Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

X-ray emission from the Sombrero galaxy: discrete sources

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

Replication and validation of higher order models demonstrated that a summary score for the EORTC QLQ-C30 is robust.

Objective: To further evaluate the higher-order measurement structure of the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30) questionnaire, with the aim of generating a summary score. Study design and setting: Using pretreatment QLQ-C30 data (N=3,282), we conducted confirmatory factor analyses to test seven previously evaluated higher-order models. We compared the summary score(s) derived from the best performing higher-order model with the original QLQ-C30 scale scores, using tumor stage, performance status and change over time (N=244) as grouping variables. Results: Whereas all models showed acceptable fit, we continued in the interest of parsimony with known-groups validity and responsiveness analyses using a summary score derived from the single higher-order factor model. The validity and responsiveness of this QLQ-C30 Summary Score was equal to, and in many cases superior to the original, underlying QLQ-C30 scale scores. Conclusion: Our results provide empirical support for a measurement model for the QLQ-C30 yielding a single summary score. The availability of this Summary Score can avoid problems with potential Type I errors that arise due to multiple testing when making comparisons based on the 15 outcomes generated by this questionnaire, and may reduce sample size requirements for HRQL studies using the QLQ-C30 questionnaire when an overall summary score is a relevant primary outcome

Absence of progesterone receptor associated with secondary breast cancer in postmenopausal women

The relationship between expression of receptors for oestrogen and progesterone (ER and PR) and disease progression in breast cancer was investigated by comparing immunocytochemical determinations of ER and PR in fine needle aspirates from primary and secondary breast tumours. Rates of receptor expression were significantly higher in primary than in secondary lesions: for ER 63.3% (n = 689) compared with 45.3% (n = 223), and for PR 53.7% (n = 443) compared with 33.1% (n = 121). The effect of menopausal status was examined by subdividing the patient cohort into those over or under the age of 50 years. In both instances, ER expression in secondary tumours was relatively low; however, only postmenopausal patients had significantly lower rates of PR expression in secondary tumours. Consistent with this, an increase in the ER+PR– profile in secondary tumours compared with primary cases from postmenopausal patients was seen, and in a multivariate analysis, a specific absence of PR expression in secondary tumours was revealed. Comparison of ER and PR expression in simultaneously sampled primary tumours and lymph node metastases from the same patient showed that receptor expression was stable with progression to a metastatic site as results were concordant for ER in 92% (n = 88) and PR in 93.8% of cases (n = 65). These results suggest that absence of PR expression in primary breast cancer is associated with disease progression and may be a marker of an aggressive tumour phenotype. © 1999 Cancer Research Campaig

Observation of Charge-Dependent Azimuthal Correlations in p-Pb Collisions and Its Implication for the Search for the Chiral Magnetic Effect

Peer reviewe

Pseudorapidity distributions of charged hadrons in proton-lead collisions at root s(NN)=5:02 and 8.16 TeV

The pseudorapidity distributions of charged hadrons in proton-lead collisions at nucleon-nucleon center-of-mass energies root s(NN) = 5.02 and 8.16 TeV are presented. The measurements are based on data samples collected by the CMS experiment at the LHC. The number of primary charged hadrons produced in non-single-diffractive proton-lead collisions is determined in the pseudorapidity range vertical bar eta(lab)vertical bar vertical bar(vertical bar eta cm vertical bar) <0.5 are 17.1 +/- 0.01 (stat) +/- 0.59 (syst) and 20.10 +/- 0.01 (stat) +/- 0.5(syst) at root s(NN) = 5.02 and 8.16 TeV, respectively. The particle densities per participant nucleon are compared to similar measurements in proton-proton, proton-nucleus, and nucleus-nucleus collisions.Peer reviewe

Measurement of the WZ production cross section in pp collisions at root s=7 and 8 TeV and search for anomalous triple gauge couplings at root s=8 TeV

Peer reviewe

Aligning the CMS Muon Chambers with the Muon Alignment System during an Extended Cosmic Ray Run

Peer reviewe

Search for Supersymmetry in pp Collisions at root s=13 TeV in the Single-Lepton Final State Using the Sum of Masses of Large-Radius Jets

Peer reviewe