Presentation is loading. Please wait.

Presentation is loading. Please wait.

Mathieu PUECH GEPI Observatoire de Paris Rebuilding discs with gas-rich major merger ESO 3D2014 – March 2014, R. Delgado, M. Rodrigues, S. Fouquet + J.L.

Similar presentations


Presentation on theme: "Mathieu PUECH GEPI Observatoire de Paris Rebuilding discs with gas-rich major merger ESO 3D2014 – March 2014, R. Delgado, M. Rodrigues, S. Fouquet + J.L."— Presentation transcript:

1 Mathieu PUECH GEPI Observatoire de Paris Rebuilding discs with gas-rich major merger ESO 3D2014 – March 2014, R. Delgado, M. Rodrigues, S. Fouquet + J.L. Wang, L. Athanassoula, P. Hopkins

2 M 31 NGC 2997 M83 M100 SABbc NGC 1365 M stellar > 2x10 10 M o 72% of local galaxies are spiral

3 Intermediate-mass galaxies M stellar > 1.5x10 10 M ʘ Likeliest progenitors of present-day ~M* spirals, six billion years ago Sample selection M J < -20.3 & 0.4 < z < 0.9 4 fields, including the CDFS SF sub-sample EW 0 ([OII])>15 Å 0.4 < z < 0.75 The IMAGES survey 3D Spectroscopy VLT/FLAMES-GIRAFFE (R~10000, 8-24hrs exposure) Imaging ACS images (≥ 3 orbits) Multi-  photometry Spitzer, GALEX, ACS, EIS,etc. Integrated spectroscopy VLT/FORS2 (600RI+600z) (≥ 3 hrs each)

4 Yang+08 LF, z=0.5 Pozzetti+03 Representativity IMAGES = representative sample of 63 M* galaxies selected in 4 different fields of view (unbiased by cosmic variance) LF, z=1.0 z=0.45-0.7 SFR-M * Sequence from Noeske+07;Dutton+10

5 Half of z~0.6 spirals had peculiar morphologies Delgado-Serrano+10

6 Morpho-kinematic classification 50% of intermediate-mass galaxies at z~0.6 are not relaxed morphologically OR kinematically Hammer+09b 80% of RD are Sp 95% of CK are M, or Pec/M-T Neichel+08 86% of PR are M, or Pec/M-T Anomalous kinematics of the ionized gas is linked to anomalous morphological distribution of the stars

7 Associating Morpho-kinematics with physical processes COLD STREAMS CLUMP FRAGMENT. MAJOR MERGERS MINOR MERGERS OUTFLOWS SECULAR EVOLUTION

8 Associating Morpho-kinematics with physical processes COLD STREAMS CLUMP FRAGMENT. MAJOR MERGERS MINOR MERGERS OUTFLOWS SECULAR EVOLUTION 20 % of z~0.6 M* galaxies 10 % of rotators (Puech10)

9 Associating Morpho-kinematics with physical processes COLD STREAMS CLUMP FRAGMENT. MAJOR MERGERS MINOR MERGERS OUTFLOWS SECULAR EVOLUTION 20 % of z~0.6 M* galaxies 10 % of rotators (Puech10) <8 % of z~0.6 M* galaxies (Rodrigues+12)

10 Associating Morpho-kinematics with physical processes COLD STREAMS CLUMP FRAGMENT. MAJOR MERGERS MINOR MERGERS OUTFLOWS SECULAR EVOLUTION 20 % of z~0.6 M* galaxies 10 % of rotators (Puech10) <8 % of z~0.6 M* galaxies (Rodrigues+12) GIRAFFU IFU resolution ~ 7 kpc @ z=0.6 (Puech+07,12)

11 Associating Morpho-kinematics with physical processes COLD STREAMS CLUMP FRAGMENT. MAJOR MERGERS MINOR MERGERS OUTFLOWS SECULAR EVOLUTION 20 % of z~0.6 M* galaxies 10 % of rotators (Puech10) <8 % of z~0.6 M* galaxies (Rodrigues+12) GIRAFFU IFU resolution ~ 7 kpc @ z=0.6 (Puech+07,12) Cold flows ↘ (Keres+09,Nelson+13 ) Kinematic imprint too weak (Hopkins+10;Puech+12)

12 Associating Morpho-kinematics with physical processes COLD STREAMS CLUMP FRAGMENT. MAJOR MERGERS MINOR MERGERS OUTFLOWS SECULAR EVOLUTION 20 % of z~0.6 M* galaxies 10 % of rotators (Puech10) <8 % of z~0.6 M* galaxies (Rodrigues+12) GIRAFFU IFU resolution ~ 7 kpc @ z=0.6 (Puech+07,12) Cold flows ↘ (Keres+09,Nelson+13 ) Kinematic imprint too weak (Hopkins+10;Puech+12) Kinematic imprint too weak (Hopkins+10;Puech+12)

13 Hammer et al. 2009b 18/27 non (or semi-)relaxed galaxies have « secured » merger models (ZENO or GADGET2 codes)

14 When (the best) model matches the observations Peirani et al. 2009 Dating the observation time Beginning of the simulation Time

15 Puech+12 Gas compression phases are well constrained and consistant with expectations

16 Merger rate: observations vs. theory The apparent large occurrence (~33%) of merger features in z~0.6 galaxies is due to the large visibility timescale of the morpho-kinematic observations (~1.8 Gyr in the pre-fusion phase and post-fusion phases). Puech, Hammer, Hopkins et al. (2012) See also Lopez-Sanjuan+13 (MASSIV) Observations (IMAGES) Theory (Hopkins' semi-empirical model)  baryon  0.25 and M baryon =10 10.2 -10 11 M ⊙ Impact of possible systematics from Mstellar measurements on theoretical predictions

17 Hammer et al. 2009b z=0 ; Schiminovich08 z=0 ; GASS survey z=0.6, IMAGES z=2, Erb+06 z=1, Tacconi+10 z=2, Erb+06 z=2, Tacconi+10 z=1.5, Daddi+10 Properties of the IMAGES merger progenitors Reformation of a significant disk expected after such gas-rich major mergers (Hopkins+09-12 ; Keres+12 w/ AREPO) Rodrigues+12

18 Semi-empirical models with gas-rich mergers Rodrigues+12 Gas fraction (%) Lookback time (Gyr) Hopkins et al 2010 IMAGES Hopkins+10 See also cosmological simulations: Keres+12; Guedes+11, Font+11, Brook+11, Aumer+13 and others Hopkins et al. (2009-2011) +

19 Main sequence of SFGs & major mergers 19 Tension between the SFR peak duration and the duty cycle of major mergers (Noeske+07)? 0.3 dex Duty cycle: 0.4-2.5 Gyr (1-2  ) Cox+08 Individual major mergers: Small SFR peak duration

20 Main sequence of SFGs & major mergers 20 Duty cycle is statistical: need to consider the average SFR peak duration in an representative sample! 0.3 dex Duty cycle: 0.4-2.5 Gyr (1-2  ) Cox+08 Average: much larger SFR peak duration

21 Main sequence of SFGs & major mergers 21 No contradiction between duration of the average SFR peak and major merger duty cycle ( Noeske+07) 1.8 Gyr 0.3 dex Duty cycle: 0.4-2.5 Gyr (1-2  )

22 22 SFR fraction associated to mergers ≈ Morphologically-selected mergers Consistent with Robaina+09: 15-21% (see also Jogee+09) ±5%

23 23 SFR fraction associated to mergers SFR enhancement Consistent with Robaina+09: 8±3% (see also Jogee+09)

24 SFR fraction associated to mergers 24 Total SFR fraction associated to major mergers: 53-88%

25 Conclusions  Morpho-kinematic observations are sensitive to all the phases of the major merger process  The observed major (  baryon  0.25) in M stellar =10 10 -10 11 M ⊙ is found to be in very good agreement with theoretical predictions, without any fine-tuning  33 % of all z~0.6 interm.-mass galaxies are on-going major mergers, which show strong kinematic and morphological perturbations. 50 % of local galaxies have undergone a major merger since z=1.5 (see also MASSIV results).  There is no tension between these fractions and the Main Sequence of star- forming galaxies, the fraction of local bulgeless galaxies (B/T < 0.2, Puech+12), or the fraction of LIRGs  Such mergers should on average produce bulge galaxies with a significant disk. Simulated examples: M31 (Hammer+10), NGC5907 (Wang+12).

26 26 Example of NGC 5907 Wang+12 Best models : 1:3 to 1:5 major mergers with f gas =60- 80% in the progenitors IRAC MartinezDelgado+08 Optical vs. IR/Spitzer:

27 Extras

28 Adapted from Contini+11 Observing galaxy evolution +zC-SINF DYNAMO MASSIV

29 ● RD ■ PR ▲ CK 20% 16% 27% 32% 25% 43% HST VF  S/N VF-model  − model +/- (<)12% (upper limit: Kutdemir+08,10) ? ? ● RD ■ PR ▲ CK Flores+06 Puech+06a Yang+07 SampleGal. Population Kinematic Classification FLAMES-GIRAFFE 3D spectroscopy

30 Associating Morpho-kinematics with physical processes CK galaxies: Morpho-kinematic disturbances are global, not local: GIRAFFU IFU resolution ~ 7 kpc @ z=0.6 Puech et al. (2007)

31 Puech (2010) Clumpy galaxies in IMAGES They represent only ~20% of z~0.6, intermediate-mass galaxies @ z>1 (Elmegreen+05)

32 Clumpy galaxies in IMAGES Half of them are rotators (RD or PR) as expected in clumpy galaxies (Bournaud et al. 2007, 2008).

33 Gas is not necessarly shock-heated at the Virial Radius: Binney 1977 Birnboim & Dekel 2003 Keres et al. 2005 Dekel & Birnboim 2006 Dekel et al. 2009 Keres et al. 2009 Spherical cold gas accretion Streams of cold gas entering massive haloes The standard picture of galaxy formation: Recent developments

34 Brooks+09 shocked « Clumpy » Unshocked Cold gas accretion tends to vanish in massive halos at z<1 (<1.5 Mo/yr at z~0.6, see Keres et al. 2009, Brooks et al. 2009): z~0.6 Cold streams at z~0.6 Puech (2010)

35 Global perturbations Hopkins et al. (2010) Merger rate Secular Perturbation/merger Accretion rate Puech, Hammer, Hopkins et al. (2012) Rotators: Time-scale amplification for internal or external global perturbations IMAGES Kinematic perturbations are too strong to be associated to accretion or internal perturbations

36 Associating Morpho-kinematics with physical processes Only a handful of galaxies have significant shifts between abs. and emission lines (Puech10; Rodrigues+12). [NeIII]HeI HH Integrated FORS2 spectroscopy ~162km/s

37 Barden et al. (2009) hardly detectable above z~0.5-1 Absence of tidail tails, shells, etc. is not an evidence of an absence of merger above z~0.5-1 Observing LSB material


Download ppt "Mathieu PUECH GEPI Observatoire de Paris Rebuilding discs with gas-rich major merger ESO 3D2014 – March 2014, R. Delgado, M. Rodrigues, S. Fouquet + J.L."

Similar presentations


Ads by Google