SPIDERS: overview of the X-ray galaxy cluster follow-up and the final spectroscopic data release. Issue 3 (15th July 2020)

• Record Type: Journal Article
• Authors: Clerc, N; Kirkpatrick, C C; Finoguenov, A; Capasso, R; Comparat, J; Damsted, S; Furnell, K; Kukkola, A E; Ider Chitham, J; Merloni, A; Salvato, M; Gueguen, A; Dwelly, T; Collins, C; Saro, A; Erfanianfar, G; Schneider, D P; Brownstein, J; Mamon, G A; Padilla, N; Jullo, E; Bizyaev, D
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 497:Issue 3(2020)
• Page Start: 3976
• Page End: 3992
• Publication Date: 2020-07-15
• Subjects: galaxies: clusters: general -- cosmology: observations -- X-rays: galaxies: clusters; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/staa2066
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: SPIDERS (The SPectroscopic IDentification of eROSITA Sources) is a large spectroscopic programme for X-ray selected galaxy clusters as part of the Sloan Digital Sky Survey-IV (SDSS-IV). We describe the final data set in the context of SDSS Data Release 16 (DR16): the survey overall characteristics, final targeting strategies, achieved completeness, and spectral quality, with special emphasis on its use as a galaxy cluster sample for cosmology applications. SPIDERS now consists of about 27 000 new optical spectra of galaxies selected within 4000 photometric red sequences, each associated with an X-ray source. The excellent spectrograph efficiency and a robust analysis pipeline yield a spectroscopic redshift measurement success rate exceeding 98 per cent, with a median velocity accuracy of 20 km s −1 (at z = 0.2). Using the catalogue of 2740 X-ray galaxy clusters confirmed with DR16 spectroscopy, we reveal the 3D map of the galaxy cluster distribution in the observable Universe up to z ∼ 0.6. We highlight the homogeneity of the member galaxy spectra among distinct regions of the galaxy cluster phase space. Aided by accurate spectroscopic redshifts and by a model of the sample selection effects, we compute the galaxy cluster X-ray luminosity function and we present its lack of evolution up to z = 0.6. Finally we discuss the prospects of forthcoming large multiplexed spectroscopic programmes dedicated to follow up the next generation of all-sky X-ray source catalogues.