ESO ASTROPHYSICS SYMPOSIA European Southern Observatory978-3-540-71173-5/1.pdf · ESO ASTROPHYSICS...

ESO ASTROPHYSICS SYMPOSIAEuropean Southern Observatory———————————————————Series Editor: Bruno Leibundgut

I. Saviane V.D. Ivanov J. Borissova (Eds.)

Groups of Galaxiesin the Nearby UniverseProceedingsof the ESO Workshop heldat Santiago de Chile, December 5-9, 2005

ABC

Volume Editors

Ivo SavianeValentin D. IvanovESOAv. de Cordova 3107Santiago, Chile

Series Editor

Bruno LeibundgutEuropean Southern ObservatoryKarl-Schwarzschild-Str. 285748 GarchingGermany

Jordanka BorissovaUniversidad de ValparaisoAv. Gran Bretana 1111Casilla 5030Valparaiso, Chile

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Preface

This volume contains the proceeding of an international conference held inSantiago, Chile, in December 2005. The meeting was attended by nearly ahundred active researchers in the field. The following is the reproduction ofan article that appeared in the March 2006 issue of the ESO Messenger.

Groups of Galaxies in the Nearby Universe

For every galaxy in the field or in clusters, there are about three galaxies ingroups. Therefore, the evolution of most galaxies actually happens in groups.The Milky Way resides in a group, and groups can be found at high redshift.The current generation of 10-m class telescopes and space facilities allows tostudy members of nearby groups with exquisite detail and their properties canbe correlated with the global properties of their host group. Finally, groupsare relevant for cosmology, since they trace large-scale structures better thanclusters, and the evolution of groups and clusters may be related.

Strangely, there are three times less papers on groups of galaxies than onclusters of galaxies, as revealed by an ADS search. Organizing this conferencewas a way to focus the attention of the community on the galaxy groups. Wealso wanted to offer a venue where people coming from various research fieldscould meet and discuss groups from different perspectives. All this happenedin a friendly atmosphere created by hotel Torremayor in Santiago.

The discussion was organized in seven sessions, introduced by invitedreviews: Eva Grebel (Local Group vs. Nearby Groups), Vince Eke (GroupsSearches and Surveys), Chris Conselice (The Evolution of Galaxies in Groups– Observations), Gary Mamon (The Evolution of Galaxies in Groups – The-ory), Ann Zabludoff (Evolution of Groups as Systems), Trevor Ponman (In-terstellar Medium and Intragroup medium), Stefano Borgani (Groups in aCosmological context), and finally Ken Freeman (Conference Summary).There were almost 50 contributed talks and 30 posters. In the following textwe give a short summary of the main conference ideas, mostly based on theinvited reviews.

All You Wanted To Know About Groups (But You Were Afraid To Ask)

Groups are bound structures with masses in the range m = 1012−14M�(Eke), containing less than 50 galaxies (Conselice), and with typical sizes of

VI Preface

a few Mpc. Groups detected in X-rays have luminosities of LX = 1041−43

erg sec−1 and gas temperatures of kT = 0.1 − 3 keV (Ponman). Most ofthe stellar mass in the present universe is in groups similar to the LocalGroup with masses 2 × 1012M� and only 2% is in clusters with m > 5 ×1014M� (Eke). Groups were already present at redshifts z > 1 (Conselice).Cosmological simulations predict a much larger number of galaxy satellitesthan observed, and HI high velocity clouds cannot fill in this gap (Pisano).Groups follow a fundamental plane (Muriel) and the most massive ones havean X-ray halo with an extended component (Zabludoff).

A special class of groups are the so-called ‘fossil groups’ – isolated ellip-ticals with properties similar to a group, which could be the final stage of acollapsed group. However, most isolated ellipticals are not collapsed groups(Forbes). There are only 15 fossil groups known to date.

The evolution of low velocity dispersion groups is dominated by mergers,which could explain the bimodal mass function of the X-ray faint groups(X-ray faint groups tend to have low velocity dispersion and vice versa),if intermediate-mass members merge to build the largest group members(Raychaudhury). The bimodal mass function, similar to that of clusters, isconfirmed in compact groups (Bomans). Compared to compact groups, theloose ones tend to have fewer low-mass members.

The results presented here were obtained thanks to large observational ef-forts (Table 1). Historically, the first group catalogs were biased toward com-pact groups, which are the easiest to identify from imaging surveys. Modernredshift surveys allow selections including recession velocities, and finding al-gorithms can be tested on mock catalogs generated with dark matter (DM)simulations (Eke).

Galaxies in Groups

Galaxies in groups can be affected by processes like ram pressure stripping,interactions and harassment, mergers, group tidal field, gas loss and sup-pressed star formation (also known as strangulation or suffocation). Mergingis the most important of these because of the low relative velocities of galaxiesin groups in comparison with the galaxies in clusters. Simulations show thatmergers induce an intense and brief (of the order of a hundred Myr) surgeof star formation before the final coalescence into a spheroid, which evolvespassively afterwards. Simultaneously, mergers transfer momentum from theinteracting galaxies to the group as a whole, thereby increasing the groupvelocity dispersion. Indeed, observations show that there are more spheroidsin groups with higher velocity dispersion (Zabludoff).

Eventually, the feedback from the residual black-hole and active galacticnucleus (AGN) reduces the star formation by a factor of ten or more. At least50% of galaxies in compact groups are low-luminosity AGNs (Martinez), whilethe field fraction is only 30%. Moreover, the cores of X-ray groups are oftendisturbed, which could be additional evidence for AGN feedback (O’Sullivan).

Preface VII

The selective suppression of star formation in larger group members could ex-plain the downsizing phenomenon – the decrease of the maximum luminosityof star-forming galaxies at lower redshifts. Mergers occur mostly at redshiftsz > 1, for example at z = 2.5 about 50% of bright galaxies are undergoingmergers, while today only 2% of galaxies merge per Gyr (Conselice). Most ofthe stars in group members also formed between redshifts z = 2.5 and 1.

Locally, environmental effects can be traced directly by reconstructingstar formation histories of individual galaxies. For example, the fraction ofintermediate-age stars of Milky Way dwarf satellites depends on their dis-tance from the Galaxy. On the contrary, this fraction is constant in M81satellites (Da Costa) probably due to the compactness of the M81 group,where multiple close encounters have homogenized their star formation his-tories.

The Evolution of Groups

The origin of groups is probably related to large-scale gaseous filaments athigh redshift. Before virialization, smooth accretion, super novae and AGNactivity enhance the entropy, and the metal-enriched gas cannot be retainedby the shallow potential of pre-collapse groups (Ponman, Borgani). Duringthe virialization, the central spheroidals grow via mergers. Early-type starsand enriched gas become part of the intragroup environment. Eventually, acommon dark matter and a hot (X-ray) gas halos are formed (Zabludoff).The X-ray emission increases, and the X-ray halo becomes more and moreregular. Later, the diffuse DM distribution will reduce the merger rate andmoderate the evolution of groups. At least a fraction of groups end their livesas fossil groups.

Most low-redshift groups are just detaching from the Hubble flow, as sug-gested by the time evolution of the virial mass to light ratio (Mamon). Inparticular, the detachment for the Local Group occurred at z < 0.7 (Free-man). The mass-temperature and mass-luminosity distributions in the X-raysfor clusters and groups can constrain the cosmological parameters (Borgani).

To summarize, as a group evolves, the dwarf-to-giant ratio, early-typegalaxy fraction, intragroup starlight and metallicity, the velocity dispersion,and the mass of the central giant elliptical grow. The metallicity of the in-tragroup medium also increases thanks to the intragroup stars, whose ejectado not have to overcome galactic potential wells (Zabludoff).

Observations are consistent with this scenario. As mentioned above,groups with higher velocity dispersions have higher fractions of early typegalaxies. And the intragroup medium can be responsible for stripping, e.g. ofNGC 2276 in the NGC 2300 group (Ponman). In turn, stripping enhances thefraction of passive galaxies in groups. Further observational support for thisevolutionary scheme are the constant radial profiles of velocity dispersion,which point to a common DM halo. Next, if the early enrichment history ofthe intragroup gas is dominated by type II supernovae, and the late history by

VIII Preface

type Ia supernovae, then this could explain the observed decrease of the over-all metallicity toward the outskirts of the group and the alpha-enhancementin the outer parts of groups (Rasmussen) because the early ejecta had timeto spread across the group.

Groups and Clusters of Galaxies

It was realized during the conference that groups are important for the evo-lution of clusters as well. Clusters may grow by accretion of groups, as ex-emplified by the Eridanus Super-group infalling toward Fornax (Brough).Therefore, some cluster properties might be explained by groups, like the X-ray medium, high dwarf to giant galaxy ratio, brightest cluster galaxies andthe early-types galaxy fraction (especially in more massive groups).

Likewise, the evolution of galaxies in clusters might be dominated bygroup-scale environment, driving, e.g. the morphology-environment relation,the Butcher-Oemler effect, and the brightest cluster galaxies formation. Forexample, the intra-cluster light in Virgo probably originates in tidal inter-actions inside group-size structures (Mihos), favoured by their low velocitydispersion. Since tidal features are erased as clusters evolve, the presenceof such features would indicate that the cluster is dynamically young, still’fragmented’ in groups.

Although mergers can happen both in clusters and groups, the high ve-locity dispersion in clusters leads to less efficient orbital-decay-type mergers,while more efficient, direct head-on mergers are common in groups, especiallythe evolved, X-ray bright ones (Mamon). This can explain the higher frac-tion of early type galaxies in this class of groups compared to the field andclusters.

These few paragraphs could only give a brief sense of the stimulatingdiscussion during the five days of the conference, and we hope that all par-ticipants went away with fresh views on the current status of galaxy groupsstudies. The entire proceedings of the symposium are presented in this vol-ume.

We would like to express our gratitude to the members of the SOC, andespecially of the SOC Chair Duncan Forbes, for their efforts that made itpossible to organize this meeting. Last but not least, the success of the con-ference would have been impossible without the excellent work of Maria Eu-genia Gomez, Paulina Jiron and Ismael Martınez, and the financial supportof ESO.

Santiago de Chile Ivo SavianeNovember 2006 Valentin D. Ivanov

Jordanka Borissova

Contents

Part I Local Group versus Nearby Groups

Local Group(s)E.K. Grebel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

The Local Group Dwarfs ComparedE.D. Skillman . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Galaxy Groups in the Local Volume: An HI PerspectiveB.S. Koribalski . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

HI in Local Group Analogs: What does it Tell Us aboutGalaxy Formation?D.J. Pisano, D.G. Barnes, B.K. Gibson, L. Staveley-Smith,K.C. Freeman and V.A. Kilborn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Stellar Metallicities and Ages in Leo I dSphM. Gullieuszik, I. Saviane, E.V. Held and L. Rizzi . . . . . . . . . . . . . . . . . 39

Globular Clusters in M31 and the Local GroupS.C. Kim, M.G. Lee, D. Geisler, A. Sarajedini, W.E. Harris,H.S. Park, H.S. Hwang and J.C. Seguel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Properties of RR Lyrae Stars in the Inner Regions of theLarge Magellanic Cloud. II. The Extended SampleJ. Borissova, D. Minniti, M. Rejkuba and D. Alves . . . . . . . . . . . . . . . . . . 45

Diffuse Ionized Gas in the Dwarf Galaxy DDO 53N. Flores-Fajardo and A.M. Hidalgo-Gamez . . . . . . . . . . . . . . . . . . . . . . . . 47

Part II Groups Searches and Surveys

Galaxy Group Searches and SurveysV. Eke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

X Contents

Baryon Budget in 2 keV Galaxy GroupsA. Hornstrup, A. Vikhlinin, R. Burenin, H. Ebeling, O. Kotov,K. Pedersen, H. Quintana and J. Rasmussen . . . . . . . . . . . . . . . . . . . . . . 67

Isolated Compact Groups of Galaxies in the 2dF GalaxyRedshift SurveyJ. Saucedo-Morales and P. Loera-Gonzalez . . . . . . . . . . . . . . . . . . . . . . . . . 73

Environmental Effects on Galaxy Evolution Based on theSloan Digital Sky SurveyT. Goto . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

DPOSS II Compact Groups: The EMMI/NTT SurveyE. Pompei, A. Iovino and R.R. de Carvalho . . . . . . . . . . . . . . . . . . . . . . . . 85

The Low-luminosity Galaxy Populationin the NGC 5044 GroupS.A. Cellone and A. Buzzoni . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

The Galaxy Evolution Multi-wavelength Study (GEMS)ProjectD.A. Forbes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

A Search for Ultra-compact Dwarf Galaxies in the NGC1023 Group of GalaxiesS. Mieske, M.J. West and C.M. de Oliveira . . . . . . . . . . . . . . . . . . . . . . . . 103

Dwarf Galaxies in the Antlia Cluster: First ResultsA.V.S. Castelli, L.P. Bassino, S.A. Cellone, T. Richtler, B. Dirsch,L. Infante, C. Aruta and M. Gomez . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Compact Groups: A Statistical AnalysisE. Dıaz, C. Ragone, H. Muriel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

Study of Intracluster Diffuse Light within the Fornax ClusterA.C. Cardenas, S.A. Cellone and J.C. Forte . . . . . . . . . . . . . . . . . . . . . . . 113

BVRI Photometric Analysis for the Galaxy Group NGC 4410J.A.P. Grana, S.N. Kemp, A.C. Katsiyannis, E. de la Fuente,A. Franco-Balderas and J. Meaburn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

Photometric and Kinematical Study of Nearby Groupsof Galaxies Around IC 65 and NGC 6962J. Vennik and E. Tago . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

Contents XI

Part III Evolution of Galaxies in Groups – Observational

The History of Galaxy Formation in Groups: AnObservational PerspectiveC.J. Conselice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Deep Optical Imaging of ESO 383–45: A Galaxy UndergoingRam-pressure Stripping, or a Tidal Merger Remnant?S.N. Kemp, E. de la Fuente, A. Franco-Balderas and J. Meaburn . . . . . 139

Morphologies and Star Formation in z ∼ 0.5 Group GalaxiesD.J. Wilman, M.L. Balogh, R.G. Bower, J.S. Mulchaey, A.Oemler Jnr and R.G. Carlberg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

Formation and Evolution of Early-type GalaxiesC. Chiosi and E. Merlin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

Dwarf Galaxies in Hickson Compact GroupsD.J. Bomans, E. Krusch, R.-J. Dettmar, V. Muller and C. Taylor . . . 157

Low Luminosity Activity in Hickson Compact GroupsM.A. Martinez, A. del Olmo, J. Perea and R. Coziol . . . . . . . . . . . . . . . . 163

Dwarf Elliptical Galaxies in Cen A GroupM. Rejkuba . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

Stellar Populations in Compact Group Elliptical GalaxiesI.G. de la Rosa, R.R. de Carvalho, A. Vazdekis and B. Barbuy . . . . . . . 175

Spitzer 4.5 µm Luminosity-Metallicity and Mass-MetallicityRelations for Nearby Dwarf Irregular GalaxiesH. Lee, E.D. Skillman, J.M. Cannon, D.C. Jackson, R.D. Gehrz,E. Polomski and C.E. Woodward . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

Shapes and Galaxy Flows Around Clustersand Groups of GalaxiesN. Padilla . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187

Infrared Surface Brightness Analysisof Galaxies in Compact GroupsI. Plauchu-Frayn, R. Coziol and H. Bravo-Alfaro . . . . . . . . . . . . . . . . . . . . 193

Size and Orientation of the ‘Z’ in ZRGsC. Zier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195

XII Contents

IMF Model Sampling and the Emission Linesin Star Forming GalaxiesG. Magris C., F. Molina and A. Parravano . . . . . . . . . . . . . . . . . . . . . . . . 197

Part IV Evolution of Galaxies in Groups – Theoretical

The Evolution of Galaxy Groups and of Galaxies ThereinG.A. Mamon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203

Diffuse Starlight and the Evolution of Groups and Clustersof GalaxiesJ.C. Mihos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221

Simulating Diffuse Light in Galaxy ClustersC.S. Rudick, J.C. Mihos and C. McBride . . . . . . . . . . . . . . . . . . . . . . . . . . 227

Lensing by GroupsO. Moller, M. Kitzbichler, V.R. Eke and P. Natarajan . . . . . . . . . . . . . . . 233

The Role of Tidal Interactions in Driving Galaxy EvolutionJ. Perez, P.B. Tissera, D.G. Lambas, C. Scannapieco andM.E. De Rossi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239

Chemical and Photometric Evolution of NGC 6822 in aCosmological ContextL. Carigi, P. Colın and M. Peimbert . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241

Evolution of the Luminosity-Metallicity-Stellar MassCorrelation in a Hierarchical ScenarioM.E. De Rossi, P.B. Tissera and C. Scannapieco . . . . . . . . . . . . . . . . . . . 243

Part V Evolution of Groups as Systems

Groups: The Rich, the Poor and the DestituteA. Zabludoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249

The Eridanus SupergroupS. Brough . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261

ClG J1205 + 4429, the Most Distant Fossil Group at z = 0.59F. Durret, M.P. Ulmer, C. Adami G. Covone and G.B. Lima Neto . . . . 267

Past and Future of CG J1720-67.8: Constraints fromObservations and ModelsS. Temporin and W. Kapferer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273

Contents XIII

The Optical and Near-infrared Properties of Nearby Groupsof GalaxiesS. Raychaudhury and T.A. Miles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279

Halo Shapes, Dynamics and EnvironmentM. Plionis, C. Ragone and S. Basilakos . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285

II Zwicky 23 and FamilyE.H. Wehner, J.S. Gallagher, G.C. Rudie and P.J. Cigan . . . . . . . . . . . . 291

Dynamical Analysis of NGC 5128 and the Centaurus GroupK.A. Woodley . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297

Seyfert’s Sextet (HGC 79): An Evolved Stephan’s Quintet?A. Durbala, J. Sulentic, M. Rosado, A. del Olmo, J. Pereaand H. Plana . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301

Part VI Interstellar Medium and Intragroup Medium

The HI Content of a Sample of Groups with DifferentDynamical AgesE.E. Freeland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307

Neutral Hydrogen in Galaxy GroupsV.A. Kilborn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313

Environmental Effects on Clusters at z = 0.2: Strong GalaxyDisruption in A 2667 and A 1689H. Bravo–Alfaro, L. Cortese, G. Covone and J.-P. Kneib . . . . . . . . . . . . 319

Metallicity Structure in X-ray Bright Galaxy GroupsJ. Rasmussen and T.J. Ponman . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325

An X-ray View of the Cores of Galaxy Groups: Effectsof AGN and Mergers on the IGME. O’Sullivan and J.M. Vrtilek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331

Active Galaxies, Thermal Conduction and Entropy of Gasin Galaxy Groups and ClustersS. Roychowdhury . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337

Stellar and Ionized Gas Kinematics of Peculiar VirgoCluster GalaxiesJ.R. Cortes, J.D.P. Kenney and E. Hardy . . . . . . . . . . . . . . . . . . . . . . . . . 343

XIV Contents

ISM of Galaxies in Extremely Different Environments:Isolated vs Compact GroupsL. Verdes-Montenegro, M. S. Yun, S. Borthakur, D. Espada, I. Sellim,E. Athanassoula, G. Bergond, A. Bosma, F. Combes, E. Garcia,W.K. Huchtmeier, S. Leon, U. Lisenfeld, S. Odewahn, T. Ponman,J. Rasmussen, J. Sabater, J. Sulentic and S. Verley . . . . . . . . . . . . . . . . 349

Comparing Semi-Analytical and Numerical Modelling of theICM Chemical EnrichmentS.A. Cora, L. Tornatore and S. Borgani . . . . . . . . . . . . . . . . . . . . . . . . . . . 355

Part VII Groups in a Cosmological Context

Groups and Clusters of Galaxies in Cosmological ContextS. Borgani . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361

The Association of Compact Groups of Galaxies withLarge-scale StructuresH. Andernach and R. Coziol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379

Probing the Environment with Galaxy DynamicsA.J. Romanowsky . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391

The Internal Dynamics of A115 Nearby Cluster of GalaxiesR. Barrena, W. Boschin and M. Girardi . . . . . . . . . . . . . . . . . . . . . . . . . . 391

Dynamics of the Radio–halo Cluster A2744: An Optical StudyW. Boschin, R. Barrena, M. Girardi and M. Spolaor . . . . . . . . . . . . . . . . 393

Dynamics and Shape of Brightest Cluster GalaxiesH. Andernach, K. Alamo-Martınez, R. Coziol and E. Tago . . . . . . . . . . . 395

Author Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397

List of Contributors

Andernach HeinzUniversidad de GuanajuatoMexicoheinz@astro.ugto.mx

Barrena RafaelInstituto de Astrofisica de CanariasSpainrbarrena@iac.es

Bassino LiliaUniversidad Nacional de La PlataArgentinalbassino@fcaglp.unlp.edu.ar

Bomans DominikRuhr-University BochumGermanybomans@astro.rub.de

Borgani StefanoUniversita di TriesteItalyborgani@oats.inaf.it

Borissova JordankaESOChilejborisso@eso.org

Brasileiro FranciscaIAGUniv. de Sao PauloBrazilchica@astro.iag.usp.br

Bravo-Alfaro HectorUniversidad de GuanajuatoMexicohector@astro.ugto.mx

Brough SarahSwinburne UniversityAustraliasbrough@astro.swin.edu.au

Carigi LeticiaInstituto de Astronomia - UNAMMexicocarigi@astroscu.unam.mx

Cellone SergioUniversidad Nacional de La PlataArgentinascellone@fcaglp.unlp.edu.ar

Chiosi CesarePadova UniversityItalychiosi@pd.astro.it

Chomiuk LauraUniversity of Wisconsin-Madisonchomiuk@astro.wisc.edu

Cifuentes Cardenas AlejandroUniversidad Nacional de La PlataArgentinaacifuentes@fcaglp.unlp.edu.ar

Coenda ValeriaIATE, Obs. Astron. de CordovaArgentinavcoenda@oac.uncor.edu

XVI List of Contributors

Conselice ChristopherUniversity of NottinghamUKcc@astro.caltech.edu

Cooray AsanthaUniversity of CaliforniaIrvineUSAacooray@uci.edu

Cora Sofia AlejandraInst. deAstr. de LaPlata, CONICETArgentinasacora@fcaglp.unlp.edu.ar

Cortes JuanUniversidad de Chilejcortes@das.uchile.cl

Da Costa GaryMt Stromlo Obs. RSAAANUAustraliagdc@mso.anu.edu.au

De Rossi Maria EmiliaIATEObs. Astron. de CordovaArgentinamaribblue@hotmail.com

Diaz EugeniaIATEObs. Astron. de CordovaArgentinaeuge@mail.oac.uncor.edu

Durret FlorenceIAPFrancedurret@iap.fr

Eke VincentUniversity of DurhamUKv.r.eke@durham.ac.uk

Flores NahielyInstituto de Astronomia - UNAMMexiconahiely@astroscu.unam.mx

Forbes DuncanSwinburne UniversityAustraliadforbes@swin.edu.au

Freeland EmilyUniversity of WisconsinUSAfreeland@astro.wisc.edu

Freeman KenMt Stromlo Obs.RSAAANUAustraliakcf@mso.anu.edu.au

Garcia de la Rosa I.IAC (Spain) - IAG (Brazil)ignacio@astro.iag.usp.br

Gastaldello FabioUniversity of CaliforniaIrvineUSAgasta@uci.edu

Geisler DougUniversidad de ConcepcionChiledgeisler@astro-udec.cl

Giovanelli RiccardoCornell UniversityUSAriccardo@astro.cornell.edu

Goto TomotsuguJapan Aerospace ExplorationAgencyJapantomo@ir.isas.jaxa.jp

List of Contributors XVII

Grebel Eva K.University of BaselSwitzerlandgrebel@astro.unibas.ch

Gullieuszik MarcoPadova University/ESOItalygullieus@pd.astro.it

Hau GeorgeDurham UniversityUKgeorge.hau@durham.ac.uk

Hernandez-Martinez L.Instituto de Astronomia - UNAMMexicolhernand@astroscu.unam.mx

Hibbard JohnNRAOUSAjhibbard@nrao.edu

Hornstrup AllanDanish National Space CenterDenmarkallan@spacecenter.dk

Infante LeopoldoPontificia Universidad CatolicaChilelinfante@astro.puc.cl

Ivanov ValentinESOChilevivanov@eso.org

Jeltema TeslaCarnegie ObservatoriesUSAtesla@ociw.edu

Kemp SimonUniversidad de GuadalajaraMexicosnk@astro.iam.udg.mx

Kilborn VirginiaSwinburne UniversityAustraliavkilborn@swin.edu.au

Kim Sang ChulAstr. and Space Science Inst.Koreasckim@kasi.re.kr

Koribalski Baerbel S.Austr. Tel. Nat. FacilityEppingAustraliaBaerbel.Koribalski@atnf.csiro.au

Lares MarceloIATEObs. Astron. de CordovaArgentinamlares@mail.oac.uncor.edu

Lee HenryUniversity of MinnesotaUSAhlee@astro.umn.edu

Lynam PaulESOChileplynam@eso.org

Magris GladisCIDAVenezuelamagris@cida.ve

Mamon GaryIAPFrancegam@iap.fr

XVIII List of Contributors

Martinez Carballo M. A.Instituto de Astrof. de Andalucia-CSICSpaingeli@iaa.es

Mazzotta PasqualeCfA, USA – Univ. of Roma “TorVergata”Italymazzotta@roma2.infn.it

Mieske SteffenESO/GarchingGermanysmieske@eso.org

Mihos ChristopherCase Western Reserve Univ.ClevelandUSAmihos@case.edu

Moller OleMPAGarchingGermanyole@mpa-garching.mpg.de

Motta VeronicaPontificia Universidad CatolicaChilevmotta@astro.puc.cl

Muriel HernanIATEObs. Astron. de CordovaArgentinahernan@oac.uncor.edu

Oliveira C. M. deUniversidade de Sao PauloBraziloliveira@astro.iag.usp.br

O‘Mill Ana LauraIATEObs. Astron. de CordovaArgentinaaomill@oac.uncor.edu

O‘Sullivan EwanCfAUSAeosullivan@head.cfa.harvard.edu

Padilla NelsonPontificia Universidad CatolicaChilenpadilla@astro.puc.cl

Paz DanteIATEObs. Astron. de CordovaArgentinadpaz@oac.uncor.edu

Perez Grana ArturoUniversidad de GuadalajaraMexicorivenzhell@yahoo.com

Perez Maria JosefaUniversidad Nacional de La PlataArgentinajperez@fcaglp.unlp.edu.ar

Plauchu-F. IlseUniversidad de GuanajuatoMexicoplauchuf@astro.ugto.mx

Plionis ManolisINAOE-Mexico & NOA-Greecemplionis@inaoep.mx

Pompei EmanuelaESOChileepompei@eso.org

List of Contributors XIX

Ponman TrevorUniversity of BirminghamUKtjp@star.sr.bham.ac.uk

Ragone F. CinthiaIATEObs. Astron. de CordovaArgentinacin@oac.uncor.edu

Rasmussen JesperUniversity of BirminghamUKjesper@star.sr.bham.ac.uk

Raychaudhury SomakUniversity of BirminghamUKsomak@star.sr.bham.ac.uk

Rejkuba MarinaESO/GarchingGermanymrejkuba@eso.org

Rodriguez-Gonzalez AryINAOE-Mexicoary@inaoep.mx

Romanowsky AaronUniversidad de ConcepcionChileromanow@astro-udec.cl

Rosado MargaritaInstituto de Astronoma - UNAMMexicomargarit@astroscu.unam.mx

Roychowdhury SuparnaRaman Research InstituteBangaloreIndiasuparna@rri.res.in

Rudick CraigCase Western Reserve Univ.ClevelandUSAcraig@fafnir.astr.cwru.edu

Saucedo-Morales JulioUniversidad de SonoraMexicojsaucedo@astro.uson.mx

Saviane IvoESOChileisaviane@eso.org

Skillman Evan D.University of MinnesotaUSAskillman@astro.umn.edu

Smith AnaliaUniversidad Nacional de La PlataArgentinaasmith@fcaglp.unlp.edu.ar

Vennik JaanTartu ObservatoryEstoniavennik@aai.ee

Verdes-Montenegro L.Inst. de Astrof. de Andalucia-CSICSpainlourdes@iaa.es

Wehner ElizabethMcMaster UniversityCanadawehner@astro.wisc.edu

Wilman DavidMPI f. Extraterrestrial PhysicsGermanydwilman@mpe.mpg.de

XX List of Contributors

Woodley KristinMcMaster UniversityCanadawoodleka@physics.mcmaster.ca

Zabludoff AnnUniversity of ArizonaUSAazabludoff@as.arizona.edu

Zandivarez ArielIATEObs. Astron. de Cordova

Argentinaarielz@mail.oac.uncor.edu

Zier ChristianRaman Research InstituteBangaloreIndiachzier@rri.res.in

Zimer MarcMPE / University of ViennaAustriazimer@astro.univie.ac.at