Gravitational redshifting of galaxies in the SPIDERS cluster catalogue

Abstract

Data from the SPectroscopic IDentification of ERosita Sources (SPIDERS) are searched for a detection of the gravitational redshifting of light from $\sim 20000$ galaxies in $\sim 2500$ galaxy clusters using three definitions of the cluster centre: its Brightest Cluster Galaxy (BCG), the redMaPPer identified Central Galaxy (CG), or the peak of X-ray emission. Distributions of velocity offsets between galaxies and their host cluster's centre, found using observed redshifts, are created. The quantity $\hat{\Delta }$, the average of the radial velocity difference between the cluster members and the cluster systemic velocity, reveals information on the size of a combination of effects on the observed redshift, dominated by gravitational redshifting. The change of $\hat{\Delta }$ with radial distance is predicted for SPIDERS galaxies in General Relativity (GR), and $f(R)$ gravity, and compared to the observations. The values of $\hat{\Delta }=-13.5\pm 4.7$ km s${}^{-1}$, $\hat{\Delta }=-12.5\pm 5.1$ km s${}^{-1}$, and $\hat{\Delta }=-18.6\pm 4.8$ km s${}^{-1}$ for the BCG, X-ray and CG cases respectively broadly agree with the literature. There is no significant preference of one gravity theory over another, but all cases give a clear detection ($>2.5\sigma$) of $\hat{\Delta }$. The BCG centroid is deemed to be the most robust method in this analysis, due to no well defined central redshift when using an X-ray centroid, and CGs identified by redMaPPer with no associated spectroscopic redshift. For future gravitational redshift studies, an order of magnitude more galaxies, $\sim 500000$, will be required-a possible feat with the forthcoming Vera C. Rubin Observatory, Euclid and eROSITA.

arXiv commentAccepted for publication in MNRAS. 11 pages, 10 figures

References in corpus (39)

• The Seventh Data Release of the Sloan Digital Sky Survey
• LSST: from Science Drivers to Reference Design and Anticipated Data Products
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
• Simulations of X-ray Clusters
• The Multi-Object, Fiber-Fed Spectrographs for SDSS and the Baryon Oscillation Spectroscopic Survey
• Cold dark matter haloes in the Planck era: evolution of structural parameters for Einasto and NFW profiles
• Euclid Definition Study Report
• The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Overview and Early Data
• redMaPPer I: Algorithm and SDSS DR8 Catalog
• Linear Regression for Astronomical Data with Measurement Errors and Intrinsic Scatter
• Properties of spherical galaxies and clusters with an NFW density profile
• MAMPOSSt: Modelling Anisotropy and Mass Profiles of Observed Spherical Systems. I. Gaussian 3D velocities
• The SDSS DR6 Luminosity Functions of Galaxies
• New constraints on $f(R)$ gravity from clusters of galaxies
• Dynamical Masses in Modified Gravity
• Gravitational redshift of galaxies in clusters as predicted by general relativity
• The Mean and Scatter of the Velocity Dispersion-Optical Richness Relation for maxBCG Galaxy Clusters
• SDSS-V: Pioneering Panoptic Spectroscopy
• The universal distribution of halo interlopers in projected phase space. Bias in galaxy cluster concentration and velocity anisotropy?
• SPIDERS: the spectroscopic follow-up of X-ray selected clusters of galaxies in SDSS-IV
• Optical Substructure and BCG Offsets of Sunyaev-Zel'dovich and X-ray Selected Galaxy Clusters
• CODEX clusters. The Survey, the Catalog, and Cosmology of the X-ray Luminosity Function
• How does our choice of observable influence our estimation of the centre of a galaxy cluster? Insights from cosmological simulations
• Measuring Gravitational Redshifts in Galaxy Clusters
• Gravity theories, Transverse Doppler and Gravitational Redshifts in Galaxy Clusters
• Galaxy cluster lensing masses in modified lensing potentials
• Gravitational Redshift of Galaxies in Clusters from the Sloan Digital Sky Survey and the Baryon Oscillation Spectroscopic Survey
• Brightest Cluster Galaxies: the centre can(not?) hold
• Gravitational redshift and asymmetric redshift-space distortions for stacked clusters
• Cluster gas fraction as a test of gravity
• Probing the dark matter issue in f(R)-gravity via gravitational lensing
• SPIDERS: overview of the X-ray galaxy cluster follow-up and the final spectroscopic data release
• A general framework to test gravity using galaxy clusters III: Observable-mass scaling relations in $f(R)$ gravity
• Clusters and superclusters of galaxies
• 4MOST Consortium Survey 5: eROSITA Galaxy Cluster Redshift Survey
• Mass Calibration of the CODEX Cluster Sample using SPIDERS Spectroscopy -- II. The X-ray Luminosity-Mass Relation
• The dark outside: the density profile of dark matter haloes beyond the virial radius
• Reinventing the slide rule for redshifts: the case for logarithmic wavelength shift

Cited by in corpus (10)

• Detectability of the gravitational redshift effect from the asymmetric galaxy clustering
• Testing General Relativity: new measurements of gravitational redshift in galaxy clusters
• Cosmological test of local position invariance from the asymmetric galaxy clustering
• X-ray cluster cosmology
• The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar and APOGEE-2 Data
• Gravitational Redshift from Galaxy Clusters -- a Relativistic Approach
• Observing gravitational redshift with X-Ray emission in galaxy clusters with Athena X-IFU
• Cluster gravitational redshifts: uncertainties and survey requirements
• Active galactic nuclei and gravitational redshifts
• Gravitational redshift from large-scale structure: nonlinearities, antisymmetries, and the dipole