Padova 033D Spectrography

3D spectrography3D spectrography

V – Density waves in the innerV – Density waves in the inner

regions of galaxies regions of galaxies

Padova 033D Spectrography

DDensity ensity WWaves in aves in galaxiesgalaxies

Spirals

Bars

> 50% of grand-design

> 70% of spirals?

Lindblad, Lin & Shu (60’s)

Warps

Lopsidedness

All disk galaxies?

Very common

(Kamphuis et al. 91)

(Sancisi 76)

Padova 033D Spectrography

Role of Role of DDensity ensity WWavesaves

Torques Local density enhancements crowding,

shocks Angular momentum transfer Dynamical diffusion / heating

– Link with: Secular evolution?

Star formation, starbursts?– AGN?–

NGC 4314

Padova 033D Spectrography

IDWIDW: Towards the centre: Towards the centre Shorter dynamical timescales !! Peaked density distributions (cusps, BHs) A priori lower fraction of dark matter (besides the BH), Axisymmetrisation? Importance of self-gravity

A few numbers:

100 pc 100 pc 10 1066 yrs at 100 km/s yrs at 100 km/s

• Duty cycle of an AGN? 107 – 108

yr

• Average Fueling rate? 0.001 – 1 Msun / yr

• Total mass used? 104-108 Msun

Padova 033D Spectrography

Epicycles and resonancesEpicycles and resonances

Natural frequency of the system: angular frequency

For a disk (potential ):

RR

R

V

VRR

RRR

c

c

2c

z

V

Ω

L

2

0 0et0th Ordre

Padova 033D Spectrography

Natural frequencies of the system:: circular frequency : radial epicyclic frequency

Epicycles and resonancesEpicycles and resonances

zzz

RRR

0

0

0

zz

Rt

RRR

02

2

0th Order

00

2

000

2

2

cos

03

00

tttRR

RR

RRRR

RzRR

zRR

For a disk (potential ):

Padova 033D Spectrography

Rotating with an angular velocity

Epicycles and resonancesEpicycles and resonances

0

2

22

22

2

0

4

4

zRRz

ABBR

R

Natural frequencies of the system:: circular frequency : radial epicyclic frequency

For a disk (potential ):

Padova 033D Spectrography

Epicycles and resonancesEpicycles and resonances

2:rotation Rigid

2:rotationFlat

:Keplerian

Natural frequencies of the system:: circular frequency : radial epicyclic frequency

For a disk (potential ):

Padova 033D Spectrography

PrecessionPrecession

● Precession of elliptical orbits: / 2

Alignement Non Alignement

Structure with rigid rotation p if:

p / 2 = CTE

Padova 033D Spectrography

Propagation, amplificationPropagation, amplification

CR

ILR

If Q > 1: evanescent waves

Potential is a superposition of spiral perturbations

j

jjjj RfmtitR exp,,

Padova 033D Spectrography

Bars and angular Bars and angular momentummomentum

● Gas outside the CR

● Gas between the CR and l’ILR

OLR

ILR

Change of orientation of the orbits at the resonances :

gradual change for the gas

Padova 033D Spectrography

NGC 1068NGC 1068

Lai (CFHT, I + K + Br

N E

Padova 033D Spectrography

NGC 1068 with SAURONNGC 1068 with SAURON

NE

Coll.: K. Fathi, H. Wozniak, P. Ferruit, R. Peletier & the SAURON team

Padova 033D Spectrography

Modelling NGC 1068Modelling NGC 1068

• Mass model: NIR Photometry and Velocity curve• Stars and gas: ‘’Ringberg standards’’

Coll.: K. Fathi, H. Wozniak, P. Ferruit, R. Peletier & the SAURON team

Padova 033D Spectrography

Gas…Gas…

N E

Coll.: K. Fathi, H. Wozniak, P. Ferruit, R. Peletier & the SAURON team

Model

SAURON

Padova 033D Spectrography

SAURON

Model

And stars…And stars…

N E

Coll.: K. Fathi, H. Wozniak, P. Ferruit, R. Peletier & the SAURON team

Padova 033D Spectrography

IDWIDW: Inner bars versus AGN?: Inner bars versus AGN?

The DEBCA project

NGC 1808(starburst)

H band

Emsellem, Greusard, Combes et al. 01, A&A 368, 52

ISAAC / VLTCO bandhead (2.3 m)

SDD

major minor

Padova 033D Spectrography

NGC 3623 (Sa)

Gnd based Image 7' x 7' Stars

SAURON / WHT

SStellartellar DDispersion ispersion DDroprops in 2Ds in 2D

Padova 033D Spectrography

Nuclear spiralsNuclear spirals

Regan & Mulchaey 99, AJ 117, 2676 (HST, WFPC2 / NICMOS)

1.6 m100 pc

Padova 033D Spectrography

IDWIDW: Inner spirals: Inner spirals

DSS 4’x4’

NGC 2974

E4 Vs = 1866 km/sD ~ 25 Mpc

Mdust ~ 1.5 106 Msun (IRAS)MHI ~ 8 108 Msun (Kim et al. 1988)MHII ~ 3 104 Msun (Buson et al. 1993)

Emsellem & Goudfrooij 03, MNRAS

Padova 033D Spectrography

NGC 2974

E(V - I)

WFPC2

[NII]+H

240 pcLRF

Emsellem & Goudfrooij 03, MNRAS

IDWIDW: Inner spirals: Inner spirals

Padova 033D Spectrography

And the winner is …And the winner is …

Emsellem & Goudfrooij 03, MNRAS

Padova 033D Spectrography

The inner bar: Integral Field The inner bar: Integral Field datadata

NGC 2974

TIGER – CFHT(3D Deconvolution)

Emsellem & Goudfrooij 03, MNRAS

V

Padova 033D Spectrography

NGC 3504NGC 3504: m=1 : m=1 modesmodes

NGC 3504

Optical

NIR

Combes et al.

PUEO / CFHT

WFPC2 / HST

OASIS / CFHT

I band

Coll.: Didier Greusard, Françoise Combes

arcsec

Padova 033D Spectrography

PUEO/CFHT

WFPC2/HST

K

F606W

OASIS / CFHT

H [NII]

Vgas[OI]

NGC 3504

Coll.: Didier Greusard, Françoise Combes

NGC 3504NGC 3504: m=1 : m=1 modesmodes

Padova 033D Spectrography

Berman 01, A&A 371, 476

gas flow model

Absorption map model

kpc

kpcar

csec

F814W

5 pc

arcsec

HRCAM

IDW: Towards the BH

M 31

STIS

Bulge & Nucleus

UV peak

Bacon, Emsellem, Monnet, et al. 1994, Emsellem & Combes 1997: Mbh = 7 107 Msun

Padova 033D Spectrography

M31 – KepleriM31 – Kepleri an m=1an m=1

I V

OASIS / CFHT

N body simulation

Bacon, Emsellem, Combes, et al. 01, A&A 371, 409

Padova 033D Spectrography

Summary - ConclusionsSummary - Conclusions• Density waves have an important role in redistributing the

dissipative component and reshaping the galaxy (nuclear disks) Resonances!!

• Density waves are present in the central regions of galaxies. nuclear bars versus central starbursts (cold system) nuclear spirals are common but have low amplitudes … nuclear m=1 modes may be common keplerian m=1 (M 31)

• The presence of gas is critical

• 3D spectrography is required (again…)

• Central starburst – AGN: evolution sequence?

• Time-scales! (fueling the nucleus, starburst, AGN, dynamical heating …)