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Multiwavelength, Machine Learning, And Parallax Studies Of X-Ray Binaries In Three Local Group Galaxies, Robin Arnason 2018 The University of Western Ontario

Multiwavelength, Machine Learning, And Parallax Studies Of X-Ray Binaries In Three Local Group Galaxies, Robin Arnason

Electronic Thesis and Dissertation Repository

X-ray binary stars are rare systems consisting of a black hole or neutron star and a main-sequence companion star. They are useful probes of galaxy properties and interesting laboratories for extreme physical conditions. In this thesis, I investigated the X-ray binary population of three galaxies in the Local Group.

The Sculptor Dwarf Spheroidal Galaxy offers the chance to study a primordial low-mass X-ray binary (LMXB) population in an isolated, low-metallicity environment. Combining X-ray, optical, and infrared observations, I have studied nine previously-identified and discovered four additional LMXB candidates in this galaxy. Of these candidates, all but one are either background ...


Dance Of Two Supermassive Binary Black Holes, Karishma Bansal 2018 University of New Mexico

Dance Of Two Supermassive Binary Black Holes, Karishma Bansal

Shared Knowledge Conference

Black holes exist in a various range of masses ranging from stellar mass (~ 10 Solar Mass) to Supermassive black holes (SMBHs, million to billion Solar Mass). It is expected that as the separation between the black holes decreases, emission of gravitational waves will grow stronger, which makes binary black holes one of the most promising sources for gravitational radiation detection. Gravitational waves from merging stellar-mass black holes have recently been discovered by LIGO; however, we are yet to detect them from binary SMBHs. These massive black holes reside at the heart of most of the galaxies and when two such ...


Chromodynamical Analysis Of Lenticular Galaxies Using Globular Clusters And Planetary Nebulae, Emilio Zanatta, Arianna Cortesi, Ana Chies-Santos, Duncan Forbes, Aaron Romanowsky, Adebusola Alabi, Lodovico Coccato, Claudia Mendes de Oliveira, Jean Brodie, Michael Merrifield 2018 Universidade Federal do Rio Grande do Sul

Chromodynamical Analysis Of Lenticular Galaxies Using Globular Clusters And Planetary Nebulae, Emilio Zanatta, Arianna Cortesi, Ana Chies-Santos, Duncan Forbes, Aaron Romanowsky, Adebusola Alabi, Lodovico Coccato, Claudia Mendes De Oliveira, Jean Brodie, Michael Merrifield

Faculty Publications

Recovering the origins of lenticular galaxies can shed light on the understanding of galaxy and compare them with the kinematics of planetary nebulae (PNe). The PNe and GC data come from the Planetary Nebulae Spectrograph and the SLUGGS Surveys. Through photometric spheroid-disc decomposition and PNe kinematics. we find the probability for a given GC to belong to either the spheroid or the disc of its host galaxy or be rejected from the model. We find that there is no correlation between the components that the GCs are likely to belong to and their colours. Particularly, for NGC 2768, we find ...


Chromodynamical Analysis Of Lenticular Galaxies Using Globular Clusters And Planetary Nebulae, Emilio J B Zanatta, Arianna Cortesi, Ana L. Chies-Santos, Duncan A. Forbes, Aaron J. Romanowsky, Adebusola B. Alabi, Lodovico Coccato, Claudia Mendes de Oliveira, Jean P. Brodie, Michael M. Merrifield 2018 Universidade Federal do Rio Grande do Sul

Chromodynamical Analysis Of Lenticular Galaxies Using Globular Clusters And Planetary Nebulae, Emilio J B Zanatta, Arianna Cortesi, Ana L. Chies-Santos, Duncan A. Forbes, Aaron J. Romanowsky, Adebusola B. Alabi, Lodovico Coccato, Claudia Mendes De Oliveira, Jean P. Brodie, Michael M. Merrifield

Aaron J. Romanowsky

Recovering the origins of lenticular galaxies can shed light on the understanding of galaxy and compare them with the kinematics of planetary nebulae (PNe). The PNe and GC data come from the Planetary Nebulae Spectrograph and the SLUGGS Surveys. Through photometric spheroid-disc decomposition and PNe kinematics. we find the probability for a given GC to belong to either the spheroid or the disc of its host galaxy or be rejected from the model. We find that there is no correlation between the components that the GCs are likely to belong to and their colours. Particularly, for NGC 2768, we find ...


Origins Of Ultradiffuse Galaxies In The Coma Cluster – I. Constraints From Velocity Phase Space, Adebusola Alabi, Anna Ferré-Mateu, Aaron Romanowsky, Jean Brodie, Duncan Forbes, Asher Wasserman, Sabine Bellstedt, Ignacio Martín-Navarro, Viraj Pandya, Maria Stone, Nobuhiro Okabe 2018 University of California Observatories

Origins Of Ultradiffuse Galaxies In The Coma Cluster – I. Constraints From Velocity Phase Space, Adebusola Alabi, Anna Ferré-Mateu, Aaron Romanowsky, Jean Brodie, Duncan Forbes, Asher Wasserman, Sabine Bellstedt, Ignacio Martín-Navarro, Viraj Pandya, Maria Stone, Nobuhiro Okabe

Faculty Publications

We use Keck/DEIMOS spectroscopy to confirm the cluster membership of 16 ultradiffuse galaxies (UDGs) in the Coma cluster, bringing the total number of spectroscopically confirmed UDGs from the Yagi et al. (Y16) catalogue to 25. We also identify a new cluster background UDG, confirming that most (∼95 per cent) of the UDGs in the Y16 catalogue belong to the Coma cluster. In this pilot study of Coma UDGs in velocity phase space, we find evidence of a diverse origin for Coma cluster UDGs, similar to normal dwarf galaxies. Some UDGs in our sample are consistent with being late infalls ...


Origins Of Ultradiffuse Galaxies In The Coma Cluster – I. Constraints From Velocity Phase Space, Adebusola B. Alabi, Anna Ferré-Mateu, Aaron J. Romanowsky, Jean P. Brodie, Duncan A. Forbes, Asher Wasserman, Sabine Bellstedt, Ignacio Martín-Navarro, Viraj Pandya, Maria B. Stone, Nobuhiro Okabe 2018 University of California Observatories

Origins Of Ultradiffuse Galaxies In The Coma Cluster – I. Constraints From Velocity Phase Space, Adebusola B. Alabi, Anna Ferré-Mateu, Aaron J. Romanowsky, Jean P. Brodie, Duncan A. Forbes, Asher Wasserman, Sabine Bellstedt, Ignacio Martín-Navarro, Viraj Pandya, Maria B. Stone, Nobuhiro Okabe

Aaron J. Romanowsky

We use Keck/DEIMOS spectroscopy to confirm the cluster membership of 16 ultradiffuse galaxies (UDGs) in the Coma cluster, bringing the total number of spectroscopically confirmed UDGs from the Yagi et al. (Y16) catalogue to 25. We also identify a new cluster background UDG, confirming that most (∼95 per cent) of the UDGs in the Y16 catalogue belong to the Coma cluster. In this pilot study of Coma UDGs in velocity phase space, we find evidence of a diverse origin for Coma cluster UDGs, similar to normal dwarf galaxies. Some UDGs in our sample are consistent with being late infalls ...


The Distance Of The Dark Matter Deficient Galaxy Ngc 1052–Df2, Pieter van Dokkum, Shany Danieli, Yotam Cohen, Aaron Romanowsky, Charlie Conroy 2018 Yale University

The Distance Of The Dark Matter Deficient Galaxy Ngc 1052–Df2, Pieter Van Dokkum, Shany Danieli, Yotam Cohen, Aaron Romanowsky, Charlie Conroy

Faculty Publications

We recently inferred that the galaxy NGC 1052–DF2 has little or no dark matter and a rich system of unusual globular clusters. We assumed that the galaxy is a satellite of the luminous elliptical galaxy NGC 1052 at ≈20 Mpc, on the basis of its surface brightness fluctuations (SBFs) distance of 19.0 ± 1.7 Mpc, its radial velocity of ≈1800 km s−1, and its projected position. Here we analyze the color–magnitude diagram (CMD) of NGC 1052–DF2, following the suggestion by Trujillo et al. that the tip of the red giant branch (TRGB) can be detected ...


The Distance Of The Dark Matter Deficient Galaxy Ngc 1052–Df2, Pieter van Dokkum, Shany Danieli, Yotam Cohen, Aaron J. Romanowsky, Charlie Conroy 2018 Yale University

The Distance Of The Dark Matter Deficient Galaxy Ngc 1052–Df2, Pieter Van Dokkum, Shany Danieli, Yotam Cohen, Aaron J. Romanowsky, Charlie Conroy

Aaron J. Romanowsky

We recently inferred that the galaxy NGC 1052–DF2 has little or no dark matter and a rich system of unusual globular clusters. We assumed that the galaxy is a satellite of the luminous elliptical galaxy NGC 1052 at ≈20 Mpc, on the basis of its surface brightness fluctuations (SBFs) distance of 19.0 ± 1.7 Mpc, its radial velocity of ≈1800 km s−1, and its projected position. Here we analyze the color–magnitude diagram (CMD) of NGC 1052–DF2, following the suggestion by Trujillo et al. that the tip of the red giant branch (TRGB) can be detected ...


The Sluggs Survey: The Inner Dark Matter Density Slope Of The Massive Elliptical Galaxy Ngc 1407, Asher Wasserman, Aaron Romanowsky, Jean Brodie, Pieter van Dokkum, Charlie Conroy, Alexa Villaume, Duncan Forbes, Jay Strader, Adebusola Alabi, Sabine Bellstedt 2018 University of California, Santa Cruz

The Sluggs Survey: The Inner Dark Matter Density Slope Of The Massive Elliptical Galaxy Ngc 1407, Asher Wasserman, Aaron Romanowsky, Jean Brodie, Pieter Van Dokkum, Charlie Conroy, Alexa Villaume, Duncan Forbes, Jay Strader, Adebusola Alabi, Sabine Bellstedt

Faculty Publications

We investigate the dark matter density profile of the massive elliptical galaxy, NGC 1407, by constructing spherically symmetric Jeans models of its field star and globular cluster systems. Two major challenges in such models are the degeneracy between the stellar mass and the dark matter halo profiles, and the degeneracy between the orbital anisotropy of the tracer population and the total mass causing the observed motions. We address the first issue by using new measurements of the mass-to-light ratio profile from stellar population constraints that include a radially varying initial mass function. To mitigate the mass–anisotropy degeneracy, we make ...


The Sluggs Survey: The Inner Dark Matter Density Slope Of The Massive Elliptical Galaxy Ngc 1407, Asher Wasserman, Aaron J. Romanowsky, Jean Brodie, Pieter G. van Dokkum, Charlie Conroy, Alexa Villaume, Duncan A. Forbes, Jay Strader, Adebusola B. Alabi, Sabine Bellstedt 2018 University of California, Santa Cruz

The Sluggs Survey: The Inner Dark Matter Density Slope Of The Massive Elliptical Galaxy Ngc 1407, Asher Wasserman, Aaron J. Romanowsky, Jean Brodie, Pieter G. Van Dokkum, Charlie Conroy, Alexa Villaume, Duncan A. Forbes, Jay Strader, Adebusola B. Alabi, Sabine Bellstedt

Aaron J. Romanowsky

We investigate the dark matter density profile of the massive elliptical galaxy, NGC 1407, by constructing spherically symmetric Jeans models of its field star and globular cluster systems. Two major challenges in such models are the degeneracy between the stellar mass and the dark matter halo profiles, and the degeneracy between the orbital anisotropy of the tracer population and the total mass causing the observed motions. We address the first issue by using new measurements of the mass-to-light ratio profile from stellar population constraints that include a radially varying initial mass function. To mitigate the mass–anisotropy degeneracy, we make ...


A Deficit Of Dark Matter From Jeans Modeling Of The Ultra-Diffuse Galaxy Ngc 1052-Df2, Asher Wasserman, Aaron Romanowsky, Jean Brodie, Pieter van Dokkum, Charlie Conroy, Roberto Abraham, Yotam Cohen, Shany Danieli 2018 University of California, Santa Cruz

A Deficit Of Dark Matter From Jeans Modeling Of The Ultra-Diffuse Galaxy Ngc 1052-Df2, Asher Wasserman, Aaron Romanowsky, Jean Brodie, Pieter Van Dokkum, Charlie Conroy, Roberto Abraham, Yotam Cohen, Shany Danieli

Faculty Publications

The discovery of the ultra-diffuse galaxy NGC 1052-DF2 and its peculiar population of star clusters has raised new questions about the connections between galaxies and dark matter (DM) halos at the extremes of galaxy formation. In light of debates over the measured velocity dispersion of its star clusters and the associated mass estimate, we constrain mass models of DF2 using its observed kinematics with a range of priors on the halo mass. Models in which the galaxy obeys a standard stellar-halo mass relation are in tension with the data and also require a large central density core. Better fits are ...


A Deficit Of Dark Matter From Jeans Modeling Of The Ultra-Diffuse Galaxy Ngc 1052-Df2, Asher Wasserman, Aaron J. Romanowsky, Jean Brodie, Pieter van Dokkum, Charlie Conroy, Roberto Abraham, Yotam Cohen, Shany Danieli 2018 University of California, Santa Cruz

A Deficit Of Dark Matter From Jeans Modeling Of The Ultra-Diffuse Galaxy Ngc 1052-Df2, Asher Wasserman, Aaron J. Romanowsky, Jean Brodie, Pieter Van Dokkum, Charlie Conroy, Roberto Abraham, Yotam Cohen, Shany Danieli

Aaron J. Romanowsky

The discovery of the ultra-diffuse galaxy NGC 1052-DF2 and its peculiar population of star clusters has raised new questions about the connections between galaxies and dark matter (DM) halos at the extremes of galaxy formation. In light of debates over the measured velocity dispersion of its star clusters and the associated mass estimate, we constrain mass models of DF2 using its observed kinematics with a range of priors on the halo mass. Models in which the galaxy obeys a standard stellar-halo mass relation are in tension with the data and also require a large central density core. Better fits are ...


Erratum: The Sluggs Survey: A Comparison Of Total-Mass Profiles Of Early-Type Galaxies From Observations And Cosmological Simulations, To ∼4 Effective Radii, Sabine Bellstedt, Duncan Forbes, Aaron Romanowsky, Rhea-Silvia Remus, Adam Stevens, Jean Brodie, Adriano Poci, Richard McDermid, Adebusola Alabi, Leonie Chevalier, Caitlin Adams, Anna Ferré-Mateu, Asher Wasserman, Viraj Pandya 2018 Swinburne University of Technology

Erratum: The Sluggs Survey: A Comparison Of Total-Mass Profiles Of Early-Type Galaxies From Observations And Cosmological Simulations, To ∼4 Effective Radii, Sabine Bellstedt, Duncan Forbes, Aaron Romanowsky, Rhea-Silvia Remus, Adam Stevens, Jean Brodie, Adriano Poci, Richard Mcdermid, Adebusola Alabi, Leonie Chevalier, Caitlin Adams, Anna Ferré-Mateu, Asher Wasserman, Viraj Pandya

Faculty Publications

This is an erratum to the paper “The SLUGGS Survey: A comparison of total-mass profiles of early-type galaxies from observations and cosmological simulations, to ∼4 effective radii” that was published in 2018, MNRAS, 476, 4543, which we refer to as the original paper.


Erratum: The Sluggs Survey: A Comparison Of Total-Mass Profiles Of Early-Type Galaxies From Observations And Cosmological Simulations, To ∼4 Effective Radii, Sabine Bellstedt, Duncan A. Forbes, Aaron J. Romanowsky, Rhea-Silvia Remus, Adam R H Stevens, Jean P. Brodie, Adriano Poci, Richard McDermid, Adebusola B. Alabi, Leonie Chevalier, Caitlin Adams, Anna Ferré-Mateu, Asher Wasserman, Viraj Pandya 2018 Swinburne University of Technology

Erratum: The Sluggs Survey: A Comparison Of Total-Mass Profiles Of Early-Type Galaxies From Observations And Cosmological Simulations, To ∼4 Effective Radii, Sabine Bellstedt, Duncan A. Forbes, Aaron J. Romanowsky, Rhea-Silvia Remus, Adam R H Stevens, Jean P. Brodie, Adriano Poci, Richard Mcdermid, Adebusola B. Alabi, Leonie Chevalier, Caitlin Adams, Anna Ferré-Mateu, Asher Wasserman, Viraj Pandya

Aaron J. Romanowsky

This is an erratum to the paper “The SLUGGS Survey: A comparison of total-mass profiles of early-type galaxies from observations and cosmological simulations, to ∼4 effective radii” that was published in 2018, MNRAS, 476, 4543, which we refer to as the original paper.


Bayesian Hierarchical Modelling Of Initial-Final Mass Relations Across Star Clusters, Shijing Si, David A. van Dyk, Ted von Hippel, Elliot Robinson, Elizabeth Jeffery, David C. Stenning 2018 Imperial College London

Bayesian Hierarchical Modelling Of Initial-Final Mass Relations Across Star Clusters, Shijing Si, David A. Van Dyk, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, David C. Stenning

Publications

The initial-final mass relation (IFMR) of white dwarfs (WDs) plays an important role in stellar evolution. To derive precise estimates of IFMRs and explore how they may vary among star clusters, we propose a Bayesian hierarchical model that pools photometric data from multiple star clusters. After performing a simulation study to show the benefits of the Bayesian hierarchical model, we apply this model to five star clusters: the Hyades, M67, NGC 188, NGC 2168, and NGC 2477, leading to reasonable and consistent estimates of IFMRs for these clusters. We illustrate how a cluster-specific analysis of NGC 188 using its own ...


A 3.5 Million Solar Masses Black Hole In The Centre Of The Ultracompact Dwarf Galaxy Fornax Ucd3, Anton Afanasiev, Igor Chilingarian, Steffen Mieske, Karina Voggel, Arianna Picotti, Michael Hilker, Anil Seth, Nadine Neumayer, Matthias Frank, Aaron Romanowsky, George Hau, Holger Baumgardt, Christopher Ahn, Jay Strader, Mark den Brok, Richard McDermid, Lee Spitler, Jean Brodie, Jonelle Walsh 2018 Moscow State University

A 3.5 Million Solar Masses Black Hole In The Centre Of The Ultracompact Dwarf Galaxy Fornax Ucd3, Anton Afanasiev, Igor Chilingarian, Steffen Mieske, Karina Voggel, Arianna Picotti, Michael Hilker, Anil Seth, Nadine Neumayer, Matthias Frank, Aaron Romanowsky, George Hau, Holger Baumgardt, Christopher Ahn, Jay Strader, Mark Den Brok, Richard Mcdermid, Lee Spitler, Jean Brodie, Jonelle Walsh

Faculty Publications

The origin of ultracompact dwarfs (UCDs), a class of compact stellar systems discovered two decades ago, still remains a matter of debate. Recent discoveries of central supermassive black holes in UCDs likely inherited from their massive progenitor galaxies provide support for the tidal stripping hypothesis. At the same time, on statistical grounds, some massive UCDs might be representatives of the high luminosity tail of the globular cluster luminosity function. Here we present a detection of a 3.3+1.4−1.2×106M⊙ black hole (1σ uncertainty) in the centre of the UCD3 galaxy in the Fornax cluster, which corresponds ...


A 3.5 Million Solar Masses Black Hole In The Centre Of The Ultracompact Dwarf Galaxy Fornax Ucd3, Anton V. Afanasiev, Igor V. Chilingarian, Steffen Mieske, Karina T. Voggel, Arianna Picotti, Michael Hilker, Anil Seth, Nadine Neumayer, Matthias Frank, Aaron J. Romanowsky, George Hau, Holger Baumgardt, Christopher P. Ahn, Jay Strader, Mark den Brok, Richard McDermid, Lee R. Spitler, Jean P. Brodie, Jonelle L. Walsh 2018 Moscow State University

A 3.5 Million Solar Masses Black Hole In The Centre Of The Ultracompact Dwarf Galaxy Fornax Ucd3, Anton V. Afanasiev, Igor V. Chilingarian, Steffen Mieske, Karina T. Voggel, Arianna Picotti, Michael Hilker, Anil Seth, Nadine Neumayer, Matthias Frank, Aaron J. Romanowsky, George Hau, Holger Baumgardt, Christopher P. Ahn, Jay Strader, Mark Den Brok, Richard Mcdermid, Lee R. Spitler, Jean P. Brodie, Jonelle L. Walsh

Aaron J. Romanowsky

The origin of ultracompact dwarfs (UCDs), a class of compact stellar systems discovered two decades ago, still remains a matter of debate. Recent discoveries of central supermassive black holes in UCDs likely inherited from their massive progenitor galaxies provide support for the tidal stripping hypothesis. At the same time, on statistical grounds, some massive UCDs might be representatives of the high luminosity tail of the globular cluster luminosity function. Here we present a detection of a 3.3+1.4−1.2×106M⊙ black hole (1σ uncertainty) in the centre of the UCD3 galaxy in the Fornax cluster, which corresponds ...


How Many Quasars Have Extremely High Velocity Outflows?, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo 2018 Humboldt State University

How Many Quasars Have Extremely High Velocity Outflows?, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University

No abstract provided.


Searching For A Connection Between Radio Emission And Uv/Optical Absorption In Quasars, Sean S. Haas, Carla P. Quintero, Paola Rodriguez Hidalgo 2018 Humboldt State University

Searching For A Connection Between Radio Emission And Uv/Optical Absorption In Quasars, Sean S. Haas, Carla P. Quintero, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University

No abstract provided.


Contribution Of Hi-Bearing Ultra-Diffuse Galaxies To The Cosmic Number Density Of Galaxies, M. Jones, E. Papastergis, V. Pandya, L. Leisman, Aaron J. Romanowsky, L. Yung, R. Somerville, E. Adams 2018 Instituto de Astrofísica de Andalucía

Contribution Of Hi-Bearing Ultra-Diffuse Galaxies To The Cosmic Number Density Of Galaxies, M. Jones, E. Papastergis, V. Pandya, L. Leisman, Aaron J. Romanowsky, L. Yung, R. Somerville, E. Adams

Faculty Publications

We estimate the cosmic number density of the recently identified class of HI-bearing ultra-diffuse sources (HUDs) based on the completeness limits of the ALFALFA survey. These objects have HI masses approximately in the range 8.5 < logMHI∕M⊙ < 9.5, average r-band surface brightnesses fainter than 24 mag arcsec−2, half-light radii greater than 1.5 kpc, and are separated from neighbours by at least 350 kpc. In this work we demonstrate that they contribute at most ~6% of the population of HI-bearing dwarfs detected by ALFALFA (with similar HI masses), have a total cosmic number density of (1.5 ± 0 ...


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