COMPASS is a new fixed target experiment at CERN to study the nucleon spin structure with a polarized muon beam and a polarized nucleon target. Gluon spin contribution to the nucleon spin will be studied by measuring the asymmetry of open charm production or high PT hadron pair production in semi-inclusive deep inelastic scattering of a polarized muons on a polarized nucleon target. The COMPASS...

COMPASS is a fixed target experiment at CERN studying the spin structure of the nucleon via deep inelastic muon-nucleon scattering. Hadron spectroscopy and structure are investigated using hadronic beams. The main goal of the muon program is the determination of the gluon helicity contribution, ∆G/G, to the nucleon spin. Experimentally this quantity is accessible via the measurement of double s...

Background: Aim of this study is to evaluate the accuracy of the gated volumetric modulated arc therapy (VMAT/RapidArc) using 2D planar dosimetry, DynaLog files and COMPASS 3D dosimetry system. Materials and Methods: Pre-treatment quality assurance of 10 gated VMAT plans was verified using 2D array and COMPASS 3D dosimetry system. Advantage of COMPASS over 2D planar is that it provides the clin...

background: aim of this study is to evaluate the accuracy of the gated volumetric modulated arc therapy (vmat/rapidarc) using 2d planar dosimetry, dynalog files and compass 3d dosimetry system. materials and methods: pre-treatment quality assurance of 10 gated vmat plans was verified using 2d array and compass 3d dosimetry system. advantage of compass over 2d planar is that it provides the clin...

COMPASS measurements of the gluon polarisation in nucleon, ∆G/G, are reviewed. Two different approaches based on tagging the Photon Gluon Fusion process are described. They rely on the open charm meson or high–pT hadron pairs detection. The obtained results are: −0.57 ± 0.41 (stat.) ± 0.17 (syst.) for the open charm, 0.06 ± 0.31 (stat.) ± 0.06 (syst.) and 0.016 ± 0.058 (stat.) ± 0.055 (syst.) f...

The impact of the recent very precise CLAS and COMPASS g1/F1 data on polarized parton densities and higher twist effects is discussed. We demonstrate that the low Q CLAS data improve essentially our knowledge of higher twist corrections to the spin structure function g1, while the large Q 2 COMPASS data influence mainly the strange quark and gluon polarizations which slightly decrease. We find ...

In March 2012, CCRC released two studies examining how well two widely used assessment tests—COMPASS and ACCUPLACER—predict the subsequent performance of entering students in their college-level courses. The studies, Do High-Stakes Placement Exams Predict College Success? and Predicting Success in College: The Importance of Placement Tests and High School Transcripts, can be found at http://ccr...

Honeybees have at least three compass mechanisms: a magnetic compass; a celestial or sun compass, based on the daily rotation of the sun and sun-linked skylight patterns; and a backup celestial compass based on a memory of the sun's movements over time in relation to the landscape. The interactions of these compass systems have yet to be fully elucidated, but the celestial compass is primary in...

W propose an adaptive hyperbox algorithm (AHA), which is an instance of a locally convergent, random search algorithm for solving discrete optimization via simulation problems. Compared to the COMPASS algorithm, AHA is more efficient in high-dimensional problems. By analyzing models of the behavior of COMPASS and AHA, we show why COMPASS slows down significantly as dimension increases, whereas ...