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Guide to the Main Ring DO overpass
The DO overpass is a modification of the beam orbit in Main Ring in order to better accommodate a Tevatron collider detector at DO. The orbit is moved up approx. 51 inches over most of the long straight section at DO, thus making the Main Ring the world's first non-planar proton synchrotron. A similar overpass, but with four times the displacement, is planned for the CDF detector at the BO straight section. The nominal separation between the beam orbit in the Main Ring and the orbit in the Tevatron is 25.5 inches. Early in the design study of a detector that would utilize the Tevatron is a anti pp collider, it was apparent that a larger separation at the detector was highly desirable. In 1981, Tom Collins proposed a specific lattice geometry in the Main Ring for achieving larger separation, called ''the screw beam''. His proposal has served as the basis for the design of both the BO and DO overpasses. The main purpose of this report is to describe in some detail the implementation of the DO overpass. Topics to be covered include: (a) geometry of the overpass orbit, (b) the new hardware in the tunnel, (c) the power supply system, (d) the control facility, (e) accelerator beam dynamics ramifications, and (f) commissioning experience. A secondary purpose is to provide a fairly complete ''bibliography'' to the sources of information on the overpass. 17 refs., 17 figs
External audit of providers of the Cervical Cancer Prevention Programme in Poland in 2016/2017
Introduction. The Cervical Cancer (CC) Prevention Programme includes 3 phases: basic (Pap smear collection), diagnostic (Pap smear evaluation) and in-depth (colposcopy/biopsy in case of abnormal smear test findings). The Programme service providers are subject to an external audit and this publication’s objective is to analyse its results from 2016 and the first half of 2017. Materials and methods. The audit of the Programme performance in the period 01.01.2016–30.06.2017 was carried out by external auditors by way of personal visits to the offices of the service providers and by way of direct data retrieval. The audit covered 12% (198) of the basic phase, 100% (66) of the diagnostic phase and 100% (62) of the in-depth phase facilities. The Polish National Health Fund (NHF) did not make available the routinely collected data for the purpose of audit. Audit data collected in the developed protocols were analysed. Results. The number of Pap smears (2,028,988) and the number of colposcopies (13,636) outside the Programme was, respectively, more than two and three times higher than in the Programme (cytology — 801,640, colposcopy — 3929). The performance of the procedures (Programme vs outside the Programme) was highly variable depending on the provider. The percentage of Pap smears unsuitable for evaluation did not differ significantly between gynaecologists and midwives. All audited cytological laboratories carried out rescreening of samples. Biopsy was not performed in 11% (2016) and 15% (2017) of colposcopy laboratories. Inaccuracies were found in 19% (61) of the audit protocols. Discussion. Significantly higher number of procedures performed outside the Programme results from lower renumeration of procedures within the Programme. Variable provider's preferences in the mode of procedures execution indicates that with the use of appropriate organisational solutions it would be possible to reduce opportunistic screening, which is of unknown quality. The quality of Pap smear sample collection in the case of gynaecologists and midwives is the same, but the number of primary care provider (PCP) facilities where midwives collect smears is very limited. The inaccuracies noted in the audit protocols indicate that the lack of access to data collected by the National Health Fund decreased the quality of the audit carried out and the reliability of the data obtained. Conclusions. Restoring full access to data collected by the NHF is crucial for the Programme audit quality. Measures should be implemented to reduce opportunistic screening and shift the stream of tests to the Programme (both at the basic and at the in-depth phase), and to increase the availability of tests in PCP facilities through training for midwives.
Evidence for hadronic deconfinement in -p collisions at 1.8 TeV
We have measured deconfined hadronic volumes, fm,
produced by a one dimensional (1D) expansion. These volumes are directly
proportional to the charged particle pseudorapidity densities . The hadronization temperature is (syst)
MeV. Using Bjorken's 1D model,the hadronization energy density is (stat) GeV/fm corresponding to an excitation of (stat) quark-gluon degrees of freedom.Comment: 15 pages, 3 figures, 2 table
QCD and models on multiplicities in and interactions
A brief survey of theoretical approaches to description of multiplicity
distributions in high energy processes is given. It is argued that the
multicomponent nature of these processes leads to some peculiar characteristics
observed experimentally. Predictions for LHC energies are presented. It is
shown that similarity of the energy dependence of average multiplicities in
different reactions is not enough alone to suggest the universal mechanism of
particle production in strongly-interacting systems. Other characteristics of
multiplicity distributions depend on the nature of colliding partners.Comment: 16 pages, 11 figures, Phys. Atom. Nuc
Measurement of the cross-section ratio sigma_{psi(2S)}/sigma_{J/psi(1S)} in deep inelastic exclusive ep scattering at HERA
The exclusive deep inelastic electroproduction of and
at an centre-of-mass energy of 317 GeV has been studied with the ZEUS
detector at HERA in the kinematic range GeV,
GeV and GeV, where is the photon virtuality, is the
photon-proton centre-of-mass energy and is the squared four-momentum
transfer at the proton vertex. The data for GeV were taken in
the HERA I running period and correspond to an integrated luminosity of 114
pb. The data for GeV are from both HERA I and HERA II
periods and correspond to an integrated luminosity of 468 pb. The decay
modes analysed were and for the
and for the . The cross-section ratio
has been measured as a function of
and . The results are compared to predictions of QCD-inspired
models of exclusive vector-meson production.Comment: 24 pages, 8 figure
Combined QCD and electroweak analysis of HERA data
A simultaneous fit of parton distribution functions (PDFs) and electroweak
parameters to HERA data on deep inelastic scattering is presented. The input
data are the neutral current and charged current inclusive cross sections which
were previously used in the QCD analysis leading to the HERAPDF2.0 PDFs. In
addition, the polarisation of the electron beam was taken into account for the
ZEUS data recorded between 2004 and 2007. Results on the vector and
axial-vector couplings of the Z boson to u- and d-type quarks, on the value of
the electroweak mixing angle and the mass of the W boson are presented. The
values obtained for the electroweak parameters are in agreement with Standard
Model predictions.Comment: 32 pages, 10 figures, accepted by Phys. Rev. D. Small corrections
from proofing process and small change to Fig. 12 and Table
Limits on the effective quark radius from inclusive scattering at HERA
The high-precision HERA data allows searches up to TeV scales for Beyond the
Standard Model contributions to electron-quark scattering. Combined
measurements of the inclusive deep inelastic cross sections in neutral and
charged current scattering corresponding to a luminosity of around 1
fb have been used in this analysis. A new approach to the beyond the
Standard Model analysis of the inclusive data is presented; simultaneous
fits of parton distribution functions together with contributions of "new
physics" processes were performed. Results are presented considering a finite
radius of quarks within the quark form-factor model. The resulting 95% C.L.
upper limit on the effective quark radius is cm.Comment: 10 pages, 4 figures, accepted by Phys. Lett.
Search for a narrow baryonic state decaying to and in deep inelastic scattering at HERA
A search for a narrow baryonic state in the and
system has been performed in collisions at HERA with the ZEUS detector
using an integrated luminosity of 358 pb taken in 2003-2007. The search
was performed with deep inelastic scattering events at an centre-of-mass
energy of 318 GeV for exchanged photon virtuality, , between 20 and 100
. Contrary to evidence presented for such a state around 1.52
GeV in a previous ZEUS analysis using a sample of 121 pb taken in
1996-2000, no resonance peak was found in the invariant-mass
distribution in the range 1.45-1.7 GeV. Upper limits on the production cross
section are set.Comment: 16 pages, 4 figures, accepted by Phys. Lett. B. Minor changes from
journal reviewing process, including a small correction to figure
Measurement of neutral current e+/-p cross sections at high Bjorken x with the ZEUS detector
The neutral current e+/-p cross section has been measured up to values of
Bjorken x of approximately 1 with the ZEUS detector at HERA using an integrated
luminosity of 187 inv. pb of e-p and 142 inv. pb of e+p collisions at sqrt(s) =
318GeV. Differential cross sections in x and Q2, the exchanged boson
virtuality, are presented for Q2 geq 725GeV2. An improved reconstruction method
and greatly increased amount of data allows a finer binning in the high-x
region of the neutral current cross section and leads to a measurement with
much improved precision compared to a similar earlier analysis. The
measurements are compared to Standard Model expectations based on a variety of
recent parton distribution functions.Comment: 39 pages, 9 figure
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