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Full-Text Articles in Physical Sciences and Mathematics

A Discrete Chemo-Dynamical Model Of The Giant Elliptical Galaxy Ngc 5846: Dark Matter Fraction, Internal Rotation, And Velocity Anisotropy Out To Six Effective Radii, Ling Zhu, Aaron Romanowsky, Glenn Van De Ven, R. Long, Laura Watkins, Vincenzo Pota, Nicola Napolitano, Duncan Forbes, Jean Brodie, Caroline Foster Nov 2016

A Discrete Chemo-Dynamical Model Of The Giant Elliptical Galaxy Ngc 5846: Dark Matter Fraction, Internal Rotation, And Velocity Anisotropy Out To Six Effective Radii, Ling Zhu, Aaron Romanowsky, Glenn Van De Ven, R. Long, Laura Watkins, Vincenzo Pota, Nicola Napolitano, Duncan Forbes, Jean Brodie, Caroline Foster

Faculty Publications

We construct a suite of discrete chemo-dynamical models of the giant elliptical galaxy NGC 5846. These models are a powerful tool to constrain both the mass distribution and internal dynamics of multiple tracer populations. We use Jeans models to simultaneously fit stellar kinematics within the effective radius Re, planetary nebula (PN) radial velocities out to 3 Re, and globular cluster (GC) radial velocities and colours out to 6 Re. The best-fitting model is a cored dark matter halo which contributes ∼10 per cent of the total mass within 1 Re, and 67 per cent ± 10 per cent within 6 …


Ultraluminous X-Ray Bursts In Two Ultracompact Companions To Nearby Elliptical Galaxies, Jimmy Irwin, W. Maksym, Gregory Sivakoff, Aaron Romanowsky, Dacheng Lin, Tyler Speegle, Ian Prado, David Mildebrath, Jay Strader, Jifeng Liu, Jon Miller Oct 2016

Ultraluminous X-Ray Bursts In Two Ultracompact Companions To Nearby Elliptical Galaxies, Jimmy Irwin, W. Maksym, Gregory Sivakoff, Aaron Romanowsky, Dacheng Lin, Tyler Speegle, Ian Prado, David Mildebrath, Jay Strader, Jifeng Liu, Jon Miller

Faculty Publications

A search of archival X-ray data for 70 nearby galaxies has yielded two flaring sources in globular clusters or ultracompact dwarf companions of parent elliptical galaxies. One source flared once, and the other five times. When not flaring, these sources appear to be normal accreting neutron-star or black-hole X-ray binaries. Unlike magnetars and other bodies that produce repetitive flares of similar luminosity, they are located in old stellar populations.


Metallicity And Age Of The Stellar Stream Around The Disk Galaxy Ngc 5907, Seppo Laine, Carl Grillmair, Peter Capak, Richard Arendt, Aaron Romanowsky, David Martínez-Delgado, Matthew Ashby, James Davies, Stephen Majewski, Jean Brodie, R. Gabany, Jacob Arnold Sep 2016

Metallicity And Age Of The Stellar Stream Around The Disk Galaxy Ngc 5907, Seppo Laine, Carl Grillmair, Peter Capak, Richard Arendt, Aaron Romanowsky, David Martínez-Delgado, Matthew Ashby, James Davies, Stephen Majewski, Jean Brodie, R. Gabany, Jacob Arnold

Faculty Publications

Stellar streams have become central to studies of the interaction histories of nearby galaxies. To characterize the most prominent parts of the stellar stream around the well-known nearby (d = 17 Mpc) edge-on disk galaxy NGC 5907, we have obtained and analyzed new, deep gri Subaru/Suprime-Cam and 3.6 μm Spitzer/Infrared Array Camera observations. Combining the near-infrared 3.6 μm data with visible-light images allows us to use a long wavelength baseline to estimate the metallicity and age of the stellar population along an ~60 kpc long segment of the stream. We have fitted the stellar spectral energy distribution with a single-burst …


The Mass Discrepancy Acceleration Relation In Early-Type Galaxies: Extended Mass Profiles And The Phantom Menace To Mond, Joachim Janz, Michele Cappellari, Aaron Romanowsky, Luca Ciotti, Adebusola Alabi, Duncan Forbes Sep 2016

The Mass Discrepancy Acceleration Relation In Early-Type Galaxies: Extended Mass Profiles And The Phantom Menace To Mond, Joachim Janz, Michele Cappellari, Aaron Romanowsky, Luca Ciotti, Adebusola Alabi, Duncan Forbes

Faculty Publications

The dark matter (DM) haloes around spiral galaxies appear to conspire with their baryonic content: empirically, significant amounts of DM are inferred only below a universal characteristic acceleration scale. Moreover, the discrepancy between the baryonic and dynamical mass, which is usually interpreted as the presence of DM, follows a very tight mass discrepancy acceleration (MDA) relation. Its universality, and its tightness in spiral galaxies, poses a challenge for the DM interpretation and was used to argue in favour of MOdified Newtonian Dynamics (MOND). Here, we test whether or not this applies to early-type galaxies. We use the dynamical models of …


The Sluggs Survey: The Mass Distribution In Early-Type Galaxies Within Five Effective Radii And Beyond, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader, Joachim Janz, Vincenzo Pota, Nicola Pastorello, Christopher Usher, Lee Spitler, Caroline Foster, Zachary Jennings, Alexa Villaume, Sreeja Kartha Aug 2016

The Sluggs Survey: The Mass Distribution In Early-Type Galaxies Within Five Effective Radii And Beyond, Adebusola Alabi, Duncan Forbes, Aaron Romanowsky, Jean Brodie, Jay Strader, Joachim Janz, Vincenzo Pota, Nicola Pastorello, Christopher Usher, Lee Spitler, Caroline Foster, Zachary Jennings, Alexa Villaume, Sreeja Kartha

Faculty Publications

We study mass distributions within and beyond 5 effective radii (Re) in 23 early-type galaxies from the SAGES Legacy Unifying Globulars and Galaxies Survey, using their globular cluster (GC) kinematic data. The data are obtained with Keck/DEep Imaging Multi-Object Spectrograph, and consist of line-of-sight velocities for ∼3500 GCs, measured with a high precision of ∼15 km s−1 per GC and extending out to ∼13 Re. We obtain the mass distribution in each galaxy using the tracer mass estimator of Watkins et al. and account for kinematic substructures, rotation of the GC systems and galaxy flattening in our mass estimates. The …


The Sluggs Survey*: Exploring The Globular Cluster Systems Of The Leo Ii Group And Their Global Relationships, Sreeja Kartha, Duncan Forbes, Adebusola Alabi, Jean Brodie, Aaron Romanowsky, Jay Strader, Lee Spitler, Zachary Jennings, Joel Roediger May 2016

The Sluggs Survey*: Exploring The Globular Cluster Systems Of The Leo Ii Group And Their Global Relationships, Sreeja Kartha, Duncan Forbes, Adebusola Alabi, Jean Brodie, Aaron Romanowsky, Jay Strader, Lee Spitler, Zachary Jennings, Joel Roediger

Faculty Publications

We present an investigation of the globular cluster (GC) systems of NGC 3607 and NGC 3608 as part of the ongoing SLUGGS (SAGES Legacy Unifying Globulars and GalaxieS) survey. We use wide-field imaging data from the Subaru telescope in the g, r and i filters to analyse the radial density, colour and azimuthal distributions of both GC systems. With the complementary kinematic data obtained from the Keck II telescope, we measure the radial velocities of a total of 81 GCs. Our results show that the GC systems of NGC 3607 and NGC 3608 have a detectable spatial extent of ∼15 …


The Sluggs Survey: Globular Clusters And The Dark Matter Content Of Early-Type Galaxies, Duncan Forbes, Adebusola Alabi, Aaron Romanowsky, Jean Brodie, Jay Strader, Christopher Usher, Vincenzo Pota May 2016

The Sluggs Survey: Globular Clusters And The Dark Matter Content Of Early-Type Galaxies, Duncan Forbes, Adebusola Alabi, Aaron Romanowsky, Jean Brodie, Jay Strader, Christopher Usher, Vincenzo Pota

Faculty Publications

No abstract provided.


Erratum: The Sluggs Survey: The Globular Cluster Systems Of Three Early-Type Galaxies Using Wide-Field Imaging, Sreeja Kartha, Duncan Forbes, Lee Spitler, Aaron Romanowsky, Jacob Arnold, Jean Brodie Apr 2016

Erratum: The Sluggs Survey: The Globular Cluster Systems Of Three Early-Type Galaxies Using Wide-Field Imaging, Sreeja Kartha, Duncan Forbes, Lee Spitler, Aaron Romanowsky, Jacob Arnold, Jean Brodie

Faculty Publications

The paper ‘The SLUGGS survey: the globular cluster systems of three early-type galaxies using wide-field imaging’ was published in Monthly Notices of the Royal Astronomical Society, 437, 273 – 292 (2014).


The Sluggs Survey: The Assembly Histories Of Individual Early-Type Galaxies, Duncan Forbes, Aaron Romanowsky, Nicola Pastorello, Caroline Foster, Jean Brodie, Jay Strader, Christopher Usher, Vincenzo Pota Apr 2016

The Sluggs Survey: The Assembly Histories Of Individual Early-Type Galaxies, Duncan Forbes, Aaron Romanowsky, Nicola Pastorello, Caroline Foster, Jean Brodie, Jay Strader, Christopher Usher, Vincenzo Pota

Faculty Publications

Early-type (E and S0) galaxies may have assembled via a variety of different evolutionary pathways. Here, we investigate these pathways by comparing the stellar kinematic properties of 24 early-type galaxies from the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey with the hydrodynamical simulations of Naab et al. In particular, we use the kinematics of starlight up to 4 effective radii (Re) as diagnostics of galaxy inner and outer regions, and assign each galaxy to one of six Naab et al. assembly classes. The majority of our galaxies (14/24) have kinematic characteristics that indicate an assembly history dominated by gradual …


Discovery Of An Ultra-Diffuse Galaxy In The Pisces-Perseus Supercluster, David Martínez-Delgado, Ronald Läsker, Margarita Sharina, Elisa Toloba, Jürgen Fliri, Rachael Beaton, David Valls-Gabaud, Igor Karachentsev, Taylor Chonis, Eva Grebel, Duncan Forbes, Aaron Romanowsky, J. Gallego-Laborda, Karel Teuwen, M. Gómez-Flechoso, Jie Wang, Puragra Guhathakurta, Serafim Kaisin, Nhung Ho Mar 2016

Discovery Of An Ultra-Diffuse Galaxy In The Pisces-Perseus Supercluster, David Martínez-Delgado, Ronald Läsker, Margarita Sharina, Elisa Toloba, Jürgen Fliri, Rachael Beaton, David Valls-Gabaud, Igor Karachentsev, Taylor Chonis, Eva Grebel, Duncan Forbes, Aaron Romanowsky, J. Gallego-Laborda, Karel Teuwen, M. Gómez-Flechoso, Jie Wang, Puragra Guhathakurta, Serafim Kaisin, Nhung Ho

Faculty Publications

We report the discovery of DGSAT I, an ultra-diffuse, quenched galaxy located 10fdg4 in projection from the Andromeda galaxy (M31). This low-surface brightness galaxy (μV = 24.8 mag arcsec−2), found with a small amateur telescope, appears unresolved in sub-arcsecond archival Subaru/Suprime-Cam images, and hence has been missed by optical surveys relying on resolved star counts, in spite of its relatively large effective radius (Re(V) = 12'') and proximity (15') to the well-known dwarf spheroidal galaxy And II. Its red color (V − I = 1.0), shallow Sérsic index (nV = 0.68), and the absence of detectable Hα emission are typical …


The Sluggs Survey: Chromodynamical Modelling Of The Lenticular Galaxy Ngc 1023, Arianna Cortesi, Ana Chies-Santos, Vincenzo Pota, Caroline Foster, Lodovico Coccato, Claudia Mendes De Oliveira, Duncan Forbes, Michael Merrifield, Steven Bamford, Aaron Romanowsky, Jean Brodie, Sreeja Kartha, Adebusola Alabi, Robert Proctor, Andres Almeida Mar 2016

The Sluggs Survey: Chromodynamical Modelling Of The Lenticular Galaxy Ngc 1023, Arianna Cortesi, Ana Chies-Santos, Vincenzo Pota, Caroline Foster, Lodovico Coccato, Claudia Mendes De Oliveira, Duncan Forbes, Michael Merrifield, Steven Bamford, Aaron Romanowsky, Jean Brodie, Sreeja Kartha, Adebusola Alabi, Robert Proctor, Andres Almeida

Faculty Publications

Globular clusters (GCs) can be considered discrete, long-lived, dynamical tracers that retain crucial information about the assembly history of their parent galaxy. In this paper, we present a new catalogue of GC velocities and colours for the lenticular galaxy NGC 1023, we study their kinematics and spatial distribution, in comparison with the underlying stellar kinematics and surface brightness profile, and we test a new method for studying GC properties. Specifically, we decompose the galaxy light into its spheroid (assumed to represent the bulge+halo components) and disc components and use it to assign to each GC a probability of belonging to …


The Sluggs Survey: Stellar Kinematics, Kinemetry And Trends At Large Radii In 25 Early-Type Galaxies, Caroline Foster, Nicola Pastorello, Joel Roediger, Jean Brodie, Duncan Forbes, Sreeja Kartha, Vincenzo Pota, Aaron Romanowsky, Lee Spitler, Jay Strader, Christopher Usher, Jacob Arnold Mar 2016

The Sluggs Survey: Stellar Kinematics, Kinemetry And Trends At Large Radii In 25 Early-Type Galaxies, Caroline Foster, Nicola Pastorello, Joel Roediger, Jean Brodie, Duncan Forbes, Sreeja Kartha, Vincenzo Pota, Aaron Romanowsky, Lee Spitler, Jay Strader, Christopher Usher, Jacob Arnold

Faculty Publications

Due to longer dynamical time-scales, the outskirts of early-type galaxies retain the footprint of their formation and assembly. Under the popular two-phase galaxy formation scenario, an initial in situ phase of star formation is followed by minor merging and accretion of ex situ stars leading to the expectation of observable transitions in the kinematics and stellar populations on large scales. However, observing the faint galactic outskirts is challenging, often leaving the transition unexplored. The large-scale, spatially resolved stellar kinematic data from the SAGES Legacy Unifying Galaxies and GlobularS (SLUGGS) survey are ideal for detecting kinematic transitions. We present kinematic maps …


Satellite Accretion In Action: A Tidally Disrupting Dwarf Spheroidal Around The Nearby Spiral Galaxy Ngc 253, Aaron Romanowsky, David Martínez-Delgado, Nicolas Martin, Gustavo Morales, Zachary Jennings, R. Gabany, Jean Brodie, Eva Grebel, Johannes Schedler, Michael Sidonio Mar 2016

Satellite Accretion In Action: A Tidally Disrupting Dwarf Spheroidal Around The Nearby Spiral Galaxy Ngc 253, Aaron Romanowsky, David Martínez-Delgado, Nicolas Martin, Gustavo Morales, Zachary Jennings, R. Gabany, Jean Brodie, Eva Grebel, Johannes Schedler, Michael Sidonio

Faculty Publications

No abstract provided.


Erratum: Global Properties Of ‘Ordinary’ Early-Type Galaxies: Photometry And Spectroscopy Of Stars And Globular Clusters In Ngc 4494, Caroline Foster, Lee Spitler, Aaron Romanowsky, Duncan Forbes, Vincenzo Pota, Kenji Bekki, Jay Strader, Robert Proctor, Jacob Arnold, Jean Brodie Feb 2016

Erratum: Global Properties Of ‘Ordinary’ Early-Type Galaxies: Photometry And Spectroscopy Of Stars And Globular Clusters In Ngc 4494, Caroline Foster, Lee Spitler, Aaron Romanowsky, Duncan Forbes, Vincenzo Pota, Kenji Bekki, Jay Strader, Robert Proctor, Jacob Arnold, Jean Brodie

Faculty Publications

This is an erratum to the paper entitled “Global properties of ‘ordinary’ early-type galaxies: photometry and spectroscopy of stars and globular clusters in NGC 4494”, published in MNRAS, 2011, 415, 3393.


The Aimss Project – Iii. The Stellar Populations Of Compact Stellar Systems, Joachim Janz, Mark Norris, Duncan Forbes, Avon Huxor, Aaron Romanowsky, Matthias Frank, Carlos Escudero, Favio Faifer, Juan Forte, Sheila Kannappan, Claudia Maraston, Jean Brodie, Jay Strader, Bradley Thompson Feb 2016

The Aimss Project – Iii. The Stellar Populations Of Compact Stellar Systems, Joachim Janz, Mark Norris, Duncan Forbes, Avon Huxor, Aaron Romanowsky, Matthias Frank, Carlos Escudero, Favio Faifer, Juan Forte, Sheila Kannappan, Claudia Maraston, Jean Brodie, Jay Strader, Bradley Thompson

Faculty Publications

In recent years, a growing zoo of compact stellar systems (CSSs) have been found whose physical properties (mass, size, velocity dispersion) place them between classical globular clusters (GCs) and true galaxies, leading to debates about their nature. Here we present results using a so far underutilized discriminant, their stellar population properties. Based on new spectroscopy from 8–10m telescopes, we derive ages, metallicities, and [α/Fe] of 29 CSSs. These range from GCs with sizes of merely a few parsec to compact ellipticals (cEs) larger than M32. Together with a literature compilation, this provides a panoramic view of the stellar population characteristics …


Discovery Of The Candidate Off-Nuclear Ultrasoft Hyper-Luminous X-Ray Source 3xmm J141711.1+522541, Dacheng Lin, Eleazar Carrasco, Natalie Webb, Jimmy Irwin, Renato Dupke, Aaron Romanowsky, Enrico Ramirez-Ruiz, Jay Strader, Jeroen Homan, Didier Barret, Olivier Godet Jan 2016

Discovery Of The Candidate Off-Nuclear Ultrasoft Hyper-Luminous X-Ray Source 3xmm J141711.1+522541, Dacheng Lin, Eleazar Carrasco, Natalie Webb, Jimmy Irwin, Renato Dupke, Aaron Romanowsky, Enrico Ramirez-Ruiz, Jay Strader, Jeroen Homan, Didier Barret, Olivier Godet

Faculty Publications

No abstract provided.


An Overmassive Dark Halo Around An Ultra-Diffuse Galaxy In The Virgo Cluster, Michael Beasley, Aaron Romanowsky, Vincenzo Pota, Ignacio Navarro, David Martinez-Delgado, Fabian Neyer, Aaron Deich Jan 2016

An Overmassive Dark Halo Around An Ultra-Diffuse Galaxy In The Virgo Cluster, Michael Beasley, Aaron Romanowsky, Vincenzo Pota, Ignacio Navarro, David Martinez-Delgado, Fabian Neyer, Aaron Deich

Faculty Publications

No abstract provided.


First Results From The Madcash Survey: A Faint Dwarf Galaxy Companion To The Low-Mass Spiral Galaxy Ngc 2403 At 3.2 Mpc*, Jeffrey Carlin, David Sand, Paul Price, Beth Willman, Ananthan Karunakaran, Kristine Spekkens, Eric Bell, Jean Brodie, Denija Crnojević, Duncan Forbes, Jonathan Hargis, Evan Kirby, Robert Lupton, Annika Peter, Aaron Romanowsky, Jay Strader Jan 2016

First Results From The Madcash Survey: A Faint Dwarf Galaxy Companion To The Low-Mass Spiral Galaxy Ngc 2403 At 3.2 Mpc*, Jeffrey Carlin, David Sand, Paul Price, Beth Willman, Ananthan Karunakaran, Kristine Spekkens, Eric Bell, Jean Brodie, Denija Crnojević, Duncan Forbes, Jonathan Hargis, Evan Kirby, Robert Lupton, Annika Peter, Aaron Romanowsky, Jay Strader

Faculty Publications

No abstract provided.


Erratum: “Ngc 3628-Ucd1: A Possible Ω Cen Analog Embedded In A Stellar Stream” (2015, Apjl, 812, L10), Zachary Jennings, Aaron Romanowsky, Jean Brodie, Joachim Janz, Mark Norris, Duncan Forbes, David Martinez-Delgado, Martina Fagioli, Samantha Penny Jan 2016

Erratum: “Ngc 3628-Ucd1: A Possible Ω Cen Analog Embedded In A Stellar Stream” (2015, Apjl, 812, L10), Zachary Jennings, Aaron Romanowsky, Jean Brodie, Joachim Janz, Mark Norris, Duncan Forbes, David Martinez-Delgado, Martina Fagioli, Samantha Penny

Faculty Publications

No abstract provided.


Star Clusters In M31. Vii. Global Kinematics And Metallicity Subpopulations Of The Globular Clusters, Nelson Caldwell, Aaron Romanowsky Jan 2016

Star Clusters In M31. Vii. Global Kinematics And Metallicity Subpopulations Of The Globular Clusters, Nelson Caldwell, Aaron Romanowsky

Faculty Publications

We carry out a joint spatial–kinematical–metallicity analysis of globular clusters (GCs) around the Andromeda Galaxy (M31), using a homogeneous, high-quality spectroscopic data set. In particular, we remove the contaminating young clusters that have plagued many previous analyses. We find that the clusters can be divided into three major metallicity groups based on their radial distributions: (1) an inner metal-rich group ([Fe/H] > -0.4); (2) a group with intermediate metallicity (with median [Fe/H] = −1); and (3) a metal-poor group, with [Fe/H] < -1.5. The metal-rich group has kinematics and spatial properties like those of the disk of M31, while the two more metal-poor groups show mild prograde rotation overall, with larger dispersions—in contrast to previous claims of stronger rotation. The metal-poor GCs are the least concentrated group; such clusters occur five times less frequently in the central bulge than do clusters of higher metallicity. Despite some well-known differences between the M31 and Milky Way GC systems, our revised analysis points to remarkable similarities in their chemodynamical properties, which could help elucidate the different formation stages of galaxies and their GCs. In particular, the M31 results motivate further exploration of a metal-rich GC formation mode in situ, within high-redshift, clumpy galactic disks.


New Spectroscopic Technique Based On Coaddition Of Surface Brightness Fluctuations: Ngc 4449 And Its Stellar Tidal Stream, Elisa Toloba, Puragra Guhathakurta, Aaron Romanowsky, Jean Brodie, David Martínez-Delgado, Jacob Arnold, Neel Ramachandran, Kuriakose Theakanath Jan 2016

New Spectroscopic Technique Based On Coaddition Of Surface Brightness Fluctuations: Ngc 4449 And Its Stellar Tidal Stream, Elisa Toloba, Puragra Guhathakurta, Aaron Romanowsky, Jean Brodie, David Martínez-Delgado, Jacob Arnold, Neel Ramachandran, Kuriakose Theakanath

Faculty Publications

No abstract provided.


Stellar Populations Across The Black Hole Mass–Velocity Dispersion Relation, Ignacio Martín-Navarro, Jean Brodie, Remco Van Den Bosch, Aaron Romanowsky, Duncan Forbes Jan 2016

Stellar Populations Across The Black Hole Mass–Velocity Dispersion Relation, Ignacio Martín-Navarro, Jean Brodie, Remco Van Den Bosch, Aaron Romanowsky, Duncan Forbes

Faculty Publications

Coevolution between supermassive black holes (BH) and their host galaxies is universally adopted in models for galaxy formation. In the absence of feedback from active galactic nuclei (AGNs), simulated massive galaxies keep forming stars in the local universe. From an observational point of view, however, such coevolution remains unclear. We present a stellar population analysis of galaxies with direct BH mass measurements and the BH mass–σ relation as a working framework. We find that over-massive BH galaxies, i.e., galaxies lying above the best-fitting BH mass–σ line, tend to be older and more α-element-enhanced than under-massive BH galaxies. The scatter in …


The Sluggs Survey: A New Mask Design To Reconstruct The Stellar Populations And Kinematics Of Both Inner And Outer Galaxy Regions, Nicola Pastorello, Duncan Forbes, Adriano Poci, Aaron Romanowsky, Richard Mcdermid, Adebusola Alabi, Jean Brodie, Michele Cappellari, Vincenzo Pota, Caroline Foster Jan 2016

The Sluggs Survey: A New Mask Design To Reconstruct The Stellar Populations And Kinematics Of Both Inner And Outer Galaxy Regions, Nicola Pastorello, Duncan Forbes, Adriano Poci, Aaron Romanowsky, Richard Mcdermid, Adebusola Alabi, Jean Brodie, Michele Cappellari, Vincenzo Pota, Caroline Foster

Faculty Publications

Integral field unit spectrographs allow the 2D exploration of the kinematics and stellar populations of galaxies, although they are generally restricted to small fields-of-view. Using the large field-of-view of the DEIMOS multislit spectrograph on Keck and our Stellar Kinematics using Multiple Slits technique, we are able to extract sky-subtracted stellar light spectra to large galactocentric radii. Here, we present a new DEIMOS mask design named SuperSKiMS that explores large spatial scales without sacrificing high spatial sampling. We simulate a set of observations with such a mask design on the nearby galaxy NGC 1023, measuring stellar kinematics and metallicities out to …


A High Stellar Velocity Dispersion And ~100 Globular Clusters For The Ultra-Diffuse Galaxy Dragonfly 44, Pieter Van Dokkum, Roberto Abraham, Jean Brodie, Charlie Conroy, Shany Danieli, Allison Merritt, Lamiya Mowla, Aaron Romanowsky, Jielai Zhang Jan 2016

A High Stellar Velocity Dispersion And ~100 Globular Clusters For The Ultra-Diffuse Galaxy Dragonfly 44, Pieter Van Dokkum, Roberto Abraham, Jean Brodie, Charlie Conroy, Shany Danieli, Allison Merritt, Lamiya Mowla, Aaron Romanowsky, Jielai Zhang

Faculty Publications

No abstract provided.