The MUSIC of Galaxy Clusters I: Baryon properties and Scaling Relations of the thermal Sunyaev-Zel'dovich Effect

We introduce the Marenostrum-MultiDark SImulations of galaxy Clusters (MUSIC) Dataset, one of the largest sample of hydrodynamically simulated galaxy clusters with more than 500 clusters and 2000 groups. The objects have been selected from two large N-body simulations and have been resimulated at high resolution using SPH together with relevant physical processes (cooling, UV photoionization, star formation and different feedback processes). We focus on the analysis of the baryon content (gas and star) of clusters in the MUSIC dataset both as a function of aperture radius and redshift. The results from our simulations are compared with the most recent observational estimates of the gas fraction in galaxy clusters at different overdensity radii. When the effects of cooling and stellar feedbacks are included, the MUSIC clusters show a good agreement with the most recent observed gas fractions quoted in the literature. A clear dependence of the gas fractions with the total cluster mass is also evident. The impact of the aperture radius choice, when comparing integrated quantities at different redshifts, is tested: the standard definition of radius at a fixed overdensity with respect to critical density is compared with a definition based on the redshift dependent overdensity with respect to background density. We also present a detailed analysis of the scaling relations of the thermal SZ (Sunyaev Zel'dovich) Effect derived from MUSIC clusters. The integrated SZ brightness, Y, is related to the cluster total mass, M, as well as, the M-Y counterpart, more suitable for observational applications. Both laws are consistent with predictions from the self-similar model, showing a very low scatter. The effects of the gas fraction on the Y-M scaling and the presence of a possible redshift dependence on the Y-M scaling relation are also explored.Comment: 22 pages, 25 figures, accepted for pubblication by MNRA

Characterization and Management of Stable Coronary Artery Disease in Patients Undergoing Transcatheter Aortic Valve Implantation.

Background/Objectives: To date, data regarding the characteristics and management of obstructive, stable coronary artery disease (CAD) encountered in patients undergoing transcatheter aortic valve implantation (TAVI) are sparse. The aim of the study was to analyze granular details, treatment, and outcomes of patients undergoing TAVI with obstructive, stable CAD from real-world practice. Methods: REVASC-TAVI (Management of myocardial REVASCularization in patients undergoing Transcatheter Aortic Valve Implantation with coronary artery disease) is an investigator-initiated, multicenter registry, which collected data from patients undergoing TAVI with obstructive stable CAD found during the pre-TAVI work-up. Results: A total of 2025 patients from 30 centers worldwide with complete follow-up were included in the registry. Most patients had single-vessel CAD (56.1%). An involvement of proximal coronary tracts was detected in 62.5% of cases, with 12.0% of patients having CAD in left main (LM). Most patients received percutaneous coronary intervention (PCI) (n = 1617, 79.9%), especially those with proximal CAD (90.4%). At 2 years, the rates of all-cause death [Kaplan-Meier (KM) estimates 20.1% vs. 18.8%, plog-rank = 0.86] and of the composite of all-cause death, stroke, myocardial infarction, and rehospitalization for heart failure (KM estimates 29.7% vs. 27.5%, plog-rank = 0.82) did not differ between patients undergoing PCI and those who were not. Conclusions: Patients undergoing TAVI with obstructive CAD more commonly had a single-vessel disease and an involvement of proximal coronary tracts. They were commonly treated with PCI, with similar outcomes compared to those treated conservatively

Planck Intermediate Results. XXXVI. Optical identification and redshifts of Planck SZ sources with telescopes at the Canary Islands Observatories

We present the results of approximately three years of observations of Planck Sunyaev-Zeldovich (SZ) sources with telescopes at the Canary Islands observatories as part of the general optical follow-up programme undertaken by the Planck collaboration. In total, 78 SZ sources are discussed. Deep-imaging observations were obtained for most of these sources; spectroscopic observations in either in long-slit or multi-object modes were obtained for many. We effectively used 37.5 clear nights. We found optical counterparts for 73 of the 78 candidates. This sample includes 53 spectroscopic redshift determinations, 20 of them obtained with a multi-object spectroscopic mode. The sample contains new redshifts for 27 Planck clusters that were not included in the first Planck SZ source catalogue (PSZ1).Comment: 15 pages, 14 figures, accepted for publication in A&

VizieR Online Data Catalog: Planck Sunyaev-Zeldovich sources (PSZ2) (Planck+, 2016)

Three pipelines are used to detect SZ clusters: two independent implementations of the Matched Multi-Filter (MMF1 and MMF3), and PowellSnakes (PwS). The main catalogue is constructed as the union of the catalogues from the three detection methods. The completeness and reliability of the catalogues have been assessed through internal and external validation as described in section 4 of the paper. (5 data files)

COMPLEX WEAR MEASUREMENT ON THIN COATINGS BY THE CRATERING METHOD

Ball cratering and rotating wheel tests are useful techniques for abrasive wear resistence evaluation of thin coatings. Nevertheless, such techniques involve significant experimental errors, coming from equipment deficiences and changes in wear response depending on test parameters. In case of rotating wheel test, common instrumental errors are: geometry-induced errors (curved or non-horizontal sample surface), alignment errors (misalignment between ball/wheel axis and sample stage) and optical measurement errors. In the present paper, errors due to crater dimension detection system (penetration depth or crater diameter) and equipment deficiences (rotating axes misalignment and sample slope) were numerically analysed. A general expression form volume calculation was obtained, considering axes misalignment and sample slope, and experimentally validated by wear tests on Ti/TIN CAE-PVD coatings and profilometer abraded volumes measurement. Results showed that axes misaligment and sample slope involve considerable errors in wear coefficient evaluation. However, errors can be corrected by the use of obtained expressions

The evolution of the Y-M scaling relation in MUSIC clusters

This work describes the baryon content and Sunyaev-Zeldovich properties of the MUSIC (Marenostrum-MultiDark SImulations of galaxy clusters) dataset and their evolution with redshift and aperture radius. The MUSIC dataset is one of the largest samples of hydrodynamically simulated galaxy clusters (more than 2000 objects, including more than 500 clusters). We show that when the effects of cooling and stellar feedbacks are properly taken into account, the gas fraction of the MUSIC clusters consistently agrees with recent observational results. Moreover, the gas fraction has a net dependence with the total mass of the cluster and increases slightly with redshift at high overdensities. The study of the Y-M relation confirms the consistence of the self-similar model, showing no evolution with redshift at low overdensities. (C) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei