A New Device for Relative Luminosity Measurements at PHENIX. HARSHIL PARIKH (University of Illinois at Urbana-Champaign, Urbana-Champaign, IL 61801) WEI XIE (Brookhaven National Laboratory, Upton, NY 11973)

The PHENIX collaboration probes spin dependent nucleon structure in polarized proton collisions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. These measurements include the study of the gluon spin contribution to the proton spin through the longitudinal double spin asymmetries which requires a precise measurement of relative luminosities. During the proton-proton run in 2002 and 2003, a beam-beam counter (BBC) was used as the relative-luminosity monitor. In future high luminosity runs, the probability of multiple proton-proton collisions per bunch crossing will be too significant to allow for accurate measurement of relative-luminosity using the BBC. We propose a new relative luminosity telescope (RLT) which consists of three layers of pad chambers and is installed in the vicinity of the beam-pipe in the PHENIX interaction region. The new instrument is expected to provide measurements with high resolution in high luminosity environment at RHIC. Monte Carlo simulations are being performed to optimize the detector configuration. The acceptance of the proposed RLT will be small enough to avoid the problem of multiple collisions per bunch crossing. The RLT is also expected to be able to determine the collision vertex through the correlation of channels in the three pad-chamber stations and thus will help to measure precisely acceptance variations as function of the collision vertex. This has been one of the major uncertainties in measuring the relative luminosity in the previous runs.

Developing of software for calculating the ionization cross-sections and simulating evolution of ionic charge states in an ion trap. PARMINDER SINGH (Monroe Community College, Rochester, NY 14623) ALEXANDER PIKIN (Brookhaven National Laboratory, Upton, NY 11973)

My activity was related to modifying the existing and writing new software for simulating charge states distribution of ions confined within the electron beam. The existing program SUK was limited to 10 elements and was not able to simulate a variety of elements, which BNL ion source group was planning to produce. Currently the data on ionization cross-sections are very scarce and scattered in different sources. These data are frequently needed for atomic physics analysis, especially for analysis of ionization. Therefore, developing of the program, which can calculate the ionization cross-section for different ion species and charge states were very useful for the atomic physics analysis of the group. The task: 1. Extension of the range of program SUK, which calculates dynamics of ionic charge states in the electron beam to 10 new elements. 2. Writing a separate program for calculating the ionization cross-sections of ions by electron impact for the specific electron energy. 3. Modifying this program for calculating the ionization cross-sections in a defined energy range of electrons for specified number of points.

Generating Randon Numbers to Simulate Experimental Data. BLENDELL REGISTER-WHEATLE (Stony Brook University, Stony Brook, NY 11973) CAROL SCARLETT (Brookhaven National Laboratory, Upton, NY 11973)

I am currently working on simulating data. To do this, sets of FORTRAN program utilizing random numbers generation have been developed. These programs are currently being used to answer questions about the geometric acceptance of a random distribution of vector, given a specific detector geometry.

Investigation of Molecular Electrical Properties Using Au/Ge Thin Films. TANINA BRADLEY (North Carolina A&T State University, Greensboro, NC 27411) CHRISTOPHER JESSAMY (North Carolina A&T State University, Greensboro, NC 27411) MYRON STRONGIN (Brookhaven National Laboratory, Upton, NY 11973)

In this work we present the results of the nano-structural studies and electrical characterization of Gold (Au) films on ambient temperature or cooled amorphous Germanium (Ge) substrates. We were able to produce monolayers of Au that are 0.3-3 nm thick. These films were fabricated under high vacuum conditions (~10^-8 Torr) using thermal evaporation. We used a simple series resistor circuit for in situ measurement of resistance of the film during deposition. This method allowed us to detect the continuous formation of the Au layers. The sheet resistance was measured as a function of temperature and thickness. The nano-structure of the films was determined using Atomic Force Microscopy (AFM). For the thinnest layers of Au on Ge we saw no structure in the AFM and we suspect that the thin Au layers alloy with the Ge. The temperature dependence of sheet resistance shows activated behavior. These initial experiments indicate that it may be possible to study thin layers of Au with sheet resistance approaching 10^12 O/. This possibility could result in experiments measuring the change in resistance when thiols and other molecules are put on the Au surface.

Mapping the Magnetic Field in the PHENIX Detector at the Relativistic Heavy Ion Collider. ANDREW MCCORMICK (University of Illinois at Urbana-Champaign, Urbana-Champaign, IL 61801) ACHIM FRANZ (Brookhaven National Laboratory, Upton, NY 11973)

The PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory studies the properties of the strong nuclear force and the nature of hadronic matter under extreme conditions. The PHENIX detector consists of four independent magnetic spectrometers which are used to identify the reaction products of ion-ion and polarized proton-proton collisions and to measure their momenta. The goal of this research project was to accurately map the magnetic fields generated by the magnet systems in the central PHENIX spectrometer arms. When a charged particle passes through a magnetic field its trajectory is bent an amount proportional to the strength of the magnetic field. The amount the particle bends is also dependent on the exact charge and mass of the particle. Thus, if a detailed map of the magnetic field is available, it is possible to compare the actual path of a particle with the theoretically predicted path of a certain type of particle. These comparisons can then be used to help identify the particle in question.

Photomultiplier Calibration for Measuring Proton Extinction Rate for KOPIO Experiment. BLENDELL REGISTER-WHEATLE (Broward Community College, Davie, FL 33314) CAROL SCARLETT (Brookhaven National Laboratory, Upton, NY 11973)

ABSTRACT: As part of the KOPIO Beam Monitor, small Photo Multiplier Tubes(PMTs) were calibrated so that they could be used in proton extraction rate measurements. In analyzing the response of the PMT's, two different studies were done. The first was the single photoelectron response of the PMTs; then a high voltage scan study was conducted. Two additional sources were also measured and recorded for comparison. The findings based on the study of single photoelectrons showed that both PMTs produced a gain of about 5 x 106 with a high voltage setting at 1400. Also the findings showed that the Ruthenium source produced 7 photoelectrons and 0 for the cosmic rays.

Second Order Effects in BPM Response. ADAM GRAY (University of Georgia, Athens, GA 30609) THOMAS RUSSO (Brookhaven National Laboratory, Upton, NY 11973)

Six of The Department of Energy’s laboratories are teaming together to build the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. The SNS project will focus on research using intense pulsed neutron beams. Brookhaven National Laboratory’s Collider-Accelerator Department is responsible for the designing, building, and testing of the Ring System for the SNS project. Beam Position Monitors (BPMs) are used to determine beam position in particle accelerators. Magnets with adjustable magnetic fields, called dipoles and quadrupoles, are built and strategically placed in accelerators to manipulate the beam’s position so that it is in the center of the beam pipe. These magnets bend and focus the beam. The electrical center of the BPM, the point where current from the beam is the same on all BPM electrodes, should be extraordinarily close to the mechanical center, the center of the aperture. Using a scanning apparatus, the coordinates of these centers are determined. A raster scan, a scan that spans the entire aperture in 1.0 mm increments, is performed. The aperture that the scan spans is dependent on the diameter of the BPM. A larger BPM has a larger aperture. The results from the scan are recorded in a spreadsheet. This scan reveals how well the BPM was designed and built. As the wire of the scanning apparatus gets closer to a particular electrode, the signal in that electrode should increase proportionally to the decrease in signal of the opposite electrode. The goal is to calculate a regression function that improves the accuracy of the data.

Spin Dependence in Proton-Proton Elastic Scattering at RHIC. DAVID MORSE (University of Rochester, Rochester, NY 14627) DR. WLODEK GURYN (Brookhaven National Laboratory, Upton, NY 11973)

The pp2pp experiment, which finished taking data in May of 2003 at Brookhaven National Lab at the Relativistic Heavy Ion Collider, is investigating the spin dependence of elastic proton-proton collisions at the center of mass energy range 50 < vs < 500 GeV. Because an elastic collision is one where the sum of the momenta of the outgoing protons is zero, the scattering angles F of the two protons are equal and have opposite signs, with the partial components Fx , Fy and Fz following the same relationship. The experiment is in the final stages of analysis. To this end, software must be developed to understand the data. My task is to develop and implement various C++ programs in ROOT, an object oriented data analysis framework. These programs have two main applications. The first is the development of software to determine the spin asymmetry An. Spin asymmetry arises from an electromagnetic interaction between the protons and an interference term from a hadronic interaction, which has never before been measured experimentally at these energies. The errors on these results must also be calculated very carefully, taking into account all possible systematic errors in the experiment. This leads to the other main application, which is to determine which events are truly elastic, thus minimizing the error due to background noise. A useful way to achieve this is to produce a visual aid for reconstructing events. For this I developed an Event Display program, which recognizes and displays the data points on the Si strip detectors. This not only lets us discriminate between elastic and background events, but also helps in understanding the background events themselves. More error analysis will be done by changing parameters in the analysis and examining how the results change. We will not be ready to obtain the final results until all the possible errors have been accounted for.

Statistical Analysis of the KOPIO Test Beam Data. CRYSTAL CANTLEY (St. Joseph's College, Patchogue, NY 11772) MICHAEL SIVERTZ (Brookhaven National Laboratory, Upton, NY 11973)

According to the Big Bang Theory, it is assumed that the creation of matter and antimatter would have been an equal distribution. However, if the laws governing matter and antimatter were symmetrical, then we would not have a universe today. The answer to this intriguing paradox may lie in what is known as charge parity (CP) symmetry violation. The purpose of the KOPIO ( ) experiment is to study rare decays of the neutral K-meson, which seems to display this CP symmetry violation. In order to observe these rare decays taking place, KOPIO makes use of the Alternating Gradient Synchrotron (AGS) accelerator, located at Brookhaven National Laboratory. The most recent test runs using the AGS took place in May of 2004. Through analyzing this data, the performance of the AGS will be improved enabling the KOPIO experiment to study these rare decays, providing useful insight into CP symmetry violation, which may contribute to the dominance of matter over antimatter in the universe. With over two million events represented in the data from the test beam, powerful analytical tools such as the Physics Analysis Workstation (PAW), developed by the CERN laboratory in Geneva, Switzerland, will be used to manipulate the data effectively. This program will take into account the amount of uncertainty in these measurements. Using FORTRAN, a program was created to manage the large amounts of data, in order to make the calculations accessible to PAW. As more is discovered about how the data structures function, it will be necessary to make adjustments in the program to create the most useful histograms of the results. Understanding the findings of the KOPIO experiment may have the capability of testing our knowledge of some of the most basic laws of physics concerning the evolution of the early universe.

Statistical Analysis of the KOPIO Test Beam Data. JENNIFER MABANTA (St. Joseph's College, Patchogue, NY 11772) MICHAEL SIVERTZ (Brookhaven National Laboratory, Upton, NY 11973)

According to the Big Bang Theory, it is assumed that the creation of matter and antimatter would have been an equal distribution. However, if the laws governing matter and antimatter were symmetrical, then we would not have a universe today. The answer to this intriguing paradox may lie in what is known as charge parity (CP) symmetry violation. The purpose of the KOPIO ( ) experiment is to study rare decays of the neutral K-meson, which seems to display this CP symmetry violation. In order to observe these rare decays taking place, KOPIO makes use of the Alternating Gradient Synchrotron (AGS) accelerator, located at Brookhaven National Laboratory. The most recent test runs using the AGS took place in May of 2004. Through analyzing this data, the performance of the AGS will be improved enabling the KOPIO experiment to study these rare decays, providing useful insight into CP symmetry violation, which may contribute to the dominance of matter over antimatter in the universe. With over two million events represented in the data from the test beam, powerful analytical tools such as the Physics Analysis Workstation (PAW), developed by the CERN laboratory in Geneva, Switzerland, will be used to manipulate the data effectively. This program will take into account the amount of uncertainty in these measurements. Using FORTRAN, a program was created to manage the large amounts of data, in order to make the calculations accessible to PAW. As more is discovered about how the data structures function, it will be necessary to make adjustments in the program to create the most useful histograms of the results. Understanding the findings of the KOPIO experiment may have the capability of testing our knowledge of some of the most basic laws of physics concerning the evolution of the early universe.

Study of a Direction Sensitive Photo-Sensor. ZACH PARSONS (University of South Dakota, Vermillion, SD 57069) MILIND DIWAN (Brookhaven National Laboratory, Upton, NY 11973)

A charged particle traveling through a medium will polarize the medium creating radiation. If the speed of the particle is greater than the speed of light in that medium, the radiation is emitted as a coherent wave front known as Cherenkov radiation. The photons all have the same angle with respect to the direction of the particle. This radiation is similar to the sonic boom heard from supersonic aircraft. This Cherenkov radiation can be detected by photo sensors to understand properties of the charged particles. Today’s large water Cherenkov detectors, like Super Kamiokande in Japan, use photomultiplier tubes (PMT’s) to detect the photons. In this report, we studied a new kind of photo detector, a direction sensitive PMT, which uses a lens to transfer the incident photon angle to a position on a detecting surface. We have studied a basic wide angle lens design. The lens was altered to make it cost effective, while at the same time efficient. The resolution of the lens was relaxed in exchange for the tightening of several other parameters. The parameters that were studied included lens thickness, image plane area, system aperture, and distance from lens to image plane.

Testing and Debugging of Sector Crossing Trigger Modifications on the MT2A Trigger Board at E949. DANIEL MINER (Brandeis University, Waltham, MA 2454) GEORGE REDLINGER (Brookhaven National Laboratory, Upton, NY 11973)

E949 is a rare kaon decay experiment designed to measure the magnitude of the matrix element $V_{td}$ in the CKM quark mixing matrix in weak interactions. Recently, an upgrade to a component of the lowest level trigger used in the experiment, known as MT2A (for Meantimer levels T and 2, revision A) was made to increase the acceptance rate of the experiment by introducing the acceptance of sector-crossing events in the T and 2 layer detector arrays. The work done during the course of the project included the testing of the logic and the timing of the three new logic modes introduced by the upgrade as well as the original mode. It also included making any necessary repairs to the board when problems were discovered in the testing process. In the course of the testing, it was determined, after a few repairs, that all the logic modes were fully functional, and the system timing was, depending on the logic mode, either within operational parameters, or able to be made to be so through the use of a minimal amount of time trimming cables.

Using Synchrotron Light Techniques to Study a Native American Artifact: The Wolf’s Head Pouch. ANGELA PADILLA (Hunter College, New York, NY 10021) VIVIAN STOJANOFF (Brookhaven National Laboratory, Upton, NY 11973)

Hair samples of a Native American Indian wolf’s head pouch were analyzed using x-ray fluorescence, small angle x-ray scattering, infrared microspectroscopy, and powder diffraction at the National Synchrotron Light Source at Brookhaven National Laboratory, Upton NY. The wolf’s head pouch is one of eight Native American Indian artifacts now preserved in the armorial collections of the Skokloster Museum in Sweden. There is interest in the study of such perishable artifacts. Perishable artifacts contain cognitive components that identify a culture greater than do artifacts made of stone or bone. The Skokloster artifacts are important because they are made mostly of perishable materials. Perishable materials do not survive in the acidic soils of Southeastern Pennsylvania, in which they are believed to derive, according to Marshall J. Becker of the Department of Anthropology, West Chester University, West Chester, Pennsylvania, the owner of the samples. High lead and zinc content was detected by x-ray fluorescence. Small angle x-ray scattering, infrared microspectroscopy, and powder diffraction all showed evidence that the hairs are mammal and will be discussed. However it remains unclear from which mammal they derived. The wolf’s head pouch was an intricate fabrication of a wolf’s head with only the jaws confirmed to be that of a wolf. All other components were dyed and sewn on. Speculation regarding the mammal hair origin will continue to be researched.

Using Weak Gravitational Lensing to Compare Filters and Study Tomography of a Massive Galaxy Cluster. JOHN KEHAYIAS (Columbia University, New York, NY 10027) MORGAN MAY (Brookhaven National Laboratory, Upton, NY 11973)

We have been working with data from the Deep Lens Survey used in Wittman et al’ s paper “Weak Lensing Discovery and Tomography of a Cluster at z = 0.68” (2003) to study the same galaxy cluster with different weighting/filter functions. When there is a large mass between an observer and distant background galaxies, General Relativity predicts a bending of the light – weak gravitational lensing. By studying this small effect over an entire field, it is statistically feasible to “see” an otherwise dark mass (sensitive to baryonic and dark matter) through a tangential shear (proportional to mass) map. Weighting and filtering are used to optimize the shear maps, and we have studied four different filter functions: NFW (Navarro, Frenk & White 1997), modified Gaussian, aperture mass, and TMF (Tomographic Matched Filtering, Hennawi & Spergel 2004). We have looked at maps produced from the different filters, and calculated signal to noise (by randomizing galaxy ellipticities) to optimize each filter and find the best one. We find that all the filters can be optimized by varying their cutoff parameter and perform nearly equally well. However, TMF performs slightly better, even with the non-optimal NFW as its base filter. In addition, we have used TMF to find redshift information of the cluster. Our results have agreed with what Wittman has found for a redshift estimate and mass maps. Additionally, we used TMF on simulation data from Martin White, where we identified several massive clusters and successfully found their redshifts with tomography.

Vacuum Chamber Pressure Optimization for the Muon-to-Electron Conversion Experiment (MECO). ANDREW MCUMBER (Binghamton University, Binghamton, NY 13902) WILLIAM MORSE (Brookhaven National Laboratory, Upton, NY 11973)

The term MECO describes the multidisciplinary experiment of finding a rare, symmetry-violating process (RSVP). The strict conversion of a muon particle into an electron is of great interest to high-energy physicists, as it is a prediction of Supersymmetry Theory. To meet the challenge of sensing this minute interaction, key components of the reaction chamber must be optimized, with regard to efficiency and cost. While desiring an optimum record of such processes, excessive levels of interference from ambient particles serve to inhibit the obtainment of crucial data. Thus, in observing this elusive effect within the detecting apparatus, a partial vacuum chamber is used. It is in this arena where human factors come into play, as costs are considered. To achieve a maximally evacuated chamber, while acknowledging financial constraints, an analysis of the trajectories at hand becomes necessary. The Maple 9.5 mathematical utility is well suited for the MECO case. Access to its vast collection of functions allows for the plotting of muon paths (pre-reaction). Two material mediums in the reaction center, standard atmosphere and carbon hexafluorane (CF6), both at a variety of pressures (P < 1 atm), are studied for their energy-reducing effects upon the leptons. Initially, adiabatic systems are considered, at first with a constant B-field along the z-axis, and then with a field that decreases in strength with approximate linearity. Finally, gas characteristics are added to the algorithm. Ultimately, the investigation gives forth the most cost-effective vacuum pressure for the experiment.

VBNLTrak: An Interactive Graphical Post Processor for the TriComp™ Particle Accelerator Modeling Suite VbnlTrak: An Interactive Graphical Post Processor for the TriComp™ Particle Accelerator Modeling Suite. ANDREW SIEMION (Sierra College, Rocklin, CA 95677) AHOVI KPONOU (Brookhaven National Laboratory, Upton, NY 11973)

We present the development of the application VbnlTrak, an interactive graphical post-processor for some components of Field Precision’s TriComp 2D™ suite of finite element (FE) electrostatic and magnetostatic field solution and charged particle orbit tracking programs. Although the TriComp suite produces accurate data, the visualization components, which perform functions such as graphing of electric equipotential lines, plotting of particle trajectories and graphical labeling of solution space components, lack certain features that the Brookhaven Preinjector Group’s electron beam ion source (EBIS) team would like to have access to. VbnlTrak serves as an alternative post-processing tool to VTrak, one of the visualization routines distributed with the TriComp suite. The plotting process has been streamlined to allow the complete configuration of plot characteristics before plotting is explicitly executed. Several new plot types have been added which allow the display of axial electric potential, axial magnetic field magnitude, and beam emittance. In addition, a full range of customization options have been added which allow the user much improved control over plot style, annotation and inclusions. New output options, including additional file export selections and the integration of a common windows print dialog have also been added. The user now has the ability to overlay any and all plot types onto a single graph, and all plot components have been made interactively resizable via the implementation of a graphical windowing/layering system. VbnlTrak was written for the Windows environment using a combination of Compaq Visual Fortran and the Winteracter Graphics Libraries. Here we describe the upgrades and additions instituted in VbnlTrak. Selected mathematical and geometric methods used to interpret TriComp solution files and visualize conformal mesh FE data are detailed. Illustrations of the program interface and labeled sample plots are included.

Quantum Efficiency of Metal Photocathodes. MAKINI BYRON (Columbia University, New York, NY 10027) TRIVENI RAO (Brookhaven National Laboratory, Upton, NY 11973)

Photoemission is a naturally occurring phenomenon in which photons striking a metal surface excite electrons and cause them to escape. The quantum efficiency (QE) of this process is defined as the ratio of electrons emitted from a surface to the number of photons that are incident on that surface. The purpose of this experiment was to measure the QE of photocathodes with different surface preparations using a continuous stream of ultraviolet light, and determine the best conditions for an optimum QE. The factors varied were the material of the cathode, the applied electric field, the wavelength of light incident on the cathode, and the "cleanliness" of the metal surface. The cathodes studied were polished copper, lead sputtered copper, and lead sputtered niobium. By using interference filters, the UV light was separated into narrow bandwidths of approximately 20nm, for wavelengths from 200nm to 300nm. A photodiode and meter were used to measure the power of the light incident on the photocathode. The emission of electrons was measured as a current using an electrometer. It was found that the quantum efficiency was greatest with light at shorter wavelengths. These wavelengths correspond to energies that are above the work function of the metal. There was a QE dependency on voltage, as well as the laser energy used in cleaning. Direct exposure of the cathode to the UV light source also had a cleaning effect on it, possibly removing surface impurities by a photochemical reaction instead of ablation. UV cleaning might prove to be useful in applications where a laser is not readily available for cleaning. The results of this experiment will be useful in determining the optimum conditions for producing high average current electron sources for high energy accelerators and high power light sources.