The Origins of the Intracluster Light
|
|
- Shonda Warren
- 5 years ago
- Views:
Transcription
1 The Origins of the Intracluster Light 1. Introduction The discovery and quantification of the diffuse intracluster starlight (ICL) in clusters (e.g. Zwicky 1951; Uson et al. 1991; Feldmeier et al. 2002, 2004; Gal-Yam et al. 2003; Aguerri et al. 2006) has provided a new tool with which to study the history and structure of galaxy clusters in greater detail than has hitherto been possible. ICL consist of stars in galaxy clusters which have been gravitationally stripped from their parent galaxies via cluster galaxies interacting with other galaxies or with the cluster potential (e.g. Napolitano et al. 2003; Willman et al. 2004; Arnaboldi et al. 2004; Rudick et al. 2006, hereafter Paper I). As a product of the dynamical interactions within the cluster, the ICL has the potential to reveal a great deal of information about the cluster s accretion history and evolutionary state, as well as the mass distribution of the cluster galaxies and the cluster as a whole. The quantity, morphology, and kinematics of the ICL each hold potentially useful information on the cluster s evolution, and processes affecting individual galaxies can be traced using individual ICL streams. In Paper I we used N-body simulations to study the evolution of ICL in clusters as they evolve in a ΛCDM universe. In that paper we were able to isolate close encounters between galaxies and groups of galaxies within the cluster as an important mechanism driving the production of ICL. We now propose to continue our analyses of these clusters in order to further understand the nature of the ICL. Our primary motivation is to better relate the observable features of the ICL to physical mechanisms which produce it, in order to better understand the structure and evolution of galaxy clusters and their constituent galaxies. Our objectives will be to study the kinematics of the ICL as could be sampled observationally by planetary nebulae, to study the relationships between the various observational and theoretical definitions of ICL currently in use, and to study how the properties ICL are effected by the intrinsic properties of its host cluster. 2. Simulated PNe Observations of ICL Kinematics 2.1. Introduction A recent advance in the study of ICL has come with spectroscopic observations of planetary nebulae from the intra cluster stellar population (ICPNe), providing a tool with which to study the kinematics of the ICL (Arnaboldi et al. 2004; Gerhard et al. 2005). While currently these studies consist of only small samples of ICPNe, covering a small fraction of the angular extent of the clusters, they have already had some success in identifying intracluster stars as having velocities distinct from neighboring cluster galaxies, even when these stars are projected onto the face of a bound galaxy. As sample sizes and areal coverage improve, these data will provide valuable information on the relaxation state, distribution, and origins of the ICL.
2 2 With these new observations of ICL kinematics have come corresponding efforts to model the ICL dynamics in cluster simulations. Both Napolitano et al. (2003) and Willman et al. (2004) measure the velocity distribution of the ICL along individual lines of sight at z = 0, and find significant substructure, indicated by non-gaussian distributions. Each concludes that the substructure exists due to incomplete phase mixing of the tidal streams produced by strong interactions between galaxies and groups of galaxies within the cluster, which are the source of the ICL. Additionally, Willman et al. (2004) attempt to relate the ICL velocity distribution to the underlying mass distribution of the cluster, and find that the ICL velocity distribution yields systematically low estimates of the cluster mass. Sommer-Larsen et al. (2005) also studied the kinematics of the ICL and found that the ICL is dynamically colder than the cluster galaxies. However, Sommer-Larsen (2006) found that dynamical state of the ICL is related to the dynamical state of the cluster itself. In an effort to explore this burgeoning new field, we propose to extend our analyses of the galaxy cluster simulations initially presented in Paper I to study the kinematic properties of the ICL. An important result of Paper I is the conclusion that the dominant mechanism driving the production of ICL is the tidal stripping of material during strong encounters between groups of galaxies within the cluster. It was also shown that the morphology of the ICL evolves from one dominated by long, thin filaments early in the cluster s history to becoming a more diffuse halo around the cluster center at later times. Both of these observations are consistent with an evolutionary scenario in which ICL is tidally stripped from galaxies and groups in dynamically cold tidal streams, and becomes slowly phase mixed as the cluster evolves. This is a similar situation to the one studied by Harding et al. (2001) in which dwarf galaxies are tidally disrupted in a static Milky Way potential, and is precisely the scenario suggested by both theoretical (Napolitano et al. 2003; Willman et al. 2004) and observational (Arnaboldi et al. 2004) studies of ICL. While there is now broad agreement on the general mechanism which gives rise to the ICL, many questions remain about how the phase space structure evolves and how it relates to the dynamical state of cluster, as well as how the interactions which create the ICL affect the specific evolution of the galaxies from which it is stripped. If the the ICL evolves from a complex of cold tidal streams into a single phase mixed halo, on what time scales does this mixing occur? Can we use the cold tidal streams to map the orbits, and thus the interaction histories, of the cluster galaxies? Is the relaxation state of the ICL related to the accretion history and dynamical age of the cluster? With potentially thousands of discrete kinematic tracers, can we use the ICL to determine the underlying gravitational potential of the cluster? We intend to focus our efforts on three major areas: identifying ICL substructures; following the detailed origins and evolution of individual substructures; and using the dynamical state of the ICL to determine cluster mass and evolutionary state. Detailed descriptions of these and other analyses are provided below Simulated Observations A key element of any analysis of astronomical simulations is devising methods to observe the simulated data, in order to extract the desired information. Furthermore, our group in particular puts a prime
3 3 focus on understanding the simulations using observationally tractable data, i.e. data which could actually be observed in astronomical objects using current or near-future technology. In this case in which we are studying the dynamics of ICL, this means observing the projected positions and line-of-sight velocities of ICPNe. We have already begun work on developing several tools with which to study our simulated clusters, given these observational constraints ICL Phase Space Evolution In Paper I we presented surface brightness maps of our clusters using an arbitrary projection, and showed that the observed evolution of the clusters is independent of projection angle. Using the same projections, Figures 1 3 show preliminary maps of the mean velocity and velocity dispersion of the particles at each position in one of these simulated clusters. In this way we can examine the phase space structure of the ICL throughout the cluster. Furthermore, we can create sequences of these maps at consecutive timepoints in the clusters evolution in order to watch the phase space structure of the ICL evolve. Using the surface brightness maps presented in Paper I, we will be able to correlate the phase space evolution of the cluster with the observed dynamical history of the cluster, much as we did with the ICL production rate in Paper I. Furthermore, we intend to create Fabry-Pérot style data cubes in velocity space, in which we will observe the particles in a series of small velocity intervals, in order to get a more detailed view of the phase space structure of the cluster at any given time point. Because clusters can only be observed in twodimensional projection, measurements of the velocity distribution provide a unique method with which to deproject the cluster, if only in phase space rather than physical space. However, this technique is useful for separating dynamically distinct sub-groups within the cluster, and Arnaboldi et al. (2004) showed that phase space measurements can separate ICL from bound cluster galaxies projected onto the same line of sight. A final technique that will prove useful in studying the evolution of ICL will be a scheme of particle tagging, whereby we can trace the evolution of individual particles. This will allow us to understand the origins of the ICL in much more detail and trace the evolution of individual streams. For example, we can identify tidal streams consisting of particles from a single galaxy, and plan to develop tools with which to discriminate these streams from the the broader ICL distribution, since the particles of the stream should be clustered in phase space. Not only could we measure the evolution and lifetimes of these streams, but could also attempt to use them to trace out the orbits of their parent galaxies within the cluster Line-of-Sight Velocity Distribution Another technique with which we will study the phase space structure of the ICL is by measuring the velocity distribution of particles along individual lines of sight through the cluster. The first step in the analysis of the velocity distributions will be to develop tests for the presence of sub-structure, building on the work of Harding et al. (2001). Additionally, we can compare the velocity mean and dispersion of ICL structures to the velocity field of the cluster galaxies and the underlying dark matter, as well as to that
4 4 predicted for a virialized ICL population. These measurements will not only give us information on the origins and evolution of the ICL structures, but also allow us to relate the ICL to the dynamical state of the cluster as a whole. We can also use this data to investigate the possibility of using the ICL as an estimator of the cluster virial mass, with which to complement other mass estimation methods, such as galaxy velocity dispersion or X-ray gas temperatures. Observations of ICPNe are a potentially unique tool for mass estimation because they provide a very large number of independent kinematic tracers (Ford 2002; Romanowsky 2006a). For example, using the scaling between number of observed PNe and luminosity calculated for the Virgo cluster ICL by Durrell et al. (2002), the simulated clusters from Paper I would contain as many as 4300 observable ICPNe Relating the Simulations to Observations Observations of ICL kinematics are limited to line-of-sight velocities of ICPNe, which sample only a very small fraction of ICL stellar population. In order to make our observations of the simulations more directly applicable to actual astronomical observations, we can use the planetary nebulae luminosity function (PNLF; Durrell et al. 2002), along with our surface brightness maps, to normalize the number of ICL particles to the number of ICPNe which we would expect to observe. Thus we can sample the velocity distribution of the cluster along specific lines of sight in order to make our measurements directly comparable to observations of ICPNe. In order to further relate our simulations to current ICPNe observations, we will investigate the effects of limited areal coverage on our estimates of cluster properties, in order to determine optimal observational coverage needed in order to study real clusters. A related question which we will also seek to answer is how many ICPNe velocities are needed to fully sample the phase space distribution of the cluster. This has important implications for determining the optimal strategies of observational studies of clusters, since the number of ICPNe observed is directly related to the limiting magnitude of the survey, i.e. the number of observed PNe increases as the limiting magnitude of the survey increases, according to the PNLF Summary Recent measurements of the line-of-sight velocities of ICPNe provide a unique new tool for measuring the kinematic structure of the ICL. Using the cluster simulations presented in Paper I, we can attain a better understanding of how these observations can be used to identify phase-space substructure in the ICL. We will attempt to use this substructure to probe the dynamical history and relaxation state of the cluster, including tracing the orbits of individual galaxies and measuring the cluster mass distribution. Finally, we will be able to influence future observational strategies by determining the optimal areal coverage and depth of observations needed to provide the number of planetary nebulae necessary to fully describe the phase space distribution of the ICL.
5 5 3. Comparison of ICL Measurement Methodologies 3.1. Introduction A major issue which has arisen as the quantitative study of ICL has evolved is that there is no definitive definition of what exactly ICL is and how it should be measured. Perhaps the most physically appealing definition of ICL relates to its characteristic energy: ICL consists of stars which are bound to the gravitational potential of the cluster as a whole, but to no particular galaxy in the cluster. While this method of ICL identification has been used in several theoretical studies (Murante et al. 2004; Willman et al. 2004; Sommer-Larsen et al. 2005; Sommer-Larsen 2006), it requires not only six-dimensional phase space data for each ICL stellar tracer, but the detailed gravitational potential of the cluster, neither of which is observationally accessible. Most observational treatments use the surface brightness distribution of the cluster to define ICL. In rich clusters of galaxies, especially those dominated by a central cd galaxy, a common technique is to fit and subtract surface brightness profiles to the galaxies, with the residual luminosity taken to be the ICL (e.g. Vilchez-Gomez et al. 1994; Gonzalez et al. 2000; Feldmeier et al. 2002). However, different researchers have devised many different schemes with which to perform this galaxy subtraction, meaning that this technique does not yield a unique separation between galactic and ICL luminosity. A more welldefined definition of ICL that has been used is to separate ICL from galaxies using a surface brightness limit (Feldmeier et al. 2004; Paper I). Thus, all luminosity brighter than the surface brightness limit is classified as galactic, and all detected luminosity below the limit is the ICL. While a well-defined observable, this definition remains overly simplistic. The chosen chosen surface brightness limit is essentially arbitrary, and it is quite unlikely that a single surface brightness limit would be equally applicable to all clusters in all evolutionary stages. Yet another definition of ICL that has been used in the literature discriminates between galaxies and ICL based on their observable kinematic properties. As discussed in 2, Arnaboli et al. (2004) were able to distinguish ICPNe from galactic PNe projected onto the same line of sight by selecting ICPNe as having velocities inconsistent with that of the bound galaxy. Uniquely discriminating ICL from galactic luminosity projected onto the same line of sight is clearly impossible from surface brightness data alone. However, the one-dimensional velocity information available from ICPNe is not sufficient to determine the binding energy of the objects. Additionally, measuring the kinematics of ICPNe on large scales is a quite difficult, observationally intensive task, and will not be possible beyond clusters in the local universe. As the number of clusters studied for ICL continues to climb, the need to compare data sets and the difficulty in doing so grows correspondingly. We thus propose to undertake a systematic study of the various definitions of ICL in order to better understand how each relates to the others. Using the simulated clusters presented in Paper I, we will measure the ICL using each of the methods described above, and possibly new methods as well. The goal is to better understand the characteristics of the stellar populations measured by each of the methods, allowing us to better understand exactly what each definition is measuring. Furthermore, we will be able to make observational and simulation data measuring ICL using these varying
6 6 methods more directly comparable, eliminating much of the current uncertainty arising from the diverse array of measurement techniques currently in use Measuring ICL Unbound Particles The most physically meaningful definition of ICL is to classify it as stars which are not gravitationally bound to any individual cluster galaxy. Because stars are initially formed bound to their parent galaxies, and processes internal to the galaxies capable of ejecting stars are rare (e.g. Holley-Bockelmann et al. 2005), the vast majority of unbound stars within the cluster must have been stripped from their parent galaxies by interaction effects occurring as a result of the cluster environment. In this way, ICL is a unique product of the cluster environment, providing insight into how this environment effects the evolution of the galaxies within it. Unfortunately, the binding energy of individual stellar tracers is not observationally feasible, as discussed above. In N-body simulations, however, both complete phase space data data for all particles, and the detailed gravitational potential are readily available. Determining the gravitational potential will require specialized tools, such as the program SKID 1. SKID requires the input of several free parameters (most notably, the linking length used to aggregate particles) in order to function properly, and we will need to perform a series of focused tests in order to optimize these parameters. Such tests will consist primarily of assuring that SKID obtains the correct results in simple test situations, such as a fully bound isolated galaxy, two separate nearby galaxies, galaxies of both high and low mass and physical size, etc Surface Brightness In Paper I we created surface brightness maps of our clusters, analogous to broadband imaging, and defined ICL as all luminosity at surface brightness fainter than 26.5 mag arcsec 2 in the V -band, in order to make our definition fully observationally tractable. While informed by a qualitative inspection of the ICL morphology, the choice of limiting surface brightness was essentially arbitrary, reflecting our particular bias toward expected properties of the ICL. However, using the data on particle binding energies described above, we will be able to re-assess our choice of limiting surface brightness and attempt to relate the observable quantity surface brightness to the unobservable binding energy. For instance, we will be able to determine the surface brightness limit which best separates bound from unbound particles by measuring the fraction of unbound particles as a function of surface brightness or by finding the surface brightness limit which gives the same ICL fraction as the binding energy definition. Additionally, we will be able to see how these quantities change as the cluster evolves in order to determine how the dynamical state of the cluster affects 1
7 7 the relationship between binding energy and surface brightness. Using the same surface brightness maps from Paper I, we can also use a galaxy profile subtraction technique to measure the ICL content of our clusters. The exact fitting procedure to be used is still to be determined, but will most likely be based on fitting r 1/4 profiles to the large elliptical galaxies in the cluster and exponential profiles to the disk galaxies.. A key feature of this analysis will be to use only the 2-dimensional surface brightness distributions, exactly analogous to observational data. Once again, we will be interested in determining how well the ICL distribution obtained from such a technique is able to match the distribution of unbound stars and how the measured ICL fractions compare Line-of-Sight Velocities The final method of ICL detection we will explore is using the line-of-sight velocities of ICPNe to separate galactic luminosity from ICL. This analysis will be highly informed by the results of the ICPNe analysis described in 2. One of our main priorities will be to determine how to use line-of-sight velocities in order to distinguish bound from unbound ICPNe. Arnaboli et al. (2004) found PNe with velocities markedly distinct from that of any nearby cluster galaxy and classified these as ICPNe, while those with velocities similar to galaxies velocities were considered galactic. We would like to quantify how well such procedures work by finding false positive and negative rates. Additionally, we will attempt to develop more refined tools which utilize the full 3-dimensional data available to distinguish bound and unbound particles. One possible method includes using the available incomplete phase space data for each particle to determine the probability that the particle is bound. A novel method for determining the boundary between galactic and intracluster luminosity comes from the preliminary results of the velocity dispersion maps described in 2. This suggests that galaxies embedded in a diffuse ICL halo show a characteristic velocity dispersion profile. That is, within a few effective radii from the galaxy s center, the luminosity of the galaxy dominates that of the ICL, thus the velocity distribution is also dominated by the galaxy s characteristic declining velocity dispersion. However, at the outskirts of the galaxy, the ICL luminosity becomes comparable to the galaxy s, and the velocity distribution becomes dominated by the higher velocity dispersion ICL. A similar velocity dispersion profile was found in the globular cluster systems of elliptical galaxies at the center of massive groups in the local universe by Romanoswky (2006b). This transition from galactic to ICL velocity distribution could potentially be a useful way of separating galaxies from ICL, but much further testing is needed Summary While currently there are a many different functional definitions of ICL in use, there is very little understanding about how these definitions relate to one another. Theoretical studies tend to focus on using binding energy arguments to define ICL. However, this is unobservable in practice, so observational studies rely on the surface brightness distribution of the cluster, or on the line-of-sight velocities of ICPNe to deter-
8 8 mine the ICL component. With our strong focus on observable quantities in our simulations, including the surface brightness maps from Paper I and the ICPNe measurements from 2, we are well placed to bridge this gap in understanding between different methods, allowing a much more comprehensive comparison of the available data. Adami, C., et al. 2005, A&A, 429, 39 REFERENCES Aguerri, J. A. L., Castro-Rodríguez, N., Napolitano, N., Arnaboldi, M., & Gerhard, O. 2006, A&A, 457, 771 Arnaboldi, M., Gerhard, O., Aguerri, J. A. L., Freeman, K. C., Napolitano, N. R., Okamura, S., & Yasuda, N. 2004, ApJ, 614, L33 Binggeli, B. 1999, LNP Vol. 530: The Radio Galaxy Messier 87, 530, 9 Ciardullo, R., Mihos, J. C., Feldmeier, J. J., Durrell, P. R., & Sigurdsson, S. 2004, IAU Symposium, 217, 88 Da Rocha, C., & Mendes de Oliveira, C. 2005, MNRAS, 364, 1069 Durrell, P. R., Ciardullo, R., Feldmeier, J. J., Jacoby, G. H., & Sigurdsson, S. 2002, ApJ, 570, 119 Feldmeier, J. J., Mihos, J. C., Morrison, H. L., Harding, P., Kaib, N., & Dubinski, J. 2004, ApJ, 609, 617 Feldmeier, J. J., Mihos, J. C., Morrison, H. L., Rodney, S. A., & Harding, P. 2002, ApJ, 575, 779 Ford, H., Peng, E., & Freeman, K. 2002, ASP Conf. Ser. 273: The Dynamics, Structure & History of Galaxies: A Workshop in Honour of Professor Ken Freeman, 273, 41 Gal-Yam, A., Maoz, D., Guhathakurta, P., & Filippenko, A. V. 2003, AJ, 125, 1087 Gerhard, O., Arnaboldi, M., Freeman, K. C., Kashikawa, N., Okamura, S., & Yasuda, N. 2005, ApJ, 621, L93 Gnedin, O. Y. 2003, ApJ, 582, 141 Gonzalez, A. H., Zabludoff, A. I., Zaritsky, D., & Dalcanton, J. J. 2000, ApJ, 536, 561 Harding, P., Morrison, H. L., Olszewski, E. W., Arabadjis, J., Mateo, M., Dohm-Palmer, R. C., Freeman, K. C., & Norris, J. E. 2001, AJ, 122, 1397 Holley-Bockelmann, K., Sigurdsson, S., Mihos, J. C., Feldmeier, J. J., Ciardullo, R., & McBride, C. 2005, astro-ph/ Liu, Y., Zhou, X., Ma, J., Wu, H., Yang, Y., Li, J., & Chen, J. 2005, AJ, 129, 2628
9 9 Mihos, J. C., Harding, P., Feldmeier, J., & Morrison, H. 2005, ApJ, 631, L41 Moore, B., Lake, G., & Katz, N. 1998, ApJ, 495, 139 Murante, G., et al. 2004, ApJ, 607, L83 Napolitano, N. R., et al. 2003, ApJ, 594, 172 Romanowsky, A. J. 2006a, astro-ph/ Romanowsky, A. J. 2006b, astro-ph/ Rudick, C. S., Mihos, J. C., & McBride, C. 2006, ApJ, 648, 936 Sommer-Larsen, J. 2006, MNRAS, 369, 958 Sommer-Larsen, J., Romeo, A. D., & Portinari, L. 2005, MNRAS, 357, 478 Taylor, V. A., Jansen, R. A., & Windhorst, R. A. 2004, PASP, 116, 762 Uson, J. M., Boughn, S. P., & Kuhn, J. R. 1991, ApJ, 369, 46 Vila-Costas, M. B., & Edmunds, M. G. 1992, MNRAS, 259, 121 Vilchez-Gomez, R., Pello, R., & Sanahuja, B. 1994, A&A, 283, 37 Wechsler, R. H., Bullock, J. S., Primack, J. R., Kravtsov, A. V., & Dekel, A. 2002, ApJ, 568, 52 Willman, B., Governato, F., Wadsley, J., & Quinn, T. 2004, MNRAS, 355, 159 Zibetti, S., White, S. D. M., Schneider, D. P., & Brinkmann, J. 2005, MNRAS, 358, 949 Zwicky, F. 1951, PASP, 63, 61 This preprint was prepared with the AAS L A TEX macros v5.2.
10 10 Fig. 1. The surface brightness distribution of one of our simulated clusters, first presented in Paper I as cluster C2, at z=0. The colorbar at the bottom shows the surface brightness scale in mag/arcsec 2 in the V band. Fig. 2. The mean velocity distribution of the same cluster as shown in Fig. 1. The colorbar at the bottom shows the velocity scale in km/s.
11 11 Fig. 3. The velocity dispersion distribution of the same cluster as shown in Fig. 1. The colorbar at the bottom shows the velocity dispersion scale in km/s.
The Formation and Evolution of Intracluster Light
The Formation and Evolution of Intracluster Light Craig S. Rudick, J. Christopher Mihos, and Cameron McBride 1 craig@fafnir.astr.cwru.edu, mihos@case.edu, ckm8@pitt.edu Department of Astronomy, Case Western
More informationTHE FORMATION AND EVOLUTION OF INTRACLUSTER LIGHT
DRAFT VERSION MAY 16, 2006 Preprint typeset using LATEX style emulateapj v. 11/26/04 THE FORMATION AND EVOLUTION OF INTRACLUSTER LIGHT CRAIG S. RUDICK, J. CHRISTOPHER MIHOS, AND CAMERON MCBRIDE 1 Department
More informationThe kinematics of the extreme outer halo of. M87 as revealed by Planetary Nebulae. A.Longobardi M.Arnaboldi O.Gerhard. Garching 2015, 26th Feb.
The kinematics of the extreme outer halo of A. M.Arnaboldi O.Gerhard Max-Planck-Institut für extraterrestrische Physik Garching 2015, 26th Feb. Outer regions of galaxies and structure formation Formation
More informationarxiv:astro-ph/ v1 2 Mar 2006
The Astrophysical Journal, in press Merging of Elliptical Galaxies as Possible Origin of the Intergalactic Stellar Population arxiv:astro-ph/0603054v1 2 Mar 2006 Letizia Stanghellini National Optical Astronomy
More informationThe Virgo cd galaxy M87 and its environment as revealed by Planetary Nebulae
The Virgo cd galaxy M87 and its environment as A. M.Arnaboldi O.Gerhard C.J.Mihos Max-Planck-Institut für extraterrestrische Physik IAU XXIX GA 2015 Division J Outer regions of galaxies and structure formation
More informationarxiv:astro-ph/ v1 30 Nov 2004
Probing Halos with PNe: Mass and Angular Momentum in Early-Type Galaxies Aaron J. Romanowsky arxiv:astro-ph/0411797v1 30 Nov 2004 School of Physics and Astronomy, University of Nottingham, University Park,
More informationThe importance of mergers for the origin of intracluster stars in cosmological simulations of galaxy clusters
Mon. Not. R. Astron. Soc. 377, 2 16 (27) doi:1.1111/j.1365-2966.27.11568.x The importance of mergers for the origin of intracluster stars in cosmological simulations of galaxy clusters Giuseppe Murante,
More informationNMAGIC Made-to-Measure Modeling of Elliptical Galaxies NMAGIC - 2 M2M
NMAGIC Made-to-Measure Modeling of Elliptical Galaxies Ortwin Gerhard, MPE, Garching gerhard@mpe.mpg.de I. Made-to-measure dynamical modeling with NMAGIC II Elliptical galaxy halo kinematics with planetary
More informationarxiv:astro-ph/ v1 14 Oct 2003
**TITLE** ASP Conference Series, Vol. **VOLUME***, **YEAR OF PUBLICATION** **NAMES OF EDITORS** Galaxy threshing and the origin of intracluster stellar objects arxiv:astro-ph/0310350v1 14 Oct 2003 Kenji
More informationGalaxy clusters. Dept. of Physics of Complex Systems April 6, 2018
Galaxy clusters László Dobos Dept. of Physics of Complex Systems dobos@complex.elte.hu É 5.60 April 6, 2018 Satellite galaxies Large galaxies are surrounded by orbiting dwarfs approx. 14-16 satellites
More informationStellar Orbits and Angular Momentum in Early-Type Galaxy Halos Ortwin Gerhard, MPE, Garching
Stellar Orbits and Angular Momentum in Early-Type Galaxy Halos Ortwin Gerhard, MPE, Garching gerhard@mpe.mpg.de 1. Preamble Arnaboldi et al 2013 2. Predictions: ETG halos in cosmological simulations 3.
More informationLecture Three: Observed Properties of Galaxies, contd.! Hubble Sequence. Environment! Globular Clusters in Milky Way. kpc
Hubble Sequence Lecture Three: Fundamental difference between Elliptical galaxies and galaxies with disks, and variations of disk type & importance of bulges Observed Properties of Galaxies, contd.! Monday
More informationarxiv:astro-ph/ v1 24 Jun 2005
The Survival of Planetary Nebulae in the Intracluster Medium Eva Villaver 1 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA; villaver@stsci.edu arxiv:astro-ph/0506612v1
More informationarxiv:astro-ph/ v1 20 Mar 2007
Planetary Nebulae in our Galaxy and Beyond Proceedings IAU Symposium No. 234, 2006 M. Barlow, R.H. Mendez, eds. c 2006 International Astronomical Union DOI: 00.0000/X000000000000000X Planetary Nebulae
More informationarxiv: v1 [astro-ph.ga] 7 Oct 2015
The General Assembly of Galaxy Halos Proceedings IAU Symposium No. 317, 2015 c 2015 International Astronomical Union A.Bragaglia, M. Arnaboldi, M. Rejkuba, & D. Romano, eds. DOI: 00.0000/X000000000000000X
More informationA Panoramic View of Globular Cluster Systems in the Virgo and Coma Clusters
A Panoramic View of Globular Cluster Systems in the Virgo and Coma Clusters Eric Peng Peking University Kavli Institute for Astronomy and Astrophysics Globular Cluster Systems z=12 GCs form early in the
More informationThe cosmic distance scale
The cosmic distance scale Distance information is often crucial to understand the physics of astrophysical objects. This requires knowing the basic properties of such an object, like its size, its environment,
More informationIntracluster light in individual moderate redshift (0.02 < z < 0.31) clusters
Intracluster light in individual moderate redshift (0.02 < z < 0.31) clusters John Feldmeier (YSU) A1914 (Feldmeier et al. 2004) A 1651 (Gonzalez et al. 2000) A 4010 (Krick et al. 2008) Collaborators:
More informationLecture Three: Observed Properties of Galaxies, contd. Longair, chapter 3 + literature. Monday 18th Feb
Lecture Three: Observed Properties of Galaxies, contd. Longair, chapter 3 + literature Monday 18th Feb 1 The Hertzsprung-Russell Diagram magnitude colour LOW MASS STARS LIVE A VERY VERY LONG TIME! 2 The
More informationUsing Globular Clusters to. Study Elliptical Galaxies. The View Isn t Bad... Omega Centauri. Terry Bridges Australian Gemini Office M13
Using Globular Clusters to Omega Centauri Study Elliptical Galaxies Terry Bridges Australian Gemini Office 10,000 1,000,000 stars up to 1000 stars/pc3 typical sizes ~10 parsec Mike Beasley (IAC, Tenerife)
More informationarxiv: v1 [astro-ph] 31 Jul 2007
Mon. Not. R. Astron. Soc. 000, 1?? (1994) Printed 1 February 8 (MN LATEX style file v1.4) Origin of lower velocity dispersions of ultra-compact dwarf galaxy populations in clusters of galaxies K. Bekki
More informationHI as a probe for dwarf galaxy evolution in different environments: Voids to clusters
HI as a probe for dwarf galaxy evolution in different environments: Voids to clusters Sushma Kurapati Collaborators: Jayaram N Chengalur, NCRA, India Simon Pustilnik, SAO RAS, Russia 2017 PHISCC Workshop
More informationThe dark matter crisis
The dark matter crisis Ben Moore Department of Physics, Durham University, UK. arxiv:astro-ph/0103100 v2 8 Mar 2001 Abstract I explore several possible solutions to the missing satellites problem that
More informationDark Matter Detection Using Pulsar Timing
Dark Matter Detection Using Pulsar Timing ABSTRACT An observation program for detecting and studying dark matter subhalos in our galaxy is propsed. The gravitational field of a massive object distorts
More informationThe Star Clusters of the Magellanic Clouds
The Dance of Stars MODEST-14 The Star Clusters of the Magellanic Clouds Eva K. Grebel Astronomisches Rechen-Institut Zentrum für Astronomie der Universität Heidelberg Star Clusters in the Magellanic Clouds!
More informationarxiv: v1 [astro-ph.co] 20 Jan 2010
Highlights of Astronomy, Volume 15 XXVIIth IAU General Assembly, August 2009 Ian F Corbett, ed. c 2009 International Astronomical Union DOI: 00.0000/X000000000000000X Diffuse Light in Galaxy Clusters Magda
More informationGlobular Clusters in Massive Galaxies
Globular Clusters in Massive Galaxies Patrick Durrell (Youngstown State University) + Pat Côté, John Blakeslee, Laura Ferrarese (Herzberg-Victoria), Eric Peng (Peking Univ) Chris Mihos (CWRU) + NGVS Team
More informationPart two of a year-long introduction to astrophysics:
ASTR 3830 Astrophysics 2 - Galactic and Extragalactic Phil Armitage office: JILA tower A909 email: pja@jilau1.colorado.edu Spitzer Space telescope image of M81 Part two of a year-long introduction to astrophysics:
More informationSurface Brightness of Spiral Galaxies
Surface Brightness of Spiral Galaxies M104: SA N4535: SAB LMC: dwarf irregular,barred Normal 1/4-law+exp fits An example of surface brightness profile. The top curve is the sum of exp disk+1/4-bulge. The
More informationGaia Revue des Exigences préliminaires 1
Gaia Revue des Exigences préliminaires 1 Global top questions 1. Which stars form and have been formed where? - Star formation history of the inner disk - Location and number of spiral arms - Extent of
More informationAstr 5465 Feb. 5, 2018 Kinematics of Nearby Stars
Astr 5465 Feb. 5, 2018 Kinematics of Nearby Stars Properties of Nearby Stars Most in orbit with the Sun around Galactic Center Stellar Kinematics Reveal Groups of Stars with Common Space Motion (Moving
More informationMapping Dark Matter in Galaxy Clusters: Gravitational Lensing & Numerical Simulations
Mapping Dark Matter in Galaxy Clusters: Gravitational Lensing & Numerical Simulations Marceau Limousin Laboratoire d Astrophysique de Toulouse-Tarbes, Université de Toulouse, CNRS 57 avenue d Azereix,
More informationThe outskirt of the Virgo cd galaxy M87 as revealed by Planetary Nebulae
Max-Planck-Institut für extraterrestrische Physik EWASS 2015, Sp16 Outer regions of galaxies and structure formation Formation of ICL and extended halos around BCGs closely related to the morphological
More informationPlanetary Nebulae beyond the Milky Way historical overview
Planetary Nebulae beyond the Milky Way historical overview M. J. Barlow Dept. of Physics & Astronomy University College London Outline (a) Surveys for planetary nebulae in other galaxies, PN luminosity
More informationGlobular Cluster Systems as Tracers of Galaxy Formation and Evolution
Globular Cluster Systems as Tracers of Galaxy Formation and Evolution Clues from MOS Surveys Mihos+2005 Rubén Sánchez-Janssen Plaskett Fellow NRC Herzberg Institute of Astrophysics S/C de la Palma 2015-03-03
More informationLuminosity Functions of Planetary Nebulae & Globular Clusters. By Azmain Nisak ASTR 8400
Luminosity Functions of Planetary Nebulae & Globular Clusters By Azmain Nisak ASTR 8400 Calculating Distance! m = apparent magnitude! M = absolute magnitude! r = distance in pc GLOBULAR CLUSTERS AS DISTANCE
More informationStudying Galaxy Formation with Hubble s Successor
Hubble s Science Legacy: Future Optical-Ultraviolet Astronomy from Space ASP Conference Series, Vol. 000, 2002 K.R. Sembach, J.C. Blades, G.D. Illingworth, R.C. Kennicutt Studying Galaxy Formation with
More informationarxiv: v1 [astro-ph.co] 26 Aug 2009
Astronomy & Astrophysics manuscript no. virgo MAR referee c ESO 2018 June 12, 2018 Intracluster Light in the Virgo Cluster: Large Scale Distribution N. Castro-Rodriguéz 1, M. Arnaboldi 2,3, J. A. L. Aguerri
More informationClusters and Groups of Galaxies
Clusters and Groups of Galaxies Groups and clusters The Local Group Clusters: spatial distribution and dynamics Clusters: other components Clusters versus groups Morphology versus density Groups and Clusters
More informationPractice Problem!! Assuming a uniform protogalactic (H and He only) cloud with a virial temperature of 10 6 K and a density of 0.
Practice Problem Assuming a uniform protogalactic (H and He only) cloud with a virial temperature of 10 6 K and a density of 0.05 cm -3 (a) estimate the minimum mass that could collapse, (b) what is the
More informationStarbursts, AGN, and Interacting Galaxies 1 ST READER: ROBERT GLEISINGER 2 ND READER: WOLFGANG KLASSEN
Starbursts, AGN, and Interacting Galaxies 1 ST READER: ROBERT GLEISINGER 2 ND READER: WOLFGANG KLASSEN Galaxy Interactions Galaxy Interactions Major and Minor Major interactions are interactions in which
More informationStellar Populations in the Local Group
Stellar Populations in the Local Group Recall what we ve learned from the Milky Way: Age and metallicity tend to be correlated: older -> lower heavy element content younger -> greater heavy element content
More informationA new mechanism for the formation of PRGs
A new mechanism for the formation of PRGs Spavone Marilena (INAF-OAC) Iodice Enrica (INAF-OAC), Arnaboldi Magda (ESO-Garching), Longo Giuseppe (Università Federico II ), Gerhard Ortwin (MPE-Garching).
More informationA MUSE view of cd galaxy NGC 3311
A MUSE view of cd galaxy NGC 3311 C. E. Barbosa 1, M. Arnaboldi 2, L. Coccato 2, O. Gerhard 3, C. Mendes de Oliveira 1, M. Hilker 2, T. Richtler 4 1 Universidade de São Paulo, São Paulo, Brazil 2 European
More informationPhys/Astro 689: Lecture 8. Angular Momentum & the Cusp/Core Problem
Phys/Astro 689: Lecture 8 Angular Momentum & the Cusp/Core Problem Summary to Date We first learned how to construct the Power Spectrum with CDM+baryons. Found CDM agrees with the observed Power Spectrum
More informationAn Introduction to Galaxies and Cosmology. Jun 29, 2005 Chap.2.1~2.3
An Introduction to Galaxies and Cosmology Jun 29, 2005 Chap.2.1~2.3 2.1 Introduction external galaxies normal galaxies - majority active galaxies - 2% high luminosity (non-stellar origin) variability
More informationThe Milky Way and Near-Field Cosmology
The Milky Way and Near-Field Cosmology Kathryn V Johnston (Columbia University) Collaborators (theorists): James S Bullock (Irvine), Andreea Font (Durham), Brant Robertson (Chicago), Sanjib Sharma (Columbia),
More informationarxiv:astro-ph/ v2 16 Jan 2006
Accepted for publication in ApJ Letters Spatial Distribution of Faint Fuzzy Star Clusters in NGC 5195 Narae Hwang and Myung Gyoon Lee arxiv:astro-ph/0601280v2 16 Jan 2006 Astronomy Program, SEES, Seoul
More informationThe power of chemical tagging for studying Galactic evolution
for studying Galactic evolution RSAA, Australian National University, Cotter Rd, Weston Creek, ACT, 2611, Australia E-mail: ewylie@mso.anu.edu.au Kenneth Freeman RSAA, Australian National University, Cotter
More informationSimulations Applied to the Bright SHARC XCLF: Results and Implications
The Evolution of Galaxies on Cosmological Timescales ASP Conference Series, Vol. 3 10 8, 1999 J. E. Beckman, and T. J. Mahoney, eds. Simulations Applied to the Bright SHARC XCLF: Results and Implications
More informationarxiv: v1 [astro-ph.ga] 2 Feb 2016
Preprint 14 May 2018 Compiled using MNRAS LATEX style file v3.0 arxiv:1602.01105v1 [astro-ph.ga] 2 Feb 2016 The SLUGGS Survey: globular clusters and the dark matter content of early-type galaxies Duncan
More informationarxiv: v1 [astro-ph.ga] 17 Jun 2009
Discovery of a New, Polar-Orbiting Debris Stream in the Milky Way Stellar Halo Heidi Jo Newberg 1, Brian Yanny 2, & Benjamin A. Willett 1 arxiv:0906.3291v1 [astro-ph.ga] 17 Jun 2009 ABSTRACT We show that
More informationTHE VIRGO CLUSTER: GALAXY EVOLUTION IN ACTION
Proceedings of the Fall 2007 Astronomy 233 Symposium on THE VIRGO CLUSTER: GALAXY EVOLUTION IN ACTION Jennifer Burt, Jessie DeGrado, Stephen Demjanenko, Jared Feldman, Samuel Johnson Stoever, Jae Hwan
More informationNumerical Cosmology & Galaxy Formation
Numerical Cosmology & Galaxy Formation Lecture 13: Example simulations Isolated galaxies, mergers & zooms Benjamin Moster 1 Outline of the lecture course Lecture 1: Motivation & Historical Overview Lecture
More informationComa Cluster Matthew Colless. Encyclopedia of Astronomy & Astrophysics P. Murdin
eaa.iop.org DOI: 10.1888/0333750888/2600 Coma Cluster Matthew Colless From Encyclopedia of Astronomy & Astrophysics P. Murdin IOP Publishing Ltd 2006 ISBN: 0333750888 Institute of Physics Publishing Bristol
More informationarxiv:astro-ph/ v1 17 Aug 2001
HOW DID GLOBULAR CLUSTERS FORM? Sidney van den Bergh Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National arxiv:astro-ph/0108298v1 17 Aug 2001 Research Council of Canada, 5071
More informationNearby Galaxy Evolution with Deep Surveys: Studying galaxies at 1<D<100 Mpc. Eric Peng Peking University
Nearby Galaxy Evolution with Deep Surveys: Studying galaxies at 1
More informationThe Merger History of Massive Galaxies: Observations and Theory
The Merger History of Massive Galaxies: Observations and Theory Christopher J. Conselice (University of Nottingham) Kuala Lumpur 2009 How/when do galaxies form/evolve? Some questions a. Do galaxies evolve
More informationASTR 200 : Lecture 25. Galaxies: internal and cluster dynamics
ASTR 200 : Lecture 25 Galaxies: internal and cluster dynamics 1 Galaxy interactions Isolated galaxies are often spirals One can find small galaxy `groups' (like the Local group) with only a few large spiral
More informationThe physical origin of stellar envelopes around globular clusters
The physical origin of stellar envelopes around globular clusters Phil Breen University of Edinburgh in collaboration with A. L. Varri, J. Peñarrubia and D. C. Heggie Current observational evidence Example:
More informationAstro2010 Science White Paper: The Galactic Neighborhood (GAN)
Astro2010 Science White Paper: The Galactic Neighborhood (GAN) Thomas M. Brown (tbrown@stsci.edu) and Marc Postman (postman@stsci.edu) Space Telescope Science Institute Daniela Calzetti (calzetti@astro.umass.edu)
More informationTHE BOLSHOI COSMOLOGICAL SIMULATIONS AND THEIR IMPLICATIONS
GALAXY FORMATION - Durham -18 July 2011 THE BOLSHOI COSMOLOGICAL SIMULATIONS AND THEIR IMPLICATIONS JOEL PRIMACK, UCSC ΛCDM Cosmological Parameters for Bolshoi and BigBolshoi Halo Mass Function is 10x
More informationThis week at Astro 3303
This week at Astro 3303 HW #8-10 deal with your final project! (HW#8 is posted already) The project counts 20% of the grade and is expected to be a significant piece of work. HW#8 for next Wed: prepare
More informationUpcoming class schedule
Upcoming class schedule Thursday March 15 2pm AGN evolution (Amy Barger) th Monday March 19 Project Presentation (Brad) nd Thursday March 22 postponed to make up after spring break.. Spring break March
More informationGalaxy dynamics with the Planetary Nebula Spectrograph
Mem. S.A.It. Suppl. Vol. 5, 255 c SAIt 2004 Memorie della Supplementi Galaxy dynamics with the Planetary Nebula Spectrograph N.R. Napolitano 1, A.J. Romanowsky 2, N.G. Douglas 1, M. Capaccioli 3, M. Arnaboldi
More informationThe Combined effects of ram pressure stripping, and tidal influences on Virgo cluster dwarf galaxies, using N body/ SPH simulation
The Combined effects of ram pressure stripping, and tidal influences on Virgo cluster dwarf galaxies, using N body/ SPH simulation Author: Rory Smith, Cardiff University Collaborators: Jonathon Davies,
More informationarxiv: v1 [astro-ph.sr] 23 Jun 2009
COMPARING SYMBIOTIC NEBULAE AND PLANETARY NEBULAE LUMINOSITY FUNCTIONS Adam Frankowski & Noam Soker arxiv:0906.4356v1 [astro-ph.sr] 23 Jun 2009 Department of Physics, Technion Israel Institute of Technology,
More informationInclination-Dependent Extinction Effects in Disk Galaxies in the Sloan Digital Sky Survey aa aa. A Senior Honors Thesis
1 Inclination-Dependent Extinction Effects in Disk Galaxies in the Sloan Digital Sky Survey aa aa aa aa A Senior Honors Thesis Presented in Partial Fulfillment of the Requirements for Graduation with Distinction
More informationSupernova Feedback in Low and High Mass Galaxies: Luke Hovey 10 December 2009
Supernova Feedback in Low and High Mass Galaxies: Luke Hovey 10 December 2009 Galactic Winds: Mathews, W. et al. 1971 Effects of Supernovae on the Early Evolution of Galaxies: Larson, R. 1974 The origin
More informationarxiv:astro-ph/ v1 1 Feb 2000
Compact Stellar Systems in the Fornax Cluster: Super-massive Star Clusters or Extremely Compact Dwarf Galaxies? M. J. Drinkwater 1 J. B. Jones 2 M. D. Gregg 3 S. Phillipps 4 to appear in Publications of
More informationFermilab FERMILAB-Conf-00/339-A January 2001
Fermilab FERMILAB-Conf-00/339-A January 2001 **TITLE** ASP Conference Series, Vol. **VOLUME**, **PUBLICATION YEAR** **EDITORS** Precision Galactic Structure Stephen Kent Fermilab, P. O. Box 500, Batavia,
More informationarxiv:astro-ph/ v1 5 Jul 2006
THE DWARF SATELLITES OF M31 AND THE GALAXY Sidney van den Bergh Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 West Saanich Road, Victoria,
More informationMilky Way S&G Ch 2. Milky Way in near 1 IR H-W Rixhttp://online.kitp.ucsb.edu/online/galarcheo-c15/rix/
Why study the MW? its "easy" to study: big, bright, close Allows detailed studies of stellar kinematics, stellar evolution. star formation, direct detection of dark matter?? Milky Way S&G Ch 2 Problems
More informationPeculiar (Interacting) Galaxies
Peculiar (Interacting) Galaxies Not all galaxies fall on the Hubble sequence: many are peculiar! In 1966, Arp created an Atlas of Peculiar Galaxies based on pictures from the Palomar Sky Survey. In 1982,
More informationMERGERS OF GLOBULAR CLUSTERS
MERGERS OF GLOBULAR CLUSTERS SIDNEY VAN DEN BERGH Dominion Astrophysical Observatory 5071 West Saanich Road Victoria, British Columbia V8X 4M6, Canada vandenbergh@dao.nrc.ca Received: 1996 July 1 ; accepted:
More informationClicker Question: Galaxy Classification. What type of galaxy do we live in? The Variety of Galaxy Morphologies Another barred galaxy
Galaxies Galaxies First spiral nebula found in 1845 by the Earl of Rosse. Speculated it was beyond our Galaxy. 1920 - "Great Debate" between Shapley and Curtis on whether spiral nebulae were galaxies beyond
More informationarxiv:astro-ph/ v2 7 Oct 2004
Formation of ω Centauri by Tidal Stripping of a Dwarf Galaxy Makoto Ideta Astronomical Data Analysis Center, National Astronomical Observatory of Japan 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan arxiv:astro-ph/0408431v2
More informationarxiv:astro-ph/ v1 4 Apr 2006
Draft version February 5, 2008 Preprint typeset using L A TEX style emulateapj v. 6/22/04 THE EFFECT OF SUBSTRUCTURE ON MASS ESTIMATES OF GALAXIES Brian M. Yencho 1, Kathryn V. Johnston 1, James S. Bullock
More informationView of the Galaxy from within. Lecture 12: Galaxies. Comparison to an external disk galaxy. Where do we lie in our Galaxy?
Lecture 12: Galaxies View of the Galaxy from within The Milky Way galaxy Rotation curves and dark matter External galaxies and the Hubble classification scheme Plotting the sky brightness in galactic coordinates,
More informationLecture Outlines. Chapter 25. Astronomy Today 7th Edition Chaisson/McMillan Pearson Education, Inc.
Lecture Outlines Chapter 25 Astronomy Today 7th Edition Chaisson/McMillan Chapter 25 Galaxies and Dark Matter Units of Chapter 25 25.1 Dark Matter in the Universe 25.2 Galaxy Collisions 25.3 Galaxy Formation
More informationRelics of the hierarchical assembly of the Milky Way
Mem. S.A.It. Suppl. Vol. 5, 83 c SAIt 2004 Memorie della Supplementi Relics of the hierarchical assembly of the Milky Way M. Bellazzini INAF - Osservatorio Astronomico di Bologna, via Ranzani 1, 40127
More informationA galaxy is a self-gravitating system composed of an interstellar medium, stars, and dark matter.
Chapter 1 Introduction 1.1 What is a Galaxy? It s surprisingly difficult to answer the question what is a galaxy? Many astronomers seem content to say I know one when I see one. But one possible definition
More informationThe origin of lopsidedness in galaxies
The Galaxy Disk in Cosmological Context Proceedings IAU Symposium No. xxx, 2008 c 2008 International Astronomical Union J. Andersen (Chief Editor), J. Bland-Hawthorn & B. Nordström, eds. The origin of
More informationarxiv: v2 [astro-ph] 14 Apr 2009
Mon. Not. R. Astron. Soc.,?? (5) Printed 4 April 9 (MN LATEX style file v.) The total mass and dark halo properties of the Small Magellanic Cloud arxiv:87.v [astro-ph] 4 Apr 9 Kenji Bekki and Snežana Stanimirović
More informationarxiv: v1 [astro-ph.co] 12 May 2009
Astronomy & Astrophysics manuscript no. 1532 c ESO 2018 March 12, 2018 arxiv:0905.1958v1 [astro-ph.co] 12 May 2009 The Edge of the M87 Halo and the Kinematics of the Diffuse Light in the Virgo Cluster
More informationSearch for streams in thick disk and halo of the Milky Way
Journal of Physics: Conference Series PAPER OPEN ACCESS Search for streams in thick disk and halo of the Milky Way To cite this article: Dian Puspita Triani and M Ikbal Arifyanto 2016 J. Phys.: Conf. Ser.
More informationSurvey of Astrophysics A110
Goals: Galaxies To determine the types and distributions of galaxies? How do we measure the mass of galaxies and what comprises this mass? How do we measure distances to galaxies and what does this tell
More informationWeak Gravitational Lensing
Weak Gravitational Lensing Sofia Sivertsson October 2006 1 General properties of weak lensing. Gravitational lensing is due to the fact that light bends in a gravitational field, in the same fashion as
More informationarxiv: v1 [astro-ph] 10 May 2007
A Pair of Boötes: A New Milky Way Satellite S. M. Walsh 1, H. Jerjen 1, B. Willman 2 arxiv:0705.1378v1 [astro-ph] 10 May 2007 ABSTRACT As part of preparations for a southern sky search for faint Milky
More informationMapping the Galactic halo with main-sequence and RR Lyrae stars
EPJ Web of Conferences 19, 02002 (2012) DOI: 10.1051/epjconf/20121902002 C Owned by the authors, published by EDP Sciences, 2012 Mapping the Galactic halo with main-sequence and RR Lyrae stars B. Sesar
More informationLecture 15: Galaxy morphology and environment
GALAXIES 626 Lecture 15: Galaxy morphology and environment Why classify galaxies? The Hubble system gives us our basic description of galaxies. The sequence of galaxy types may reflect an underlying physical
More informationTrES Exoplanets and False Positives: Finding the Needle in the Haystack
Transiting Extrasolar Planets Workshop ASP Conference Series, Vol. 366, 2007 C. Afonso, D. Weldrake and Th. Henning TrES Exoplanets and False Positives: Finding the Needle in the Haystack F. T. O Donovan
More informationThe King's University College Astronomy 201 Mid-Term Exam Solutions
The King's University College Astronomy 201 Mid-Term Exam Solutions Instructions: The exam consists of two sections. Part A is 20 multiple choice questions - please record answers on the sheet provided.
More informationLecture Outlines. Chapter 23. Astronomy Today 8th Edition Chaisson/McMillan Pearson Education, Inc.
Lecture Outlines Chapter 23 Astronomy Today 8th Edition Chaisson/McMillan Chapter 23 The Milky Way Galaxy Units of Chapter 23 23.1 Our Parent Galaxy 23.2 Measuring the Milky Way Discovery 23-1 Early Computers
More informationDistinguishing between WDM and CDM by studying the gap power spectrum of stellar streams
Distinguishing between WDM and CDM by studying the gap power spectrum of stellar streams based on arxiv:1804.04384, JCAP 07(2018)061 Nilanjan Banik Leiden University/GRAPPA, University of Amsterdam In
More informationChapter 23 The Milky Way Galaxy Pearson Education, Inc.
Chapter 23 The Milky Way Galaxy The Milky Way is our own galaxy viewed from the inside. It is a vast collection of more than 200 billion stars, planets, nebulae, clusters, dust and gas. Our own sun and
More informationSpiral Structure. m ( Ω Ω gp ) = n κ. Closed orbits in non-inertial frames can explain the spiral pattern
Spiral Structure In the mid-1960s Lin and Shu proposed that the spiral structure is caused by long-lived quasistatic density waves The density would be higher by about 10% to 20% Stars, dust and gas clouds
More informationOverview of Dynamical Modeling. Glenn van de Ven
Overview of Dynamical Modeling Glenn van de Ven glenn@mpia.de 1 Why dynamical modeling? -- mass total mass stellar systems key is to their evolution compare luminous mass: constrain DM and/or IMF DM radial
More informationThis week at Astro Lecture 06, Sep 13, Pick up PE#6. Please turn in HW#2. HW#3 is posted
This week at Astro 3303 Lecture 06, Sep 13, 2017 Pick up PE#6 Please turn in HW#2 HW#3 is posted Today: Introduction to galaxy photometry Quantitative morphology Elliptical galaxies Reading: Continue reading
More informationMilky Way s Mass and Stellar Halo Velocity Dispersion Profiles
Milky Way s Mass and Stellar Halo Velocity Dispersion Profiles Shanghai Astronomical Observatory In collaboration with Juntai Shen, Xiang Xiang Xue, Chao Liu, Chris Flynn, Ling Zhu, Jie Wang Contents 1
More information