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.
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
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.
117261868
Symmetry and the Standard Model: Mathematics and Particle Physics
Review of Classical Physics.- A Preview of Particle Physics.- Algebraic Foundations.- First Principles and the Standard Model.- Beyond the Standard Model of Particle Physics.
14822794
A NON-STANDARD STRING EMBEDDING OF E8
An algorithm to systematically and efficiently generate free fermionic heterotic string models was recently introduced.1 This algorithm has been adopted by the Free Fermionic Model Construction (FFMC) program at Baylor University. As its first application, the algorithm is being applied to systematically generate the complete set of free fermionic heterotic string models with untwisted left-moving (worldsheet supersymmetric) sectors, up to continually advancing Layer and Order. Statistical analysis of this study will be reported in the near future. However, in a series of separate notes we will be reporting some of the more interesting models that appear along the way. In this, our first such note, we reveal a different string embedding of E8 than is standard. That is, rather than realize E8 via an SO(16) embedding, 248 = 120 + 128, we realize it via an SU(9) embedding, . This is obtained in a Layer 1, Order 6 model for which modular invariance itself dictates a gravitino sector accompany the gauge sector.
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.
2619788
Obscured and unobscured AGN populations in a hard-X-ray selected sample of the XMDS survey
Aims. Our goal is to probe the populations of obscured and unobscured AGN investigating their optical-IR and X-ray properties as a function of X-ray flux, luminosity and redshift within a hard X-ray selected sample with wide multiwavelength coverage. 
Methods. We selected a sample of 136 X-ray sources detected at a significance of ≥3σ in the 2-10 keV band (F_(2-10) ≳ 10^(-14) erg cm^(-2) s^(-1)) in a ~1 deg^2 area in the XMM Medium Deep Survey (XMDS). The XMDS area is covered with optical photometry from the VVDS and CFHTLS surveys and infrared Spitzer data from the SWIRE survey. Based on the X-ray luminosity and X-ray to optical ratio, 132 sources are likely AGN, of which 122 have unambiguous optical - IR identification. The observed optical and IR spectral energy distributions of all identified sources are fitted with AGN/galaxy templates in order to classify them and compute photometric redshifts. X-ray spectral analysis is performed individually for sources with a sufficient number of counts and using a stacking technique for subsamples of sources at different flux levels. Hardness ratios are used to estimate X-ray absorption in individual weak sources. 
Results. 70% of the AGN are fitted by a type 2 AGN or a star forming galaxy template. We group them together in a single class of "optically obscured" AGN. These have "red" optical colors and in about 60% of cases show significant X-ray absorption (N_H > 10^(22) cm^(-2)). Sources with SEDs typical of type 1 AGN have "blue" optical colors and exhibit X-ray absorption in about 30% of cases. The stacked X-ray spectrum of obscured AGN is flatter than that of type 1 AGN and has an average spectral slope of Γ = 1.6. The subsample of objects fitted by a star forming galaxy template has an even harder stacked spectrum, with Γ ~ 1.2-1.3. The obscured fraction is larger at lower fluxes, lower redshifts and lower luminosities. X-ray absorption is less common than "optical" obscuration and its incidence is nearly constant with redshift and luminosity. This implies that at high luminosities X-ray absorption is not necessarily related to optical obscuration. The estimated surface densities of obscured, unobscured AGN and type 2 QSOs are respectively 138, 59 and 35 deg^(-2) at F > 10^(-14) erg cm^(-2) s^(-1).