Mass variance from archival X-ray properties of Dark Energy Survey Year-1 galaxy clusters

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.; Garcia-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.

doi:10.1093/mnras/stz2689

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, TX, 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 > 50 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, σln T | λ = 0.275 ± 0.019. Joined with constraints for TX 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, σln M | λ = 0.30 ± 0.04 (stat) ± 0.09 (sys), at an optical richness of approximately 100. Uncertainties in external parameters, particularly the slope and variance of the TX-mass relation and the covariance of TX and λRM at fixed mass, dominate the systematic error. The 95 per cent confidence region from joint sample analysis is relatively broad, σln M | λ ∈ [0.14, 0.55], or a factor 10 in variance.

Mass variance from archival X-ray properties of Dark Energy Survey Year-1 galaxy clusters / 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.; Garcia-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.. - In: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY. - ISSN 0035-8711. - 490:3(2019), pp. 3341-3354. [10.1093/mnras/stz2689]