Vacuum polarization calculations for hydrogenlike and alkalilike ions

Complete vacuum polarization calculations incorporating finite nuclear size are presented for hydrogenic ions with principal quantum numbers n=1-5. Lithiumlike, sodiumlike, and copperlike ions are also treated starting with Kohn-Sham potentials, and including first-order screening corrections. In both cases dominant Uehling terms are calculated with high accuracy, and smaller Wichmann- Kroll terms are obtained using numerical electron Green's functions.Comment: 23 pages, 1 figur

Recoil correction to the ground state energy of hydrogenlike atoms

The recoil correction to the ground state energy of hydrogenlike atoms is calculated to all orders in \alpha Z in the range Z = 1-110. The nuclear size corrections to the recoil effect are partially taken into account. In the case of hydrogen, the relativistic recoil correction beyond the Salpeter contribution and the nonrelativistic nuclear size correction to the recoil effect, amounts to -7.2(2) kHz. The total recoil correction to the ground state energy in hydrogenlike uranium (^{238}U^{91+}) constitutes 0.46 eV.Comment: 16 pages, 1 figure (eps), Latex, submitted to Phys.Rev.

Factors Associated with Recurrence of Varicose Veins after Thermal Ablation: Results of The Recurrent Veins after Thermal Ablation Study

Background. The goal of this retrospective cohort study (REVATA) was to determine the site, source, and contributory factors of varicose vein recurrence after radiofrequency (RF) and laser ablation. Methods. Seven centers enrolled patients into the study over a 1-year period. All patients underwent previous thermal ablation of the great saphenous vein (GSV), small saphenous vein (SSV), or anterior accessory great saphenous vein (AAGSV). From a specific designed study tool, the etiology of recurrence was identified. Results. 2,380 patients were evaluated during this time frame. A total of 164 patients had varicose vein recurrence at a median of 3 years. GSV ablation was the initial treatment in 159 patients (RF: 33, laser: 126, 52 of these patients had either SSV or AAGSV ablation concurrently). Total or partial GSV recanalization occurred in 47 patients. New AAGSV reflux occurred in 40 patients, and new SSV reflux occurred in 24 patients. Perforator pathology was present in 64% of patients. Conclusion. Recurrence of varicose veins occurred at a median of 3 years after procedure. The four most important factors associated with recurrent veins included perforating veins, recanalized GSV, new AAGSV reflux, and new SSV reflux in decreasing frequency. Patients who underwent RF treatment had a statistically higher rate of recanalization than those treated with laser

Recoil correction to the bound-electron g factor in H-like atoms to all orders in αZ\alpha Z

The nuclear recoil correction to the bound-electron g factor in H-like atoms is calculated to first order in $m/M$ and to all orders in $\alpha Z$. The calculation is performed in the range Z=1-100. A large contribution of terms of order $(\alpha Z)^5$ and higher is found. Even for hydrogen, the higher-order correction exceeds the $(\alpha Z)^4$ term, while for uranium it is above the leading $(\alpha Z)^2$ correction.Comment: 6 pages, 3 tables, 1 figur

Measurement of inclusive quasielastic scattering of polarized electrons from polarized ³He

We report a measurement of the asymmetry in spin-dependent quasielastic scattering of longitudinally polarized electrons from a polarized 3He gas target. This measurement represents the first demonstration of a new method for studying electromagnetic nuclear structure: the scattering of polarized electrons from a polarized nuclear target. The measured asymmetry is in good agreement with a Faddeev calculation and supports the picture of spin-dependent quasielastic scattering from polarized 3He as predominantly scattering from a polarized neutron

Determination of the neutron electric form factor in quasielastic scattering of polarized electrons from polarized ³He

We report a measurement of the asymmetry in spin-dependent quasielastic scattering of longitudinally polarized electrons from a polarized ³He gas target. The asymmetry is measured at kinematics sensitive to the transverse-longitudinal response function RTL(Q2,ω). The value of the neutron electric form factor GEn(Q2=0.16 (GeV/c2))=+0.070±0.100±0.035 is extracted from the asymmetry using a Faddeev calculation of the ³He wave function

He→3(e→e′) quasielastic asymmetry

Measurements of the spin-dependent asymmetry in scattering longitudinally polarized electrons from polarized He3 at quasielastic kinematics are reported. The measurements were made at two kinematics and spin angles, one sensitive to the helicity-dependent transverse-longitudinal interference response function, RTL′, and the other to the helicity-dependent transverse response function, RT′. For the experiment a metastability exchange optically pumped polarized He3 target was used; a general discussion of the technique used to polarized the He3, along with the details of the design and operation of the target system, are presented here. A comparison is made of the world’s data on the He→3(e→,e′) quasielastic asymmetry with several theoretical predictions, including calculations that use the plane wave impulse approximation and a fully spin-dependent spectral function. There is good agreement between data and theory at the current level of experimental precision

Von „grünen Investitionen“ und „glühenden Landschaften“: Was sind die Treiber des Heizenergieverbrauchs in Mehrfamilienhäusern? – Ergebnisse auf Grundlage des ista-IWH-Energieeffizienzindex

Investitionen in die Energieeffizienz von Mehrfamilienhäusern müssen sich langfristig für ihre Eigentümer lohnen. Dies ist die notwendige Voraussetzung für höhere Neubau- und Sanierungsaufwendungen, die gewünscht sind, um die von der Europäischen Union und der Bundesregierung aufgerufenen Klimaziele zu erreichen. Der vorliegende Beitrag untersucht die Determinanten der Kapitalintensität im Wohnungsbau, als Näherungsgröße für die hergestellte (energetische) Qualität, und daran anschließend die Frage, wie sich diese auf den durchschnittlichen regionalen Energieverbrauch auswirkt. Die Analyse bezieht sich dabei bewusst auf Mehrfamilienhäuser, Immobilien, die nicht nur den Charakter eines Konsumguts besitzen, sondern darüber hinaus weitgehend als Renditeobjekte unterhalten werden. Dies hat Implikationen für „grüne Investitionen“ zur Verbesserung der Energieeffizienz: Geringere Energiekosten kommen nicht unmittelbar dem Investor zugute – sein Gewinn liegt vielmehr in der Veränderung der erwarteten Kaltmiete, die – neben regionalen Unterschieden in ihrer absoluten Höhe – auch unterschiedlich stark mit Risiko behaftet sein kann. Untersucht wurden diese Zusammenhänge im Rahmen der Energieeffizienzdebatte bisher jedoch noch nicht. Tatsächlich zeigt die durchgeführte empirische Untersuchung, dass Investoren Standorte mit geringerem erwartetem Risiko sowie größeren Mieterträgen bevorzugen und dort entsprechend höhere Mittel für den Geschosswohnungsbau aufwenden