A Strongly Lensed Massive Quiescent Galaxy at z=2.63: of

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1 A Strongly Lensed Massive Quiescent Galaxy at z=2.63: of Drew Newman Carnegie for Science November 17, 2015 / Yale Collaborators: Sirio Belli, Richard Ellis

2 Resolving the of z > 2 quiescent galaxies Are high-z quiescent galaxies commonly disk-like?" Angular momentum fundamental and is a major focus of z=0 IFS surveys, but never measured at z >~ 2" van der Wel Chang+ 2013a,b

3 Resolving the of z > 2 quiescent galaxies Are high-z quiescent galaxies commonly disk-like?" Angular momentum fundamental and is a major focus of z=0 IFS surveys, but never measured at z >~ 2" z = 2 z = 0 Calibration of virial masses" β likely evolves: need spatially-resolved kinematics to measure" Mvirial = β σ 2 R e G Possible tension with Salpeter IMF at z ~ 2; is this real?" Belli, Newman & Ellis 2014

4 Resolving the of z > 2 quiescent galaxies Are high-z quiescent galaxies commonly disk-like?" Angular momentum fundamental and is a major focus of z=0 IFS surveys, but never measured at z >~ 2" Calibration of virial masses" β likely evolves: need spatially-resolved kinematics to measure" Mvirial = β σ 2 R e G Possible tension with Salpeter IMF at z ~ 2; is this real?" van Dokkum Barro Comparison with candidate progenitors and merger simulations" van Dokkum et al 2015: Rapid rotation in compact star formation galaxies at z=2-3" Wuyts et al 2010: Remnants of gas-rich mergers should retain significant rotation"

5 Generally no emission lines" " Sources very compact" R e ~ , barely resolved with HST! Very difficult with seeing-limited observations" WFC3 grism resolution too low for kinematics" à No resolved kinematics of quiescent galaxies beyond z~1"

6 for lensed red galaxies at z ~ 2 Gravitational lensed examples would be particularly useful for compact galaxies" Many lenses known, dominated by low/intermediate mass blue systems" Excep0ons: Muzzin et al 2012, Geier et al 2013 A tailored search in the NIR is needed, focusing on bright lensed galaxies with red NIR colors" Underway with Magellan/ FourStar and HST archive" Stark+ 2013

7 ApJL 813, L7, Nov Search of the HST/WFC3 archive revealed an extremely bright (Ks = 19.2 AB ~ 1 CB58 ) red galaxy triply imaged by MACSJ (Snapshot program with P.I. H. Ebeling)

8 A massive, compact galaxy R e = 1.8 ± 0.4 kpc n = 3.5 ± 0.9 The lensed galaxy is remarkably massive quiescent galaxies at this redshij). (log M = ) and compact (as typical of

9 Recently, rapidly quenched z=2.636 Age = 760 ± 50 Myr, z form = 3.7 (for exponen@al history) Current SFR = 2 ± 1 M /yr σ = 271 ± 41 km/s

10 Measuring resolved stellar (source plane) (image plane) Spectra are sufficient to measure rotation using stellar absorption lines (first beyond z~1.3)" Velocity [km s 1 ] Flux profile <R/R e >= Magellan/FIRE Keck/MOSFIRE Mean Model: With obs. effects Without Position along image [arcsec] Consistent independent measurements from " Kinematics analyzed with two-integral Jeans model accounting for lensing and observational effects:" log M dyn = ± 0.14" V max = 189 ± 34 km/s (projected)"

11 support V / σ z=2.6 RG1M0150 z~1 vd Wel & vd Marel (2008) z=0 ATLAS 3D M Chab < z=0 ATLAS 3D M Chab > Wuyts et al (2010) simulations Edge on isotropic oblate rotators [ε / (1 ε)] Ellipticity ε V/σ = 0.70 ± 0.21 is rather high considering the round projected shape (b/a = 0.88 ± 0.06)" For i=35 : ε=0.44 and V max =330 km/s" This galaxy is near the upper envelope of local ETGs on the ε vs. V/σ diagram." Similar to z~1 ETGs from vd Wel & vd Marel (2008)" Consistent with predictions of merger simulations of gas-rich disks that produce compact, rotating remnants (Wuyts et al 2010)" Local ETGs in this mass range are slow rotators. " Are mergers responsible for size & mass growth capable of reducing the net angular momentum? "

12 Future steps Sample of ~5 velocity gradient targets with data in hand" Age gradients" Could be used to distinguish formation histories (see talk by S. Wellons)" Extremely bright new arc recently discovered " 10x brighter than MACSJ0150" Extremely high quality spectrum suitable to derive" [Fe/H] and [α/fe], perhaps stellar metallicity gradient" Star-formation timescale" Resolved σ(r) and calibration of virial mass estimator at z~2"