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Spin models of the proton

Description: We have constructed a model of the proton spin based on a broken SU(6) parameterization for the spin-weighted valence quark distributions in a longitudinally polarized proton. The polarized sea and gluon distributions are assumed to have simple relations to the corresponding unpolarized structure functions. The sum rules, which involve the non-singlet components of the structure function xg/sub 1/, imply that the valence quarks carry about 78% of the proton spin, while the spin carried by sea quarks is negative. Recent EMC data suggest a model in which the sea quarks carry a large negative polarization, whereas certain theoretical arguments favor a model with a smaller negatively polarized sea. These models are discussed with reference to the sum rules. Experiments are suggested which will discriminate between these models. 24 refs., 4 figs.
Date: October 20, 1988
Creator: Ramsey, G.P.
Partner: UNT Libraries Government Documents Department

A possible early experimental test for a large G(x,QS)

Description: A proposal that the net spin carried by gluons in a polarized proton may be very large compared to 1/2 has recently received considerable theoretical attention. There exists a unique opportunity to test for this dramatic possibility using an existing experimental setup. We urge the consideration of a precision measurement (+-10 b) of sigma/sub L//sup jet/(pp; p0, s) at p0S = 5 GeVS and s = 400 GeVS using the Fermilab polarized beam facility. 10 refs.
Date: October 6, 1988
Creator: Sivers, D. & Ramsey, G.
Partner: UNT Libraries Government Documents Department

A comparison of spin observable predictions for RHIC

Description: There have been many versions of spin-dependent parton distributions in the literature. Although most agree with present data within uncertainties, they are based upon different physical assumptions. Some physical models are discussed and the corresponding predictions for double spin asymmetries are shown. A summary of the most feasible measurements in the appropriate kinematic regions at RHIC, which should yield the most useful information about the polarized gluon distribution, is given.
Date: February 2, 2000
Creator: Ramsey, G. P.
Partner: UNT Libraries Government Documents Department

Physics results from polarized DIS.

Description: We have extracted polarized nucleon distributions from recent data at CERN, SLAC and DESY. The flavor-dependent valence and sea quark spin distributions are determined for each experiment. We take into account possible differences in the up and down sea distributions, and assume that the strange sea contribution is suppressed by mass effects. Physics results determined from different experiments are compared, including higher order corrections.
Date: March 23, 1998
Creator: Ramsey, G. P.
Partner: UNT Libraries Government Documents Department

Polarized parton distributions and the polarized gluon asymmetry.

Description: The flavor-dependent valence, sea quark and antiquark spin distributions can be determined separately from theoretical assumptions and experimental data. The authors have determined the valence distributions using the Bjorken sum rule and have extracted polarized sea distributions, assuming that the quarks and anti-quarks for each flavor are symmetric. Other experiments have been proposed which will allow them to completely break the SU(3) symmetry of the sea flavors. To create a physical model for the polarized gluons, they investigate the gluon spin asymmetry in a proton, A{sub G}(x,Q{sup 2}) = {Delta}G(x,Q{sup 2})/G(x,Q{sup 2}). By assuming that this is approximately Q{sup 2} invariant, they can completely determine the x-dependence of this asymmetry, which satisfies constituent counting rules and reproduces the basic results of the Bremsstrahlung model originated by Close and Sivers. This asymmetry can be combined with the measured unpolarized gluon density, G(x,Q{sup 2}) to provide a prediction for {Delta}G(x,Q{sup 2}). Existing and proposed experiments can test both the prediction of scale-invariance for A{sub G}(x,Q{sup 2}) and the nature of {Delta}G itself. These models can be discussed along with suggestions for specific experiments which can be performed at energies typical of HERA, RHIC and LHC to determine these polarized distributions.
Date: February 6, 2002
Creator: Ramsey, G. P.
Partner: UNT Libraries Government Documents Department

Polarization and N-N elastic scattering amplitudes

Description: We discuss the role of polarization measurements and scattering amplitudes for elastic nucleon-nucleon processes at high energy. The relative normalization of these amplitudes involves a ``leading order form factor`` which we determine empirically. These amplitudes provide an economical description of a large body of existing data and make some nontrivial predictions for spin observables. In particular, we have investigated cross sections and asymmetry data at large angles (including 90{degrees} c.m.) and the fixed {vert_bar} t {vert_bar}, large s region, dominated by the three-gluon exchange mechanism. Our results indicate that polarization experiments can test basic QCD elements such as helicity conservation, wave function properties and the interplay between various interaction mechanisms. The significance of this analysis will be discussed in terms of specific polarization experiments, which can be performed at Fermilab and Brookhaven (RHIC.AGS).
Date: October 7, 1994
Creator: Ramsey, G. P.
Partner: UNT Libraries Government Documents Department

Testing proton spin models with polarized beams

Description: We review models for spin-weighted parton distributions in a proton. Sum rules involving the nonsinglet components of the structure function xg{sub 1}{sup p} help narrow the range of parameters in these models. The contribution of the {gamma}{sub 5} anomaly term depends on the size of the integrated polarized gluon distribution and experimental predictions depend on its size. We have proposed three models for the polarized gluon distributions, whose range is considerable. These model distributions give an overall range is considerable. These model distributions give an overall range of parameters that can be tested with polarized beam experiments. These are discussed with regard to specific predictions for polarized beam experiments at energies typical of UNK.
Date: November 25, 1991
Creator: Ramsey, G. P.
Partner: UNT Libraries Government Documents Department

Elastic spin observables and proton wave function normalization at large t

Description: We summarize the role of spin observables in testing the foundations of exclusive QCD at large t. Polarized elastic scattering experiments can shed light on fundamental properties of protons, such as helicity conservation, normalization of the wave function and structure. Specific QCD motivated predictions for the spin observables are presented, which can be tested at polarized proton beam facilities. In this paper, two kinematic regions are considered: 90{degrees} c.m. at large {vert_bar} t {vert_bar} and the intermediate hard scattering regime: m{sub p}{sup 2} {much_lt}{vert_bar} t {vert_bar}{much_lt} s. Theoretical models, which predict the spin observables in these regions, are reviewed. These are compared with present elastic pp data and a program is suggested for future elastic polarized pp scattering experiments, which can be used to further our knowledge of proton structure.
Date: November 29, 1993
Creator: Ramsey, G. P.
Partner: UNT Libraries Government Documents Department

Parton distributions from SMC and SLAC data

Description: We have extracted spin-weighted parton distributions in a proton from recent data at CERN and SLAC. The valence, sea quark and Antiquark spin-weighted distributions are determined separately. The data are all consistent with a small to moderate polarized gluon distribution, so that the anomaly term is not significant in the determination of the constituent contributions to the spin of the proton. We have analyzed the consistency of the results obtained from various sets of data and the Biorken sum rule. Although all data are consistent with the sum rule, the polarized distributions from different experiments vary, even with higher order QCD corrections taken into account. Results split into two models, one set implying a large polarized strange sea which violates the positivity bound, and the other set yielding a smaller polarized strange sea. Only further experiments which extract information about the polarized sea will reconcile these differences. We suggest specific experiments which can be performed to determine the size of the polarized sea and gluons.
Date: January 4, 1996
Creator: Ramsey, G. P. & Goshtasbpour, M.
Partner: UNT Libraries Government Documents Department

Using spin to probe hadronic structure

Description: The theoretical and experimental status of high energy spin phenomena is summarized, with emphasis on the spin properties of nucleons. It is stressed that crucial tests of the Standard Model can be made with polarization experiments. By performing the experiments discussed here, the authors will reveal important constituent and composite properties of protons and neutrons. The future prospects for planned polarization experiments are discussed.
Date: December 2, 1994
Creator: Ramsey, G.P.
Partner: UNT Libraries Government Documents Department

Global positioning automatic vehicle location system

Description: Los Alamos National Laboratory (LANL) is a unique facility covering over 43 square miles. The Emergency Management and Response Office (EM&R) is required to respond, provide Incident Command (IC), and coordination for all Laboratory emergencies. This requires IC`s and support staff to respond to the actual scene of the incident. Since the IC is under numerous constraints and stress, the office wanted the capability of locating the EM&R vehicles on an electronic map. An automated vehicle location (AVL) system was required for the additional safety of the emergency response personal. The requirements for the AVL system include total automatic tracking and low cost. After careful consideration, it was determined that the most efficient and cost effective system would be based on packet radio technology as the transmission media. The location is determined by the Department of Defense Global Positioning System (GPS). The system that was designed and constructed required four components to be interfaced and communicate with each other. The first component was a GPS receiver which actually provides the location information, equipped with a digital interface to communicate location information remotely. The second component is a modem that interfaces the GPS digital interface information to a radio. The third component is the radio itself which allows for the actual information transfer from the remote GPS receiver and modem. The fourth component is the software package that provides moving maps and displays the vehicle location on that map. The equipment was all commercial off-the-shelf that only required proper integration and packaging for the AVL application. This paper describes the steps taken in the integration of the equipment into the AVL package.
Date: March 1, 1997
Creator: Papatheofanis, B.J.; Hasenack, M.L.; Teller, R.T. & Ramsey, G.F.
Partner: UNT Libraries Government Documents Department

Spin structure of the proton and large p{sub T} processes in polarized pp collisions

Description: QCD motivated polarized parton distributions, evolved directly in x-space, are used to predict rates for prompt photon and jet production at RHIC and HERA-N center of mass energies. Various scenarios for the polarized gluon distributions are considered and compared, and the possibility of using large p{sub T} processes in polarized pp collision experiments to choose between them is analyzed.
Date: October 27, 1998
Creator: Gordon, L. E. & Ramsey, G. P.
Partner: UNT Libraries Government Documents Department

Los Alamos National Laboratory emergency management plan. Revision 1

Description: The Laboratory has developed this Emergency Management Plan (EMP) to assist in emergency planning, preparedness, and response to anticipated and actual emergencies. The Plan establishes guidance for ensuring safe Laboratory operation, protection of the environment, and safeguarding Department of Energy (DOE) property. Detailed information and specific instructions required by emergency response personnel to implement the EMP are contained in the Emergency Management Plan Implementing Procedure (EMPIP) document, which consists of individual EMPIPs. The EMP and EMPIPs may be used to assist in resolving emergencies including but not limited to fires, high-energy accidents, hazardous material releases (radioactive and nonradioactive), security incidents, transportation accidents, electrical accidents, and natural disasters.
Date: July 15, 1998
Creator: Ramsey, G.F.
Partner: UNT Libraries Government Documents Department

Quality assurance plan for the data acquisition and management system for monitoring the fuel oil spill at the Sandia National Laboratories installation in Livermore, California

Description: In February 1975, the accidental puncture of an underground transfer line buried about 4 ft below the ground surface at the SNL installation in Livermore, California, resulted in the release of approximately 225.5 m{sup 3} of No. 2 diesel fuel. This report describes the formal quality assurance plan that will be used for the data acquisition and management system developed to monitor a bioremediation pilot study by Argonne National Laboratory in association with Sandia National Laboratories. The data acquisition and management system will record the site data during the bioremediation effort and assist users in site analysis. The designs of the three major subsystems of this system are described in this report. Quality assurance criteria are defined for the management, performance, and assessment of the system. Finally, the roles and responsibilities for configuration management of this system are defined for the entire life cycle of the project.
Date: April 1, 1995
Creator: Peerenboom, J.P.; Leser, C.C.; Ramsey, G.M. & Widing, M.A.
Partner: UNT Libraries Government Documents Department

Emergency Medical Rescue in a Radiation Environment

Description: Previous experience with emergency medical rescues in the presence of radiation or contamination indicates that the training provided to emergency responders is not always appropriate. A new course developed at Los Alamos includes specific procedures for emergency response in a variety of radiological conditions.
Date: September 14, 1999
Creator: Briesmeister, L.; Ellington, Y.; Hollis, R.; Kunzman, J.; McNaughton, M.; Ramsey, G. et al.
Partner: UNT Libraries Government Documents Department

Spin observables for nucleon-nucleon elastic scattering at large momentum transfer

Description: We discuss amplitudes for elastic nucleon-nucleon scattering at high energy. The helicity-conserving amplitudes are modeled using a combination of the quark-interchange and the Landshoff mechanisms of perturbative QCD. The relative normalization of these two sets of amplitudes involves a leading order form factor'' which we determine empirically. Our theoretically motivated amplitudes provide an economical description of a large body of existing data and make nontrivial predictions for spin observables. 8 refs., 4 figs.
Date: August 14, 1990
Creator: Ramsey, G.P. (Loyola Univ., Chicago, IL (USA). Dept. of Physics Argonne National Lab., IL (USA))
Partner: UNT Libraries Government Documents Department

Testing proton spin models with polarized beams

Description: We review models for spin-weighted parton distributions in a proton. Sum rules involving the nonsinglet components of the structure function xg{sub 1}{sup p} help narrow the range of parameters in these models. The contribution of the {gamma}{sub 5} anomaly term depends on the size of the integrated polarized gluon distribution and experimental predictions depend on its size. We have proposed three models for the polarized gluon distributions, whose range is considerable. These model distributions give an overall range is considerable. These model distributions give an overall range of parameters that can be tested with polarized beam experiments. These are discussed with regard to specific predictions for polarized beam experiments at energies typical of UNK.
Date: November 25, 1991
Creator: Ramsey, G.P. (Loyola Univ., Chicago, IL (United States). Dept. of Physics Argonne National Lab., IL (United States))
Partner: UNT Libraries Government Documents Department

Experimental tests of proton spin models

Description: We have developed models for the spin-weighted quark and gluon distribution in a longitudinally polarized proton. The model parameters are determined from current algebra sum rules and polarized deep-inelastic scattering data. A number of different scenarios are presented for the fraction of spin carried the constituent parton distributions. A possible long-range experimental program is suggested for measuring various hard scattering processes using polarized lepton and proton beams. With the knowledge gained from these experiments, we can begin to understand the parton contributions to the proton spin. 28 refs., 5 figs.
Date: November 3, 1989
Creator: Ramsey, G.P. (Loyola Univ., New Orleans, LA (USA). Dept. of Physics Argonne National Lab., IL (USA). High Energy Physics Div.)
Partner: UNT Libraries Government Documents Department