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Articles 31 - 60 of 79
Full-Text Articles in Physical Sciences and Mathematics
Entropy And State Visualization For Automation Design And Evaluation Prototyping Toolset, Rohit Deshmukh
Entropy And State Visualization For Automation Design And Evaluation Prototyping Toolset, Rohit Deshmukh
Master's Projects
Automation Design and Evaluation Prototyping Toolset (ADEPT) is a plugin developed on the Eclipse Rich Client Platform(RCP). ADEPT can be used by domain expert designers to create and modify testable prototypes. The aim of the project is to enhance ADEPT by adding dynamic visualizations to the ADEPT user interface. Three types of visualizations are implemented in this project. Table view is helpful to view the hierarchy and nesting of Logic Tables. The State visualization displays all the states in a selected Logic Table. Entropy visualization is a subset of State visualization and displays limited number of states having lowest Entropy …
Cloud Services For An Android Based Home Security System, Karthik Challa
Cloud Services For An Android Based Home Security System, Karthik Challa
Master's Projects
This report talks in detail about an android based application designed for a home security system. The home security system is a tablet device developed using the android framework. The home security system makes use of sensors and a central device to secure an area. Currently the devices are standalone and require the users to be physically present to operate the devices with no interaction possible between two different devices. The system is also limited by its computational resources and storage capacity. For this project, I have developed a cloud based client server architecture to address these limitations and also …
Analysis Of Parallel Montgomery Multiplication In Cuda, Yuheng Liu
Analysis Of Parallel Montgomery Multiplication In Cuda, Yuheng Liu
Master's Projects
For a given level of security, elliptic curve cryptography (ECC) offers improved efficiency over classic public key implementations. Point multiplication is the most common operation in ECC and, consequently, any significant improvement in perfor- mance will likely require accelerating point multiplication. In ECC, the Montgomery algorithm is widely used for point multiplication. The primary purpose of this project is to implement and analyze a parallel implementation of the Montgomery algorithm as it is used in ECC. Specifically, the performance of CPU-based Montgomery multiplication and a GPU-based implementation in CUDA are compared.
Big Data Analysis Using Amazon Web Services And Support Vector Machines, Dhruv Jalota
Big Data Analysis Using Amazon Web Services And Support Vector Machines, Dhruv Jalota
Master's Projects
This writing project aims to apply the supervised machine learning technique known as Support Vector Machines to a large labeled data set, to attempt to classify an unlabeled data set using the result of training on the labeled data set, and hence perform an analysis of the various results obtained using different Amazon Elastic Cloud Compute instances, sizes of input data set, and different parameters or kernels of the SVM tool. The given data set is relatively large for SVM and the tool being used, known as libsvm, having approximately 1.3 million training examples and 341 attributes with binary classification …
Using Social Networks For Assessing Company Sales And Marketing Programs, Vance Tomchalk
Using Social Networks For Assessing Company Sales And Marketing Programs, Vance Tomchalk
Master's Projects
During the course of an extended sales period for a company’s given product line, there are many events that affect the success of its sales. Some of these events include economic downturns, unforeseen shortages and delays that effect the supply chain for the product, and product quality issues that change the perception of the product as a safe and cost-effective choice. In many instances, these events can be tracked by analyzing the signals and messaging present in the social networking media. This analysis requires careful consideration, which the metrics provided by software tools and algorithms lend considerable aid.
User Profiling In Gui Based Windows Systems For Intrusion Detection, Arshi Agrawal
User Profiling In Gui Based Windows Systems For Intrusion Detection, Arshi Agrawal
Master's Projects
Intrusion detection is the process of identifying any unauthorized access to a sys- tem. This process inspects user behavior to identify any possible attack or intrusion. There exists two type of intrusion detection systems (IDSs): signature-based IDS and anomaly-based IDS. This project concentrates on anomaly-based intrusion detection technique. This technique is based on the deviation of intruder’s actions from the authenticated user’s actions. Much previous research has focused on the deviation of command line input in UNIX systems. However, these techniques fail to detect attacks on modern GUI- based systems, where typical user activities include mouse movements and keystrokes. Our …
Yioop Full Historical Indexing In Cache Navigation, Akshat Kukreti
Yioop Full Historical Indexing In Cache Navigation, Akshat Kukreti
Master's Projects
This project adds new cache-related features to Yioop, an Open Source, PHP-based search engine. Search engines often maintain caches of pages downloaded by their crawler. Commercial search engines like Google display a link to the cached version of a web page along with the search results for that particular web page. The first feature enables users to navigate through Yioop's entire cache. When a cached page is displayed along with its contents, links to cached pages saved in the past are also displayed. The feature also enables users to navigate cache history based on year and month. This feature is …
Big Data Classification Using Decision Trees On The Cloud, Chinmay Bhawe
Big Data Classification Using Decision Trees On The Cloud, Chinmay Bhawe
Master's Projects
This writing project addresses the topic of attempting to use machine learning on very large data sets on cloud servers. The project consists of two phases. The first being developing a machine learning system which will learn on the data provided by IBM for the “IBM Watson Great minds Challenge SJSU Pilot” competition and providing the best possible results on the evaluation data set, also provided by the IBM Watson team. This will serve as a basis for the second phase of the project, in which the objective is to move the machine learning system on to a cloud server, …
Enhanced Clustering Of Technology Tweets, Ananth Gopal
Enhanced Clustering Of Technology Tweets, Ananth Gopal
Master's Projects
Ever since Twitter has been widely accepted and has become an immensely popular micro blogging website, it is being used as a primary source of news; be it related to sports, entertainment, politics or technology by several users. It has been proven earlier that the elimination of stop words has a positive impact on the clustering of technology related tweets. The focus of this paper is to enhance the quality of clustering of the technology related Tweets by developing a semi-automated approach to eliminating stop words and by making use of a combination of Canopy and K-means clustering algorithms. The …
Cloud Storage Performance And Security Analysis With Hadoop And Gridftp, Wei-Li Liu
Cloud Storage Performance And Security Analysis With Hadoop And Gridftp, Wei-Li Liu
Master's Projects
Even though cloud server has been around for a few years, most of the web hosts today have not converted to cloud yet. If the purpose of the cloud server is distributing and storing files on the internet, FTP servers were much earlier than the cloud. FTP server is sufficient to distribute content on the internet. Therefore, is it worth to shift from FTP server to cloud server? The cloud storage provider declares high durability and availability for their users, and the ability to scale up for more storage space easily could save users tons of money. However, does it …
Modular Approach To Big Data Using Neural Networks, Animesh Dutta
Modular Approach To Big Data Using Neural Networks, Animesh Dutta
Master's Projects
Machine learning can be used to recognize patterns, classify data into classes and make predictions. Neural Networks are one of the many machine learning tools that are capable of performing these tasks. The greatest challenges that we face while dealing with the IBM Watson dataset is the high amount of dimensionality, both in terms of the number of features the data has, as well the number of rows of data we are dealing with. The aim of the project is to identify a course of action that can be chosen when dealing with similar problems. The project aims at setting …
Variation Of Instructor-Student Interactions In An Introductory Interactive Physics Course, Emily West, Cassandra Paul, David Webb, Wendell Potter
Variation Of Instructor-Student Interactions In An Introductory Interactive Physics Course, Emily West, Cassandra Paul, David Webb, Wendell Potter
Faculty Publications
The physics instruction at UC Davis for life science majors takes place in a long-standing reformed large-enrollment physics course in which the discussion or laboratory instructors (primarily graduate student teaching assistants) implement the interactive-engagement (IE) elements of the course. Because so many different instructors participate in disseminating the IE course elements, we find it essential to the instructors’ professional development to observe and document the student-instructor interactions within the classroom. Out of this effort, we have developed a computerized real-time instructor observation tool (RIOT) to take data of student-instructor interactions. We use the RIOT to observe 29 different instructors for …
A Short Introduction To Numerical Linked-Cluster Expansions, Baoming Tang, Ehsan Khatami, Marcos Rigol
A Short Introduction To Numerical Linked-Cluster Expansions, Baoming Tang, Ehsan Khatami, Marcos Rigol
Faculty Publications
We provide a pedagogical introduction to numerical linked-cluster expansions (NLCEs). We sketch the algorithm for generic Hamiltonians that only connect nearest-neighbor sites in a finite cluster with open boundary conditions. We then compare results for a specific model, the Heisenberg model, in each order of the NLCE with the ones for the finite cluster calculated directly by means of full exact diagonalization. We discuss how to reduce the computational cost of the NLCE calculations by taking into account symmetries and topologies of the linked clusters. Finally, we generalize the algorithm to the thermodynamic limit, and discuss several numerical resummation techniques …
Leeside Boundary Layer Confluence And Afternoon Thunderstorms Over Mayaguez, Puerto Rico, Mark Jury, Sen Chiao
Leeside Boundary Layer Confluence And Afternoon Thunderstorms Over Mayaguez, Puerto Rico, Mark Jury, Sen Chiao
Faculty Publications, Meteorology and Climate Science
The midsummer boundary layer (BL) circulation and afternoon thunderstorm convection on the lee side of Puerto Rico is studied using observations and high-resolution models. Satellite infrared data help to identify cases on 5 and 14 June 2010 when midday surface temperatures show a 2°C gradient between land and sea and afternoon cloud-top temperatures <−60°C. Acoustic sounder profiles are analyzed for climatology, wind shear, turbulence, and diurnal cycles in the 40-300-m layer. Weather Research and Forecasting (WRF) model simulations indicate that sea-breeze flow is entrained into convective cells near Mayaguez, Puerto Rico. The simulated BL wind shear is too weak (0.5 × 10−2 s−1) in comparison with the acoustic sounder (2 × 10−2 s−1). Model 900-hPa winds are southeasterly and spread simulated convection too far north in comparison with radar. The pattern of near-surface winds in the island wake triggers afternoon thunderstorms near Mayaguez. A feature of the confluent circulation around Puerto Rico is opposing shear zones on the leeward corners of the island and a sea breeze of 5 m s−1 over the west coast during midday. [ABSTRACT FROM AUTHOR] . Copyright of Journal of Applied Meteorology & Climatology is the property of American Meteorological Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.).
Evaluation Of Wrf-Sfire Performance With Field Observations From The Fireflux Experiment, A. Kochanski, M. Jenkins, J. Mandel, J. Beezley, Craig Clements, S. Krueger
Evaluation Of Wrf-Sfire Performance With Field Observations From The Fireflux Experiment, A. Kochanski, M. Jenkins, J. Mandel, J. Beezley, Craig Clements, S. Krueger
Faculty Publications, Meteorology and Climate Science
This study uses in situ measurements collected during the FireFlux field experiment to evaluate and improve the performance of the coupled atmosphere–fire model WRF-SFIRE. The simulation by WRF-SFIRE of the experimental burn shows that WRF-SFIRE is capable of providing realistic head-fire rate of spread and vertical temperature structure of the fire plume, and fire-induced surface flow and vertical velocities within the plume up to 10 m above ground level. The simulation captured the changes in wind speed and direction before, during, and after fire front passage, along with the arrival times of wind speed, temperature, and updraft maxima, at the …
Kinematic Structure Of A Wildland Fire Plume Observed By Doppler Lidar, A. Charland, Craig Clements
Kinematic Structure Of A Wildland Fire Plume Observed By Doppler Lidar, A. Charland, Craig Clements
Faculty Publications, Meteorology and Climate Science
Wildland fires present a challenging environment to make meteorological measurements. Observations in the vicinity of wildland fires are needed to better understand fire-atmosphere interactions and to provide data for the evaluation of coupled fire-atmosphere models. An observational study was conducted during a low-intensity prescribed fire in an area of complex terrain with grass fuels east of San José, California. A ground-based scanning Doppler lidar acquired radial wind velocities and backscatter intensity in and around the fire plume from multiple horizontal and vertical scans. The development of a convergence zone was consistently observed to exist downwind of the plume and was …
Application Of Social Network Metrics To A Trust-Aware Collaborative Model For Generating Personalized User Recommendations, Iraklis Varlamis, Magdalini Eirinaki, Malamati Louta
Application Of Social Network Metrics To A Trust-Aware Collaborative Model For Generating Personalized User Recommendations, Iraklis Varlamis, Magdalini Eirinaki, Malamati Louta
Faculty Publications
Social network analysis has emerged as a key technique in modern sociology, but has recently gained a lot of interest in Web mining research, because of the advent and the increasing popularity of social media, such as blogs, social networks, micro-blogging, customer review sites etc. Such media often serve as platforms for information dissemination and product placement or promotion. One way to improve the quality of recommendations provided to the members of social networks is to use trustworthy resources. In this environment, community-based reputation can help estimating the trustworthiness of individual users. Consequently, influence and trust are becoming essential qualities …
Numerical Investigations Of Convective Initiation In Barbados, Kim Whitehall, Sen Chiao, Margarette Mayers-Als
Numerical Investigations Of Convective Initiation In Barbados, Kim Whitehall, Sen Chiao, Margarette Mayers-Als
Faculty Publications, Meteorology and Climate Science
Localized convection in Barbados accounts for hazardous conditions and a significant percentage of the island’s annual rainfall. The feature results in rainfall accumulations exceeding 50 mm in 3 hours or less, over isolated locations. Weather Research and Forecasting model (WRF) simulations are conducted for a rapid convective initiated and heavy precipitation event of 26 August 2008 over Barbados. The simulation results from the 1 km grid resolution domain depict that the shallow topography on the island plays a significant role in enhancing convective activity under weak synoptically disturbed conditions. The model results also demonstrate that the driving forces for the …
An Inventory Of The Stellar Initial Mass Function In Early-Type Galaxies, C. Tortora, Aaron J. Romanowsky, N. R. Napolitano
An Inventory Of The Stellar Initial Mass Function In Early-Type Galaxies, C. Tortora, Aaron J. Romanowsky, N. R. Napolitano
Faculty Publications
Given a flurry of recent claims for systematic variations in the stellar initial mass function (IMF), we carry out the first inventory of the observational evidence using different approaches. This includes literature results, as well as our own new findings from combined stellar population synthesis (SPS) and Jeans dynamical analyses of data on ~4500 early-type galaxies (ETGs) from the SPIDER project. We focus on the mass-to-light ratio mismatch relative to the Milky Way IMF, δIMF, correlated against the central stellar velocity dispersion, σsstarf. We find a strong correlation between δIMF and σsstarf, for a wide set of dark matter (DM) …
Students Talk About Energy In Project- Based Inquiry Science, Benedikt W. Harrer, Virginia J. Flood, Michael C. Wittmann
Students Talk About Energy In Project- Based Inquiry Science, Benedikt W. Harrer, Virginia J. Flood, Michael C. Wittmann
Faculty Publications
We examine the types of emergent language eighth grade students in rural Maine middle schools use when they discuss energy in their first experiences with Project-Based Inquiry Science: Energy, a research-based curriculum that uses a specific language for talking about energy. By comparative analysis of the language used by the curriculum materials to students’ language, we find that students’ talk is at times more aligned with a Stores and Transfer model of energy than the Forms model supported by the curriculum.
Productive Resources In Students’ Ideas About Energy: An Alternative Analysis Of Watts’ Original Interview Transcripts, Benedikt W. Harrer, Virginia J. Flood, Michael C. Wittmann
Productive Resources In Students’ Ideas About Energy: An Alternative Analysis Of Watts’ Original Interview Transcripts, Benedikt W. Harrer, Virginia J. Flood, Michael C. Wittmann
Faculty Publications
For over 30 years, researchers have investigated students’ ideas about energy with the intent of reforming instructional practice. In this pursuit, Watts contributed an influential study with his 1983 paper “Some alternative views of energy” [Phys. Educ. 18, 213 (1983)]. Watts’ “alternative frameworks” continue to be used for categorizing students’ non-normative ideas about energy. Using a resources framework, we propose an alternate analysis of student responses from Watts’ interviews. In our analysis, we show how students’ activated resources about energy are disciplinarily productive. We suggest that fostering seeds of scientific understandings in students’ ideas about energy may play an important …
Planetary Nebula Spectrograph Survey Of S0 Galaxy Kinematics – Ii. Clues To The Origins Of S0 Galaxies, A. Cortesi, M. R. Merrifield, L. Coccato, M. Arnaboldi, O. Gerhard, Aaron J. Romanowsky, N. G. Douglass, K. Kuiijken, M. Capaccioli, K. C. Freeman, K. Saha, A. L. Chies-Santos
Planetary Nebula Spectrograph Survey Of S0 Galaxy Kinematics – Ii. Clues To The Origins Of S0 Galaxies, A. Cortesi, M. R. Merrifield, L. Coccato, M. Arnaboldi, O. Gerhard, Aaron J. Romanowsky, N. G. Douglass, K. Kuiijken, M. Capaccioli, K. C. Freeman, K. Saha, A. L. Chies-Santos
Faculty Publications
The stellar kinematics of the spheroids and discs of S0 galaxies contain clues to their formation histories. Unfortunately, it is difficult to disentangle the two components and to recover their stellar kinematics in the faint outer parts of the galaxies using conventional absorption line spectroscopy. This paper therefore presents the stellar kinematics of six S0 galaxies derived from observations of planetary nebulae, obtained using the Planetary Nebula Spectrograph. To separate the kinematics of the two components, we use a maximum-likelihood method that combines the discrete kinematic data with a photometric component decomposition. The results of this analysis reveal that: the …
The Planetary Nebula Spectrograph Survey Of S0 Galaxy Kinematics. Data And Overview, A. Cortesi, M. Arnaboldi, L. Coccato, M. R. Merrifield, O. Gerhard, S. Bamford, Aaron J. Romanowsky, N. R. Napolitano, N. G. Douglas, K. Kuiijken, M. Capaccioli, K. C. Freeman, A. L. Chies-Santos, V. Pota
The Planetary Nebula Spectrograph Survey Of S0 Galaxy Kinematics. Data And Overview, A. Cortesi, M. Arnaboldi, L. Coccato, M. R. Merrifield, O. Gerhard, S. Bamford, Aaron J. Romanowsky, N. R. Napolitano, N. G. Douglas, K. Kuiijken, M. Capaccioli, K. C. Freeman, A. L. Chies-Santos, V. Pota
Faculty Publications
The origins of S0 galaxies remain obscure, with various mechanisms proposed for their formation, likely depending on environment. These mechanisms would imprint different signatures in the galaxies' stellar kinematics out to large radii, offering a method for distinguishing between them. We aim to study a sample of six S0 galaxies from a range of environments, and use planetary nebulae (PNe) as tracers of their stellar populations out to very large radii, to determine their kinematics in order to understand their origins. Using a special-purpose instrument, the Planetary Nebula Spectrograph, we observe and extract PNe catalogues for these six systems*. We …
The Sluggs Survey: Wide Field Imaging Of The Globular Cluster System Of Ngc 4278, C. Usher, D. A. Forbes, L. R. Spitler, J. P. Brodie, Aaron J. Romanowsky, J. Strader, K. A. Woodley
The Sluggs Survey: Wide Field Imaging Of The Globular Cluster System Of Ngc 4278, C. Usher, D. A. Forbes, L. R. Spitler, J. P. Brodie, Aaron J. Romanowsky, J. Strader, K. A. Woodley
Faculty Publications
We use multipointing Hubble Space Telescope Advanced Camera for Surveys and wide field Subaru Suprime-Cam imaging to study the globular cluster system of the L* elliptical galaxy NGC 4278. We have also obtained a handful of new globular cluster spectra with the Keck Deep Imaging Multi-Object Spectrograph. We determine the globular cluster surface density profile and use it to calculate the total number of globular clusters, finding the system to be slightly more populous than average for galaxies of its luminosity. We find clear evidence for bimodality in the globular cluster colour distribution and for a colour–magnitude relation in the …
The Sluggs Survey: Probing The Supermassive Blackhole Connection With Bulges And Haloes Using Red And Blue Globular Cluster Systems, V. Pota, A. W. Graham, D. A. Forbes, Aaron J. Romanowsky, A. J. Brodie, J. Strader
The Sluggs Survey: Probing The Supermassive Blackhole Connection With Bulges And Haloes Using Red And Blue Globular Cluster Systems, V. Pota, A. W. Graham, D. A. Forbes, Aaron J. Romanowsky, A. J. Brodie, J. Strader
Faculty Publications
Understanding whether the bulge or the halo provides the primary link to the growth of supermassive black holes has strong implications for galaxy evolution and supermassive black hole formation itself. In this paper, we approach this issue by investigating extragalactic globular cluster (GC) systems, which can be used to probe the physics of both the bulge and the halo of the host galaxy. We study the relation between the supermassive black hole masses (MBH) and the GC system velocity dispersions (σGC) using an updated and improved sample of 21 galaxies. We exploit the dichotomy of GC system colours, to test …
Mond And Imf Variations In Early-Type Galaxies From Atlas3d, C. Tortora, Aaron J. Romanowsky, V. F. Cardone, N. R. Napolitano, Ph Jetzer
Mond And Imf Variations In Early-Type Galaxies From Atlas3d, C. Tortora, Aaron J. Romanowsky, V. F. Cardone, N. R. Napolitano, Ph Jetzer
Faculty Publications
No abstract provided.
The Sluggs Survey: Outer Triaxiality In The Fast Rotator Elliptical Ngc 4473, C. Foster, J. A. Arnold, D. A. Forbes, N. Pastorello, Aaron J. Romanowsky, L. R. Spitler, J. Strader, J. P. Brodie
The Sluggs Survey: Outer Triaxiality In The Fast Rotator Elliptical Ngc 4473, C. Foster, J. A. Arnold, D. A. Forbes, N. Pastorello, Aaron J. Romanowsky, L. R. Spitler, J. Strader, J. P. Brodie
Faculty Publications
Systematic surveys of nearby early-type galaxies using integral field unit (IFU) spectrograph data have revealed that galaxies can hide interesting structures only visible through kinematic studies. As part of their pioneering work, the ATLAS3D team have shown that most morphologically elliptical galaxies are centrally kinematically disc like. Hence, while global morphology suggests that ellipticals are ellipsoidal/triaxial in shape, their central kinematics may be consistent with (inclined) oblate systems. Here, we study the fast rotator elliptical galaxy: NGC 4473. Using slitlets, we obtain galaxy light kinematics out to unprecedentedly large galactocentric radii (2.5 effective radii). While we confirm the IFU results …
The Densest Galaxy, J. Strader, A. C. Seth, J. P. Brodie, D. A. Forbes, G. Fabbiano, Aaron J. Romanowsky, C. Conroy, N. Caldwell, V. Pota, C. Usher, J. A. Arnold
The Densest Galaxy, J. Strader, A. C. Seth, J. P. Brodie, D. A. Forbes, G. Fabbiano, Aaron J. Romanowsky, C. Conroy, N. Caldwell, V. Pota, C. Usher, J. A. Arnold
Faculty Publications
We report the discovery of a remarkable ultra-compact dwarf galaxy around the massive Virgo elliptical galaxy NGC 4649 (M60), which we call M60-UCD1. With a dynamical mass of 2.0 × 108 M ☉ but a half-light radius of only ~24 pc, M60-UCD1 is more massive than any ultra-compact dwarfs of comparable size, and is arguably the densest galaxy known in the local universe. It has a two-component structure well fit by a sum of Sérsic functions, with an elliptical, compact (rh = 14 pc; n ~ 3.3) inner component and a round, exponential, extended (rh = 49 pc) outer component. …
Filling The Gap: A New Class Of Old Star Cluster?, D. A. Forbes, V. Pota, C. Usher, Aaron J. Romanowsky, J. Strader, J. P. Brodie, J. A. Arnold, L. R. Spitler
Filling The Gap: A New Class Of Old Star Cluster?, D. A. Forbes, V. Pota, C. Usher, Aaron J. Romanowsky, J. Strader, J. P. Brodie, J. A. Arnold, L. R. Spitler
Faculty Publications
It is not understood whether long-lived star clusters possess a continuous range of sizes and masses (and hence densities) or if rather, they should be considered as distinct types with different origins. Utilizing the Hubble Space Telescope to measure sizes and long exposures on the Keck 10 m telescope to obtain distances, we have discovered the first confirmed star clusters that lie within a previously claimed size–luminosity gap dubbed the ‘avoidance zone’ by Hwang et al. The existence of these star clusters extends the range of sizes, masses and densities for star clusters, and argues against current formation models that …
The Sluggs Survey: The Globular Cluster Systems Of Three Early-Type Galaxies Using Wide-Field Imaging, S. S. Kartha, D. A. Forbes, L. R. Spitler, Aaron J. Romanowsky, J. A. Arnold, J. P. Brodie
The Sluggs Survey: The Globular Cluster Systems Of Three Early-Type Galaxies Using Wide-Field Imaging, S. S. Kartha, D. A. Forbes, L. R. Spitler, Aaron J. Romanowsky, J. A. Arnold, J. P. Brodie
Faculty Publications
We present the results from a wide-field imaging study of globular cluster (GC) systems in three early-type galaxies. Combinations of Subaru/Suprime-Cam, CFHT/MegaCam and HST/WFPC2/ACS data were used to determine the GC system properties of three highly flattened galaxies NGC 720, NGC 1023 and NGC 2768. This work is the first investigation of the GC system in NGC 720 and NGC 2768 to very large galactocentric radius (∼ 100 kpc). The three galaxies have clear blue and red GC subpopulations. The radial surface densities of the GC systems are fitted with Sersic profiles, and detected out to 15, 8 and 10 …