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LoОc Le Tiran loic.le-tiran@obspm.fr Spineto June 10th, 2015

Stirring Up the Gas: Star Formation and Powering High Pressures in galaxies 10 Billion Years Ago


An epoch of intense activity
More s tars created

Time Hopkins & Beacom, 2006


Irregular morphologies
(NI CMOS F160W)

· Morphologies are increasingly irregular towards higher redshifts. · The covering fraction of star forming regions appears to be high in intensely star forming galaxies.


Put your glasses on Rose, we're doing

3D spectroscopy!


The sample used for this work

53 galaxies 1 .3 < z < 2 .7

V/

200 kpc 70 M yr 1

2

-1

SFR [M yr-1]


The dispersion of gas in these galaxies is very high.

What is causing all these random motions?


Random motions VS H luminosity



1
galaxy H


Is there a trend between SFR and H velocity dispertion?
More Random Motions

[km s-1]

More Star Formation per unit area

Log SBH [erg s-1 cm-2 kpc-2]
Lehnert et al. (2009)


Is there a trend between SFR and H velocity dispertion?
More Random Motions

=(

SFR

: s caling from local galaxies
More Star Formation per unit area

[km s-1] )

That 's just Ev2

1/2

Log SBH [erg s-1 cm-2 kpc-2]
Lehnert et al. (2009)


So do you think these random motions are produced by the intense star formation?


What else?

Lehnert+2009,2013, Le Tiran+2011ab


Maybe gas accretion produces these random motions?

Let's check!


What quantity of gas do we need to fuel the H luminosities?
Gas accretion rate: in M yr-1 kpc-2: Raymond 1978 Allen 2008

From shock models, we can s how that an unrealis tic gas accretion rate is needed to power the H velocity dis pers ions and luminos ities.

Le Tiran et al. (2011a)


What quantity of gas infall do we need to fuel the H luminosities?

50 000 M



-1 yr

Le Tiran et al. (2011a)


Distinguishing between the different contributions of H luminosity

Time We can model the different contributions from accretion and star formation. Obs erving the effect of gas accretion in H will be difficult.

Le Tiran et al. (2011a)


Maybe the large H linewidths are just an instrumental effect?

Beam smearing? I don't think so. Here's why...


Quantifying the Effects of Beam Smearing
N-body/SPH Simulation
(Di Matte o, Bournaud e t al . 2008)

S FR

V



We can use simulated "clumpy disks" and analog them to a virtual SI NFONI observation, in order to study the importance of beam smearing

H

V
Virtual obs ervation




Quantifying the Effects of Beam Smearing
gravitational dispersion

We can us e s imulated "clumpy disks" and analog them to a virtual SI NFONI obs ervation, in order to s tudy the importance of beam smearing


Quantifying the Effects of Beam Smearing
gravitational dispersion analytic dispersion

=(

SFR

)

1/2

We can us e s imulated "clumpy disks" and analog them to a virtual SI NFONI obs ervation, in order to s tudy the importance of beam smearing


What is stirring up the gas?
Gas accretion An instrumental effect

Star formation

The moon