82 research outputs found
The Karlsruhe temperature time series since 1779
This paper presents the long-term Karlsruhe temperature series re-digitized and reconstructed from handwritten manuscripts from 1779 to 1875 archived in various libraries. Despite great efforts, data from some periods remained missing in the manuscript departments so that the main Karlsruhe series remained partially fragmented. Combined with historic climate records available in the archive of German Weather Service (DWD), the entire series until 2008, when the official Karlsruhe station was relocated to Rheinstetten, is one of the longest climate series available for Germany. The series includes various observational parameters on a daily or even sub-daily basis converted into SI units or contemporary units. The focus of this paper is on the temperature series and presents some first statistical analyses to demonstrate the additional benefit of possessing unique long-term instrumental climate data on a sub-daily basis. The entire temperature series was homogenized with respect to consistent observation times and to an urban boundary site. It is shown that the width of the distribution function quantified from constructed daily maximum and minimum temperature has substantially broadened in the summer months, but not during winter or the entire year. The number of summer and hot days has substantially increased in the last 30–50 years, while the number of frost and ice days has decreased. Summer or hot days as well as heat waves were very rare before 1920, being unrepresentative of a period mainly unaffected by climate change. Singularities of the climate system, such as the (cold) Schafskälte in June or the (warm) Hundstage in July/August, are clearly shown in most periods. The (cold) Ice Saints in May, however, have a high frequency only in the coldest period between 1870 and 1960; they are hardly detectable in most of the preceding years. Temperature statistics show that the severity of late spring frosts has gradually increased during the entire record mainly as a result of later frost occurrences
Charmonium spectroscopy and mixing with light quark and open charm states from nF=2 lattice QCD
We study the charmonium spectrum including higher spin and gluonic
excitations. We determine an upper limit on the mixing of the eta_c ground
state with light pseudoscalar flavour-singlet mesons and investigate the mixing
of charmonia near open charm thresholds with pairs of (excited) D and anti-D
mesons. For charm and light valence quarks and nF=2 sea quarks, we employ the
non-perturbatively improved Sheikholeslami-Wohlert (clover) action. Excited
states are accessed using the variational technique, starting from a basis of
suitably optimised operators. For some aspects of this study, the use of
improved stochastic all-to-all propagators was essential.Comment: 23 pages, v2: references updated, correction of an ambiguous
statement, minor typos corrected, some figures update
Unscheduled DNA synthesis after partial UV irradiation of the cell nucleus
Cells of an euploid strain of the Chinese hamster synchronized in the G1 phase were microirradiated in the nucleus with a laser UV microbeam (λ = 257 nm) and pulse-labelled with [3H]thymidine. In autoradiographs of cells fixed immediately after the pulse unscheduled DNA synthesis (UDS) was found restricted to the microirradiated part of the nucleus. The rate of UDS varied with the UV energy applied and the post-irradiation incubation time. In other experiments chromosome preparations were established after an additional chase and a subsequent growth period. In 28 mitotic cells autoradiographic label was found concentrated on a few chromosomes which lay adjacent to each other in one part of the metaphase plate. The distribution of label on the chromosomes could clearly be distinguished from patterns which originate from semi-conservative DNA synthesis within S phase. The label on chromosomes of microirradiated cells thus represents UDS. Our findings support the following ideas on the arrangement of interphase chromosomes: (1) Decondensed interphase chromosomes may occupy rather compact territories. (2) Chromosomes do not necessarily exhibit a close and permanent association with their respective homologues
Excitations of single-beauty hadrons
In this work we study the predominantly orbital and radial excitations of
hadrons containing a single heavy quark. We present meson and baryon mass
splittings and ratios of meson decay constants (e.g., and
) resulting from quenched and dynamical two-flavor
configurations. Light quarks are simulated using the chirally improved (CI)
lattice Dirac operator at valence masses as light as MeV.
The heavy quark is approximated by a static propagator, appropriate for the
quark on our lattices ( GeV). We also include some preliminary
calculations of the kinetic corrections to the states, showing,
in the process, a viable way of applying the variational method to three-point
functions involving excited states. We compare our results with recent
experimental findings.Comment: 23 pages, 18 figures, 17 tables; slight title change (Ed. killjoy);
reference added; version to appear in Phys Rev
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