English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Using a magnitude-limited, spectroscopic survey of the X-ray luminous galaxycluster MS1054-03, we isolate 153 cluster galaxies and measure MS1054'sredshift and velocity dispersion to be z=0.8307 and sigma_z=1156 km/s. Theabsorption-line, post-starburst (``E+A''), and emission-line galaxiesrespectively make up 63%, 15%, and 23% of the cluster population. Withphotometry from HST/ACS, we find that the absorption-line members define anexceptionally tight red sequence over a span of ~3.5 magnitudes in i775: theirintrinsic scatter in (V-i) color is only 0.048, corresponding to a (U-B)_zscatter of 0.041. Their color scatter is comparable to that of the ellipticals(sigma_Vi=0.055), but measurably smaller than that of the combined E+S0 sample(sigma_Vi=0.072). The color scatter of MS1054's absorption-line population isapproximately twice that of the ellipticals in Coma; this difference isconsistent with passive evolution where most of the absorption-line members(>75%) formed by z~2, and all of them by z~1.2. For red members, we find atrend (>95% confidence) of weakening Hdelta absorption with redder colors thatwe conclude is due to age: in MS1054, the color scatter on the red sequence isdriven by differences in mean stellar age of up to ~1.5 Gyr. We also generatecomposite spectra and estimate that the average S0 in MS1054 is ~0.5-1 Gyryounger than the average elliptical; this difference in mean stellar age ismainly due to a number of S0s that are blue (18%) and/or are post-starburstsystems (21%).Comment: Accepted by Ap

A Keck Spectroscopic Survey of MS 1054−03 (z= 0.83): Forming the Red Sequence