Mass variance from archival X-ray properties of Dark Energy Survey Year-1 galaxy clusters. Issue 3 (26th September 2019)

• Record Type: Journal Article
• Authors: Farahi, A; Chen, X; Evrard, A E; Hollowood, D L; Wilkinson, R; Bhargava, S; Giles, P; Romer, A K; Jeltema, T; Hilton, M; Bermeo, A; Mayers, J; Vergara Cervantes, C; Rozo, E; Rykoff, E S; Collins, C; Costanzi, M; Everett, S; Liddle, A R; Mann, R G; Mantz, A; Rooney, P; Sahlen, M; Stott, J; Viana, P T P; Zhang, Y; Annis, J; Avila, S; Brooks, D; Buckley-Geer, E; Burke, D L; Carnero Rosell, A; Carrasco Kind, M; Carretero, J; Castander, F J; da Costa, L N; De Vicente, J; Desai, S; Diehl, H T; Dietrich, J P; Doel, P; Flaugher, B; Fosalba, P; Frieman, J; García-Bellido, J; Gaztanaga, E; Gerdes, D W; Gruen, D; Gruendl, R A; Gschwend, J; Gutierrez, G; Honscheid, K; James, D J; Krause, E; Kuehn, K; Kuropatkin, N; Lima, M; Maia, M A G; Marshall, J L; Melchior, P; Menanteau, F; Miquel, R; Ogando, R L C; Plazas, A A; Sanchez, E; Scarpine, V; Schubnell, M; Serrano, S; Sevilla-Noarbe, I; Smith, M; Sobreira, F; Suchyta, E; Swanson, M E C; Tarle, G; Thomas, D; Tucker, D L; Vikram, V; Walker, A R; Weller, J;
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 490:Issue 3(2019)
• Page Start: 3341
• Page End: 3354
• Publication Date: 2019-09-26
• Subjects: galaxies: clusters: general -- X-rays: galaxies: clusters; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stz2689
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: Using archival X-ray observations and a lognormal population model, we estimate constraints on the intrinsic scatter in halo mass at fixed optical richness for a galaxy cluster sample identified in Dark Energy Survey Year-One (DES-Y1) data with the redMaPPer algorithm. We examine the scaling behaviour of X-ray temperatures, T X, with optical richness, λRM, for clusters in the redshift range 0.2 < z < 0.7. X-ray temperatures are obtained from Chandra and XMM observations for 58 and 110 redMaPPer systems, respectively. Despite non-uniform sky coverage, the TX measurements are $\gt 50{{\ \rm per\ cent}}$ complete for clusters with λRM > 130. Regression analysis on the two samples produces consistent posterior scaling parameters, from which we derive a combined constraint on the residual scatter, $\sigma _{\ln T \, |\, \lambda }= 0.275 \pm 0.019$ . Joined with constraints for T X scaling with halo mass from the Weighing the Giants program and richness–temperature covariance estimates from the LoCuSS sample, we derive the richness-conditioned scatter in mass, $\sigma _{\ln M \, |\, \lambda }= 0.30 \pm 0.04\, _{({\rm stat})} \pm 0.09\, _{({\rm sys})}$, at an optical richness of approximately 100. Uncertainties in external parameters, particularly the slope and variance of the T X –mass relation and the covariance of T X and λRM at fixed mass, dominate the systematic error. The $95{{\ \rm per\ cent}}$ confidence region from joint sample analysis is relatively broad, $\sigma _{\ln M \, |\, \lambda }\in [0.14, \, 0.55]$, or a factor 10 in variance.