1 / 22

1 – stellar populations of galaxies in high-z groups/clusters

On the formation time scale of massive cluster ellipticals based on deep near-IR spectroscopy at z~2 Masayuki Tanaka (NAOJ) Sune Toft (DARK), Alexis Finoguenov (Helsinki), Mohammad Mirkazemi (MPE), Dave Wilman (MPE), John Mulchaey (Carnegie),

gale
Download Presentation

1 – stellar populations of galaxies in high-z groups/clusters

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. On the formation time scale of massive cluster ellipticals based on deep near-IR spectroscopy at z~2 Masayuki Tanaka (NAOJ) SuneToft (DARK), Alexis Finoguenov (Helsinki), Mohammad Mirkazemi (MPE), Dave Wilman (MPE), John Mulchaey (Carnegie), Ueda Yoshihiro (Kyoto), YongquanXue (Penn State), Niel Brandt (Penn State), DaniloMarchesini (Tufts), Andrew Zirm (DARK), Carlos De Breuck (ESO), Tadayuki Kodama (NAOJ), Yusei Koyama (NAOJ), Jaron Kurk (MPE), Ichi Tanaka (NAOJ)

  2. 1 – stellar populations of galaxies in high-z groups/clusters 2 – formation timescale of massive cluster ellipticals

  3. 1 – A very low-mass group at z=1.61

  4. Psuedo-color image based on ACS/WFC3 images from CANDELS Note that this system is NOT the Kurk+09 system. A group of galaxies at z=1.61 in the Chandra Deep Field South Tanaka et al. 2013 PASJ, 65, 17

  5. Psuedo-color image based on ACS/WFC3 images from CANDELS Note that this system is NOT the Kurk+09 system. M200 ~ 3x10^13 Msun A progenitor of today's cluster of typical mass A group of galaxies at z=1.61 in the Chandra Deep Field South Tanaka et al. 2013 PASJ, 65, 17

  6. Color-magnitude diagram Photo-z member candidates Spectroscopically confirmed fg/bg galaxies. Mags/Colors are from ACS/WFC3 from CANDELS. Tanaka et al. 2013, PASJ, 65 17

  7. Color-magnitude diagram Photo-z member candidates Spectroscopically confirmed fg/bg galaxies. Surprisingly prominent red sequence! Bright members are almost exclusively red. - No MIPS detection of these red galaxies. - Most of these galaxies are early-type galaxies. - AGN fraction~ 40% Mags/Colors are from ACS/WFC3 from CANDELS. Tanaka et al. 2013, PASJ, 65 17

  8. Deep nearIR spectroscopy with MOIRCS Object spectrum Noise spectrum 7 hours integration on one of the brightest members...

  9. Deep nearIR spectroscopy with MOIRCS Object spectrum Noise spectrum 7 hours integration on one of the brightest members... Binnig helps reduce non-Gaussian noise due to sky residuals.

  10. Spectrophotometric fit cD galaxy of the group. Note the large stellar mass. Tanaka et al. in prep.

  11. Spectrophotometric fit Tanaka et al. in prep.

  12. Stellar populations in z~1.5 systems Compared to the field, galaxies in groups and clusters have -- lower SFRs (this work) -- higher SFRs (Tran+ 2010, Joana’s talk) -- similar SFRs (Ziparo+ 2013) There seems to be a large diversity in galaxy populations in high-z systems We should probably move on to do statistical work. How do we get deep data over a large area?

  13. 2 – A forming cluster at z=2.16

  14. Koyama et al. 2013 MNRAS, 428, 1551 PKS1138 at z=2.16 Tanaka, De Breuck, Venemans, Kurk et al. 2010 A&A

  15. Spectrophotometric fits again... We identified 11 proto-cluster members this way. Tanaka et al. 2013 ApJ, 772, 113

  16. Nascent red sequence A bit busy plot, but the colored objects are likely members. Note that the quiescent galaxies lie on the reddest part of the red sequence. Tanaka et al. 2013 ApJ, 772, 113

  17. Stacked spectrum of the 4 quiescent galaxies Atmospheric absorption Best-fit model spectrum shifted downwards for clarity No strong emissoin lines and the galaxies are indeed quiescent. Possible CaIIH+K feature...? Tanaka et al. 2013 ApJ, 772, 113

  18. Affected by systematics in the zero points. Affected by flux calibration uncertainty tv is forced to be 0 Not strongly affected by flux calibration uncertainty Constraints on the formation time scale Free parameters are : (1) formation redshift (or age), (2) extinction, (3) star formation time scale (A) Location of the red sequence on a color-magnitude diagram: z_f ~ 4 (assums tau_v=0 and tau=0) (B) Full spectral fitting: (C) Dn4000 (insensitive to dust): tau <~ 0.5 Gyr

  19. Formationtimescale Recent numerical simulations of early-type galaxy formation by Johansson et al. (2012) suggest the formation timescale of ~1.5Gyr. Missing ingredients in sims? Or, high density environment is important? Of course the number suffers from uncertainty in SPS models. e-folding timescale of ~1.5Gyr.

  20. Hyper Suprime-Cam (HSC) 1.5 deg diameter FoV A 300-night survey with HSC has just started! HSC-Wide: ~26-ish mags in grizy over 1400sqdeg HSC-Deep: ~27-ish mags in grizy plus a few NBs over 28sqdeg HSC-UltraDeep: ~27.5-ish mags in BB and several NBs over 3sqdeg Weak-lensing cosmology, transients, MW and local galaxies, AGNs/QSOs at z>~6, galaxies, clusters, etc, etc. Public data release planned every 1-2 years. So stay tuned!

  21. Survey strategy Filter exp.time 2”mag. lim. g 10 hours 28.1 r 10 hours 27.7 i 20 hours 27.4 z 27 hours 26.8 y 27 hours 26.3 g 2 hours 27.5 r 2 hours 27.1 i 3 hours 26.8 z 3 hours 26.0 y 3 hours 25.3 g 10 min 26.7 r 10 min 26.2 i 20 min 26.0 z 20 min 25.2 y 20 min 24.4 HSC-Ultra Deep 3.5 sq. deg. 10-30 hours in BB+NB HSC-Deep 28 sq. deg. 2-4 hours in BB+NB HSC-Wide 1400 sq. deg. 10-min in BB A weather factor is included in the mag limits for D and UD.

  22. Target fields Wide : Spring/Autumn equatorial region + HectoMAP region Deep : XMM-LSS, E-COSMOS, ELAIS-N1, DEEP2-F3 UDeep : SXDS (XMM-LSS), COSMOS

More Related