KMOS on VLT. Roger L. Davies. IAU 311, 23 rd July 2014

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1 KMOS on VLT Roger L. Davies IAU 311, 23 rd July 2014

2 Outline What is KMOS? KROSS field galaxy survey KMOS cluster galaxy survey

3 KMOS on VLT PI: Ray Sharples (Durham) Ralf Bender, Alex Agudo Berbel, Richard Bennett, Naidu Bezawada, Roberto Castillo, Michele Cirasuolo, Paul Clark, George Davidson, Richard Davies, Roger Davies, Marc Dubbeldam, Alasdair Fairley, Gert Finger, Natascha Förster Schreiber, Reinhard Genzel, Reinhold Haefner, Achim Hess, Ives Jung, Ian Lewis, David Montgomery, John Murray, Bernard Muschielok, Jeff Pirard, Suzanne Ramsey, Phil Rees, Josef Richter, David Robertson, Ian Robson, Stephen Rolt, Roberto Saglia, Ivo Saviane, Joerg Schlichter, Linda Schmidtobreik, Alex Segovia, Alain Smette, Matthias Tecza, Stephen Todd, Michael Wegner, Erich Wiezorrek Durham UK ATC Oxford MPE USM ESO

4 KMOS on VLT Requirement Instrument Throughput Wavelength coverage Value YJ>20%, H>30%, K>30% 0.85 to 2.5 μm Spectral Resolution Number of IFUs 24 R>3300,3400,3800,3800 (IZ,YJ,H,K) Extent of each IFU Spatial Sampling Patrol field Close packing of IFUs Closest approach of IFUs 2.8 x 2.8 sq. arc seconds 0.2 arc seconds 7.2 diameter field 3 within 1 sq arcmin 2 pairs separated by 6 arcsec

5 KMOS Redshift One Spectroscopic Survey GTO survey of ~1000, z~1, star forming galaxies The team: PIs: Richard Bower/Martin Bureau Co-Is: Andy Bunker, Georgios Magdis, Helen Johnson, Mark Swinbank, Ian Smail, Ray Sharples, John Stott, Alfie Tiley. from Durham & Oxford

6 KROSS science goals What drives the increase in SFRD to z=1-2? Mergers? Major or minor? Secular process? Gas infall rates? KROSS will measure: Disc fraction Merger fraction Tully-Fisher relation Dynamical masses Gas fraction, metallicity gradients, winds & outflows.

7 SFR vs Mass : Hα Stott et al in prep

8 v/σ vs SFR NB. This is from Hα emission! Stott et al in prep

9 Rotational support vs. SFR & z NB. This is from Hα emission! Stott et al in prep

10 KMOS Cluster Survey The team: PIs: Roger Davies / Ralf Bender Co-Is: Alessandra Beifiori, Michele Cappellari, Ryan Houghton, Trevor Mendel, Dave Wilman, Jeffrey Chan, Roberto Saglia, Ray Sharples, Russell Smith, John Stott. from Durham, USM, MPE, Oxford

11 The problem Local rich clusters abundant in red & dead ETGs and deficient in spirals (Dressler 1980, 1997) Stars in ETGs formed 6-10 Gyrs ago (1<z<4) over a short timescale from metal rich gas. (Thomas+05, Sanchez-Blazquez+06,09; Trager+08;Houghton+12) High-z ETGs more compact (Trujillo+07, van der Wel+14) What caused the star formation to shut down? What processes removed the spirals and created ETGs?

12 Goals Stellar population studies of V-band indices at z=1.5 Ages: Coeval or dispersed formation? Global or isolated quenching? Abundances: Fe and Mg - star formation timescales and enrichment Gas distribution, kinematics and composition cf.stars Dynamical and stellar population masses: DM / IMF constraints. What caused the star formation to shut down? What processes removed the spirals and created ETGs?

13 WFC3 grism results (e.g. Newman+13) JKCS041 z=1.8 cluster Low res grism spectra, 19 galaxies observed, 15 quiescent logm>11: age ~1.5Gyrs logm= : age ~0.9Gyrs

14 The clusters Selected 4 high-z clusters with HST imaging: RCS , z=1.04 CaH+K to Mgb in IZ RCS Jee et al 2011

15 The clusters Selected 4 high-z clusters with HST imaging: RCS , z=1.04 CaH+K to Mgb in IZ XMMUJ z=1.39 XMMXCSJ z= 1.46 Cl z=1.6 all with V-band features in YJ Aim for Absorption line spectra of 80 galaxies xmmuj2235/index.html#relatedpaper

16 The galaxies Galaxies are selected to be on the red sequence with a magnitude limit: Attempted mass selection to log M * = 10.7 (from B&C03 models - blue line) XMMU J H<22.5 >20 galaxies per cluster with S/N>5 per pixel Cluster parent sample (by red colour)

17 Oct/Nov 2013:18 half nights Preliminary results on: XMMUJ z=1.39 & Cl z=1.6 ~18hrs on source for 20 galaxies in XMMUJ2235 Typical galaxy fainter than read noise (t=450s) Reducing background systematics to the single count level is difficult

18 Credit: Trevor Mendel Some spectra

19 Credit: Russell Smith XMMUJ z= galaxy stack

20 Offset continuum and ionised emission Credit: Ryan Houghton J=21.4 J=21.9 J=21.0

21 XMMUJ2235 z= 1.39 J & K