Activity and quiescence in early cluster environments Veronica - PowerPoint PPT Presentation

Activity and quiescence in early cluster environments Veronica Strazzullo (LMU USM) E. Daddi, R. Gobat, F . Valentino, M. Pannella, A. Cimatti, M. Dickinson, A. Renzini, G. Brammer, M. Onodera, A. Finoguenov, M. Bethermin, A. Zanella, M. Carollo, N. Arimoto High-redshift (proto-)clusters: anecdotal or important phase? - Paris, Oct. 2016

Cluster galaxies at z ≳ 1.5 – the SF vs quiescent views On-going star formation Some fraction of already evolved even deep into cluster cores galaxies in the core population (Tran+2010, Hayashi+2010, Santos+2011, Fassbender+2011, Stanford+2012, Zeimann+2012, Brodwin+2013, Alberts 2013, Bayliss+2014, Stacey+2014, Ma+2014, Santos+2015, Alberts+2016, …) (Kurk+2009, Papovich+2010, Andreon+2011, 2014, Spitler+2012, Stanford+2012, Zeimann+2012, Tadaki+2012,Tanaka+2013ab, Strazzullo+2013, Newman+2014, Brodwin+ 2013 Cooke+2015, … ) Newman+ 2014

…in some cases, within the same cluster CIG J0218-0510, z=1.6 (Papovich+2010, Tanaka+2010, Tran+2010, 2015, Rudnick+2012, Smail+2014, Santos+2014, …) Smail+2014 Papovich+2010 Tran+2010 Tran+2015

What was the forecast…? Observations to z~1: Simulations: Fossil record (z~0): Mei+ 2009 De Lucia+ 2006 U-B Thomas+2005 Observations to z>2: M B Fossil record (z~1): Gobat+2008

Cluster diversity and/or mass dependence? Dependence of galaxy population properties on cluster mass are possible/likely, but younger populations and/or high SF levels found also in very massive clusters Santos+2015 Stanford+2012

What clusters ? By z ≈ 2, an average mid-10 14 M ◉ today’s cluster is formally well into group regime… Brodwin+2012 Fakhouri+2010

A „typical“ cluster progenitor, Cl J1449+0856 at z=2 (Gobat+2011, 2013, Strazzullo+2013, Valentino+15,16) IR-selected, X-ray detected (Gobat+2011). A low-mass structure typical of a massive cluster progenitor at z~2. • massive quiescent (often morphologically early-type) galaxies in the cluster central region (<200kpc) • at the same time – and in contrast with z<1.5 cluster cores – central regions also host still actively star forming sources Strazzullo+13 Strazzullo+13

A „typical“ cluster progenitor, Cl J1449+0856 at z=2 (Gobat+2011, 2013, Strazzullo+2013, Valentino+15,16) IR-selected, X-ray detected (Gobat+2011). A low-mass structure typical of a massive cluster progenitor at z~2. • massive quiescent (often morphologically early-type) galaxies in the cluster central region (<200kpc) • at the same time – and in contrast with z<1.5 cluster cores – central regions also host still actively star forming sources Strazzullo+13

A further look at galaxy populations in Cl J1449+0856: 200 kpc Strazzullo+in prep.

Red sequence seeds at z~2 A clear, small population of red sources …

Red sequence seeds at z~2 … mostly seemingly quiescent galaxies

Red sequence seeds at z~2 … clearly segregated deep into the cluster center r<150 kpc

Red sequence seeds at z~2 (… independent of photo-zs… ) Statistically subtracted CMD - (largely) independent of individual membership determination.

Red sequence seeds at z~2 Quite a clear signature of the inner, densest cluster core r<150 kpc Statistically subtracted CMD - (largely) independent of individual membership determination.

Red sequence seeds at z~2

A different viewpoint – a 10x overdensity of ALMA 870 μ m sources Further constrains BCG complex • All but one sources on the bright red-sequence are undetected at • 870 μ m (<2 σ , ~40M ⊙ /yr) ➜ would suggest suppressed SF for most massive red galaxies

A different viewpoint – a 10x overdensity of ALMA 870 μ m sources Further constrains BCG complex • All but one sources on the bright red-sequence are undetected at • 870 μ m (<2 σ , ~40M ⊙ /yr) ➜ would suggest suppressed SF for most massive red galaxies

A different viewpoint – a 10x overdensity of ALMA 870 μ m sources One bright red-sequence source 870 μ m-detected: new cycle 3 observations of CO(4-3) confirm it at the cluster redshift.

BCG building site… SF/suppressed? F105W F140W Ks quiescent r ∼ 1.8“, ~15 kpc 870 μ m-source, ~200 M ⊙ /yr At the cluster center, a complex of multiple sources, apparently a mixture of star-forming and suppressed/quiescent galaxies, is likely the future BCG still in its build-up phase.

In densest regions of (one, supposedly) ordinary cluster progenitor • environment(s), some massive galaxies are already evolved and make for a first red sequence seedling at z~2. This population is confined to the very central cluster region. Star formation is still occurring even deep into the cluster core - • different selections and observations highlight different aspects of a likely diverse galaxy population . Among the points deserving further thought: the link between suppression of star formation and densest • environments at this redshift - this tells something more/different than environmental effects due to few/several billion years spent in a massive hot halo stellar populations of passive cluster galaxies vs field analogs -- at z ≈ 2 •

Quick ad – Galaxy populations in the high-z SPT tail with J. Mohr, M. Pannella, A. Saro, M. Ashby, S.A. Stanford and SPT-clusters Following up on two crucial issues (for galaxy population studies): probe established, massive clusters, at the high extreme of the density range • avoid cluster selection biases involving galaxy population properties • SPT-SZ 2500 deg 2 ROSAT-All sky Planck-DR1 -1 ] • h 70 ACT 10 M 500c [10 14 M O Bleem+2015 1 0.0 0.5 1.0 1.5 Redshift Five very massive (M 200 ≳ 5x10 14 M ⊙ ) SZ-selected clusters at z ≥ 1.4 (only very few confirmed such massive structures found to date at this redshift, by different means (X-ray, SZ, red galaxies, Rosati+2009, Santos+2011/Tozzi+2015, Stanford+2012/ Brodwin+2012,2015, Andreon+2009,2014, Bleem+2015/Bayliss+2014, Mantz+2015)

Quick ad – Galaxy populations in the high-z SPT tail with J. Mohr, M. Pannella, A. Saro, M. Ashby, S.A. Stanford and SPT-clusters Following up on two crucial issues (for galaxy population studies): probe established, massive clusters, at the high extreme of the density range • avoid cluster selection biases involving galaxy population properties • • A complete sample of massive distant clusters over 2500 deg 2 , among the few most massive clusters known at these redshifts • Cluster selection independent of cluster galaxies - ideally suited for galaxy populations studies High cluster mass ideal for probing environmental effects on galaxy • populations in most massive haloes, and to improve statistics A dedicated deep optical/NIR follow-up with HST (F105+F140, 2+1 • orbits) & Spitzer (3.6+4.5 𝜈 m, 6000-8000s per channel).

A first, „minimal“ 4-bands study… Stellar mass assembly Star formation and Structural evolution quenching • restframe NIR LF down • morphological vs. stellar to M*+3 quiescent fraction population properties in • • stellar mass function environmental dense environments • and mass assembly at dependence of stellar • mass-size relation and z>1.3 populations environmental red sequence evolution dependence • Wang+ 2016 Wylezalek+2014 Composite LF simulation Alberts+ 2016 Newman+2014

first-look, preliminary! z~1.7 z~1.5 z~1.4

SPT-CLJ2040 full WFC3 field z=1.48 core (<280 kpc) >280 kpc