaccuracy in estimating variability, and that when taken together the outcomes of this model may lead to potentially inappropriate workplace confidence in chemical exposure reduction in some …
Date: July 19, 2006
Creator: Zalk, D. & Nelson, D.
Object Type: Article
System: The UNT Digital Library
Phase transformation of "chem-prep" PZT 95/5-2Nb HF1035 ceramic under quasi-static loading conditions. (open access)

Phase transformation of "chem-prep" PZT 95/5-2Nb HF1035 ceramic under quasi-static loading conditions.

Specimens of poled and unpoled ''chem-prep'' PNZT ceramic from batch HF1035 were tested under hydrostatic, uniaxial, and constant stress difference loading conditions at -55, 25, and 75 C. The objective of this experimental study was to characterize the mechanical properties and conditions for the ferroelectric (FE) to antiferroelectric (AFE) phase transformations of this ''chem-prep'' PNZT ceramic to aid grain-scale modeling efforts in developing and testing realistic response models for use in simulation codes. As seen from a previously characterized material (batch HF803), poled ceramic from HF1035 was seen to undergo anisotropic deformation during the transition from a FE to an AFE phase. Also, the phase transformation was found to be permanent for the two low temperature conditions, whereas the transformation can be completely reversed at the highest temperature. The rates of increase in the phase transformation pressures with temperature were practically identical for both unpoled and poled PNZT HF1035 specimens. We observed that temperature spread the phase transformation over mean stress analogous to the observed spread over mean stress due to shear stress. Additionally, for poled ceramic samples, the FE to AFE phase transformation was seen to occur when the normal compressive stress, acting perpendicular to a crystallographic plane about …
Date: July 1, 2006
Creator: Montgomery, Stephen Tedford; Lee, Moo Yul; Meier, Diane A. & Hofer, John H.
Object Type: Report
System: The UNT Digital Library
Forward osmosis :a new approach to water purification and desalination. (open access)

Forward osmosis :a new approach to water purification and desalination.

Fresh, potable water is an essential human need and thus looming water shortages threaten the world's peace and prosperity. Waste water, brackish water, and seawater have great potential to fill the coming requirements. Unfortunately, the ability to exploit these resources is currently limited in many parts of the world by both the cost of the energy and the investment in equipment required for purification/desalination. Forward (or direct) osmosis is an emerging process for dewatering aqueous streams that might one day help resolve this problem. In FO, water from one solution selectively passes through a membrane to a second solution based solely on the difference in the chemical potential (concentration) of the two solutions. The process is spontaneous, and can be accomplished with very little energy expenditure. Thus, FO can be used, in effect, to exchange one solute for a different solute, specifically chosen for its chemical or physical properties. For desalination applications, the salts in the feed stream could be exchanged for an osmotic agent specifically chosen for its ease of removal, e.g. by precipitation. This report summarizes work performed at Sandia National Laboratories in the area of FO and reviews the status of the technology for desalination applications. At …
Date: July 1, 2006
Creator: Miller, James Edward & Evans, Lindsey R.
Object Type: Report
System: The UNT Digital Library
Plant Wide Assessment for Johns Manville Waterville Ohio Plant 1 (open access)

Plant Wide Assessment for Johns Manville Waterville Ohio Plant 1

The report describes activites carried out at the palnt to identify energy savings in various energy user systems. The results list areas of energy savings potential and metods of energy savings.
Date: July 2, 2006
Creator: Kissock, Kelly & Thekdi, Arvind
Object Type: Report
System: The UNT Digital Library