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ILC cryogenic systems reference design

Description: A Global Design Effort (GDE) began in 2005 to study a TeV scale electron-positron linear accelerator based on superconducting radio-frequency (RF) technology, called the International Linear Collider (ILC). In early 2007, the design effort culminated in a reference design for the ILC, closely based on the earlier TESLA design. The ILC will consist of two 250 GeV linacs, which provide positron-electron collisions for high energy physics research. The particle beams will be accelerated to their final energy in superconducting niobium RF cavities operating at 2 kelvin. At a length of about 12 km each, the main linacs will be the largest cryogenic systems in the ILC. Positron and electron sources, damping rings, and beam delivery systems will also have a large number and variety of other superconducting RF cavities and magnets, which require cooling at liquid helium temperatures. Ten large cryogenic plants with 2 kelvin refrigeration are envisioned to cool the main linacs and the electron and positron sources. Three smaller cryogenic plants will cool the damping rings and beam delivery system components predominately at 4.5 K. This paper describes the cryogenic systems concepts for the ILC.
Date: January 2008
Creator: Peterson, T. J.; Geynisman, M.; Klebaner, A.; Theilacker, J.; Parma, V. & Tavian, L.
Partner: UNT Libraries Government Documents Department

T-1018 UCLA Spacordion Tungsten Powder Calorimeter

Description: The present experiments at the BNL-RHIC facility are evolving towards physics goals which require the detection of medium energy electromagnetic particles (photons, electrons, neutral pions, eta mesons, etc.), especially at forward angles. New detectors will place increasing demands on energy resolution, hadron rejection and two-photon resolution and will require large area, high performance electromagnetic calorimeters in a variety of geometries. In the immediate future, either RHIC or JLAB will propose a facility upgrade (Electron-Ion Collider, or EIC) with physics goals such as electron-heavy ion collisions (or p-A collisions) with a wide range of calorimeter requirements. An R and D program based at Brookhaven National Laboratory has awarded the group funding of approximately $110,000 to develop new types of calorimeters for EIC experiments. The UCLA group is developing a method to manufacture very flexible and cost-effective, yet high quality calorimeters based on scintillating fibers and tungsten powder. The design and features of the calorimeter can be briefly stated as follows: an arbitrarily large number of small diameter fibers (< 0.5 mm) are assembled as a matrix and held rigidly in place by a set of precision screens inside an empty container. The container is then back-filled with tungsten powder, compacted on a vibrating table and infused with epoxy under vacuum. The container is then removed. The resulting sub-modules are extremely uniform and achieve roughly the density of pure Lead. The sub-modules are stacked together to achieve a final detector of the desired shape. There is no dead space between sub-modules and the fibers can be in an accordion geometry bent to prevent 'channeling' of the particles due to accidental alignment of their track with the module axis. This technology has the advantage of being modular and inexpensive to the point where the construction work may be divided among groups the size ...
Date: November 16, 2011
Creator: Trentalange, Stephen; Tsai, Oleg; Igo, George; Huang, Huan; Pan, Yu Xi; Dunkelberger, Jay et al.
Partner: UNT Libraries Government Documents Department

T-1020 NaI crystal test for DM-Ice

Description: This is a memorandum of understanding between the Fermi National Accelerator Laboratory (Fermilab) and the experiments of the NaI Crystal Test for DM-Ice from the University of Wisconsin who have committed to participate in detector tests to be carried out during the 2011-2012 Fermilab Neutrino program. The memorandum is intended primarily for the purpose of recording expectations for budget estimates and work allocations for Fermilab, the funding agencies and the participating institutions. It reflects an arrangement that currently is satisfactory to the parties; however, it is recognized and anticipated that changing circumstances of the evolving research program will necessitate revisions. The parties agree to modify this memorandum to reflect such required adjustments. Actual contractual obligations will be set forth in separate documents. The DM-Ice collaboration is designing a sodium-iodide (NaI) based detector for a direct dark matter search. The detectors should have low readout noise and background levels to carry out a sensitive search. A 17-kg version of the experiment is running at the South Pole, 2500 m deep in the Antarctic ice, and a large scale experiment is currently being designed. One of the keys to the success of the experiment is to have a good understanding of the background levels intrinsic in the NaI detectors. To measure the background level, the detectors have to be shielded against cosmic rays. The lead shielding used for DAMIC in the Minos Underground Areas is a well-suited location for this test since it offers enough overburden to shield against cosmic rays, lead shielding, and experimental infrastructure. The goal of the test is to assess the background levels in the detector and to assess the characteristics of phosphorescence induced by muons and 100 keV-3 MeV gamma rays.
Date: November 3, 2011
Creator: Maruyama, Reina; Heeger, Karsten; Pierpoint, Zachary; Pettus, Walter; Broerman, Benjamin; Hilgenberg, Chris et al.
Partner: UNT Libraries Government Documents Department

T-1025 IU SciBath-768 detector tests in MI-12

Description: This is a memorandum of understanding between the Fermi National Accelerator Laboratory (Fermilab) and the experimenters of Department of Physics and Center for Exploration of Energy and Matter, Indiana University, who have committed to participate in detector tests to be carried out during the 2012 Fermilab Neutrino program. The memorandum is intended solely for the purpose of recording expectations for budget estimates and work allocations for Fermilab, the funding agencies and the participating institutions. it reflects an arrangement that currently is satisfactory to the parties; however, it is recognized and anticipated that changing circumstances of the evolving research program will necessitate revisions. The parties agree to modify this memorandum to reflect such required adjustments. Actual contractual obligations will be set forth in separate documents. The experimenters propsoe to test their prototype 'SciBat-768' detector in the MI-12 building for 3 months (February-April) in Spring 2012. The major goal of this effort is to measure or limit the flux of beam-induced neutrons in a far-off-axis (> 45{sup o}) location of the Booster Neutrino Beamline (BNB). This flux is of interest for a proposed coherent neutral-current neutrino-argon elastic scattering experiment. A second goal is to collect more test data for the SciBath-768 to enable better understanding and calibration of the device. The SciBath-768 detector successfully ran for 3 months in the MINOS Underground Area in Fall 2011 as testbeam experiment T-1014 and is currently running above ground in the MINOS service building. For the run proposed here, the experiments are requesting: space in MI-12 in which to run the SciBath detector during February-April 2012 while the BNB is operating; technical support to help with moving the equipment on site; access to power, internet, and accelerator signals; and a small office space from which to run and monitor the experiment.
Date: February 11, 2012
Creator: Tayloe, Rex; Cooper, R.; Garrison, L.; Thornton, T.; Rebenitsch, L.; U., /Indiana et al.
Partner: UNT Libraries Government Documents Department

Accelerator/Experiment Operations - FY 2011

Description: This Technical Memorandum (TM) summarizes the Fermilab accelerator and accelerator experiment operations for FY 2011. It is one of a series of annual publications intended to gather information in one place. In this case, the information concerns the FY 2011 Run II at the Tevatron Collider, the MINOS and MINERvA experiments using the Main Injector Neutrino Beam (NuMI), the MiniBooNE experiment running in the Booster Neutrino Beam (BNB), and the Meson Test Beam (MTest) activities in the 120 GeV external Switchyard beam (SY120).
Date: November 1, 2011
Creator: Adamson, P.; Bernardi, G.; Casarsa, M.; Coleman, R.; Denisov, D.; Dixon, R. et al.
Partner: UNT Libraries Government Documents Department

Calculation of acceptance of high intensity superconducting proton linac for Project X

Description: Project-X is the proposed high intensity proton facility to be built at Fermilab, US. Its Superconducting Linac, to be used at first stage of acceleration, will be operated in continuous wave (CW) mode. The Linac is divided into three sections on the basis of operating frequencies & six sections on the basis of family of RF cavities to be used for the acceleration of beam from 2.5 MeV to 3 GeV. The transition from one section to another can limit the acceptance of the Linac if these are not matched properly. We performed a study to calculate the acceptance of the Linac in both longitudinal and transverse plane. Investigation of most sensitive area which limits longitudinal acceptance and study of influence of failure of beam line elements at critical position, on acceptance are also performed.
Date: March 1, 2011
Creator: Saini, A.; Ranjan, K.; U., /Delhi; Solyak, N.; Mishra, S.; Yakovlev, V. et al.
Partner: UNT Libraries Government Documents Department

Calculation of Residual Dose Around Small Objects Using Mu2e Target as an Example

Description: The MARS15 code provides contact residual dose rates for relatively large accelerator and experimental components for predefined irradiation and cooling times. The dose rate at particular distances from the components, some of which can be rather small in size, is calculated in a post Monte-Carlo stage via special algorithms described elsewhere. The approach is further developed and described in this paper.
Date: September 1, 2011
Creator: Pronskikh, V.S.; Leveling, A.F.; Mokhov, N.V.; Rakhno, I.L.; /Fermilab; Aarnio, P. et al.
Partner: UNT Libraries Government Documents Department

Cavity loss factors of non-relativistic beams for Project X

Description: Cavity loss factor calculation is an important part of the total cryolosses estimation for the super conductive (SC) accelerating structures. There are two approaches how to calculate cavity loss factors, the integration of a wake potential over the bunch profile and the addition of loss factors for individual cavity modes. We applied both methods in order to get reliable results for non-relativistic beam. The time domain CST solver was used for a wake potential calculation and the frequency domain HFSS code was used for the cavity eigenmodes spectrum findings. Finally we present the results of cavity loss factors simulations for a non-relativistic part of the ProjectX and analyze it for various beam parameters.
Date: March 1, 2011
Creator: Lunin, A.; Yakovlev, V.; Kazakov, S. & /Fermilab
Partner: UNT Libraries Government Documents Department

The Capabilities of the upgraded MIPP experiment with respect to Hypernuclear physics

Description: We describe the state of analysis of the MIPP experiment, its plans to upgrade the experiment and the impact such an upgraded experiment will have on hypernuclear physics. The upgraded MIPP experiment is designed to measure the properties of strong interaction spectra form beams {pi}{sup {+-}}, K{sup {+-}}, and p{sup {+-}}, for momenta ranging from 1 GeV/c to 120 GeV/c. The layout of the apparatus in the data taken so far can be seen in Figure 1. The centerpiece of the experiment is the time projection chamber, which is followed by the time of flight counter, a multi-cell Cerenkov detector and the RICH detector. The TPC can identify charged particles with momenta less than 1 GeV/c using dE/dx, the time of flight will identify particles below approximately 2 GeV/c, the multi-cell Cerenkov detector is operational from 2.5 GeV/c to 14 GeV/c and the RICH detector can identify particles up to 120 GeVc. Following this is an EM and hadronic calorimeter capable of detecting forward going neutrons and photons. The experiment has been busy analyzing its data taken on various nuclei and beam conditions. The table 2 shows the data taken by MIPP I to date. We have almost complete acceptance in the forward hemisphere in the lab using the TPC. The reconstruction capabilities of the TPC can be seen in Figure 3. The particle identification capabilities of the TPC can be seen in Figure 4. The time of flight system provides further measurement of the particles with momenta less than 2 GeV/c. Figure 5 shows the time of flight data where a kaon peak is clearly visible.
Date: January 1, 2012
Creator: Raja, Rajendran
Partner: UNT Libraries Government Documents Department

Dark matter limits froma 15 kg windowless bubble chamber

Description: The COUPP collaboration has successfully used bubble chambers, a technology previously applied only to high-energy physics experiments, as direct dark matter detectors. It has produced the world's most stringent spin-dependent WIMP limits, and increasingly competitive spin-independent limits. These limits were achieved by capitalizing on an intrinsic rejection of the gamma background that all other direct detection experiments must address through high-density shielding and empirically-determined data cuts. The history of COUPP, including its earliest prototypes and latest results, is briefly discussed in this thesis. The feasibility of a new, windowless bubble chamber concept simpler and more inexpensive in design is discussed here as well. The dark matter limits achieved with a 15 kg windowless chamber, larger than any previous COUPP chamber (2 kg, 4 kg), are presented. Evidence of the greater radiopurity of synthetic quartz compared to natural is presented using the data from this 15 kg device, the first chamber to be made from synthetic quartz. The effective reconstruction of the three-dimensional positions of bubbles in a highly distorted optical field, with ninety-degree bottom lighting similar to cloud chamber lighting, is demonstrated. Another innovation described in this thesis is the use of the sound produced by bubbles recorded by an array of piezoelectric sensors as the primary means of bubble detection. In other COUPP chambers, cameras have been used as the primary trigger. Previous work on bubble acoustic signature differentiation using piezos is built upon in order to further demonstrate the ability to discriminate between alpha- and neutron-induced events.
Date: December 1, 2010
Creator: Szydagis, Matthew Mark & U., /Chicago
Partner: UNT Libraries Government Documents Department

The decay constants fDs and fD+ form lattice QCD

Description: Recent calculations of the decay constants in lattice QCD are reviewed and compared to experiment. The decay constants are tabulated in Table 2 and plotted in Figure 2. The most precise f{sub Ds} value is from HPQCD. It is about 2{sigma} higher than their previous result. The change is due to a more precise determination of the lattice spacing and better tuning of the quark masses. They have updated f{sub D+} using the new f{sub Ds} and their older f{sub Ds}/f{sub D+} ratio which is expected to be less sensitive to mistuning of the lattice spacing and masses. The preliminary FNAL/MILC f{sub Ds} value is about 1.4{sigma} higher than the HPQCD result but with a larger error. The f{sub D+} values, however, are in better agreement. FNAL/MILC expect to finalize their results once the charm quark mass tuning is complete. The two flavor ETM f{sub D+} value is about 1.6{sigma} lower than the HPQCD value while f{sub Ds} is in better agreement. It is not clear how much of the difference is from neglecting the strange sea quark, given the errors. Lattice and experiment differ most significantly for f{sub Ds}. Figure 3 shows Kronfeld's (updated) history of f{sub Ds}. The yellow bands depict the evolution of the experimental average while the three-flavor lattice average is shown in grey. The right-hand scale and green lines show the differences in sigmas. The 3.8{sigma} discrepancy around t {approx} 2 provoked the 'f{sub Ds} puzzle'. That discrepancy has now shrunk to 1.6{sigma}. Future lattice and experiment will be decisive.
Date: March 1, 2011
Creator: Simone, James N
Partner: UNT Libraries Government Documents Department

Demonstration of a real-time interferometer as a bunch-lenght monitor in a high-current electron beam accelerator

Description: A real-time interferometer (RTI) has been developed to monitor the bunch length of an electron beam in an accelerator. The RTI employs spatial autocorrelation, reflective optics, and a fast response pyro-detector array to obtain a real-time autocorrelation trace of the coherent radiation from an electron beam thus providing the possibility of online bunch-length diagnostics. A complete RTI system has been commissioned at the A0 photoinjector facility to measure sub-mm bunches at 13 MeV. Bunch length variation (FWHM) between 0.8 ps (-0.24 mm) and 1.5 ps (-0.45 mm) has been measured and compared with a Martin-Puplett interferometer and a streak camera. The comparisons show that RTI is a viable, complementary bunch length diagnostic for sub-mm electron bunches.
Date: March 1, 2012
Creator: Thangaraj, J.; Thurman-Keup, R.; Ruan, J.; Johnson, A.S.; Lumpkin, A; Santucci, J. et al.
Partner: UNT Libraries Government Documents Department

A Dependence Study of $\Xi^{*0}$ and $\bar{\Xi}^{*0}$ in 250 GeV/c $\pi^-$. $K^-$ -nucleon Interactions

Description: A direct measurement of the mass number (A) dependence of the production of the hyperon {Xi}*{sup 0} and its opposite {bar {Xi}}*{sup 0} in {pi}{sup -}, K{sup -} beam-nucleon interactions at 250 GeV/c is reported. The data derive from the experiment E769 at Fermilab. The results were obtained for different targets: Be, Al, Cu and W. It was observed the data are found to be well described by the parametrization {sigma}{sub A} = {sigma}{sub 0}A{sup {alpha}}, {alpha} being calculated for different beams. The results obtained are compared with those results of E769 experiment. The results shown here are preliminary.
Date: April 1, 2005
Creator: Seixas de Rezende, Fabio Antonio & /Rio de Janeiro, CBPF
Partner: UNT Libraries Government Documents Department

Depleted argon from underground sources

Description: Argon is a powerful scintillator and an excellent medium for detection of ionization. Its high discrimination power against minimum ionization tracks, in favor of selection of nuclear recoils, makes it an attractive medium for direct detection of WIMP dark matter. However, cosmogenic {sup 39}Ar contamination in atmospheric argon limits the size of liquid argon dark matter detectors due to pile-up. The cosmic ray shielding by the earth means that Argon from deep underground is depleted in {sup 39}Ar. In Cortez Colorado a CO{sub 2} well has been discovered to contain approximately 500ppm of argon as a contamination in the CO{sub 2}. In order to produce argon for dark matter detectors we first concentrate the argon locally to 3-5% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation. The N{sub 2} and He will be removed by continuous cryogenic distillation in the Cryogenic Distillation Column recently built at Fermilab. In this talk we will discuss the entire extraction and purification process; with emphasis on the recent commissioning and initial performance of the cryogenic distillation column purification.
Date: September 1, 2011
Creator: Back, H.O.; U., /Princeton; Alton, A.; Coll., /Augustana U.; Calaprice, F.; Galbiati, C. et al.
Partner: UNT Libraries Government Documents Department

Design and Fabrication of a Single-Aperture 11T Nb3Sn Dipole Model for LHC Upgrades

Description: The planned upgrade of the LHC collimation system includes additional collimators to be installed in the dispersion suppressor areas of points 2, 3 and 7. To provide the necessary longitudinal space for the collimators, a replacement of 8.33 T Nb-Ti LHC main dipoles with 11 T dipoles based on Nb{sub 3}Sn superconductor compatible with the LHC lattice and main systems is being considered. To demonstrate this possibility FNAL and CERN have started a joint program to develop a 2 m long single-aperture dipole magnet with the nominal field of 11 T at {approx}11.85 kA current and 60 mm bore. This paper describes the demonstrator magnet magnetic and mechanical designs and analysis, coil fabrication procedure. The Nb{sub 3}Sn strand and cable parameters and test results are also reported.
Date: November 28, 2011
Creator: Andreev, N.; Apollinari, G.; Barzi, E.; Bossert, R.; Nobrega, F.; Novitski, I. et al.
Partner: UNT Libraries Government Documents Department

D0 Silicon Upgrade: Wedge Heat Transfer

Description: The Silicon Mechanical group has submitted a wedge drawing to the Fermilab Analysis Group (Zhijing Tang) to determine the temperature distribution in the ladder during detector operation. Heat transfer by convection and radiation is assumed negligible and two dimensional FEA conduction solutions were performed. The heat flux at the SVX II chip region is assumed to be 8.359 mW/mm{sup 2} which corresponds to roughly 0.48 W per SVX II chip. The heat flux in the region of the transceiver is assumed 5.556 mW/mm{sup 2}, corresponding to 2.56 W in this region. Total heat load of the wedge is assumed to be 10.24 W. The wedge submitted for analysis is shown. The multi-chip module (MCM) is mounted on a beryllium plate which serves to carry the heat load of the chips and the transceiver to the cooling channel. Adhesive thermal conductivity is 1.6 W/m-K, based on the published value of the selected adhesive. Actual measurements of thermally conductive adhesives indicate that the assumed 1.6 W/m-K is high. Experience gained in measuring adhesive thermal conductivity indicates 0.9-1.2 W/m-K as a more reasonable number to use. The effect of the uncertainty of the adhesive thermal conductivity on silicon temperature is discussed.
Date: September 19, 1994
Creator: Ratzmann, Paul
Partner: UNT Libraries Government Documents Department

CP violating anomalous top-quark coupling in p$\bar{p}$ collision at $\sqrt{s}=1.96$ TeV

Description: We conduct the first study of the T-odd correlations in tt events produced in p{bar p} collision at the Fermilab Tevatron collider that can be used to search for CP violation. We select events which have lepton+jets final states to identify t{bar t} events and measure counting asymmetries of several physics observables. Based on the result, we search the top quark anomalous couplings at the production vertex at the Tevatron. In addition, Geant4 development, photon identification, the discrimination of a single photon and a photon doublet from {pi}{sup 0} decay are discussed in this thesis.
Date: April 1, 2011
Creator: Lee, Sehwook & U., /Iowa State
Partner: UNT Libraries Government Documents Department

CP Violation in D0-D0bar Mixing and Electric Dipole Moments in SUSY Alignment Models

Description: We report on a study of CP Violation in D{sup 0}-{bar D}{sup 0} mixing and Electric Dipole Moments in the framework of supersymmetric alignment models. Both classes of observables are strongly suppressed in the Standard Model and highly sensitive to new sources of flavor and CP violation that can be present in models of New Physics. Supersymmetric alignment models generically predict large non-standard effects in D{sup 0}-{bar D}{sup 0} mixing and we show that visible CP violation in D{sup 0}-{bar D}{sup 0} mixing implies lower bounds for the EDMs of hadronic systems, like the neutron EDM and the mercury EDM, in the reach of future experimental sensitivities. We also give updated constraints on the mass insertions of the Minimal Supersymmetric Standard Model using the current data on D{sup 0}-{bar D}{sup 0} mixing.
Date: May 1, 2011
Creator: Altmannshofer, Wolfgang
Partner: UNT Libraries Government Documents Department


Description: Cross-sections are presented for 58 GeV {pi}, K, and p on a wide range of nuclear targets. These cross-sections are essential for determining the neutrino flux in measurements of neutrino cross-sections and oscillations. The E907 Main Injector Particle Production (MIPP) experiment at Fermilab is a fixed target experiment for measuring hadronic particle production using primary 120 GeV/c protons and secondary {pi}, K, and p beams. The particle identification is made by dE/dx in a time projection chamber, and by time-of-flight, differential Cherenkov and ring imaging Cherenkov detectors, which together cover a wide range of momentum from 0.1 GeV/c up to 120 GeV/c. MIPP targets span the periodic table, from hydrogen to uranium, including beryllium and carbon. The MIPP has collected {approx} 0.26 x 10{sup 6} events of 58 GeV/c secondary particles produced by protons from the main injector striking a carbon target.
Date: December 1, 2009
Creator: Gunaydin, Yusuf Oguzhan & U., /Iowa
Partner: UNT Libraries Government Documents Department