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Dark matter

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Full-Text Articles in Physical Sciences and Mathematics

Axion Dark Matter With Not Quite Black Hole Domination, Ufuk Aydemi̇r Jun 2024

Axion Dark Matter With Not Quite Black Hole Domination, Ufuk Aydemi̇r

Turkish Journal of Physics

No abstract provided.


Low Fine-Tuning With Heavy Higgsinos In Yukawa Unified Susy Guts, Cem Salih Ün Feb 2024

Low Fine-Tuning With Heavy Higgsinos In Yukawa Unified Susy Guts, Cem Salih Ün

Turkish Journal of Physics

The work presented considers a class of minimally constructed Yukawa unified SUSY GUTs - NUHM2 - and explores their implications when their soft supersymmetry breaking Lagrangian is generalized by the nonholomorphic terms which provide extra contributions to the Higgsino mass and couple the supersymmetric scalar fields to the wrong Higgs doublets. With such a simple extension, it can be found several regions with interesting implications which cannot be realized in the usual restricted models. It is observed that the Yukawa unification solutions can be compatible with a relatively light mass spectrum and acceptable low fine-tuning measurements. In the restricted models …


Radon Plate-Out And The Effects Of Airflow And Electric Charge For Dark Matter Experiments, Faith Fang Jan 2024

Radon Plate-Out And The Effects Of Airflow And Electric Charge For Dark Matter Experiments, Faith Fang

SMU Journal of Undergraduate Research

The Cryogenic Dark Matter Search (SuperCDMS) is an international collaboration designed to search for and detect dark matter particles, which make up ~85% of the matter in the universe. The plate-out, or deposition of naturally occurring radioactive decay byproducts onto surfaces, can create backgrounds that interfere with dark matter detection experiments. In the first series of these experiments, we analyze the amount of radon progeny, 214Pb and 214Bi, that plate-out on polycarbonate samples while controlling factors such as electric charge and airflow. These samples are exposed to radon-spiked nitrogen gas in a polycarbonate wind tunnel to simulate plate-out conditions in …


Buzzard To Cardinal: Improved Mock Catalogs For Large Galaxy Surveys, Chun-Hao To, Joseph Derose, Risa H. Wechsler, Eli Rykoff, Hao-Yi Wu, Susmita Adhikari, Elisabeth Krause, Eduardo Rozo, David H. Weinberg Jan 2024

Buzzard To Cardinal: Improved Mock Catalogs For Large Galaxy Surveys, Chun-Hao To, Joseph Derose, Risa H. Wechsler, Eli Rykoff, Hao-Yi Wu, Susmita Adhikari, Elisabeth Krause, Eduardo Rozo, David H. Weinberg

Physics Faculty Publications and Presentations

We present the Cardinal mock galaxy catalogs, a new version of the Buzzard simulation that has been updated to support ongoing and future cosmological surveys, including the Dark Energy Survey (DES), DESI, and LSST. These catalogs are based on a one-quarter sky simulation populated with galaxies out to a redshift of z = 2.35 to a depth of mr = 27. Compared to the Buzzard mocks, the Cardinal mocks include an updated subhalo abundance matching model that considers orphan galaxies and includes mass-dependent scatter between galaxy luminosity and halo properties. This model can simultaneously fit galaxy clustering and group–galaxy …


How Should Recent Creationists Respond To Dark Matter And Dark Energy?, Danny R. Faulkner Dec 2023

How Should Recent Creationists Respond To Dark Matter And Dark Energy?, Danny R. Faulkner

Proceedings of the International Conference on Creationism

Astronomers and cosmologists largely accept the reality of dark matter and dark energy. However, many recent creationists oppose both dark matter and dark energy, though it is not clear why. I propose a review of the evidence for dark matter and dark energy, a survey of creationists’ responses to both, and recommendations of how we ought to view dark matter and dark energy.

There are three lines of evidence for dark matter:

  1. Rotation curves of spiral galaxies
  2. Dispersion velocities of galaxy clusters
  3. Gravitational lensing of distant galaxies and quasars by closer galaxy clusters

The evidence for dark matter goes back …


The Influence Of Subhaloes On Host Halo Properties, Lorena Mezini, Catherine E. Fielder, Andrew R. Zentner, Yao-Yuan Mao, Kuan Wang, Hao-Yi Wu Dec 2023

The Influence Of Subhaloes On Host Halo Properties, Lorena Mezini, Catherine E. Fielder, Andrew R. Zentner, Yao-Yuan Mao, Kuan Wang, Hao-Yi Wu

Physics Faculty Publications and Presentations

Within the ΛCDM cosmology, dark matter haloes are composed of both a smooth component and a population of smaller gravitationally bound subhaloes. These components are often treated as a single halo when properties, such as density profiles, are extracted from simulations. Recent work has shown that density profiles change substantially when subhalo mass is excluded. In this paper, we expand on this result by analysing three specific host halo properties – concentration (cNFW), spin (λB), and shape (c/a) – when calculated only from the smooth component of the halo. This analysis …


Search For Evidence Of Baryogenesis And Dark Matter In B+→Ψd+P Decays At Babar, J. P. Lees, V. Poireau, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, E. A. Kravchenko, Milind Purohit, Et. Al. Nov 2023

Search For Evidence Of Baryogenesis And Dark Matter In B+→Ψd+P Decays At Babar, J. P. Lees, V. Poireau, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, E. A. Kravchenko, Milind Purohit, Et. Al.

Faculty Publications

A new dark sector antibaryon, denoted ψD, could be produced in decays of B mesons. This Letter presents a search for B+ψD+p (and the charge conjugate) decays in e+e annihilations at 10.58 GeV, using data collected in the BABAR experiment. Data corresponding to an integrated luminosity of 398 fb−1 are analyzed. No evidence for a signal is observed. Branching fraction upper limits in the range from 10−7–10−5 are obtained at 90% confidence level for masses of 1.0<D< 4.3 GeV/c2. The result is also reinterpreted to provide …


Understanding Quantum Field Theory And Standard Model To Explore Beyond Standard Model Physics, Alize Sucsuzer May 2023

Understanding Quantum Field Theory And Standard Model To Explore Beyond Standard Model Physics, Alize Sucsuzer

Honors Program Theses and Projects

Motivated by the goal of participating in astroparticle physics research in graduate school, we aimed to understand the Standard Model of particle physics and the Feynman diagrams through which particle interactions are described, so that we could learn about the properties of certain astroparticles. The axiomatic principle that governs fundamental physics is manifest covariance, implying that the mathematical forms of the physical laws are the same to all observers. Maintaining covariance requires 4-vector representation using group theoretical techniques based on symmetries, as well as a transition from single-particle quantum physics to many-particle quantum field theory (QFT). The Standard Model of …


Sensitivity Of The Cupid Experiment To Bragg-Primakoff Conversion Of Solar Axions And Alps, Kevin P. Wilson Apr 2023

Sensitivity Of The Cupid Experiment To Bragg-Primakoff Conversion Of Solar Axions And Alps, Kevin P. Wilson

Theses and Dissertations

The author reports in this dissertation on the application of a technique to use bolometer detector arrays, such as those of the CUORE experiment and its proposed upgrade CUPID, to search for 14.4 keV Solar axions arising from an M1 nuclear transition of thermally excited 57Fe in the Solar core. Density functional theory calculations performed using QU A N T U M ESPRESSO for Li2MoO4 enable the computation of a time-dependent axionto-photon conversion rate in the bolometer crystals. These calculations predict that the proposed CUPID detector will be sensitive to Solar axions or axion-like particles that …


Weak Gravitational Lensing Analysis In Two Superclusters Of Galaxies, Sarah B. Rice Dec 2022

Weak Gravitational Lensing Analysis In Two Superclusters Of Galaxies, Sarah B. Rice

Electronic Theses and Dissertations

Observations of the Universe on very large scales have shown it to be filled with galaxy clusters and superclusters connected by walls and filaments of galaxies, with vast areas mostly devoid of luminous matter separating them. It is widely accepted that the amount of luminous matter does not provide the mass needed to hold galaxies and galaxy clusters together, and the nature of the missing "dark matter" is one of the most prominent astrophysical mysteries today. Since dark matter interacts with luminous matter gravitationally, it stands to reason that dark matter might organize itself in a similar manner to luminous …


Dirac Dark Matter, Neutrino Masses, And Dark Baryogenesis, Diego Restrepo, Andrès Rivera, Walter Tangarife Sep 2022

Dirac Dark Matter, Neutrino Masses, And Dark Baryogenesis, Diego Restrepo, Andrès Rivera, Walter Tangarife

Physics: Faculty Publications and Other Works

We present a gauged baryon number model as an example of models where all new fermions required to cancel out the anomalies help to solve phenomenological problems of the standard model (SM). Dark fermion doublets, along with the isosinglet charged fermions, in conjunction with a set of SM-singlet fermions, participate in the generation of small neutrino masses through the Dirac-dark Zee mechanism. The other SM-singlets explain the dark matter in the Universe, while their coupling to an inert singlet scalar is the source of the CP violation. In the presence of a strong first-order electroweak phase transition, this “dark” CP …


Search For A Dark Leptophilic Scalar Produced In Association With Taupair In Electron-Positron Annihilation At Center-Of-Mass Energies Near 10.58 Gev., Diptaparna Biswas Aug 2022

Search For A Dark Leptophilic Scalar Produced In Association With Taupair In Electron-Positron Annihilation At Center-Of-Mass Energies Near 10.58 Gev., Diptaparna Biswas

Electronic Theses and Dissertations

Dark matter is believed to be a form of matter which seemingly accounts for approximately 85% of the matter in the universe and about 27% of its total mass–energy density. It doesn't participate in electromagnetic interaction, i.e. doesn't interact with light. Consequently, we cannot see it using optical or radio telescope and hence the name dark matter. However, it participates in gravitational interaction, and we hypothesize its existence based on a variety of astrophysical observations, including gravitational effects, that cannot be explained by the accepted theories of gravity unless we account for more matter than can be perceived through electromagnetic …


Neutron Stars With Baryon Number Violation, Probing Dark Sectors, Jeffrey M. Berryman, Susan Gardner, Mohammadreza Zakeri Mar 2022

Neutron Stars With Baryon Number Violation, Probing Dark Sectors, Jeffrey M. Berryman, Susan Gardner, Mohammadreza Zakeri

Physics and Astronomy Faculty Publications

The neutron lifetime anomaly has been used to motivate the introduction of new physics with hidden-sector particles coupled to baryon number, and on which neutron stars provide powerful constraints. Although the neutron lifetime anomaly may eventually prove to be of mundane origin, we use it as motivation for a broader review of the ways that baryon number violation, be it real or apparent, and dark sectors can intertwine and how neutron star observables, both present and future, can constrain them.


Exploiting Non-Linear Scales In Galaxy–Galaxy Lensing And Galaxy Clustering: A Forecast For The Dark Energy Survey, Andrés N. Salcedo, David H. Weinberg, Hao-Yi Wu, Benjamin D. Wibking Mar 2022

Exploiting Non-Linear Scales In Galaxy–Galaxy Lensing And Galaxy Clustering: A Forecast For The Dark Energy Survey, Andrés N. Salcedo, David H. Weinberg, Hao-Yi Wu, Benjamin D. Wibking

Physics Faculty Publications and Presentations

No abstract provided.


Updated Analysis Of An Unexpected Correlation Between Dark Matter And Galactic Ellipticity, D. M. Winters, Alexandre Deur, X. Zheng Jan 2022

Updated Analysis Of An Unexpected Correlation Between Dark Matter And Galactic Ellipticity, D. M. Winters, Alexandre Deur, X. Zheng

Physics Faculty Publications

We investigate a correlation between the dark matter content of elliptical galaxies and their ellipticity ϵ that was initially reported in 2014. We use new determinations of dark matter and ellipticities that are posterior to that time. Our data set consists of 237 elliptical galaxies passing a strict set of criteria that selects a homogeneous sample of typical elliptical galaxies. We find a relation between the mass-to-light ratio and ellipticity ϵ that is well fitted by M/L = (14.1 ± 5.4)ϵ, which agrees with the result reported in 2014. Our analysis includes 135 galaxies that were not in …


First Steps In The Small-Scale Structure Formation In The Universe: The Emergence Of Galaxies, Da Bi Jan 2022

First Steps In The Small-Scale Structure Formation In The Universe: The Emergence Of Galaxies, Da Bi

Theses and Dissertations--Physics and Astronomy

Galactic morphology in the contemporary universe results from the convergence of a long list of physical processes, not all of them yet fully understood and quantified. The universe exhibits a hierarchical structure: galaxies grow being immersed in dark matter (DM) halos, which in turn are fed by diffuse and filamentary accretion. I use a suite of very high-resolution zoom-in cosmological simulations of galaxies in order to study the assembly of galaxies at high redshifts, z ≥ 2, to quantify the role of environment and of the parent DM halos in this procss. My models have been chosen to lie within …


Acoustic Parameters As Discriminators Of Wall Events In Pico Dark Matter Search Data, Lucia Volkova Aug 2021

Acoustic Parameters As Discriminators Of Wall Events In Pico Dark Matter Search Data, Lucia Volkova

University Honors Program Senior Projects

Bubble chambers are one of several detector types that particle physicists use to search for the as-yet-undetected dark matter. The PICO collaboration – formed from the merger of the similar PICASSO and COUPP experiments – runs such a bubble detector using superheated fluorocarbons (with and without iodine). Bubbles that form along chamber walls exhibit different behavior than those which nucleate in the bulk of the target liquid due to shape distortions from the wall boundary; in previous analyses when searching for dark matter, these wall events have been cut from the data to control for the differing behavior using information …


Clustering And Halo Abundances In Early Dark Energy Cosmological Models, A. Klypin, V. Poulin, F. Prada, J. Primack, M. Kamionkowski, V. Avila-Reese, A. Rodriguez-Puebla, P. Behroozi, D. Hellinger, Tristan L. Smith Jun 2021

Clustering And Halo Abundances In Early Dark Energy Cosmological Models, A. Klypin, V. Poulin, F. Prada, J. Primack, M. Kamionkowski, V. Avila-Reese, A. Rodriguez-Puebla, P. Behroozi, D. Hellinger, Tristan L. Smith

Physics & Astronomy Faculty Works

Cold Dark Matter with cosmological constant (ΛCDM) cosmological models with early dark energy (EDE) have been proposed to resolve tensions between the Hubble constant H0=100h km ṡ−1Ṁpc−1 measured locally, giving h ≈ 0.73, and H0 deduced from Planck cosmic microwave background (CMB) and other early-Universe measurements plus ΛCDM, giving h ≈ 0.67. EDE models do this by adding a scalar field that temporarily adds dark energy equal to about 10 per cent of the cosmological energy density at the end of the radiation-dominated era at redshift z ∼ 3500. Here, we compare linear and non-linear predictions of a Planck-normalized ΛCDM …


The James Webb Space Telescope And Scientific Progress, Robert Astle Apr 2021

The James Webb Space Telescope And Scientific Progress, Robert Astle

Quest

Independent Research Paper

Research in progress for PHYS 2425: University Physics I

Faculty Mentor: Raji Kannampuzha, Ph.D.

The following paper represents research work done by students in University Physics 2425, the first half of a two-semester introductory course in physics. It is a calculus- based physics course, intended primarily for physics, chemistry, math, and engineering majors. Students are introduced to the concept of academic research by learning to ask research-focused questions and then use the library resources to pursue outside research to find answers. For this assignment, students are asked to investigate a physical science, biological science, or technology problem …


On The Halo-Mass And Radial Scale Dependence Of The Lensing Is Low Effect, J. U. Lange, A. Leauthaud, S. Singh, H. Guo, R. Zhou, Tristan L. Smith, F.-Y. Cyr-Racine Apr 2021

On The Halo-Mass And Radial Scale Dependence Of The Lensing Is Low Effect, J. U. Lange, A. Leauthaud, S. Singh, H. Guo, R. Zhou, Tristan L. Smith, F.-Y. Cyr-Racine

Physics & Astronomy Faculty Works

The canonical Lambda cold dark matter (ΛCDM) cosmological model makes precise predictions for the clustering and lensing properties of galaxies. It has been shown that the lensing amplitude of galaxies in the Baryon Oscillation Spectroscopic Survey (BOSS) is lower than expected given their clustering properties. We present new measurements and modelling of galaxies in the BOSS LOWZ sample. We focus on the radial and stellar mass dependence of the lensing amplitude mismatch. We find an amplitude mismatch of around 35 per cent when assuming ΛCDM with Planck Cosmological Microwave Background (CMB) constraints. This offset is independent of halo mass and …


The First Three Seconds: A Review Of Possible Expansion Histories Of The Early Universe, R. Allahverdi, M. A. Amin, A. Berlin, N. Bernal, C. T. Byrnes, M. S. Delos, A. L. Erickcek, M. Escudero, D. G. Figueroa, K. Freese, T. Harada, D. Hooper, D. I. Kaiser, T. Karwal, K. Kohri, G. Krnjaic, M. Lewicki, K. D. Lozanov, V. Poulin, K. Sinha, Tristan L. Smith, T. Takahashi, T. Tenkanen, J. Unwin, V. Vaskonen, S. Watson Jan 2021

The First Three Seconds: A Review Of Possible Expansion Histories Of The Early Universe, R. Allahverdi, M. A. Amin, A. Berlin, N. Bernal, C. T. Byrnes, M. S. Delos, A. L. Erickcek, M. Escudero, D. G. Figueroa, K. Freese, T. Harada, D. Hooper, D. I. Kaiser, T. Karwal, K. Kohri, G. Krnjaic, M. Lewicki, K. D. Lozanov, V. Poulin, K. Sinha, Tristan L. Smith, T. Takahashi, T. Tenkanen, J. Unwin, V. Vaskonen, S. Watson

Physics & Astronomy Faculty Works

It is commonly assumed that the energy density of the Universe was dominated by radiation between reheating after inflation and the onset of matter domination 54,000 years later. While the abundance of light elements indicates that the Universe was radiation dominated during Big Bang Nucleosynthesis (BBN), there is scant evidence that the Universe was radiation dominated prior to BBN. It is therefore possible that the cosmological history was more complicated, with deviations from the standard radiation domination during the earliest epochs. Indeed, several interesting proposals regarding various topics such as the generation of dark matter, matter-antimatter asymmetry, gravitational waves, primordial …


A Conceptual Model To Explain Dark Matter And Dark Energy, Jonathan Blackledge Dec 2020

A Conceptual Model To Explain Dark Matter And Dark Energy, Jonathan Blackledge

Articles

This paper considers a conceptual model that attempts to explain ‘Dark Matter’ and‘Dark Energy’. The model is based on considering a gravitational field to be the result of a mass (aHiggs field) scattering pre-existing cosmic background space-time waves or ‘Uber-waves’. The term‘Uber’ is used to denote an outstanding or supreme example of a particular kind of gravitationalwave with cosmic-scale wavelengths that are far in excess of those associated with the gravitationalwaves generated by accelerating masses. Such waves are taken to be the very lowest frequencycomponents associated with the spectrum of space-time waves generated by the ‘Big Bang’ andare supported by …


Dark Matter-Neutrino Interconversion At Coherent, Direct Detection, And The Early Universe, Nicholas Hurtado, Hana Mir, Ian M. Shoemaker, Eli Welch, Jason Wyenberg Jul 2020

Dark Matter-Neutrino Interconversion At Coherent, Direct Detection, And The Early Universe, Nicholas Hurtado, Hana Mir, Ian M. Shoemaker, Eli Welch, Jason Wyenberg

Faculty Work Comprehensive List

We study a dark matter (DM) model in which the dominant coupling to the standard model occurs through a neutrino-DM-scalar coupling. The new singlet scalar will generically have couplings to nuclei/electrons arising from renormalizable Higgs portal interactions. As a result, the DM particle X can convert into a neutrino via scattering on a target nucleus N: X+N→ν+N, leading to striking signatures at direct detection experiments. Similarly, DM can be produced in neutrino scattering events at neutrino experiments: ν+N→X+N, predicting spectral distortions at experiments such as COHERENT. Furthermore, the model allows for late kinetic decoupling of dark matter with implications for …


Origin Of Sterile Neutrino Dark Matter Via Secret Neutrino Interactions With Vector Bosons, Kevin J. Kelly, Manibrata Sen, Walter Tangarife, Yue Zhang Jun 2020

Origin Of Sterile Neutrino Dark Matter Via Secret Neutrino Interactions With Vector Bosons, Kevin J. Kelly, Manibrata Sen, Walter Tangarife, Yue Zhang

Physics: Faculty Publications and Other Works

Secret neutrino interactions can play an essential role in the origin of dark matter. We present an anatomy of production mechanisms for sterile neutrino dark matter, a keV-scale gauge-singlet fermion that mixes with active neutrinos, in the presence of a new vector boson mediating secret interactions among active neutrinos. We identify three regimes of the vector boson’s mass and coupling where it makes a distinct impact on dark matter production through the dispersion relations and/or scattering rates. We also analyze models with gauged Lμ−Lτ and B−L numbers which have a similar dark matter cosmology but different vector boson phenomenology. We …


Polarization Of Majorana Fermions In A Background Current, Lukas Karoly, David C. Latimer Jan 2020

Polarization Of Majorana Fermions In A Background Current, Lukas Karoly, David C. Latimer

Summer Research

A Majorana fermion is a particle which is its own antiparticle. As a consequence, their electromagnetic interactions are minimal. Because of this, they are a good candidate for dark matter with their sole static electromagnetic property being their anapole moment. The annihilation rate of Majorana fermions depends on whether their anapole moments are aligned (polarized) or anti-aligned (unpolarized). It is therefore important to understand how Majorana fermions polarize to better understand their annihilation rates. This can help us further understand and detect dark matter. Using Feynman diagrams, we calculate the cross section for the interaction between a Majorana fermion and …


Significance Of Gravitational Nonlinearities On The Dynamics Of Disk Galaxies, Alexandre Deur, Corey Sargent, Balša Terzić Jan 2020

Significance Of Gravitational Nonlinearities On The Dynamics Of Disk Galaxies, Alexandre Deur, Corey Sargent, Balša Terzić

Physics Faculty Publications

The discrepancy between the visible mass in galaxies or galaxy clusters and that inferred from their dynamics is well known. The prevailing solution to this problem is dark matter. Here we show that a different approach, one that conforms to both the current standard model of particle physics and general relativity (GR), explains the recently observed tight correlation between the galactic baryonic mass and the measured accelerations in the galaxy. Using direct calculations based on GR's Lagrangian and parameter-free galactic models, we show that the nonlinear effects of GR make baryonic matter alone sufficient to explain this observation. Our approach …


Precise Mass Determination Of Spt-Cl J2106-5844, The Most Massive Cluster At Z > 1, Jinhyub Kim, M. James Jee, Saul Perlmutter, Brian Hayden, David Rubin, Xiaosheng Huang, Greg Aldering, Jongwan Ko Dec 2019

Precise Mass Determination Of Spt-Cl J2106-5844, The Most Massive Cluster At Z > 1, Jinhyub Kim, M. James Jee, Saul Perlmutter, Brian Hayden, David Rubin, Xiaosheng Huang, Greg Aldering, Jongwan Ko

Physics and Astronomy

We present a detailed high-resolution weak-lensing study of SPT-CL J2106-5844 at z = 1.132, claimed to be the most massive system discovered at z > 1 in the South Pole Telescope Sunyaev–Zel'dovich survey. Based on the deep imaging data from the Advanced Camera for Surveys and Wide Field Camera 3 on board the Hubble Space Telescope, we find that the cluster mass distribution is asymmetric, composed of a main clump and a subclump ~640 kpc west thereof. The central clump is further resolved into two smaller northwestern and southeastern substructures separated by ~150 kpc. We show that this rather complex …


Dark Matter And No Dark Matter: On The Halo Mass Of Ngc 1052, Duncan Forbes, Adebusola Alabi, Jean Brodie, Aaron Romanowsky Nov 2019

Dark Matter And No Dark Matter: On The Halo Mass Of Ngc 1052, Duncan Forbes, Adebusola Alabi, Jean Brodie, Aaron Romanowsky

Faculty Publications

The NGC 1052 group, and in particular the discovery of two ultra-diffuse galaxies with very low internal velocity dispersions, has been the subject of much attention recently. Here we present radial velocities for a sample of 77 globular clusters associated with NGC 1052 obtained on the Keck telescope. Their mean velocity and velocity dispersion are consistent with that of the host galaxy. Using a simple tracer mass estimator, we infer the enclosed dynamical mass and dark matter fraction of NGC 1052. Extrapolating our measurements with a Navarro–Frenk–White (NFW) mass profile we infer a total halo mass of 6.2(±0.2) × 1012 …


Proper Motion Objects In The Hubble Deep Field, M. Kilic, Ted Von Hippel, Et Al. Aug 2019

Proper Motion Objects In The Hubble Deep Field, M. Kilic, Ted Von Hippel, Et Al.

Ted von Hippel

Using the deepest and finest resolution images of the universe acquired with the Hubble Space Telescope and a similar image taken 7 yr later for the Great Observatories Origins Deep Survey, we have derived proper motions for the point sources in the Hubble Deep Field–North. Two faint blue objects, HDF 2234 and HDF 3072, are found to display significant proper motion, 10:0 ± 2:5 and 15:5 ± 3:8 mas yr¯1. Photometric distances and tangential velocities for these stars are consistent with disk white dwarfs located at ~500 pc. The faint blue objects analyzed by Ibata et al. and Mendez & …


Search For Dwarf Emission Line Galaxies In Galaxy Voids, Christian D. Draper Aug 2019

Search For Dwarf Emission Line Galaxies In Galaxy Voids, Christian D. Draper

Theses and Dissertations

The population and formation of dwarf galaxies, Mr > −14, contain clues about the nature of dark matter. The best place to search for these dwarf galaxies without influence from nearby large galaxies is within galaxy voids, where no galaxies have yet been found. To search for this potential dwarf galaxy population we have developed and applied a new photometric technique. We use three redshifted Ha filters, designated Ha8, Ha12, and Ha16, along with the Sloan broadband filters, g', r', and i' to identify emission line galaxies. From the ratio of the object flux through the Ha filters, Ha12-Ha8 and Ha12-Ha16, …