195 research outputs found

    Ariel - Volume 5 Number 4

    Get PDF
    Editors Mark Dembert J.D. Kanofskv Entertainment Editors Robert Breckenridge Joe Conti Overseas Editor Mike Sinason Photographer Scott Kastner Epistemologist Gary Kaskey Staff Ken Jaffe Bob Sklaroff Janet Weish David Jacoby Phil Nimoityn Circulation Editor Jay Amsterdam Humorist Jim Mccan

    Ariel - Volume 6 Number 3

    Get PDF
    Editors Mark Dembert J.D. Kanofsky Frank Chervenak John Lammie Curt Cummings Staff Ken Jaffe Bob Sklaroff Halley Faust Jim Burke Nancy Redfern Hans Weltin Photographer Larry Glazerman Overseas Editor Mike Sinason Humorist Jim McCan

    Large stellar disks in small elliptical galaxies

    Get PDF
    We present the rotation velocities V and velocity dispersions sigma along the principal axes of seven elliptical galaxies less luminous than M_B= -19.5. These kinematics extend beyond the half-light radii for all systems in this photometrically selected sample. At large radii the kinematics not only confirm that rotation and "diskiness" are important in faint ellipticals, as was previously known, but also demonstrate that in most sample galaxies the stars at large galactocentric distances have (V/sigma)_max of about 2, similar to the disks in bona-fide S0 galaxies. Comparing this high degree of ordered stellar motion in all sample galaxies with numerical simulations of dissipationless mergers argues against mergers with mass ratios <=3:1 as an important mechanism in the final shaping of low-luminosity ellipticals, and favors instead the dissipative formation of a disk.Comment: 11 pages LaTex with 4 Postscript figure

    More on the Burkhardt-Cottingham Sum Rule in QCD

    Full text link
    The QCD higher order effects to the polarized structure function g2(x,Q2)g_2(x, Q^2 ) are reanalyzed for massive quarks in the context of the operator product expansion. We confirm that the lowest moment of g2(x,Q2)g_2 (x, Q^2 ) which corresponds to the Burkhardt-Cottingham sum rule does {\sl not} suffer from radiative corrections in perturbative QCD.Comment: LaTeX, 9 pages, 1 figure appended after \end{document} as an uu-encoded and compressed .ps file, KUCP-70;HUPD-9410;YNU-HEPTh-94-10

    Ariel - Volume 6 Number 4

    Get PDF
    Editors Mark Dembert J.D. Kanofsky Frank Chervenak John Lammie Curt Cummings Entertainment Robert Breckenridge Joe Conti Gary Kaskey Photographer Larry Glazerman Overseas Editor Mike Sinason Humorist Jim McCann Staff Ken Jaffe Bob Sklaroff Halley Faust Jim Burk

    Ariel - Volume 6 Number 4 (Alternate Version)

    Get PDF
    Editors Mark Dembert J.D. Kanofsky Frank Chervenak John Lammie Curt Cummings Entertainment Robert Breckenridge Joe Conti Gary Kaskey Photographer Larry Glazerman Overseas Editor Mike Sinason Humorist Jim McCann Staff Kenn Jaffe Bob Sklaroff Halley Faust Jim Burke Jay Amsterdam Morton A. Klein Nancy Redfer

    Vegetation history and climatic fluctuations on a transect along the Dead Sea west shore and impact on past societies over the last 3500 years.

    Get PDF
    This study represents the vegetation history of the last 3500 years and conducts an analysis of the climatic fluctuations on a 75 km long transect on the western Dead Sea shore. Palynological and sedimentological data are available from six cores near Mount Sedom, Ein Boqueq, and Ein Gedi and from outcrops near Ze'elim and Ein Feshkha. The comparison of the pollen data with the lake levels shows synchronous trends. During the Middle Bronze Age, Iron Age and Hellenistic to Byzantine Period the high lake level of the Dead Sea signals an increase in precipitation. Contemporaneously, values of cultivated plants indicate an increase in agriculture. Lake level is low during the Late Bronze Age, within the Iron Age and at the end of the Byzantine period, indicating dry periods when all pds show a decrease of cultivated plants. Forest regeneration led by drought-resistant pines is observed in all pollen diagrams (pds) following the agricultural decline in the Byzantine period and, in the pds near Ein Boqeq, Ze'elim and Ein Feshkha, during the late Iron Age. The modern vegetation gradient is reflected in the palaeo-records: a stronger expansion of Mediterranean vegetation and cultivated plants in the northern sites is recognisable

    Target Mass Effects in Polarized Virtual Photon Structure Functions

    Full text link
    We study target mass effects in the polarized virtual photon structure functions g1γ(x,Q2,P2)g_1^\gamma (x,Q^2,P^2), g2γ(x,Q2,P2)g_2^\gamma (x,Q^2,P^2) in the kinematic region Λ2P2Q2\Lambda^2\ll P^2 \ll Q^2, where Q2(P2)-Q^2 (-P^2) is the mass squared of the probe (target) photon. We obtain the expressions for g1γ(x,Q2,P2)g_1^\gamma (x,Q^2,P^2) and g2γ(x,Q2,P2)g_2^\gamma (x,Q^2,P^2) in closed form by inverting the Nachtmann moments for the twist-2 and twist-3 operators. Numerical analysis shows that target mass effects appear at large xx and become sizable near xmax(=1/(1+P2Q2))x_{\rm max}(=1/(1+\frac{P^2}{Q^2})), the maximal value of xx, as the ratio P2/Q2P^2/Q^2 increases. Target mass effects for the sum rules of g1γg_1^\gamma and g2γg_2^\gamma are also discussed.Comment: 24 pages, LaTeX, 9 eps figure

    Polarized Virtual Photon Structure Function g2γg_2^\gamma and Twist-3 Effects in QCD

    Full text link
    We investigate the twist-3 effects in the polarized virtual photon structure. The structure functions g1γg_1^\gamma and g2γg_2^\gamma of polarized photon could be experimentally studied in the future polarized epep or e+ee^+e^- colliders. The leading contributions to g1γg_1^\gamma are the twist-2 effects, while another structure function g2γg_2^\gamma, which only exists for the virtual photon target, receives not only the twist-2 but also twist-3 contributions. We first show that the twist-3 effects actually exist in the box-diagram contributions and we extract the twist-3 part, which can also be reproduced by the pure QED operator product expansion. We then calculate the non-trivial lowest moment (n=3n=3) of the twist-3 contribution to g2γg_2^\gamma in QCD. For large NcN_c (the number of colors), the QCD analysis of the twist-3 effects in the flavor nonsinglet part of g2γg_2^\gamma becomes tractable and we can obtain its moments in a compact form for all nn.Comment: 27 pages, LaTeX, 9 eps figures, eqsection.sty file included, Appendix A added, some minor changes for Fig.

    Spin Structure Function g_2(x,Q^2) and Twist-3 Operators in large-N_C QCD

    Get PDF
    It is shown in the framework of the operator product expansion and the renormalization group method that the twist-3 part of flavour nonsinglet spin structure function g_2(x,Q^2) obeys a simple Dokshitzer-Gribov- Lipatov-Altarelli-Parisi (DGLAP) equation in the large N_C limit even in the case of massive quarks (N_C is the number of colours). There are four different types of twist-3 operators which contribute to g_2, including quark-mass-dependent operators and the ones proportional to the equation of motion. They are not all independent but are constrained by one relation. A new choice of the independent operator bases leads to a simple form of the evolution equation for g_2 at large N_C.Comment: Corrected Ref.[15
    corecore