Mock Santiago - astro.puc.cl · Mock Santiago 2016 Preparing for the Next Generation Surveys 18 22...

Abstract Book

Mock SantiagoPreparing for the Next Generation Surveys

Santiago, Chile

18−22 April 2016

http://www2.astro.puc.cl/mocksantiago/ Image credit: Eagle simulations

Mock Santiago 2016 � Preparing for the Next Generation Surveys � 18−22 April � Santiago � Chile

Rationale: The goal of this workshop is to bring together leading researchers in clustering and galaxy formationstudies and key representatives from major future galaxy surveys to promote discussions and collaborations on howto produce realistic and useful mock galaxy catalogues needed to fully exploit the scientific outcome of those surveys.

Scientific Organising Committee

Nelson Padilla (Chair, Universidad Catolica de Chile)

Carlton Baugh (Institute for Computational Cosmology, Durham University)

Peder Norberg (Institute for Computational Cosmology, Durham University)

Sergio Contreras (Universidad Catolica de Chile)

Local Organising Committee

Nelson Padilla (Chair)

Joaquín Armijo

Matías Bravo

Roberto Gonzalez

Esteban Jimenez

Andrea Kulier

Iván Lacerna

Alejandra Muñoz Arancibia

Enrique Paillas

Paulina Troncoso

Madusha Gunawardhana

Host

Centro de Astro-Ingeniería, Universidad Catolica de Chile

Instituto de Astrofísica, Universidad Catolica de Chile

This workshop is sponsored by the Newton-CONICYT fund, by BASAL Centro de Astronomía y Tecnologías AfinesPFB-06, VRI-PUC, and Fondecyt Regular 1150300.

Abstract Book | www2.astro.puc.cl/mocksantiago/ 2



List of Participants

María Celeste Artale (IAFE)Carlton Baugh (ICC)Lucas Bignone (IAFE)Guillermo Blanc (U. de Chile)Matías Bravo (PUC)Yanchuan Cai (University of Edinburgh)Francisco Castander (ICE)Shaun Cole (ICC)Johan Comparat (UAM)Andy Connolly (UW)Sergio Contreras (PUC)Sofia Cora (IALP)Carlos Correa (IATE)Darren Croton (Swinburne)Joe DeRose (Stanford)Mariano Domínguez (IATE)Francisco Förster (University de Chile)Jaime Forero-Romero (Universidad de los Andes)Gaspar Galaz (PUC)Eric Gawiser (Rutgers University)Roberto Gonzalez (PUC)Violeta Gonzalez-Perez (ICG)Gian Luigi Granato (INAF)Shirley Ho (CMU)Esteban Jimenez (PUC)Antonios Katsianis (U. de Chile)Iván Lacerna (PUC)Claudia Lagos (ICRAR)Diego Lambas (IATE)Sebastián López (U. de Chile)Nuala McCullagh (ICC)Julian Mejia-Restrepo (U. de Chile)Andrés Meza (UNAB)Nicolás Meza (PUC)

Ben Moster (Ludwig-Maximilians-University, Mu-nich)

Martín Moyano (UNC)

Tomas Muller (PUC)

Roberto Muñoz (PUC)

Alejandra Muñoz Arancibia (PUC)

David Murphy (Cambridge)

Peder Norberg (ICC)

Álvaro Orsi (CEFCA)

Nelson Padilla (PUC)

Enrique Paillas (PUC)

Dante Paz (IATE)

Susana Pedrosa (IAFE)

Joaquín Prieto (U. de Chile)

Facundo Rodríguez (IATE)

Silvio Rodríguez (IATE)

Yetli Rosas-Guevara (U. de Chile)

Andrés Ruiz (IATE)

Salvador Salazar (MPE)

Ariel Sanchez (MPE)

Matthieu Schaller (ICC)

Claudia Scoccola (IAFE)

Mario Sgro (IAFE)

Adam Stevens (Swinburne)

Jeremy Tinker (NYU)

Patricia Tissera (UNAB)

Ezequiel Treister (PUC)

Paulina Troncoso (PUC)

Cristian Vega (IALP)

Carolina Villalón (IATE)

Idit Zehavi (Case Western Reserve University)

Zheng Zheng (University of Utah)

Zhenya Zheng (PUC)



Scientific Programme

Monday 18 April

Session-I: SurveysTime: 9:30am − 11:10am Chair: Name Please

Time Speaker Title Abstract

09:30 − 10:10 Shaun Cole The rise of galaxy surveys and mocks (with DESI progress and

challenges)

p.11

10:10 − 10:30 Álvaro Orsi The J-PAS Survey: Probing the Universe in 59 colours p.11

10:30 − 10:50 Zhenya Zheng Ly-Alpha Galaxies at the End of Reionization, the LAGER project p.11

10:50 − 11:10 Peder Norberg WAVES and MOONS: the next large and faint spectroscopic

surveys

p.12

11:10 − 11:40 Coffee Break

Session-II: StatisticsTime: 11:40am − 13:20pm Chair: Name Please

11:40 − 12:20 Ariel Sanchez Cosmological implications of anisotropic clustering measurements

in the final BOSS

p.12

12:20 − 12:40 Silvio

Rodríguez

The real shape of galaxies: Intrinsic and environmental factors p.12

12:40 − 13:00 Andrés Ruiz Calibration of Semi-Analytical Models using Particle Swarm

Optimization

p.13

13:00 − 13:20 Enrique

Paillas

Baryon effects on void statistics p.13

13:20 − 14:50 Lunch at Clementina

Session-III: Mocks with SAMs and HODTime: 14:50pm − 16:30pm Chair: Name Please

14:50 − 15:30 Zheng Zheng Redshift-Space Galaxy Clustering: Accurate Mocks from

Accurate Modeling

p.13

15:30 − 15:50 Idit Zehavi The evolving relation between galaxies and dark matter halos p.14



15:50 − 16:10 Claudia

Scoccola

MultiDark PATCHY Mocks p.14

16:10 − 16:30 Nuala

McCullagh

Testing the assumptions of SHAM and HOD models with Galform p.14


Session-IV: DiscussionsTime: 17:00pm − 18:00pm Led by: Andy Connolly , Shaun Cole and Idit Zehavi



Tuesday 19 April

Session-I: Why SAMs or Hydro?Time: 9:30am − 12:20pm Chair: Name Please


09:30 − 10:10 Claudia Lagos A discussion on semi-analytic models and hydro-simulations:

which one, when and why

p.14

10:10 − 10:30 María Celeste

Artale

Galaxy clustering in EAGLE compared to GAMA and Illustris p.15

10:30 − 10:50 Violeta

Gonzalez-

Perez

Eagle, L-Galaxies and Galform p.15

10:50 − 11:10 Matthieu

Schaller

Mock galaxy catalogue from hydrodynamical simulations. The

example of EAGLE

p.15


11:40 − 12:00 Patricia

Tissera

Chemical Abundances of gas and stars in discs using

hydrodynamical simulations

p.16

12:00 − 12:20 Adam Stevens Angular-momentum evolution of galaxies from semi-analytics p.16

12:20 − 12:40 Alejandra

Muñoz

Arancibia

Modeling complex emission processes in galaxy populations

through the Proxy+Matching technique

p.16

12:40 − 13:00 Nelson Padilla Nifty comparison of semi-analytic and HOD galaxy models p.17

13:00 − 13:20 Sergio

Contreras

The galaxy - dark matter halo connection p.17

13:20 − 14:50 Lunch

Session-II: SurveysTime: 14:50pm − 16:30pm Chair: Name Please

14:50 − 15:10 Shirley Ho How we learn to love the BOSS and planning for the future p.18

15:10 − 15:30 David

Murphy

Where’s our Southern Sloan? Future prospects for spectrally

mapping the southern sky

p.18



15:30 − 15:50 Guillermo

Blanc

The Hobby Eberly Telescope Dark Energy Experiment

(HETDEX) Pilot Survey: Using LAEs for Cosmology

p.18

15:50 − 16:10 Francisco

Castander

The MICE simulations mock catalogues p.19

16:10 − 16:30 Eric Gawiser Optimizing Survey Design for Galaxy Clustering with HETDEX

and LSST

p.19


Session-III: DiscussionsTime: 17:00pm − 18:00pm Led by: Carlton Baugh, Shirley Ho and Eric Gawiser

20:00 − 23:00 Workshop Dinner



Wednesday 20 April

Session-I: SurveysTime: 9:30am − 10:50pm Chair: Name Please


09:50 − 10:10 Paulina

Troncoso

The evolution of Balmer jump selected galaxies in the

ALHAMBRA survey

p.19

10:10 − 10:30 Johan

Comparat

Clustering properties of g-selected galaxies at z=0.8 p.20

10:30 − 10:50 Andy

Connolly

From cosmology to pixels: an end-to-end framework for

simulating data from the LSST

p.20

10:50 − 11:10 Roberto

Muñoz

Chasing ghost galaxies in the Fornax galaxy cluster p.21


Session-II: Why SAMs or Hydro?Time: 10:50am − 13:20pm Chair: Name Please

11:40 − 12:00 Sofia Cora Semi-analytic model SAG p.21

12:00 − 12:20 Carlton

Baugh

Semi-analytical modelling of galaxy formation p.21

12:20 − 12:40 Susana

Pedrosa

Morphological evolution and angular momentum content for

galaxies in a Λ-CDM scenario

p.22

12:40 − 13:00 Darren Croton The TAO of SAGE and the challenge of building a virtual

observatory

p.22

Session-III: StatisticsTime: 14:50am − 15:10pm Chair: Name Please

13:00 − 13:20 Yanchuan Cai Simulating the Gravitational Redshift from Stacked Clusters p.22

13:20 − 14:50 Lunch



14:50 − 15:10 Dante Paz New tools for improving the precision of measurements on the

next-generation of LSS experiments

p.23

15:10 − 15:30 Iván Lacerna Assembly bias in galaxies p.23

15:30 − 15:50 Salvador

Salazar

Clustering tomography on the final SDSS-III BOSS galaxy sample p.23

15:50 − 16:10 Roberto

Gonzalez

Local Group Analogues p.24

16:10 − 16:30 Gaspar Galaz Re-discovering giant low surface brightness galaxies through

simulations: a pending issue

p.24


Session-IV: Poster PresentationsTime: 17:00pm − 18:00pm Chair: Name Please

Lucas Bignone Non-parametric morphological merger indicators in the Illustris

simulation

p.27

Mario Sgro Anisotropic Halo Model p.27

Joaquín Prieto The origin of spin in galaxies: clues from simulations of atomic cooling

haloes

p.27

Matías Bravo − p.28

Antonios Katsianis The simulated SFR-M∗ relation in hydrodynamic simulations p.28

Esteban Jimenez − p.29

Yetli Rosas-Guevara Black hole Evolution in the EAGLE Universe p.29

Facundo Rodríguez Determination of halo occupation distribution: Comparison between

mock and observational catalogues

p.29

Carlos Correa Feasibility study of the Alcock-Paczynski cosmological test using

cosmic voids

p.29

Álvaro Orsi Probing the growth of structure with different galaxy selections and

redshift uncertainties

p.30

C. Villalón Satellite Accretion in a ΛCDM Universe p.30

Martín de los Rios The Messi (Merging Systems Identification) Algorithm p.31



Thursday 21 April

Session-I: Mocks with SAMs and HODTime: 9:30am − 12:00pm Chair: Name Please


09:30 − 09:50 Jeremy Tinker Making Mocks with the Quick Particle Mesh Method p.24

09:50 − 10:10 Mariano

Domínguez

QSOs mocks catalogues and LSS p.25

10:10 − 10:30 Ben Moster Galaxy Assembly in Dark Matter Haloes p.25

10:30 − 10:50 Joe DeRose Mocks for the Dark Energy Survey and Beyond p.25

10:50 − 11:10 Cristian Vega Semi-Analytic Galaxies from the MassiveBlack II simulation p.26


Session-II: DiscussionsTime: 12:00pm − 13:00pm Led by: Patricia Tissera, Claudia Lagos and Ariel Sanchez

Concluding RemarksTime: 12:00pm − 13:00pm By: Diego Lambas

13:20 − 14:50 Lunch

Hands onWorkshopsTime: 14:50pm − 18:00pm

14:50 − 16:30 Sergio Contreras MySQL databases


16:30 − 18:00 F. Förster LSST MAF



Talk Abstracts

Monday

09:30 − 10:10The rise of galaxy surveys and mocks (with DESI progress and challenges)

Shaun Cole (ICC, University of Durham)

I will report on what is required for some aspects of the DESI surveys, the progress we have made and someof the challenges that remain.

Monday

10:10 − 10:30The J-PAS Survey: Probing the Universe in 59 colours


Typical models of anisotropic clustering have achieved only partial agreement against N-body simulationsand standard HOD prescriptions. As a result, clustering data used to constrain cosmological parameters isrestricted to a limited range of scales. Here we explore the performance of such models when confrontedagainst galaxies from a semi-analytical model run over a very large N-body simulation. We focus ongalaxies selected by stellar mass and star-formation rate. The minimum scale that models can reproducewithin a few percent depends on the target selection and the number density of the samples. Furthermore,we explore how models perform when the input real-space clustering (measured from the simulation) isused instead of a linear theory approximations. Implications for future surveys are discussed.

Monday

10:30 − 10:50Ly-Alpha Galaxies at the End of Reionization, the LAGER project

Zhenya Zheng (PUC)

High redshift Lyman-alpha galaxies (LAEs) probe the cosmic re-ionization, as the increasing IGM neutralhydrogen fraction can heavily attenuate the Lya photons, leading to apparent decline in the Lya luminosityfunction. Such declination likely happens at z ∼ 7 according to recent observations, implying a rapid re-ionization. However, due to the limited survey area, very few LAEs have been confirmed at z & 7. Thesuperb large field of view and the high throughput at red wavelengths of DECam make it a unique and oneof the most powerful instruments to the search for large sample of LAEs at z ∼ 7.0. A dedicated narrowbandfilter at 9640A is being built, and we aim to detect several hundred of z ∼ 7.0 LAEs with a deep and largearea DECam narrowband survey. In this talk we introduce our DECam NB964 survey (The Lyman-AlphaGalaxies at the End of Reionization, LAGER) , make comparison with current z & 7 narrowband surveys,and present how it will constrain the ionization fraction of our universe at z = 7 (with Lya luminosityfunction, LAE clustering, as well as the Lya line profile in the follow-up spectroscopic work).

Our survey may also be effective to find high-z quasars, Lyman break galaxies and low-z emissionline galaxies (e.g., Ha emitters at z ∼ 0.5, O iii emitters at z ∼ 0.9, and O ii emitters at z ∼ 1.5), which willhelp to determine the faint end (for ELG) and bright end (for LBG and quasar) of their luminosity function.



Monday

10:50 − 11:10WAVES and MOONS: the next large and faint spectroscopic surveys

Peder Norberg (ICC, University of Durham)

No Abstract

Monday

11:40 − 12:20Cosmological implications of anisotropic clustering measurements in the

final BOSS

Ariel Sanchez (Max Planck Institute for Extraterrestrial Physics)

Thanks to the combined information of BAO and RSD, anisotropic clustering measurements can probesimultaneously the expansion history of the Universe and the growth of density fluctuations, offering in thisway one of the most promising routes to constrain the dark energy equation of state parameter, wDE, andits possible evolution with time, or to detect possible deviations from the predictions of general relativity.The potential of LSS observations as cosmological probes has led to the construction of increasingly largergalaxy catalogues, such as the completed Baryon Oscillation Spectroscopic Survey (BOSS). In this talk,I will review some of the cosmological implications of anisotropic clustering measurements in the finalBOSS.

Monday

12:20 − 12:40The real shape of galaxies: Intrinsic and environmental factors

Silvio Rodríguez (IATE - OAC, Cordoba)

By modelling the axis ratio distribution of SDSS DR8 galaxies we find the intrinsic 3D shapes of spirals andellipticals. We use morphological information from the Galaxy Zoo project and assume a non-parametricdistribution intrinsic of shapes, while taking into account dust extinction.

We find that the intrinsic shapes of galaxies and their dust extinction vary with absolute magnitude,colour and physical size. We find that bright elliptical galaxies are more spherical than faint ones, a trendthat is also present with galaxy size, and that there is no dependence of elliptical galaxy shape with colour.For spiral galaxies we find that the thickness of discs increases with luminosity and size, and that brighter,smaller and redder galaxies have less round discs.

We also measure the effect of the environment on the intrinsic shapes of galaxies. We find thatspiral galaxies in groups are very similar to field spirals with similar intrinsic properties (magnitudes, sizesand colours). But for spirals in groups, those in denser environments or closer to the centre of the grouptend to have a more circular disc than similar galaxies in less dense environments or far from the group

centres. Also we find that central spiral galaxies in their groups tend to be thinner than other similar spirals.For ellipticals, we do not find any important dependence of their shape on their position in a group or onthe local density. However, we find that elliptical galaxies in groups tend to be more spherical than fieldellipticals with similar intrinsic properties.



Monday

12:40 − 13:00Calibration of Semi-Analytical Models using Particle Swarm Optimization

Andrés Ruiz (IATE - OAC)

In this talk I briefly present a fast and accurate method to select an optimal set of parameters in semi-analyticmodels of galaxy formation. Our approach compares the results of a model against a set of observablesapplying a stochastic technique called Particle Swarm Optimization (PSO), a self-learning algorithm forlocalizing regions of maximum likelihood in multidimensional spaces that outperforms traditional samplingmethods in terms of computational cost.

Monday

13:00 − 13:20Baryon effects on void statistics

Enrique Paillas (PUC)

EAGLE provides a unique opportunity to test the effects of baryons on the statistics of voids. Several workshave studied the abundance of voids in numerical simulations (e.g. Cai, Padilla & Li 2014), with the aimof using these statistics to tell apart different cosmological models. However, in these simulations only theevolution of the dark matter (DM) is followed. At best, DM haloes are used to trace the density field in anattempt to simulate what happens when galaxies are used to identify voids in real catalogues. With EAGLEwe can quantify the effects from baryons. These range from the change in the DM halo mass function dueto feedback, the multiple galaxies that inhabit each halo, and the effect of feedback on other scales. Forinstance, it is possible that the walls and filaments that constitute the void boundaries are different whenbaryons are present. We will use the DM-only and full EAGLE simulations to test these effects, primarilyon the abundance of voids, but also on their density and dynamics profiles.

Monday

14:50 − 15:30Redshift-Space Galaxy Clustering: Accurate Mocks from Accurate

Modelling

Zheng Zheng (University of Utah)

With the increasing precision of galaxy clustering measurements from ongoing and forthcoming largegalaxy surveys, accurate models are required to interpret the redshift-space data, to extract relevant in-formation, and to produce reliable mock catalogs. I will first present a method based on halos identifiedin high-resolution N-body simulations to accurately and efficiently model the projected and redshift-spacegalaxy two-point correlation functions, which enables an efficient exploration of the parameter space. I thentalk about the applications of such a method to model the small-to-intermediate scale redshift-space clus-

tering of SDSS and BOSS galaxies and discuss the inferred galaxy-halo relation and galaxy velocity bias.Finally, I will comment on constructing redshift-space mock galaxy catalogs from the modelling results.



Monday

15:30 − 15:50The evolving relation between galaxies and dark matter halos

Idit Zehavi (Case Western Reserve University)

The Halo Occupation Distribution (HOD) approach is a powerful tool for interpreting galaxy clusteringmeasurements and constraining the galaxy-halo connection. We present new results for the redshift evo-lution of the HOD predicted by semi-analytic galaxy formation models. This allows to extend the HODapproach and facilitates the creation of realistic mock galaxy catalogs for upcoming surveys.

Monday

15:50 − 16:10MultiDark PATCHY Mocks

Claudia Scoccola (FCAG-UNLP)

No Abstract

Monday

16:10 − 16:30Testing the assumptions of SHAM and HOD models with Galform

Nuala McCullagh (ICC, University of Durham)

I will discuss current work on using the Galform P-Millennium galaxy catalogue to test the assumptionsmade in subhalo abundance matching (SHAM) and halo occupation distribution (HOD) models. Whilethe clustering in the Galform catalogue matches the observed clustering in SDSS, the form of the halooccupation distributions are quite different from both the HODs resulting from SHAM and the standardHOD models assumed in the literature. This allows us to test the assumption of standard HODs and toexplore our sensitivity to different HOD forms.

Tuesday

09:30 − 10:10A discussion on semi-analytic models and hydro-simulations: which one,

when and why

Claudia Lagos (ICRAR)

Semi-analytic models and hydrodynamical simulations are two widely used tools to study the connectionbetween the growth of structures in the Universe and how this drives the formation and evolution of galaxies.Both tools have valuable characteristics that can be very useful in different circumstances, but to be able tomaximise the science coming out of both tools is critical to understand their advantages and limitations andwhich type of surveys would mostly benefit of each of these tools. During this talk I will discuss when and

why semi-analytic models are preferred over hydro-simulations and vice-versa.



Tuesday

10:10 − 10:30Galaxy clustering in EAGLE compared to GAMA and Illustris

María Celeste Artale (Instituto de Astronomía y Física del Espacio)

We measure the projected galaxy correlation function from the cosmological hydrodynamical simulationEAGLE. We compare the clustering of samples split by luminosity, stellar mass and star formation rate withresults from the GAMA survey, with two semi-analytic galaxy formation models and with the hydrodynam-ical cosmological simulation Illustris. Our findings indicate that the galaxy clustering in EAGLE presentsa good level of agreement with GAMA and that differences in the clustering between EAGLE, Illustris andthe semi-analytic models provide key insight on the different galaxy formation physics implemented in themodels.

Tuesday

10:30 − 10:50Eagle, L-Galaxies and Galform

Violeta Gonzalez-Perez (ICG, University of Portsmouth)

No Abstract

Tuesday

10:50 − 11:10Mock galaxy catalogue from hydrodynamical simulations. The example of

EAGLE

Matthieu Schaller (ICC, University of Durham)

In this talk, I’ll present the current and future content of the public database constructed from the galaxycatalogues from the EAGLE hydrodynamical simulations. Hydrodynamical simulations are run on muchsmaller volumes than what is doable with Semi-Analytic models. However, the more complex modellinginvolved allows to include the back-reaction of baryons onto the dark matter, which plays an important rolefor precision cosmology probes. Another benefit over Semi-Analytic Models is the possibility to generatemock images in multiple bands, mock IFU cubes or extract morphological information from the galaxies.

I’ll argue that information from hydrodynamical simulations combined with SAMs should be atthe heart of future mock catalogue efforts.



Tuesday

11:40 − 12:00Chemical Abundances of gas and stars in discs using hydrodynamical

simulations

Patricia Tissera (UNAB)

No Abstract

Tuesday

12:00 − 12:20Angular-momentum evolution of galaxies from semi-analytics

Adam Stevens (UNAB)

Using "Dark SAGE", a new semi-analytic model with consideration of resolved disc structure, I will presentthe evolution of the mass–specific angular momentum relation of galactic discs. This sequence has strongties to Toomre disc instabilities, which I will show are mandatory for regulating the mass–spin sequence.Our method of discretising discs in annuli of fixed specific angular momentum leads to the natural formationof pseudobulges in most spiral galaxies. With a simple disc–pseudobulge decomposition, we find our modelpredicts the mass and spin of galaxies to be tightly correlated, in remarkable agreement with observations.

Tuesday

12:20 − 12:40Modeling complex emission processes in galaxy populations through the

Proxy+Matching technique

Alejandra Muñoz Arancibia (IFA-UV)

We introduce a novel technique for modeling luminosities at different wavelengths in large samples ofgalaxies, suitable for emission processes whose complexity requires many untested assumptions or the useof sophisticated algorithms: in the "Proxy+Matching" approach, a physical galaxy property from the modelis chosen as a proxy for another property whose numerical value is unknown. Both proxy and unknownare assumed to follow a monotonic relationship, assigning that unknown to the simulated galaxies in sucha way that some observational statistics for it are reproduced. By comparing the predictions for furthergalaxy properties with observations, a good proxy can be found. We present the prospects of this techniquefor probing the submillimeter and Lyman alpha emission from galaxies in a cosmological framework, usinga semi-analytic model of galaxy formation and evolution.



Tuesday

12:40 − 13:00Nifty comparison of semi-analytic and HOD galaxy models

Nelson Padilla (Swinburne University of Technology)

The nifty project compares the output of 12 semi-analytic and 2 halo occupation distribution models, allof which use the same parent simulation. Results of this comparison on the abundance of galaxies as afunction of their intrinsic properties, and their clustering will be shown.

Tuesday

13:00 − 13:20The galaxy - dark matter halo connection

Sergio Contreras (PUC)

We demonstrate how the properties of a galaxy depend on the mass of its host dark matter subhalo, usingtwo independent models of galaxy formation. For the cases of stellar mass and black hole mass, the medianproperty value displays a monotonic dependence on subhalo mass. The slope of the relation changes forsubhalo masses for which heating by active galactic nuclei becomes important. The median property valuesare predicted to be remarkably similar for central and satellite galaxies. The two models predict considerablescatter around the median property value, though the size of the scatter is model dependent. There isonly modest evolution with redshift in the median galaxy property at a fixed subhalo mass. Propertiessuch as cold gas mass and star formation rate, however, are predicted to have a complex dependence onsubhalo mass. In these cases subhalo mass is not a good indicator of the value of the galaxy property. Weillustrate how the predictions in the galaxy property - subhalo mass plane differ from the assumptions madein some empirical models of galaxy clustering by reconstructing the model output using a basic subhaloabundance matching scheme. In its simplest form, abundance matching generally does not reproduce theclustering predicted by the models, typically resulting in an overprediction of the clustering signal. Usingthe predictions of the galaxy formation model for the correlations between pairs of galaxy properties, thebasic abundance matching scheme can be extended to reproduce the model predictions more faithfully fora wider range of galaxy properties. Our results have implications for the analysis of galaxy clustering,particularly for low abundance samples.



Tuesday

14:50 − 15:10How we learn to love the BOSS and planning for the future

Shirley Ho (Carnegie Mellon University)

No Abstract

Tuesday

15:10 − 15:30Where’s our Southern Sloan? Future prospects for spectrally mapping the

southern sky

David Murphy (Cambridge University)

Efforts to fully explore the southern hemisphere have gained traction, with large photometric campaigns(e.g. VST-ATLAS, DES, VHS) covering vast regions with multi-band photometry spanning from 350nm to2000nm. Nevertheless, one of the core legacy products driving Northern SDSS science is access to spectraalongside these photometric resources. I highlight the current situation in Chile for spectroscopic supportof the above southern surveys, and what the future holds, particularly for LSST-era science.

Tuesday

15:30 − 15:50The Hobby Eberly Telescope Dark Energy Experiment (HETDEX) Pilot

Survey: Using LAEs for Cosmology

Guillermo Blanc (University de Chile)

I will present the HETDEX Survey, an ambitious project that aims to obtain blind integral field spectroscopyover hundreds of square degrees in order to assemble a sample of 1 million Ly-alpha emitting galaxies at1.8<z<3.5. The main goal of HETDEX is to measure the galaxy distribution power spectrum in orderto study the evolution of the Dark Energy equation of state out to high redshift. Beyond the study ofcosmology the "blind" nature of HETDEX will translate into a massive and diverse spectroscopic datasetthat will include large numbers high redshift and local galaxies, AGNs, MW stars, planetary nebulae aroundnearby galaxies, and any other source falling on the survey footprint. Therefore HETDEX will provide arich database for all kinds of studies in astrophysics. I will describe the survey strategy, present the VIRUSspectrograph which is currently being commissioned at the HET 9.2m telescope, and discuss early resultsfrom the HETDEX Pilot Survey



Tuesday

15:50 − 16:10The MICE simulations mock catalogues

Francisco Castander (ICE, IEEC-CSIC)

I will present the MICE cosmological simulations and associated mock galaxy catalogues (http://cosmohub.pic.es) that have been developed to help design and analyse current and future cosmological surveys. Inparticular, they contain lensing and clustering observables computed in a self-consistent way in a cosmo-logical relevant volume. I will present how they are being used to analyse the first LSS results coming fromthe DES and being optimized to interpret future surveys like PAU, DESI and Euclid.

Tuesday

16:10 − 16:30Optimizing Survey Design for Galaxy Clustering with HETDEX and LSST

Eric Gawiser (Rutgers University)

To take full advantage of the statistics offered by huge galaxy samples, large-scale structure studies withcurrent and future surveys require improved methods for reducing systematic errors. I will give examples oftwo approaches that are relevant to the construction of mock galaxy catalogs: 1. Choosing an LSST ditherpattern that minimizes spurious galaxy clustering caused by non-uniformity in survey depth. 2. ApplyingBayesian and Machine Learning techniques to HETDEX classification of emission line galaxies in redshiftspace.

Wednesday

09:50 − 10:10The evolution of Balmer jump selected galaxies in the ALHAMBRA survey

Paulina Troncoso (PUC)

In this talk, I present a new color-selection technique, based on the Bruzual & Charlot (2003) modelsconvolved with the ALHAMBRA bands. We use the homogeneous optical coverage of the ALHAMBRAfilter system to select samples of star-forming galaxies at different epochs of the Universe and study theirproperties. The redshifted position of the Balmer jump in the optical bands is used to select star-forminggalaxies in the redshift range 0.5 < z < 1.5, those are dubbed Balmer jump Galaxies (BJGs). Five volume-limited BJG sub-samples with different mean redshifts are found to reside in haloes of median masses∼ 1012.5±0.2 Mo slightly increasing toward z = 0.5. This increment is similar to numerical simulationsresults which suggests that we are tracing the evolution of an evolving population of haloes as they grow toreach a mass of ∼ 1012.7±0.1M� at z = 0.5. The likely progenitors of our samples at z ∼ 3 are Lyman BreakGalaxies, which at z ∼ 2 would evolve into star forming BzK galaxies, and their descendants in the localUniverse are elliptical galaxies. Hence, this allows us to follow the putative evolution of the SFR, stellarmass and age of these galaxies. From z = 1.0 to z = 0.5, the stellar mass of the volume limited BJG samplesnearly does not change with redshift, suggesting that major mergers play a minor role on the evolution ofthese galaxies. The SFR evolution accounts for the small variations of stellar mass, suggesting that star

formation and possible minor mergers are the main channels of mass assembly.



Wednesday

10:10 − 10:30Clustering properties of g-selected galaxies at z = 0.8

Johan Comparat (IFT/CSIC UAM Madrid Spain)

Current and future large redshift surveys, as the Sloan Digital Sky Survey IV extended Baryon Oscilla-tion Spectroscopic Survey (SDSS-IV/eBOSS) or the Dark Energy Spectroscopic Instrument (DESI), willuse Emission-Line Galaxies (ELG) to probe cosmological models by mapping the large-scale structure ofthe Universe in the redshift range 0.6 < z < 1.7. With current data, we explore the halo-galaxy connec-tion by measuring three clustering properties of g-selected ELGs as matter tracers in the redshift range0.6 < z < 1: (i) the redshift-space two-point correlation function using spectroscopic redshifts from theBOSS ELG sample and VIPERS; (ii) the angular two-point correlation function on the footprint of theCFHT-LS; (iii) the galaxy-galaxy lensing signal around the ELGs using the CFHTLenS. We interpret theseobservations by mapping them onto the latest high-resolution MultiDark Planck N-body simulation, usinga novel (Sub)Halo-Abundance Matching technique that accounts for the ELG incompleteness. ELGs atz∼ 0.8 live in halos of (1± 0.5)×1012h−1 M� and 22.5±2.5% of them are satellites belonging to a largerhalo. The halo occupation distribution of ELGs indicates that we are sampling the galaxies in which starsform in the most efficient way, according to their stellar-to-halo mass ratio.

Wednesday

10:30 − 10:50From cosmology to pixels: an end-to-end framework for simulating data

from the LSST

Andy Connolly (University of Washington)

The LSST will, over a 10-year period, produce a multi-color, multi-epoch survey of more than 18000 squaredegrees of the southern sky. The end product of the LSST will be an archive of images and catalogs fromwhich a wide variety of high-precision statistical studies can be undertaken. To accomplish this, the LSSTproject has developed a multi-facetted suite of modeling and simulation tools for use in developing the sys-tem requirements and architecture, and validating that the system design and the as-delivered componentswill yield data products with the required statistical properties. I will describe the development, validation,and use of the LSST simulation framework, including the generation of simulated catalogs and images fortargeted trade studies, the creation of large-scale simulations that test the procedures for data calibration,and use of end-to-end image simulations to evaluate the performance of the system as a whole. I will alsoshow how new cosmological models can be integrated within this framework to develop a simulated digitalview of the universe.



Wednesday

10:50 − 11:10Chasing ghost galaxies in the Fornax galaxy cluster

Roberto Muñoz (PUC)

The Fornax galaxy cluster is the second richest cluster within 100 million light years from Earth. Because ofits proximity, which ensures optimal spatial resolution in comparison with more distant clusters, Fornax isan excellent laboratory to study the physical properties of galaxies and dense stellar systems, such as glob-ular clusters (GCs) and ultra-compact dwarf galaxies (UCDs). We have embarked on a multi-wavelengthstudy (DECam/ optical, VISTA/ NIR, VIMOS/ spectroscopy) of the Fornax galaxy cluster over the central1.5 Mpc2 central region, which will allows us to image about 10,000 GCs at previously not covered wave-lengths and provide accurate photometric diagnostics for more than 100 massive galaxies down to MV =-12mag.

Wednesday

11:40 − 12:00Semi-analytic model SAG

Sofia Cora (Instituto de Astrofísica de La Plata, Argentina)

Semi-analytic models of galaxy formation and evolution (SAMs) are a powerful method to study how galax-ies form and evolve within individual dark matter halos in a CDM cosmogony provided by N-body simula-tions. SAMs incorporates the physical processes that affect the baryonic component, with the advantage ofreaching a larger dynamic range than fully selfconsistent hydro-simulations at a far smaller computationalcost. We present the state-of-art of the semi-analytic model SAG. This model follows the formation andevolution of galaxies including gas cooling, star formation, SNe explosions and AGN feedback. Bulge for-mation and black hole growth take place through starbursts driven by mergers and disc instabilities. SAGhas a detailed implementation of metal enrichment of stars and interstellar medium which involves yieldsfrom supernovae type II and Ia taking into account the corresponding lifetimes of their progenitors. It alsoconsiders the effect of gradual star formation during starbursts, of accretion with misaligned angular mo-menta on the properties of galactic disks, and of environmental processes such as tidal stripping and rampressure stripping. A special feature of SAG is the possibility of estimating nebular emission of star-forminggalaxies. In this presentation, we show the main achievements of this model, which is able to reproduceobserved properties of both local and high redshift galaxies.

Wednesday

12:00 − 12:20Semi-analytical modelling of galaxy formation

Carlton Baugh (ICC, University of Durham)

I will give an overview of the semi-analytical approach to modelling galaxy formation and explain how itcan be used to build mock catalogues.



Wednesday

12:20 − 12:40Morphological evolution and angular momentum content for galaxies in a

Λ-CDM scenario

Susana Pedrosa (IAFE)

Galaxy formation in the current cosmological paradigm is a very complex process where inflows, outlfows,interactions and mergers are common events. These processes can redistribute the angular momentumcontent of baryons. Recent observational results suggest that disc formed conserving angular momentumwhile elliptical galaxies, albeit losing angular momentum, determine a correlation between the specificangular momentum of the galaxy and the stellar mass. These observations provide stringent constrainfor galaxy formation models in a hierarchical clustering scenario. We use cosmological hydrodynamicalsimulations that include an effective, physically-motivated Supernova feedback to analyse the propertiesand formation history of a sample of galaxies of a cosmological simulation by performing a bulge-discdecomposition of the analysed systems and their progenitor systems.

Wednesday

12:40 − 13:00The TAO of SAGE and the challenge of building a virtual observatory

Darren Croton (Swinburne University of Technology)

In this talk I will discuss the use of new technologies to build and deliver cosmological-scale galaxy for-mation simulations to the astronomy community. Combining high performance computing, a "web 2.0"front-end architecture, and cloud-based processing and storage, the Australian Government funded "The-oretical Astrophysical Observatory" (TAO; https://tao.asvo.org.au) allows astronomers construct their ownmock universes from a range of different simulations, filter the output through virtual telescopes, and down-load the results for their own scientific use. TAO is of value to both large survey teams and individuals, andserves a wide range of scientific needs.

Wednesday

13:00 − 13:20Simulating the Gravitational Redshift from Stacked Clusters

Yanchuan Cai (University of Edinburgh)

Photons from central galaxies sitting at the bottom of the potential well of galaxy clusters are expected to begravitationally shifted by a larger amount than satellites and other neighbouring galaxies. The difference ofthe gravitational redshift signal with respect to the cluster centre is small but can in principle be detected bystacking a large sample of clusters. A robust detection of the gravitational redshift signal using near futuregalaxy redshift surveys may provide a constraint on theories of gravity. This requires an accurate predictionof the observed redshift and a thorough understanding of systematics. Using N-body simulations, I willmake predictions for such a signal and show how it may be affected by systematics such as the assumptionthat individual clusters are spherical symmetric.



Wednesday

14:50 − 15:10New tools for improving the precision of measurements on the

next-generation of LSS experiments

Dante Paz (Instituto de Astronomía Teórica y Experimental - IATE)

The estimation of cosmological constraints from observations of the large-scale structure of the Universe,such as the power spectrum or the correlation function, requires the knowledge of the inverse of the associ-ated covariance matrix, namely the precision matrix, Ψ. In most analysis, Ψ is estimated from a limited setof mock catalogs. Depending on how many mocks are used, this estimation has an associated error whichmust be propagated into the final cosmological constraints. For future surveys such as Euclid and DarkEnergy Spectroscopic Instrument, the control of this additional uncertainty requires a prohibitively largenumber of mock catalogs. In a recent work our group have presented a novel technique for the estimationof the precision matrix, the covariance tapering method, which has a promising future in BAO or CosmicVoids based measurements. In this talk I will review some of these results in the context of the communityefforts for improving the accuracy in the precision cosmology field.

Wednesday

15:10 − 15:30Assembly bias in galaxies

Iván Lacerna (PUC)

In the last decade, results from N-body simulations have shown that the clustering of dark matter haloes atlarge scales depends on the assembly history in addition to the halo mass. This effect in haloes was termed’assembly bias’. By means of semi-analytic models and hydrodynamical simulations of galaxy formation, ithas been found that galaxy clustering on large scales is also affected by the correlation of halo environmentwith halo assembly history. However, on the observational side, the existence of the assembly bias is stilldebated. In this talk, I will present theoretical and observational results related to the assembly bias ingalaxies. This is a relevant issue that could affect the ability of the next generation of galaxy surveys toinfer accurate cosmological parameters.

Wednesday

15:30 − 15:50Clustering tomography on the final SDSS-III BOSS galaxy sample

Salvador Salazar (MPE)

We test the cosmological implications of studying galaxy clustering using a tomographic approach appliedto the final BOSS DR12 galaxy sample, including both auto- and cross-correlation functions between red-shift shells. We model the signal of the full shape of the angular correlation function, ω(θ), in redshift binsusing state-of-the-art modelling of non-linearities, bias and redshift-space distortions. We present resultson the redshift evolution of the linear bias of BOSS galaxies, which cannot be obtained with traditionalmethods for galaxy-clustering analysis. We also obtain constraints on cosmological parameters in severaldifferent parameter-spaces, combining this tomographic analysis with measurements of the CMB and type

Ia supernova (SNIa).



Wednesday

15:50 − 16:10Local Group Analogues

Roberto Gonzalez (PUC)

We can search for MW-M31 like systems(LG analogues) in observational or mock catalogs to study howcommon is the LG in a cosmological context and their properties. I show some results on LG mass, satellitedistribution/accretion history, and the environment where LGs are located.

Wednesday

16:10 − 16:30Re-discovering giant low surface brightness galaxies through simulations: a

pending issue

Gaspar Galaz (PUC)

In this talk we summarize some efforts to reproduce through simulations the appearance of giant low surfacebrightness galaxies (GLSBs) in the universe. In spite of the small number of these kind of galaxies discov-ered so far, very recent discoveries of milky way sized LSB galaxies in the Coma cluster by van Dokkumet al. (2015), and recent deep optical observations of the structure of Malin 1, are boosting the researchon these kind of galaxies. Therefore, it is of great importance to reproduce (e.g. understand) under whichconditions, when in the history of the universe, and where in the cosmic web, these galaxies are formed andhow they evolve. We explore these issues through mock catalogues generated by semi-analytical models.

Thursday

09:30 − 09:50Making Mocks with the Quick Particle Mesh Method

Jeremy Tinker (New York University)

I will demonstrate the power and flexibility of the Quick Particle Mesh technique (QPM) for making realisticmock galaxy catalogs. QPM can create halo catalogs of arbitrarily low halo masses without changing theresolution of the PM simulation on which it is based. Using QPM, we have created mock catalogs withhalos down to 1011 M� in simulation volumes 5 Gpc per side, with minimal computational effort. CurrentQPM mocks can fit the entire DESI survey within them, as well as the eBOSS QSO sample, which extendsfrom z=0.8 to z=2.3.



Thursday

09:50 − 10:10QSOs mocks catalogues and LSS

Mariano Domínguez (IATE)

A high redshift universe QSOs mock is build up based on SAM results on the Millennium simulation and itsresults are compared with an all sky sample of QSO selected from allWISE catalog using machine learningtechniques. We study the QSO halo mass distribution using halo occupation methods and correlations withweak lensing distorsions on the CMB Planck data. Our results show strong evolutive dependences thatshould be taken into account for future mock catalogues and AGN understanding.

Thursday

10:10 − 10:30Galaxy Assembly in Dark Matter Haloes

Ben Moster (Ludwig-Maximilians-University, Munich)

Semi-empirical galaxy formation models (such as abundance matching) provide a unique and direct linkbetween galaxies and dark matter haloes, and do not depend on model assumptions on unresolved physics.I will present the next generation of semi-empirical galaxy formation models that take into account theassembly history of the dark matter haloes. To this end the SFR of a galaxy is computed from the growthrate of a simulated DM halo using a mass and redshift dependent conversion efficiency which is constrainedby requiring several observations (SMFs, sSFRs, clustering, quenched fractions) be reproduced. Whileprevious models determined galaxy quantities only as an average for a given halo mass, the new models canpredict stellar mass, star formation rate, gas mass, and colour for individual systems based on their formationhistory. Using this new technique I will present star formation and accretion histories for quenched and star-forming galaxies, and the evolution of the star formation main sequence. I will also show how other highredshift quantities that will be probed in future surveys can be predicted, such as gas fractions and galaxymerger rates, and how mock observations based on the model look like. Furthermore I will demonstratehow modelled quantities depend on the environment and the galaxy?s location within the cosmic web.

Thursday

10:30 − 10:50Mocks for the Dark Energy Survey and Beyond

Joe DeRose (Stanford University)

The interpretation of the vast amount of data that current and future photometric galaxy surveys collect willrequire the use of mock galaxy catalogs implementing a broad range of physics in many times the volumeof the surveys themselves. I will present new methods that build upon the successes of Subhalo AbundanceMatching while enabling the generation of realistic mocks on the scales necessary for surveys such as theDark Energy Survey.



Thursday

10:50 − 11:10Semi-Analytic Galaxies from the MassiveBlack II simulation

Cristian Vega (Instituto de Astrofísica de La Plata)

The construction of mock galaxy catalogs by applying the semi-analytical model of galaxy formation andevolution SAG in the Dark Matter Only MassiveBlack II simulation is explained here, including details onthe output properties of the galaxies and discussing the advantages of the technique. General benchmarksand the first statistical results of the galaxy population are also shown.



Poster Abstracts

Wednesday

17:00 − 18:00Non-parametric morphological merger indicators in the Illustris simulation

Lucas Bignone (IAFE)

Non-parametric morphological statistics of galaxy images are commonly used to classify galaxy morpholo-gies and to identify mergers signatures. Morphological indicators of merger events are a key part of under-standing the galaxy merger rate, a fundamental yet poorly constraint quantity. Given that merger indicatorsmay be apparent only during a limited time and only under certain conditions, we study the non-parametricmorphological statistics (C, M20 and Gini) of z=0 galaxies in the Illustris simulation and determine thefraction of major merger, minor mergers and close pairs that automatic morphological classification areable to correctly identify, and the timescales during which such identification is possible. The correct un-derstanding of the information provided by automatic classification of mergers events are very importantin light of future large sample surveys such as LSST that will posses the depth, volume, and wavelengthcoverage to greatly improve our knowledge of merger events and rates.

Wednesday

17:00 − 18:00Anisotropic Halo Model

Mario Sgro (IAFE)

We present an extension of the classical halo model which take into account the triaxial shape of the darkmatter halos. It also provides a easy way to quantify the halo-halo alignment.

Wednesday

17:00 − 18:00The origin of spin in galaxies: clues from simulations of atomic cooling

haloes

Joaquín Prieto (Universidad de Chile)

No Abstract



Wednesday

17:00 − 18:00 No Title

Matías Bravo (PUC)

No Abstract

Wednesday

17:00 − 18:00The simulated SFR-M∗ relation in hydrodynamic simulations

Antonios Katsianis (University of Chile)

The relation between the Star Formation Rate (SFR) and stellar mass (M∗) of galaxies represents a funda-mental constraint on galaxy formation, and has been studied extensively both in observations and cosmo-logical hydrodynamic simulations. However, the observed amplitude has not been successfully reproducedin simulations, indicating either that the halo accretion history and baryonic physics are poorly under-stood/modeled or that observations contain biases. In this talk, I present the evolution of the simulated andobserved SFR-M∗ relations of z ∼ 1−4 galaxies. Simulations from various groups (e.g. EAGLES, Illustris,ANGUS) produce relations that have remarkable agreement despite the fact that they have employed differ-ent cosmological codes and run simulations with different resolutions. This is interesting for two reasons.A) simulations can produce realistic populations of galaxies within representative cosmological volumeseven at relatively modest resolutions. B) It is likely that current numerical codes that rely on similar subgridmultiphase Inter-Stellar Medium (ISM) models and are tuned to reproduce statistical properties of galaxies,produce similar results for the SFR-M∗ relation by construction, regardless of resolution, box size and, tosome extent, the adopted feedback prescriptions. In addition, I display the inconsistency between observedrelations that are obtained using different techniques. Numerical results are consistent with observationsthat use Spectral Energy Distribution (SED) techniques to estimate star formation rates, dust correctionsand stellar masses. On the contrary, simulations are not able to reproduce results that were obtained bycombining only UV and IR luminosities (UV+IR). These imply SFRs at a fixed stellar mass that are largeralmost by a factor of 5 than those of SED measurements for z ∼ 1.5− 4. For z < 1.5, the results fromsimulations, SED fitting techniques and IR+UV conversion agree well. We find that surveys that preferablyselect star forming galaxies (e.g. by adopting Lyman-break, Hα or blue selection) typically predict a largermedian/average star formation rate at a fixed stellar mass especially for high mass objects, with respect tomass selected samples and hydrodynamic simulations. It has been reported in the literature that simulationsproduce steeper SFR-M∗ relations than observations. Interestingly, we find that updated observed star for-mation rate - stellar mass relations that are able to take into account faint small mass objects with low starformation rates tend to be steeper than previous estimates and actually in agreement with the predictionsfrom cosmological simulations.



Wednesday

17:00 − 18:00 No Title

Esteban Jimenez (PUC)

No Abstract

Wednesday

17:00 − 18:00Black hole Evolution in the EAGLE Universe

Yetli Rosas-Guevara (Universidad de Chile)

I will present the evolution of the black holes in the ‘Evolution and Assembly of GaLaxies and their Envi-ronments’ (EAGLE) cosmological hydrodynamic simulation suite. The largest of the EAGLE simulationscovers a (100cMpc)3 , including state-of-the-art physical models for star formation, blackhole accretion andtheir feedback . The subgrid physics introduced into the simulations depends only on the properties of gasand was calibrated to produce a virtual Universe that closely matches the observed properties of galaxies, inparticular the galaxy stellar mass function at z=0. Here, I will explore the main properties in the Evolutionof the black hole population in EAGLE such as black hole mass function and the evolution of the soft andhard X-ray luminosity functions of AGN.

Wednesday

17:00 − 18:00Determination of halo occupation distribution: Comparison between mock

and observational catalogues

Facundo Rodríguez (Intituto de Astronomía Teórica y Experimental)

Halo occupation distribution (HOD) is a powerful statistic that allows the study of several aspects of thematter distribution in the Universe, such as evaluating semi-analytic models of galaxy formation or im-posing constraints on cosmological models. The main goal of this project is to combine photometric andspectroscopic information using a discount method of background galaxies in order to compare the HODobtained from mock catalogues and observational data.

Wednesday

17:00 − 18:00Feasibility study of the Alcock-Paczynski cosmological test using cosmic

voids

Carlos Correa (Intituto de Astronomía Teórica y Experimental)

We propose an own implementation of the Alcock & Paczynski (1979) cosmological test (AP test) usingthe void-galaxy cross correlation function in redshift space. In essence, it only depends on a geometrical ef-fect: the evaluation of the ratio between the observed angular size and the radial/redshift size of an standard

ruler; so it is free of the evolution of galaxies. However, there are two main issues in practice: the absenceof genuine standard rulers and the contamination by dynamic distortions. To deal with them, we followeda similar procedure developed by Hamaus et al. (2015). On the one hand, we built an indirect standardruler: the features of the void-galaxy cross correlation function; while on the other hand, we used a phys-ically motivated and linear model for the dycotomic void dynamics (voids expanding & voids collapsing)developed by Paz et al. (2013). In order to apply the designed test, we used data from a large volume andhigh resolution simulation, the Millennium XXL (Angulo et al. 2012). Since large, deep and new galaxysurveys are coming soon (e.g. DESI, HETDEX, Euclid, eBOSS), we evaluated the sensitivity of the APtest analyzing its dependence with the mean redshift for which voids are identified. We found that at lowredshifts, there are some biasses due to a deficit in the linear model, while the test improves with increasingredshift, showing in this way, the impact of the next generation of surveys.



Wednesday

17:00 − 18:00Probing the growth of structure with different galaxy selections and redshift

uncertainties


Many ongoing and future large surveys are designed to map the spatial distribution of galaxies with dif-ferent strategies that optimise their required redshift range, accuracy and number density of objects. As aresult, very different galaxy populations will be used to trace the underlying matter structure. Furthermore,photometric and spectroscopic instruments will deliver very different redshift accuracies. We assess theimpact of these observational constraints on the performance of redshift-space distortions analysis. To dothis, we make use of a semi-analytical model of galaxy formation run over a large N-body simulation. Weexplore the predicted anisotropic clustering obtained from different galaxy selections and redshift uncertain-ties. Furthermore, by implementing two widely-used RSD models, we assess their performance recoveringcosmological parameters as a function of number density, galaxy type and redshift uncertainty. Our resultssuggest that galaxy formation can alter the expected shape and amplitude of the multipoles of the correlationfunction, especially in small scales. Hence, these calculations suggest a limit at which models cannot befurther refined, unless prior knowledge about the clustering properties of the galaxy populations is properlyaccounted for.

Wednesday

17:00 − 18:00Satellite Accretion in a ΛCDM Universe

Carolina Villalón (IATE)

We use a Dark Matter only simulation to study the accretion of satellites in the ΛCDM Model. The largevolume and resolution of the simulation enabled us to identify ∼366.000 massive host haloes (Mvir . 1012

M�) surrounded by ∼953.000 satellites. This sample allowed us to study the radial velocity profiles of allsatellites as a function of their distance to the primary object. Furthermore, we analysed the dependence ofthe radial velocity distribution with respect to the mass of the host and the properties of the haloes that arebeing accreted, such as their mass, shape and angular momentum.



Wednesday

17:00 − 18:00The Messi (Merging Systems Identification) Algorithm

Martín de los Rios (PUC)

In this work we present a new methodology for the identification of merging systems and the results ofits application to galaxy redshift surveys. We use as a starting point a mock catalogue of galaxy systems,identified using FoF algorithms, which experienced a major merger as indicated by its merger tree. Ap-plying machine learning techniques in this training sample, and using several features computed from theobservable properties of galaxy members, it is possible to select galaxy groups with a high probability ofhaving experienced a major merger. Next we apply a mixture of Gaussian technique on galaxy membersin order to reconstruct the properties of the haloes involved in such merger. This methodology providesa highly reliable sample of merging systems with low contamination and precisely recovered properties.We apply our techniques to samples of galaxy systems obtained from SDSS-DR7, WINGS and HeCS. Ourresults recover previously known merging systems and provide several new candidates.

Author Index

Adam Stevens, 3, 6, 16Alejandra Muñoz Arancibia, 2, 3, 6, 16Andrea Kulier, 2Andrés Meza, 3Andrés Ruiz, 3, 4, 13Andy Connolly, 3, 5, 8, 20Antonios Katsianis, 3, 9, 28Ariel Sanchez, 3, 4, 10, 12

Ben Moster, 3, 10, 25

Carlos Correa, 3, 9, 29Carlton Baugh, 2, 3, 7, 8, 21Carolina Villalón, 3Claudia Lagos, 3, 6, 10, 14Claudia Scoccola, 3, 5, 14Cristian Vega, 3, 10, 26

Dante Paz, 3, 9, 23Darren Croton, 3, 8, 22David Murphy, 3, 6, 18Diego Lambas, 3, 10

Enrique Paillas, 2–4, 13Eric Gawiser, 3, 7, 19Esteban Jimenez, 2, 3, 9, 29Ezequiel Treister, 3

Facundo Rodríguez, 3, 9, 29Francisco Castander, 3, 7, 19Francisco Förster, 3

Gaspar Galaz, 3, 9, 24Gian Luigi Granato, 3Guillermo Blanc, 3, 7, 18

Idit Zehavi, 3–5, 14Iván Lacerna, 2, 3, 9, 23

Jaime Forero-Romero, 3Jeremy Tinker, 3, 10, 24Joaquín Armijo, 2Joaquín Prieto, 3, 9, 27Joe DeRose, 3, 10, 25

Johan Comparat, 3, 8, 20Julian Mejia-Restrepo, 3

Lucas Bignone, 3, 9, 27

Madusha Gunawardhana, 2Mariano Domínguez, 3, 10, 25Mario Sgro, 3, 9, 27Martín Moyano, 3María Celeste Artale, 3, 6, 15Matthieu Schaller, 3, 6, 15Matías Bravo, 2, 3, 9, 28

Nelson Padilla, 2, 3, 6, 17Nicolás Meza, 3Nuala McCullagh, 3, 5, 14

Patricia Tissera, 3, 6, 10, 16Paulina Troncoso, 2, 3, 8, 19Peder Norberg, 2–4, 12

Roberto Gonzalez, 2, 3, 9, 24Roberto Muñoz, 3, 8, 21

Salvador Salazar, 3, 9, 23Sebastián López, 3Sergio Contreras, 2, 3, 6, 10, 17Shaun Cole, 3–5, 11Shirley Ho, 3, 6, 7, 18Silvio Rodríguez, 3, 4, 12Sofia Cora, 3, 8, 21Susana Pedrosa, 3, 8, 22

Tomas Muller, 3

Violeta Gonzalez-Perez, 3, 6, 15

Yanchuan Cai, 3, 8, 22Yetli Rosas-Guevara, 3, 9, 29

Zheng Zheng, 3, 4, 13Zhenya Zheng, 3, 4, 11

Álvaro Orsi, 3, 4, 11, 30



Date post:	20-Sep-2018
Category:	Documents
Upload:	halien
View:	214 times
Download:	0 times

Mock Santiago - astro.puc.cl · Mock Santiago 2016 Preparing for the Next Generation Surveys 18 22...

Documents