10.1093-mnras-stx594.pdf (1.37 MB)
Optical–SZE scaling relations for DES optically selected clusters within the SPT-SZ survey
journal contribution
posted on 2023-06-09, 06:11 authored by Kathy RomerKathy Romer, The DES CollaborationWe study the Sunyaev–Zel'dovich effect (SZE) signature in South Pole Telescope (SPT) data for an ensemble of 719 optically identified galaxy clusters selected from 124.6 deg² of the Dark Energy Survey (DES) science verification data, detecting a clear stacked SZE signal down to richness ? ~ 20. The SZE signature is measured using matched-filtered maps of the 2500 deg2 SPT-SZ survey at the positions of the DES clusters, and the degeneracy between SZE observable and matched-filter size is broken by adopting as priors SZE and optical mass–observable relations that are either calibrated using SPT-selected clusters or through the Arnaud et al. (A10) X-ray analysis. We measure the SPT signal-to-noise ?–? relation and two integrated Compton-yY500–? relations for the DES-selected clusters and compare these to model expectations that account for the SZE–optical centre offset distribution. For clusters with ? > 80, the two SPT-calibrated scaling relations are consistent with the measurements, while for the A10-calibrated relation the measured SZE signal is smaller by a factor of 0.61 ± 0.12 compared to the prediction. For clusters at 20 < ? < 80, the measured SZE signal is smaller by a factor of ~0.20–0.80 (between 2.3s and 10s significance) compared to the prediction, with the SPT-calibrated scaling relations and larger ? clusters showing generally better agreement. We quantify the required corrections to achieve consistency, showing that there is a richness-dependent bias that can be explained by some combination of (1) contamination of the observables and (2) biases in the estimated halo masses. We also discuss particular physical effects associated with these biases, such as contamination of ? from line-of-sight projections or of the SZE observables from point sources, larger offsets in the SZE-optical centring or larger intrinsic scatter in the ?–mass relation at lower richnesses.
Funding
Astronomy Centre Rolling Grant; G0679; STFC-SCIENCE AND TECHNOLOGY FACILITIES COUNCIL; ST/F002858/1
History
Publication status
- Published
File Version
- Published version
Journal
Monthly Notices of the Royal Astronomical SocietyISSN
0035-8711Publisher
WileyExternal DOI
Issue
3Volume
468Page range
3347-3360Department affiliated with
- Physics and Astronomy Publications
Research groups affiliated with
- Astronomy Centre Publications
Full text available
- Yes
Peer reviewed?
- Yes
Legacy Posted Date
2017-05-08First Open Access (FOA) Date
2017-05-08First Compliant Deposit (FCD) Date
2017-05-08Usage metrics
Categories
No categories selectedKeywords
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC