February 1996 arXiv papers — page 11

Andrei Afanasev, Alexander Glamazdin

We analyse an effect of electron Fermi motion at atomic shells on the accuracy of electron beam polarization measurements with a Möller polarimeter operating in a double--arm mode. It is demonstrated that the effect can result in either {\it increase} or {\it decrease} of the measured polarization depending on the detector positions. The effect is simulated

G. Rudolph, T. Tok, I. Volobuev

We present a class of solutions in Einstein-Yang-Mills-systems with arbitrary gauge groups and space-time dimensions, which are symmetric under the action of the group of spatial rotations. Our approach is based on the dimensional reduction method for gauge and gravitational fields and relates symmetric EYM-solutions to certain solutions of two-dimensional E

A. Chamorro, K. S. Virbhadra

The energy associated with a static and spherically symmetric charged dilaton black hole is obtained for arbitrary value of the coupling parameter (which regulates the strength of the coupling of the dilaton to the Maxwell field) $β$. The energy distribution depends on $β$, whereas the total energy is independent of this and is given by the mass parameter of

Edward P. Osipov

We consider the (real) nonlinear wave equation $$\Box u + m^2 u + λu^3 = 0, \quad m > 0, \quad λ> 0, $$ on four-\-dimensional Minkowski space. We introduce the complex structure and show that the (nonlinear) operator of dynamics, the wave and scattering operators define complex analytic maps on the space of initial Cauchy data with finite energy. In other wo

P. Exner, S. A. Vugalter

Consider the Laplacian in a straight planar strip of width $\,d\,$, with the Neumann boundary condition at a segment of length $\,2a\,$ of one of the boundaries, and Dirichlet otherwise. For small enough $\,a\,$ this operator has a single eigenvalue $\,ε(a)\,$; we show that there are positive $\,c_1,c_2\,$ such that $\,-c_1 a^4 \le ε(a)- \left(π/ d\right)^2

Peter Kopietz

The disorder averaged single-particle Green's function of electrons subject to a time-dependent random potential with long-range spatial correlations is calculated by means of bosonization in arbitrary dimensions. For static disorder our method is equivalent with conventional perturbation theory based on the lowest order Born approximation. For dynamic d

Beatriz Boechat, Andreia Saguia, Mucio Continentino

We study disordered spin-1 quantum chains with random exchange and biquadratic interactions using a real space renormalization group approach. We find that the dimerized phase of the pure biquadratic model is unstable and gives rise to a random singlet phase in the presence of weak disorder. In the Haldane region of the phase diagram we obtain a quite differ

Per Bak, Maya Paczuski

It is usually believed that Darwin's theory leads to a smooth gradual evolution, so that mass extinctions must be caused by external shocks. However, it has recently been argued that mass extinctions arise from the intrinsic dynamics of Darwinian evolution. Species become extinct when swept by intermittent avalanches propagating through the global ecolog

Maya Paczuski, Kai Nagel

Phantom traffic jams may emerge ``out of nowhere'' from small fluctuations rather than being triggered by large, exceptional events. We show how phantom jams arise in a model of single lane highway traffic, which mimics human driving behavior. Surprisingly, the optimal state of highest efficiency, with the largest throughput, is a critical state with

Albert-László Barabás

Invasion bond percolation (IBP) is mapped exactly into Prim's algorithm for finding the shortest spanning tree of a weighted random graph. Exploring this mapping, which is valid for arbitrary dimensions and lattices, we introduce a new IBP model that belongs to the same universality class as IBP and generates the minimal energy tree spanning the IBP clus

R. Berkovits, Y. Ashkenazy, L. P. Horwitz, J. Levitan

The spectrum of a double well constructed of a square barrier embedded in an infinite well is analyzed. Level statistics for levels slightly above the barrier show signs of Wigner statistics usually associated with quantum chaos. The correspondence with Wigner statistics improves when an ensemble of systems with slightly different barrier heights is taken, p

Gongwen Peng, Jens-Uwe Sommer, Alexander Blumen

We investigate numerically using the bond--fluctuation model the adsorption of a random AB--copolymer at the interface between two solvents. From our results we infer several scaling relations: the radius of gyration of the copolymer in the direction perpendicular to the interface ($R_{gz}$) scales with $χ$, the interfacial selectivity strength, as $R_{gz}=N

Atsushi Yamagata

We perform Monte Carlo simulations of the hard-sphere lattice gas on the body-centred cubic lattice with nearest neighbour exclusion. We get the critical exponents, $β/ν= 0.311(8)$ and $γ/ν= 2.38(2)$, where $β$, $γ$, and $ν$ are the critical exponents of the staggered density, the staggered compressibility, and the correlation length, respectively. The value

S. Graffi, A. Martinez

We give through pseudodifferential operator calculus a proof that the quantum dynamics of a class of infinite harmonic crystals becomes ergodic and mixing with respect to the quantum Gibbs measure if the classical infinite dynamics is respectively ergodic and mixing with respect to the classical infinite Gibbs measure. The classical ergodicity and mixing pro

Yoshiyuki Y. Yamaguchi

Temporal evolutions toward thermal equilibria are numerically investigated in a Hamiltonian system with many degrees of freedom which has second order phase transition. Relaxation processes are studied through local order parameter, and slow relaxations of power type are observed at the critical energy of phase transition for some initial conditions. Numeric

K. Saermark, Y. Ashkenazy, J. Levitan, M. Lewkowicz

We show that a simple non-linear system of ordinary differential equations may possess a time varying attractor dimension. This indicates that it is infeasible to characterize EEG and MEG time series with a single time global dimension. We suggest another measure for the description of non-stationary attractors.

P. Hoeflich, A. Khokhlov, J. C. Wheeler, K. Nomoto

From the spectra and light curves it is clear that SNIa are thermonuclear explosions of white dwarfs. However, details of the explosion are highly under debate. Here, we present detailed models which are consistent with respect to the explosion mechanism, the optical and infrared light curves (LC), and the spectral evolution. This leaves the description of t

A. Bykov, P. Meszaros

In energetic nonthermal sources such as gamma-ray bursts, AGN or galactic jet sources, etc., one expects both relativistic and transrelativistic shocks acompanied by violent motions of moderately relativistic plasma. We present general considerations indicating that these sites are electron and positron accelerators leading to a modified power law spectrum.

R. Ansari, M. Auriere, P. Baillon, A. Bouquet

A status report of the microlensing search by the pixel method in the direction of M31, on the 2 meter telescope at Pic du Midi is given. Pixels are stable to a level better than 0.5%. Pixel variations as small as 0.02 magnitude can clearly be detected.

Raul Jimenez, Paolo Padoan

We present a new method to compute stellar ages in Globular Clusters (GC) that is ten times more precise than the traditional isochrone fitting procedure. The method relies on accurate stellar evolutionary tracks and on photometry for GCs complete down to the main sequence, and it is based on counting number of stars in two different regions of the CMD: the

Lori M. Lubin, Marc Postman

We present a study of the surface density profiles of the clusters of galaxies from the Palomar Distant Cluster Survey (Postman et al. 1996). The survey contains a total of 79 clusters of galaxies, covering the estimated redshift range of $0.2 \simless z \simless 1.2$. We have analyzed the richest clusters in this sample and find that the typical Palomar clu

P. Andreani, L. Pizzo, G. Dall'Oglio, N. Whyborn

We report on observations of the Sunyaev-Zeldovich effect towards X-ray ROSAT clusters taken with a double channel (1.2 and 2 mm) photometer installed at the focus of the 15m SEST antenna in Chile. This paper describes the first results obtained for the high-z clusters S1077, A2744 and S295. Marginal detections were found for A2744 and at 1 mm for S1077. We

Bianca Garilli, Dario Bottini, Dario Maccagni, Luis Carrasco

We report the first results of a long term program aimed at investigating the photometric properties of the cores of Abell and X-ray selected (EMSS, \cite{emss}) clusters of galaxies. We observed 77 clusters of galaxies in the redshift range $0.05\leq z \leq 0.25$ in the Gunn $g$, $r$ and $i$ filters: in this paper we present the data on 59 clusters with goo

Michael A. Janssen, Douglas Scott, Martin White, Michael D. Seiffert

Fundamental information about the Universe is encoded in anisotropies of the Cosmic Microwave Background (CMB) radiation. To make full use of this information, an experiment must image the entire sky with the angular resolution, sensitivity, and spectral coverage necessary to reach the limits set by cosmic variance on angular scales >~10'. Recent progress in

A. A. Zdziarski, P. Magdziarz

We propose that the UV/X-ray correlation observed in NGC 4151 by EXOSAT and IUE is due to reemission of the X-ray flux absorbed by cold clouds in the line of sight. This transmission model satisfies the energy balance, provides a good fit to the X-ray and UV data, and predicts no Compton reflection of X-rays (as observed). The correlation can alternatively b

Steven B. Bradlow, Oscar Garcia-Prada

A `coherent system' $(\Cal E,V)$, consists of a holomorphic bundle plus a linear subspace of its space of holomorphic sections. Based on the usual notion in Geometric Invariant Theory, a notion of slope stability has been defined for such objects (by Le Potier, and also by Rhagavendra and Vishwanath). In this paper we show that stability in this sense is

Israel Vainsencher

We answer a question posed by S. Kleiman concerning flatness of the family of complete quadrics. We also show that any flat family of hypersurfaces on Grassmann varieties induces a flat family of intersections with the corresponding flag variety.

E. A. Kolganova, A. K. Motovilov

Algorithm, based on explicit representations for analytic continuation of the T-matrix Faddeev components on unphysical sheets, is worked out for calculations of resonances in the three-body quantum problem. According to the representations, poles of T-matrix, scattering matrix and Green function on unphysical sheets, interpreted as resonances, coincide with

A. Marshakov

The exact solutions to quantum string and gauge field theories are discussed and their formulation in the framework of integrable systems is presented. In particular I consider in detail several examples of appearence of solutions to the first-order integrable equations of hydrodynamical type and stress that all known examples can be treated as partial solut

S. Catani, M. L. Mangano, P. Nason, L. Trentadue

We reexamine the top quark production cross section at the Tevatron and LHC, in the light of recent progress on the resummation of logarithmic soft gluon corrections. We find that resummation effects are much smaller than previously thought. We also compute Coulombic threshold effects, and find them negligible. We update the discussion of uncertainties due t

Lee Samuel Finn

The LIGO Research Community (LRC) is an independent organization of researchers interested in the scientific opportunities created by the construction and operation of the Laser Interferometer Gravitational-wave Observatory (LIGO). Membership is open to all interested individuals, irrespective of any other affiliations (including affiliation with the LIGO pr

Gordon W. Semenoff, Richard J. Szabo

We consider a variation of $O(N)$-symmetric vector models in which the vector components are Grassmann numbers. We show that these theories generate the same sort of random polymer models as the $O(N)$ vector models and that they lie in the same universality class in the large-$N$ limit. We explicitly construct the double-scaling limit of the theory and show

Jes Madsen, Dan M. Jensen, Michael B. Christiansen

The rate of quark-gluon plasma droplet nucleation in superheated hadronic matter is calculated within the MIT bag model. The requirements of color singletness and (to less extent) fixed momentum suppress the nucleation rate by many orders of magnitude, making thermal nucleation of quark-gluon plasma droplets unlikely in ultrarelativistic heavy-ion collisions

Uta Fritze - von Alvensleben

I will present a review of some of the many recent developments within the exciting and rapidly evolving field of Interacting and Merging Galaxies. I will touch both on observations and on theory, focussing on those aspects where galaxy evolution modelling may possibly contribute to our understanding. After briefly outlining the basic concepts and a few spec

P. Coleman, A. J. Schofield, A. M. Tsvelik

We observe that the appearance of two transport relaxation times in the various transport coefficients of cuprate metals may be understood in terms of scattering processes that discriminate between currents that are even, or odd under the charge conjugation operator. We develop a transport equation that illustrates these ideas and discuss its experimental an

S. Zakrzewski

We show that a Poisson Lie group $(G,π)$ is coboundary if and only if the natural action of $G\times G$ on $M=G$ is a Poisson action for an appropriate Poisson structure on $M$ (the structure turns out to be the well known $π_+$). We analyze the same condition in the context of Hopf algebras. Quantum analogue of the $π_+$ structure on SU(N) is described in t

S. Majid

We show that the action of the special conformal transformations of the usual (undeformed) conformal group is the $q\to 1$ scaling limit of the braided adjoint action or $R$-commutator of $q$-Minkowski space on itself. We also describe the $q$-deformed conformal algebra in $R$-matrix form and its quasi-$*$ structure.

A. A. Tseytlin

Supersymmetric extreme dyonic black holes of toroidally compactified heterotic or type II string theory can be viewed as lower-dimensional images of solitonic strings wound around a compact dimension. We consider conformal sigma models which describe string configurations corresponding to various extreme dyonic black holes in four and five dimensions. These

Simon Davis

Elimination of the fibre coordinate dependence from the connection form transformation rule for a bundle with a coset manifold standard fibre reduces the structure group. The nonlinear SU(4) action on an $S^7$ bundle is applied to the dimensional reduction of eleven-dimensional supergravity and ten-dimensional superstring theory to four dimensions. A princip

Ron Perline

We describe a method of constructing Weingarten systems of triply orthogonal coordinates, related to the localized induction equation hierarchy of integrable geometric evolution equations

L. P. Horwitz

The fundamental axioms of the quantum theory do not explicitly identify the algebraic structure of the linear space for which orthogonal subspaces correspond to the propositions (equivalence classes of physical questions). The projective geometry of the weakly modular orthocomplemented lattice of propositions may be imbedded in a complex Hilbert space; this

S. Zakrzewski

An introduction to inhomogeneous Poisson groups is given. Poisson inhomogeneous $O(p,q)$ are shown to be coboundary, the generalized classical Yang-Baxter equation having only one-dimensional right hand side. Normal forms of the classical $r$-matrices for the Poincaré group (inhomogeneous $O(1,3)$) are calculated.

Y. Umino, J. M. Udias

Relativistic exchange current corrections to the impulse approximation in low and intermediate energy neutrino--nucleus scattering are presented assuming non--vanishing strange quark form factors for constituent nucleons. Two--body exchange current operators which treat {\em all} $SU(3)$ vector and axial currents on an equal footing are constructed by genera

Y. S. Kim

The internal space-time symmetries of relativistic particles are dictated by Wigner's little groups. The $O(3)$-like little group for a massive particle at rest and the $E(2)$-like little group of a massless particle are two different manifestations of the same covariant little group. Likewise, the quark model and parton pictures are two different manife

Edward P. Osipov

We construct the solution $ϕ(t,{\bf x})$ of the quantum wave equation $\Boxϕ+ m^2ϕ+ λ:\!\!ϕ^3\!\!: = 0$ as a bilinear form which can be expanded over Wick polynomials of the free $in$-field, and where $:\!ϕ^3(t,{\bf x})\!: $ is defined as the normal ordered product with respect to the free $in$-field. The constructed solution is correctly defined as a biline

Pietro Menotti, Pier Paolo Peirano

By adopting the standard definition of diffeomorphisms for a Regge surface we give an exact expression of the Liouville action both for the sphere and the torus topology in the discretized case. The results are obtained in a general way by choosing the unique self--adjoint extension of the Lichnerowicz operator satisfying the Riemann--Roch relation. We also

Martin O'Loughlin

In the vicinity of points in Calabi-Yau moduli space where there are degenerating three-cycles the low energy effective action of type IIA string theory will contain significant contributions arising from membrane instantons that wrap around these three-cycles. We show that the world-volume description of these instantons is Chern-Simons theory.

Stefano Ranfone, J. W. F. Valle

We present a viable flipped version of the SO(10) model consistent with the phenomenological requirements of having a non-trivial quark mixing matrix, natural doublet-triplet splitting, and a single pair of light electroweak Higgs doublet scalar bosons. In the presence of suitable non-renormalizable superpotential terms the model can reproduce the hierarchy

G. F. Giudice, M. L. Mangano, G. Ridolfi, R. Rueckl

Review of prospects for discovery of new physics signals at LEP2. The areas covered include SUSY, exotic fermions, BESS models, leptoquarks, virtual effects and CP violating observables.

Nir Polonsky

The equality assumption of the b and tau Yukawa couplings at the grand-unification scale can strongly constrain the allowed parameter space of supersymmetric models. We examine the constraints in the case that there is a discrepancy > 10% in the gauge coupling unification assumption (which necessarily implies large perturbations at the grand scale). The cons

I. M. Dremin, V. A. Nechitailo, M. Biyajima

It is shown that QCD with vector gluons predicts drastically different multiplicity distributions compared to the scalar $λφ^3$-model (in 6 dimensions). In particular, the QCD predicted minimum of cumulant moments of the distributions at ranks about $5\div7$ does not reveal itself in the scalar model. The oscillations at higher ranks survive only. Thus, the

Noriaki Kitazawa, Nobuchika Okada, Shin Sasaki

A simple model of the Majorana neutrino with the see-saw mechanism is studied, assuming that two light neutrinos are the hot dark matters with equal mass of 2.4 eV in the cold plus hot dark matter model of cosmology. We find that the heavy neutrino, which is the see-saw partner with the remaining one light neutrino, can be the cold dark matter, if the light

M. L. Mangano, G. Ridolfi, E. Accomando, S. Asai

Review of Monte Carlo event generators for signals of new particles at LEP2. The areas covered include SUSY, HIGGS and Leptoquarks.

A. V. Leonidov, D. M. Ostrovsky

The phenomenological energy dissipation in QCD jets evolution with colour coherence is considered and the corresponding modified parton multiplicity and distribution function are computed.

UKQCD Collaboration, J M Flynn, J Nieves

We report on a lattice calculation of the form factors A_0 and A_3 for the pseudoscalar to vector meson semileptonic decay Bbar^0 to rho^+ l^- nubar_l. We find that resonant (or pole-type) contributions alone are unable to describe these two form factors simultaneously. For the quantity A_0(q^2=0), which is important phenomenologically for the determination

T. Han

We discuss the Standard-Model Higgs boson production in the channels $e^-e^-\to e^-e^- H$, $e^-νW^- H$, and $e^-e^- ZH We also illustrate the enhancements in the $W^-W^-$ cross section that would result from a strongly-interacting Higgs sector or from a $H^{--}$ resonance in a doublet + triplet scalar field model.

O. A. Borisenko, V. K. Petrov, G. M. Zinovjev, J. Boháčik

An approach to studying lattice gauge models in the weak coupling region is proposed. Conceptually, it is based on the crucial role of the original Z(N) symmetry and the invariant gauge group measure. As an example, we calculate an effective model from the compact Wilson formulation of the SU(2) gauge theory in $d=3D3$ dimensions at zero temperature. Confini

S. Aid

An investigation of the hadronic final state in diffractive and non--diffractive deep--inelastic electron--proton scattering at HERA is presented, where diffractive data are selected experimentally by demanding a large gap in pseudo --rapidity around the proton remnant direction. The transverse energy flow in the hadronic final state is evaluated using a set

SLD Collaboration

We present the first experimental study of the ratio of cumulant to factorial moments of the charged-particle multiplicity distribution in high-energy particle interactions, using hadronic Z$^0$ decays collected by the SLD experiment at SLAC. We find that this ratio, as a function of the moment-rank $q$, decreases sharply to a negative minimum at $q=5$, whic

I. B. Khriplovich, A. A. Pomeransky

Spin-orbit and spin-spin effects in the gravitational interaction are treated in a close analogy with the fine and hyperfine interactions in atoms. The proper definition of the cener-of-mass coordinate is discussed. The technique developed is applied then to the gravitational radiation of compact binary stars. Our result for the spin-orbit correction differs

Jorge Pullin

Contents: Editorial, J. Pullin Report from the APS TGG, Beverly Berger We hear that..., J. Pullin LIGO project status, S. Whitcomb General relativity survives another test, C. Will Macroscopic deviations from Hawking radiation? L. Smolin Event horizons and topological censorship, E. Seidel Critical behavior in black hole collapse, J. Horne Third Texas Worksh

Dusa McDuff, Margaret Symington

In this note we apply a 4-fold sum operation to develop an associativity rule for the pairwise symplectic sum. This allows us to show that certain diffeomorphic symplectic $4$-manifolds made out of elliptic surfaces are in fact symplectically deformation equivalent. We also show that blow-up points can be traded from one side of a symplectic sum to another w

Anton Yu. Alekseev

Let $G_¶$ be a compact simple Poisson-Lie group equipped with a Poisson structure $¶$ and $(M, ø)$ be a symplectic manifold. Assume that $M$ carries a Poisson action of $G_¶$ and there is an equivariant moment map in the sense of Lu and Weinstein which acts to the dual Poisson-Lie group $G^*_¶$, $\m: M\rightarrow G^*_¶$. We prove that $M$ always possesses an

A. L. Delcher, A. J. Grove, S. Kasif, J. Pearl

Traditional databases commonly support efficient query and update procedures that operate in time which is sublinear in the size of the database. Our goal in this paper is to take a first step toward dynamic reasoning in probabilistic databases with comparable efficiency. We propose a dynamic data structure that supports efficient algorithms for updating and

G. Brewka

The paper describes an extension of well-founded semantics for logic programs with two types of negation. In this extension information about preferences between rules can be expressed in the logical language and derived dynamically. This is achieved by using a reserved predicate symbol and a naming technique. Conflicts among rules are resolved whenever poss

Jaime E. Santos, Gunter M. Schutz, Robin B. Stinchcombe

We discuss a reaction-diffusion model in one dimension subjected to an external driving force. Each lattice site may be occupied by at most one particle. The particles hop with asymmetric rates (the sum of which is one) to the right or left nearest neighbour site if it is vacant, and annihilate with rate one if it is occupied. We compute the long time behavi

B. Spivak, A. Zyuzin

We consider a mesoscopic mechanism of the exchange interaction in a system of alternating ferromagnetic/nonmagnetic metallic layers. In the case of small mesoscopic samples the sign and the amplitude of the exchange energy turn out to be random sample specific quantities. They can be changed by applying an external magnetic field, by attaching to the system

Dietmar Weinmann, Jean-Louis Pichard

We consider two particles with a local interaction $U$ in a random potential at a scale $L_1$ (the one particle localization length). A simplified description is provided by a Gaussian matrix ensemble with a preferential basis. We define the symmetry breaking parameter $μ\propto U^{-2}$ associated to the statistical invariance under change of basis. We show

S. Galluccio, R. Graber

We study the depinning phase transition of a directed polymer in a $d$-dimensional space by a periodic potential localized on a straight line. We give exact formulas in all dimensions for the critical pinning we need to localize the polymer. We show that a bounded state can still arise even if, in average, the potential layer is not attractive and for diverg

Marc Mezard, Giorgio Parisi

We propose a method to study quantitatively the glass transition in a system of interacting particles. In spite of the absence of any quenched disorder, we introduce a replicated version of the hypernetted chain equations. The solution of these equations, for hard or soft spheres, signals a transition to the glass phase. However the predicted value of the en

A. J. Roberts, A. Cronin

We present a novel method for determining multi-fractal properties from experimental data. It is based on maximising the likelihood that the given finite data set comes from a particular set of parameters in a multi-parameter family of well known multi-fractals. By comparing characteristic correlations obtained from the original data with those that occur in

R. J. Nemiroff, J. P. Norris, J. T. Bonnell, J. D. Scargle

We investigate whether a simple cosmology can fit GRB results in both time dilation and Log N - Log P simultaneously. Simplifying assumptions include: all GRBs are spectrally identical to BATSE trigger 143, $Ω=1$ universe, and no luminosity and number density evolution. Observational data used includes: the BATSE 3B peak brightness distribution (64-ms time s

Fred C. Adams, Greg Laughlin

Motivated by recent measurements which suggest that roughly half the mass of the galactic halo may be in the form of white dwarfs, we study the implications of such a halo. We first use current limits on the infrared background light and the galactic metallicity to constrain the allowed initial mass function (IMF) of the stellar population that produced the

P. Hoeflich

We present an analysis of the observed light curves and spectra of the Type Ia supernova SN1994D in the galaxy NGC 4526. The sensitivity of theoretical light curves and spectra to the underlying hydrodynamical model is discussed. The calculations are consistent with respect to the explosion mechanism, the optical and infrared light curves, and the spectral e

E. Vazquez-Semadeni, T. Passot, A. Pouquet

We discuss the role of turbulence in cloud and star formation, as observed in numerical simulations of the interstellar medium. Turbulent compression at the interfaces of colliding gas streams is responsible for the formation of intermediate ($\simlt 100$ pc) and small clouds (a few tens of pc), although the smallest clouds can also form from fragmentation o

R. Tantalo, C. Chiosi, A. Bressan, F. Fagotto

In this paper we present new chemo-spectro-photometric models of elliptical galaxies in which infall of primordial gas is allowed to occur. They aim to simulate the collapse of a galaxy made of two components, i.e. luminous material and dark matter. The mass of the dark component is assumed to be constant in time, whereas that of the luminous material is sup

Somak Raychaudhury, William C. Saslaw

We give the first determination of the observed peculiar velocity distribution function for a representative sample of galaxies (within 50 Mpc (H=100) of the Local Group), which includes a wide range of clustering properties. We explore in detail the effects of uncertainties in sampling and in distance measures on the estimated distribution function. The obs

C. B. Netterfield, M. J. Devlin, N. Jarosik, L. Page

We report on a measurement of the angular power spectrum of the anisotropy in the Cosmic Microwave Background. The anisotropy is measured in 23 different multipole bands from l=54 (~3 deg) to l=404 (~0.45 deg) and in 6 frequency bands from 26 GHz to 46 GHz over three observing seasons. The measurements are consistent from year to year. The frequency spectral

E. J. Wollack, M. J. Devlin, N. Jarosik, C. B. Netterfield

We describe an off-axis microwave telescope for observations of the anisotropy in the cosmic microwave background (CMB) radiation on angular scales between 0.5 deg and 3 deg. The receiver utilizes cryogenic high-electron-mobility transistor (HEMT) amplifiers and detects the total power in multiple 3 GHz wide channels. Both frequency and polarization informat

J. Ballesteros-Paredes, E. Vazquez-Semadeni

We present preliminary results on the energy budgets of clouds in two-dimensional numerical simulations of the interstellar medium. Using an automated cloud-identification algorithm, we calculate the gravitational, internal, kinetic and magnetic energies of the clouds. We find that, within a dispersion of roughly one order of magnitude, the gravitational ene