Chance of Non-Nucleated Light Source Superposition on Ultra-Diffuse Galaxy Centers

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Chance of Non-Nucleated Light Source Superposition on Ultra-Diffuse Galaxy Centers Michaud, Max (School: University High School) This project sought to determine whether Dark Matter dominated galaxies are nucleated. In January of 2015, an article was published that sparked interest in the scientific community. The scientists noticed unusual qualities about 47 galaxies of ~1.5kpc in the Coma cluster, one of the two major clusters in the Coma supercluster. These galaxies display surprising dichotomies that exist among their distinguishing characteristics: they possess high volume while simultaneously having low metallicity, stellar formation rates, and energy radiation. Most resemble red sequence late-type galaxy analogues with low mass, suggesting that they are dark matter-dominated and therefor of great interest to the scientific community. Because of these properties, the 47 objects were made a new classification of galaxies: Ultra-Diffuse Galaxies (UDGs). This project analyzed 275 UDG images that were “the result of automated post processing of data from the Legacy Surveys, a three-band imaging survey covering 14,000 square degrees of the intergalactic sky.” 17 objects in the sample appeared to have nucleated centers, and the focus of this project became to understand if that were true. By first finding out the chance percentage of a superpositioned light source being anywhere on the image, the binomial distribution theorem was used to determine the likelihood of the galaxies identified with a central light source being actually nucleated. The data analysis demonstrated a 79% certainty that the 17 UDGs are nucleated, which is not enough to make the claim that every galaxy possessing a central light source within this project’s criteria is nucleated. Knowing whether or not these DM-dominated objects are nucleated would give insight into the nature of dark matter interactions with itself. Awards Won: University of Arizona: Renewal Tuition Scholarship .

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Formation of an Ultra-Diffuse Galaxy in the Stellar Filaments of NGC 3314A
A&A 652, L11 (2021) Astronomy https://doi.org/10.1051/0004-6361/202141086 & c ESO 2021 Astrophysics LETTER TO THE EDITOR Formation of an ultra-diffuse galaxy in the stellar filaments of NGC 3314A: Caught in the act? Enrichetta Iodice1 , Antonio La Marca1, Michael Hilker2, Michele Cantiello3, Giuseppe D’Ago4, Marco Gullieuszik5, Marina Rejkuba2, Magda Arnaboldi2, Marilena Spavone1, Chiara Spiniello6, Duncan A. Forbes7, Laura Greggio5, Roberto Rampazzo5, Steffen Mieske8, Maurizio Paolillo9, and Pietro Schipani1 1 INAF-Astronomical Observatory of Capodimonte, Salita Moiariello 16, 80131 Naples, Italy e-mail: [email protected] 2 European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei Muenchen, Germany 3 INAF-Astronomical Observatory of Abruzzo, Via Maggini, 64100 Teramo, Italy 4 Instituto de Astrofísica, Facultad de Fisica, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 7820436 Macul, Santiago, Chile 5 INAF-Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy 6 Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK 7 Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia 8 European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago, Chile 9 University of Naples “Federico II”, C.U. Monte Sant’Angelo, Via Cinthia, 80126 Naples, Italy Received 14 April 2021 / Accepted 9 July 2021 ABSTRACT The VEGAS imaging survey of the Hydra I cluster has revealed an extended network of stellar filaments to the south-west of the spiral galaxy NGC 3314A. Within these filaments, at a projected distance of ∼40 kpc from the galaxy, we discover an ultra-diffuse galaxy −2 (UDG) with a central surface brightness of µ0;g ∼ 26 mag arcsec and effective radius Re ∼ 3:8 kpc.
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