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

Molecular Landscape and Actionable Alterations in a Genomically Guided Cancer Clinical Trial: National Cancer Institute Molecular Analysis for Therapy Choice (NCI-MATCH).

PURPOSE: Therapeutically actionable molecular alterations are widely distributed across cancer types. The National Cancer Institute Molecular Analysis for Therapy Choice (NCI-MATCH) trial was designed to evaluate targeted therapy antitumor activity in underexplored cancer types. Tumor biopsy specimens were analyzed centrally with next-generation sequencing (NGS) in a master screening protocol. Patients with a tumor molecular alteration addressed by a targeted treatment lacking established efficacy in that tumor type were assigned to 1 of 30 treatments in parallel, single-arm, phase II subprotocols. PATIENTS AND METHODS: Tumor biopsy specimens from 5,954 patients with refractory malignancies at 1,117 accrual sites were analyzed centrally with NGS and selected immunohistochemistry in a master screening protocol. The treatment-assignment rate to treatment arms was assessed. Molecular alterations in seven tumors profiled in both NCI-MATCH trial and The Cancer Genome Atlas (TCGA) of primary tumors were compared. RESULTS: Molecular profiling was successful in 93.0% of specimens. An actionable alteration was found in 37.6%. After applying clinical and molecular exclusion criteria, 17.8% were assigned (26.4% could have been assigned if all subprotocols were available simultaneously). Eleven subprotocols reached their accrual goal as of this report. Actionability rates differed among histologies (eg, \u3e 35% for urothelial cancers and \u3c 6% for pancreatic and small-cell lung cancer). Multiple actionable or resistance-conferring tumor mutations were seen in 11.9% and 71.3% of specimens, respectively. Known resistance mutations to targeted therapies were numerically more frequent in NCI-MATCH than TCGA tumors, but not markedly so. CONCLUSION: We demonstrated feasibility of screening large numbers of patients at numerous accruing sites in a complex trial to test investigational therapies for moderately frequent molecular targets. Co-occurring resistance mutations were common and endorse investigation of combination targeted-therapy regimens

Dark energy constraints from the thermal Sunyaev–Zeldovich power spectrum

International audienceWe constrain the dark energy equation of state parameter, $${w}$$, using the power spectrum of the thermal Sunyaev–Zeldovich (tSZ) effect. We improve upon previous analyses by taking into account the trispectrum in the covariance matrix and marginalizing over the foreground parameters, the correlated noise, the mass bias B in the Planck universal pressure profile, and all the relevant cosmological parameters (i.e. not just Ω_m and σ_8). We find that the amplitude of the tSZ power spectrum at ℓ ≲ 10^3 depends primarily on F ≡ σ_8(Ω_m/B)^0.40h^−0.21, where B is related to more commonly used variable b by B = (1 − b)^−1. We measure this parameter with 2.6 per cent precision, F = 0.460 ± 0.012 (68 per cent CL). By fixing the bias to B = 1.25 and adding the local determination of the Hubble constant H_0 and the amplitude of the primordial power spectrum constrained by the Planck cosmic microwave background (CMB) data, we find $${w}$$ = −1.10 ± 0.12, σ_8 = 0.802 ± 0.037, and Ω_m = 0.265 ± 0.022 (68 per cent CL). Our limit on $${w}$$ is consistent with and is as tight as that from the distance-alone constraint from the CMB and H_0. Finally, by combining the tSZ power spectrum and the CMB data we find, in the Λ cold dark mattermodel, the mass bias of B = 1.71 ± 0.17, i.e. 1 − b = 0.58 ± 0.06 (68 per cent CL)

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

Confirmation of NIKA2 investigation of the Sunyaev-Zel’dovich effect by using synthetic clusters of galaxies

The NIKA2 Sunyaev-Zel’dovich Large Program (SZLP) is focused on mapping the thermal SZ signal of a representative sample of selected Planck and ACT clusters spanning the redshift range 0.5 < z < 0.9. Hydrodynamical N-body simulations prove to be a powerful tool to endorse NIKA2 capabilities for estimating the impact of IntraCluster Medium (ICM) disturbances when re- covering the pressure radial profiles. For this goal we employ a subsample of objects, carefully extracted from the catalog Marenostrum MUltidark SImulations of galaxy Clusters (MUSIC), spanning equivalent redshift and mass ranges as the LPSZ. The joint analysis of real observations of the tSZ with NIKA2 and Planck enables to validate the NIKA2 pipeline and to estimate the ICM pressure profiles. Moreover, the possibility to identify a priori the dynamical state of the selected synthetic clusters allows us to verify the impact on the recovered ICM profile shapes and their scatters. Morphological analysis of maps of the Compton parameter seems to be a way to observationally segregate the sample based on the dynamical state in relaxed and disturbed synthetic clusters

Confirmation of NIKA2 investigation of the Sunyaev-Zel’dovich effect by using synthetic clusters of galaxies

The NIKA2 Sunyaev-Zel’dovich Large Program (SZLP) is focused on mapping the thermal SZ signal of a representative sample of selected Planck and ACT clusters spanning the redshift range 0.5 < z < 0.9. Hydrodynamical N-body simulations prove to be a powerful tool to endorse NIKA2 capabilities for estimating the impact of IntraCluster Medium (ICM) disturbances when re- covering the pressure radial profiles. For this goal we employ a subsample of objects, carefully extracted from the catalog Marenostrum MUltidark SImulations of galaxy Clusters (MUSIC), spanning equivalent redshift and mass ranges as the LPSZ. The joint analysis of real observations of the tSZ with NIKA2 and Planck enables to validate the NIKA2 pipeline and to estimate the ICM pressure profiles. Moreover, the possibility to identify a priori the dynamical state of the selected synthetic clusters allows us to verify the impact on the recovered ICM profile shapes and their scatters. Morphological analysis of maps of the Compton parameter seems to be a way to observationally segregate the sample based on the dynamical state in relaxed and disturbed synthetic clusters

PRISM (Polarized Radiation Imaging and Spectroscopy Mission): an extended white paper

Contains fulltext : 126057.pdf (preprint version ) (Open Access