73549079
AN FPGA BASED CONTROLLER FOR THE MICE TARGET
The MICE experiment [1], uses a beam of low energy muons to test the feasibility of ionization cooling. This beam is derived parasitically from the ISIS accelerator at the Rutherford Appleton Laboratory. A target mechanism has been developed that rapidly inserts a small titanium target into the circulating proton beam immediately prior to extraction without unduly disturbing the primary ISIS beam. The original control electronics for the MICE target was based upon an 8-bit PIC. Although this system was fully functional it did not provide the necessary IO to permit full integration of the target electronics onto the MICE EPICS system. A three phase program was established to migrate both the target control and DAQ electronics from the original prototype onto a fully integrated FPGA system that is capable of interfacing with EPICS through a local PC. This paper discusses this upgrade program, the motivation behind it and the performance of the upgraded target controller.
126074679
The mice target
122078935
The LAGUNA project: Towards the giant liquid based detectors for proton decay searches and for low energy neutrino astrophysics
Jan Kisiel Institute of Physics, University of Silesia Uniwersytecka 4, 40-007 Katowice, Poland E-mail: Jan.Kisiel@us.edu.pl D. Angusa, A. Arigab, D. Autieroc, A. Apostud, A. Badertschere, T. Bennetf, G. Bertolag, P.F. Bertolag, O. Besidah, A. Bettinii, C. Boothf, J.L. Bornec, I. Brancusd, W. Bujakowskij, J.E. Campagnec, G. Cata-Danild, F. Chipesiud, M. Chorowskik, J. Crippsf, A. Curionie, S. Davidsonc, Y.R.A Declaisc, U. Drostg, O. Duliul, J. Dumarchezc, T. Enqvistm, A. Ereditatob, F. v Feilitzschn, H. Fynboo, T. Gamblef, G. Galvaninp, A. Gendottie, W. Gizickik, M. GogerNeffn, U. Grassling, D. Gurneyq, M. Hakalar, S. Hannestado, M. Haworthq, A. Jipal, F. Jugetb, T. Kalliokoskis, S. Katsanevasc, M. Keent, I.Kreslob, V. Kudryastevf, P. Kuusiniemim, L. Labargau, T. Lachenmaiern, J.C. Lanfranchin, I. Lazanul, T. Lewken, K. Loom, P. Lightfootf, M. Lindnerv, P. Lombardiw, A. Longhinh, J. Maalampis, M. Marafinic, A. Marchionnie, R.M. Margineanud, A. Markiewiczx, T. Marrodan-Undagoitan, J.E. Marteauc, R. Matikainenr, Q. Meindln, M. Messinab, J.W. Mietelskiy, B. Mitricad, A. Mordasinig, L. Moscah, U. Moserb, G. Nuijtenr, L. Oberauern, A. Oprinad, S. Palingf, S. Pascolia, T. Patzakc, M. Pectud, Z. Pileckij, F. Piquemalc, W. Potzeln, W. Pytelx, M. Raczynskix, G. Raffeltz, G. Ranucciw, G. Ristainop, M. Robinsonf, R. Rogersq, J. Roinistor, M. Romanai, E. RondioA, B. Rossib, A. Rubbiae, Z. Sadeckix, C. Saenzi, A. Saftoiud, J. Salmelainenr, O. Simal, J. Slizowskij, K. Slizowskij, J. SobczykB, N. Spoonerf, S. Stoicad, J. Suhonens, R. SulejA, M. Szarskay, T. SzeglowskiC, M. Temussip, J. Thompsonq, L. Thompsonf, W.H. Trzaskas, M. Tippmannn, A. Tonazzoc, K. Urbanczykj, G. Vasseurh, A. Williamst, J. Wintern, K. Wojtuszewskaj, M. Wurmn, A. Zalewskay, M. Zampaoloc, M. Zitoh
120745615
Simulation of neutron background for future large-scale particle dark matter detectors
Abstract Simulations of the neutron background for future large-scale particle dark matter detectors are presented. Neutrons were generated in rock and detector elements via spontaneous fission and (α,n) reactions, and by cosmic-ray muons. The simulation techniques and results are discussed in the context of the expected sensitivity of a generic liquid xenon dark matter detector. Methods of neutron background suppression are investigated. A sensitivity of 10 −9 –10 −10  pb to WIMP-nucleon interactions can be achieved by a tonne-scale detector.
119184333
Power spectra beyond the slow roll approximation in theories with non-canonical kinetic terms
We derive analytical expressions for the power spectra at the end of inflation in theories with two inflaton fields and non-canonical kinetic terms. We find that going beyond the slow-roll approximation is necessary and that the nature of the non-canonical terms have an important impact on the final power spectra at the end of inflation. We study five models numerically and find excellent agreement with our analytical results. Our results emphasise the fact that going beyond the slow-roll approximation is important in times of high-precision data coming from cosmological observations.
1038107
Spontaneous CP Violation in Models with Anomalous U(1)
We examine a class of Froggatt-Nielsen models with an anomalous U(1) as the flavor dependent symmetry. Anomaly cancellation and unbroken supersymmetry impose constraints on the U(1)_X charges of the fermions and the vacuum expectation values of the symmetry-breaking scalars. We show by example that it is possible to find models that reproduce the observed masses and mixings of the standard model fermions, and exhibit a realistic amount of CP violation.
12334845
Stringent phenomenological investigation into heterotic string optical unification
For the weakly coupled heterotic string (WCHS) there is a well-known factor of 20 conflict between the minimum string coupling unification scale, {lambda}{sub H}{approx}5x10{sup 17} GeV, and the projected minimal supersymmetric standard model (MSSM) gauge coupling unification scale, {lambda}{sub U}{approx}2.5x10{sup 16} GeV, assuming an intermediate scale desert (ISD). From a bottom-up approach, renormalization effects of intermediate scale MSSM-charged exotics (ISME), which are endemic to quasirealistic string models, can resolve this issue by pushing the MSSM scale up to the string scale. However, for a generic string model, this implies that the projected {lambda}{sub U} unification under the ISD assumption is accidental. If the true unification scale is {lambda}{sub H} > or approx. 5.0x10{sup 17} GeV, is it possible that an illusionary unification at {lambda}{sub U}=2.5x10{sup 17} GeV in the ISD scenario is not accidental? (This is an issue recently raised again by Binetruy et al..) Optical unification suggests that {lambda}{sub U} might not be accidental. Through its ISME constraints, optical unification offers a mechanism whereby a generic MSSM scale {lambda}{sub U}<{lambda}{sub H} is guaranteed. A WCHS model was recently constructed that could yield optical unification, depending on the availability of anomaly-cancelling D- and F-flat directions that meet optical unification ISME more » requirements. We report the results of a systematic investigation of the optical unification properties of a subset of flat directions of this model that are stringently flat. Stringent flat directions do not require significant fine-tuning and can be easily guaranteed to be F-flat to all finite order (or to at least a given finite order consistent with electroweak scale supersymmetry breaking). They are the likely roots of more complicated (and arguably, more finely tuned) flat directions. To realize optical unification, a flat direction must keep all exotic triplets and doublets massless down to an intermediate mass scale, except for three extra pairs of Higgs which must acquire MSSM (or higher) scale mass. Additionally, six out of seven pairs of exotic hypercharged non-Abelian singlets must acquire MSSM (or higher) scale mass, while the remaining pair remains massless down to the intermediate scale. Our investigation revealed that the best stringent directions could induce MSSM scale or higher mass to at most three of the six pairs of exotic singlets, and to only two out of three pairs of exotic Higgs. Each of these stringent flat directions keeps all of the exotic triplets and remaining exotic doublets massless down to an intermediate scale. Thus, some fine-tuning away from stringent flat directions is necessary, if it is possible for an additional three pairs of exotic hypercharged singlets and one more pair of extra Higgs to become MSSM scale massive. Future research may indicate if such flat directions exist. This paper is a product of the 2003-2004 NSF REU program at Baylor University. « less
11483140
Heterotic string optical unification
The lower limit to string coupling unification in weakly coupled heterotic strings was shown by Kaplunovsky to be around Lambda_H ~ 5 x 10^{17} GeV. In contrast, under the scenario of an intermediate scale desert, the SU(3)_C x SU(2)_L x U(1)_Y ([321]) Minimal Supersymmetric Standard Model (MSSM) unification scale is Lambda_U ~ 2.5 x 10^{16} GeV. Optical unification was proposed by Giedt as a robust mechanism for relating these two scales. In this mechanism, intermediate scale MSSM-charged exotic particles effect running couplings like a diverging lens, always producing a ``virtual'' image of the string unification point between the string scale and the exotic particle mass scale. A heterotic string model that offers the potential to realize optical unification was recently constructed. This paper reports the initial results of an investigation into the possibility of optical unification realization in this model. This paper is a product of the NSF REU program at Baylor University and is based on a talk presented at the Second International Conference on String Phenomenology, Durham, England, 29 July - 4 August, 2003.
125332655
Performance of the ATLAS tau trigger with 7 TeV collision data at the LHC
Tau leptons are a fundamental ingredient in the discovery of new physics at the LHC. The reconstruction of hadronic tau decays at the trigger level, although a very challenging task in protonproton collision environments, allows us to double the sample of tau decays collected, and provides additional discovery power to final states which include tau leptons. In this contribution we show the understanding of the tau trigger system using data collected with the ATLAS detector at the LHC in proton-proton collisions at a center-of-mass energy of 7 TeV. We present the most relevant quantities used in the different stages of the trigger selection, and the trigger efficiencies as a function of ET using tau-like QCD events passing the offline reconstruction and identification selection.
16595190
Grover's Quantum Search Algorithm and Free Fermionic Heterotic Models
Given an efficient and systematic method for generating input sets for free fermionic heterotic model building we consider what the realistic bounds are for a statistical analysis of the free fermionic Landscape with a classical computer. We then consider what kind of improvement could be expected on a quantum computer. We do outline the basic structure of the relevant quantum algorithms, but we do not detail the construction of the oracle which would be involved in the calculations.