Material screening and selection for XENON100

Results of the extensive radioactivity screening campaign to identify materials for the construction of XENON100 are reported. This Dark Matter search experiment is operated underground at Laboratori Nazionali del Gran Sasso (LNGS), Italy. Several ultra sensitive High Purity Germanium detectors (HPGe) have been used for gamma ray spectrometry. Mass spectrometry has been applied for a few low mass plastic samples. Detailed tables with the radioactive contaminations of all screened samples are presented, together with the implications for XENON100.Comment: 8 pages, 1 figur

The XENON100 Dark Matter Experiment

The XENON100 dark matter experiment uses liquid xenon (LXe) in a time projection chamber (TPC) to search for Xe nuclear recoils resulting from the scattering of dark matter Weakly Interacting Massive Particles (WIMPs). In this paper we present a detailed description of the detector design and present performance results, as established during the commissioning phase and during the first science runs. The active target of XENON100 contains 62 kg of LXe, surrounded by an LXe veto of 99 kg, both instrumented with photomultiplier tubes (PMTs) operating inside the liquid or in Xe gas. The LXe target and veto are contained in a low-radioactivity stainless steel vessel, embedded in a passive radiation shield. The experiment is installed underground at the Laboratori Nazionali del Gran Sasso (LNGS), Italy and has recently published results from a 100 live-days dark matter search. The ultimate design goal of XENON100 is to achieve a spin-independent WIMP-nucleon scattering cross section sensitivity of \sigma = 2x10^-45 cm^2 for a 100 GeV/c^2 WIMP.Comment: 23 pages, 27 figures; version accepted by journa

The structure of PGC Morale Scale in American and Japanese aged: A further note

This study involves a further replication of cross-cultural comparison of the structure of the Philadelphia Geriatric Center Morale Scale (PGCMS). Using Japanese and American data sets, the present research replicates and extends the findings reported by Liang et al. (1987). In particular, the earlier findings that four PGCMS items behave differently in two cultures are replicated. The present study yields two additional observations. First, the invariance in the PGCMS can now be extended beyond the urban elderly residents studied by Liang et al. (1987) to the entire aged population in the U.S. and Japan. Second, this comparability is robust despite the elimination of correlated measurement errors from the earlier specifications and when several exogenous variables are controlled. Further, the impact of selected demographic variables on the PGCMS was evaluated. In addition, qualitative data from in-depth interviews provide further insights concerning the cultural differences in the expression of well-being.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42991/1/10823_2004_Article_BF00116576.pd

Cervical screening: the optimum visit plan for contacting users and non-users in Scotland.

OBJECTIVE--To investigate the numbers of visits required to obtain interviews with users and non-users of cervical screening, and to determine the workload involved to enable an optimum visit plan to be developed. DESIGN--Case-control study of users and non-users of cervical screening using a flexible visit plan that involved up to eight attempts at contact. Visits were made in mornings, afternoons, and evenings, the visit pattern being determined by information gained from local sources. PATIENTS--Altogether 660 non-users of cervical screening (cases), aged 20-64 and registered with 23 randomly selected general practitioners (GPs), were identified from the Tayside computerised register of cervical smears. These women were selected from the computerised lists of 18 GPs in Dundee and five in Perth. A total of 417 women recorded as having a smear within the previous three years (controls), matched by age and GP, were also identified from the computerised register. RESULTS--Altogether 1834 attempts were made to contact the cases, of whom 339 were interviewed, giving a workload of 18 interviews per 100 attempts. For the controls 1359 attempts were made at contact to yield 339 interviews, a workload of 25 interviews per 100 attempts. Refusals (19%) and incorrect addresses (23%) were the two major reasons for failing to achieve interview. Only for four (0.6%) of the cases and one (0.2%) of the controls was no information gained. The proportion of attempts which led to interview remained constant with increasing numbers of call-backs (up to six for the cases and eight for the controls). CONCLUSIONS--A flexible approach to visit scheduling that takes account of local knowledge can lead to interviews with 66% of non-users of health screening, when incorrect addresses are removed. It is preferable to plan for many (up to six) visits to achieve interview. This will minimise non-response bias without increasing the workload per successful interview

Brainchild 2015

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