Nearby Galaxy Evolution with Deep Surveys: Studying galaxies at 1<D<100 Mpc. Eric Peng Peking University

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1 Nearby Galaxy Evolution with Deep Surveys: Studying galaxies at 1<D<100 Mpc Eric Peng Peking University

2 Why 1 < D < 100 Mpc? Need to leave the Local Group for a representative sample of galaxies to study The Coma Cluster (100 Mpc) is the nearest truly massive galaxy cluster Much of what we know about the detailed properties of galaxies is from this distance range (internal stellar populations, kinematics, star formation regions, etc). D (Mpc) 5 kpc 10 pc TRGB+2 (I) GCLF mean(g) milestone M31, nearest MW analog NGC 5128 nearest massive E (pec) Virgo Cluster Coma cluster

3 Galaxies that are too far and too near (Only) partially resolved into stars, HII regions, substructure Large, truly extended sources (many arcmin) Complicates observing strategy, standard data reduction and analysis pipelines Targeted observations are okay, but become special cases in large surveys. D (Mpc) 5 kpc 10 pc TRGB+2 (I) GCLF mean(g) milestone M31, nearest MW analog NGC 5128 nearest massive E (pec) Virgo Cluster Coma cluster

4 Virgo central galaxy, M87 (CFHT)

5 Globular Cluster Systems z=12 GCs form early in the evolution of galaxies Trace early, major epochs of star formation Simple stellar populations (mostly) Observable out to >100 Mpc, massive systems z=0 des ges Moore et al (2006)

6 The Properties of Globular Cluster Systems Specific Frequency: number of GCs normalized to MV=-15 SN = NGC (M V +15) Puzzle: Globular cluster formation efficiency is not constant across galaxy mass Peng et al. (2008)

7 Globular Clusters in Virgo Cluster des: The Role of Environment Dwarfs only: Mz > -19 SN vs clustercentric distance des with high GC fractions are within Dp < 1 Mpc des within 100 kpc, stripped of GCs Peng et al. (2008)

8 The Evolution of Massive Galaxies DeLucia & Blaizot (2007) Observations show little mass evolution in BCGs with redshift In massive clusters, N-body simulations predict that intracluster light dominates the light of the BCG Prediction: Strong correlation between ICL fraction and cluster mass Intracluster Globular Clusters (IGCs) should accompany ICL, and can be easier to see Purcell, Bullock & Zetner (2007)

9 HST/ACS Coma Treasury Survey (Carter et al 2008)

10 Globular clusters easily detected! HST/ACS Coma Treasury Survey (Carter et al 2008)

11 GC spatial distribution in cluster core NGC (R<520kpc) = 70,000 Intergalactic GCs = 47,000 Implied ICL: 27 mag/arcsec 2 ~2500 disrupted des at MV=-16 BH-BH binaries from GCs -> Detectable source of gravitational waves? (Work in progress with Jonathan Downing) Coma core GC distribution Peng et al. (2011) ~70% of GCs in N4874+IGC system are IGCs, ~30-45% of GCs in the core are IGCs Consistent with ICL measurements (Gonzalez et al) and simulations (Purcell et al)

12 CFHT Large Program ( ) 104 sq. deg in ugriz u*g ~26, r i z ~25 PI: L. Ferarrese Galaxies, globular clusters, foreground halo, background clusters Sandbox for future surveys

13 The Next Generation Virgo Survey J.-C. Cuillandre

14 NGVS Status ( )

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17 IGCs in the Virgo Cluster? ICL observations LSB light (Mihos) Planetary nebulae (Arnaboldi, Okamura, Feldmeier) Best galaxy cluster for GC observations Mihos et al (2006)

18 Virgo globular M89 M86 M84 cluster spatial M60 distribution Can we estimate the IGC fraction in Virgo? MMT/Hectospec 6.5 nights (PI: E. Peng) ~1000 confirmed GC velocities confirmed IGCs M49 Preliminary IGC fraction ranges from ~0-40% depending on chosen background region. Need careful treatment of Galactic foreground.

19 Virgo and the Galactic Foreground V. Belokurov

20 Virgo and the Galactic Foreground Virgo Overdensity Virgo GCs Sgr MSTO

21 Resolving Virgo GCs in the NGVS With 0.6 image quality: Many bright GCs in Virgo are resolved Star-galaxy separation becomes difficult at i>24, ~2 mag above photometric limit.

22 Star-GC-galaxy selection Point sources Background galaxies GCs ugi selected point sources Foreground stars The inclusion of u-band is extremely helpful for MW studies

23 Overlap regions r h in g band r h in i band

24 Sizes of Stellar Systems Coma Virgo 0.5 seeing Measuring sizes of stellar systems is important for understanding them Globular clusters are among the smallest stellar systems ELTs+AO may not significantly improve survey speed for GCs in nearby galaxy clusters for certain applications HST and current ground-based facilities can already do a lot HST 30m ELT Misgeld & Hilker (2011)

25 The Telescope Access Program (TAP) CFHT 3.6m Palomar 5m Magellan 2x6.5m MMT 6.5m Eric Peng, Shude Mao, Suijian Xue, Xiaohui Fan, Xiaowei Liu, Junxian Wang, Zhongxiang Wang, Jiasheng Huang, Lin Yan, Haojing Yan, Jiansheng Chen, Paul Ho, Fred Lo Gang Zhao, Timothy Beers, Yu Gao, Qiusheng Gu, Raja Guhathakurta, Lei Hao, Lihwai Lin, Shengbang Qian, Hongchi Wang, Weimin Yuan

26 The Goals for TAP Promote excellent PI-led science. Do this in conjunction with other domestic initiatives (e.g., Lijiang 2.4m). Build a user community for current and future projects (Dome-A, TMT, etc). Build our international competitiveness. We eventually need to be able to compete on the open market in observational astronomy. To increase our ability to build instrumentation, manage projects, and contribute in-kind to future international facilities.

27 TAP Status CFHT (3.6m, 15 nights/year), Palomar Hale (5m, P200, 20 nights/year) MMT (6.5m, 10 nights/year), Magellan (6.5m x 2, 2-4 nights/year) TAP will be for 3 years ( ) 2011B: Oversubscription:1.5-3, 15 programs 2012A: Oversubscription: 1.5-3, 14 programs Next deadline, late-march, 2012 for 2012B

28 TAP and the Community The 1st TAP Workshop for Optical-IR Astronomy in China PKU/KIAA, Feb 2011 We held our first TAP workshop at PKU/KIAA to introduce the program to the community. ~100 participants from all over China International visitors from TAP observatories Discussions on joint science programs TAP Workshop, Feb 2011 Next TAP Workshop being planned for Feb, Call for new CFHT Large Programs ( ), deadline Feb 28, 2012

29 The Next Generation CFHT (from Pat Côté (HIA) and the ngcfht Concept Study Team)

30 The Next Generation CFHT Proposal There is an exciting opportunity to capitalize on the need for extensive, wide field, highly multiplexed, optical/infrared spectroscopy in the coming decade. The Next Generation CFHT concept aims to create a new and expanded CFHT partnership to: 1. replace the present 3.6m primary mirror with a 10m-class (segmented) mirror, mounted on the existing pier. 2. install a dedicated wide-field (1.5 deg 2 ) multi-object spectrograph that can simultaneously collect spectra for >3000 sources. 3. do this by ~2020 and immediately begin spectroscopic surveys. provide the spectroscopic complement to MegaCam, PS1, Skymapper, HyperSuprimeCam, ODI, DES, GAIA, LSST, EUCLID and WFIRST. ngcfht should enable focussed science for key targets and/or programs.

31 Summary D (Mpc ) 5 kpc 10 pc TRGB+2 (I) GCLF mean(g) milestone M31, nearest MW analog NGC 5128 nearest massive E (pec) Virgo Cluster Intergalactic GCs in Coma cluster Coma cluster Nearby galaxies NGVS GCs in Virgo Probing Galactic halo: utility of u-band Resolving stellar systems Telescope Access Program