Matthieu Schaller & EAGLE team

ICC, Durham University, UK

Mockgalaxycataloguefromhydrodynamicalsimulations.The

exampleofEAGLE.

Mock Santiago, Santiago, Chile, 19/04/2016

www.eaglesim.org → Public Galaxy Catalogue

Many collaborators

● James Trayford, Peter Camps (SED, images, dust, …)

● Stuart McAlpine, Yan Qu, John Helly (merger trees, database, ...)

EAGLE in a nutshell

Schaye+2015 (1407.7040), Crain+2015 (1501.01311), Schaller+2015 (1509.05056)

EAGLE in a nutshellFree parameters in the model were calibrated to reproduce the z=0 GSMF and relation between galaxy masses and sizes.

EAGLE in a nutshellEvolution comes out nicely and reveals interesting tensions.

EAGLE in a nutshellToo good a fit for current data ?

Furlong+2015

EAGLE in a nutshell

Trayford+2015 (1504.04374)

A note on resolution

A note on resolution

A note on resolution

Hydro for mocks ? Seriously ?

4.5M CPU hours (final run) + 40M hours (calibration) + 2M hours (post-processing)

Reason 1: Baryons-DM interaction

● Halo mass functions change between DMONLY and HYDRO (>10% level) !

● If (big if) one could measure the HMF, and would use DMONLY as reference point, one would infer modified gravity at the many-sigma level !

See also Cusworth+2014 on the same topic.

Reason 1: Baryons-DM interaction

Hellwing, Schaller et al. 2016

Total matter power-spectrum different (between n-body and EAGLE) at >1% level. Not a trivial effect: - not easy to “fit” out of a DMONLY simulation.

Reason 2: Images,dust and SED

Reason 2: Images,dust and SED

Camps et al. (in prep.)

For each star and star-forming region we construct the corresponding SED. We then construct dust maps from the gas distribution an metallicity. Ray tracing is performed with the SKIRT code.

Reason 2: Images,dust and SEDCombine everything to make IFU cubes and hence spatially resolved emission lines.

EAGLE (SQL) Database● www.eaglesim.org

● McAlpine+2016 (1510.01320)

● Mass, SFR, sizes, Metallicities, Luminosity in all GAMA bands, mock gri-images

● >100,000 galaxies at z=0.

● Merger trees based on 29 snapshots.

● More data products to come

Conclusions

● (Obviously) hydro simulations only cover small volumes and are hard.

● But:– Get “correct” interaction between baryons and DM.

– Get morphology information for the galaxies.

– Get images, colours, spectra, cubes including proper geometrical treatment of dust.

● Future: Calibrate SAMs on hydro ?

Some final entertainment