Mariana Lazarova

PhD, University of California-Riverside, 2012
Area of Study: Physics

MS, University of California-Riverside, 2007
Area of Study: Physics

BS, Sweet Briar College, 2005
Area of Study: Physics

Associate Professor, University of Northern Colorado
Physics & Astronomy (2023 – Present)

Assistant Professor, University of Northern Colorado
(2018-present)

Assistant Professor, University of Nebraska at Kearney
(2014-2018)

Visiting Assistant Professor, Colorado College
(2013-2014)

Visiting Assistant Professor, Pomona College
(2012-2013)

Graduate Research/Teaching Assistant, University of California-Riverside
(2005 – 2012)

Radio Properties of LoBAL quasars

The main focus on my research currently is a study of the radio emission in LoBAL quasars. It’s an extension on my general research focus into a new wavelength regime – radio observations of quasars – which I don’t have current expertise on, so it’s a steep learning curve. In my current work, I’m using publicly available archival observations conducted with the Very Large Array (VLA, a network of radio telescopes located in Socorro, NM, and operated by the National Radio Astronomy Observatory) to study the radio emission of a rare type of quasars known as Low-ionization Broad Absorption Line quasars (LoBALs). Very little is known about their radio properties because, since their discovery, they were believed to be radio-quite objects, with insignificant emission at radio wavelengths. The data available in the VLA archive can be used to quantify detection fractions and low-resolution morphology in a single bandpass (2-4 GHz), but for the upcoming publication, we need to obtain new, targeted observations with the VLA in 4 bands to calculate spectral slopes which give clues to the source of the radio emission. I have a hypothesis that the fast outflows observed in LoBAL quasars are young, emerging jets observed in the radio, and the objects are in dramatically fast transition from high- to low- accretion state. In addition to testing that idea, the radio morphologies of LoBALs have not been studied in any significantly large samples due to their rarity, and this work will contribute to the limited research on this.

My efforts in the last few months have been toward an observing proposal for the VLA – assembling a team of experts, defining the sample, getting archival data, analyzing the radio images, and learning about radio emission in the literature. I have finally assembled a team of experts to work on writing the VLA observing proposal, which is due in 31 July 2025. One of my collaborators is radio astronomer Dr. Grant Denn, a professor at the Metropolitan State University of Denver, with whom I have weekly research progress meetings on Zoom.

On Oct 11, 2024, I presented our preliminary results of this work with a poster entitled “VLASS reveals high incidence of radio detections and extreme morphologies in a sample of low-z LoBAL quasars” at the 2024 Meeting of the American Physical Society Four Corners Section at the Northern Arizona University, Flagstaff, AZ.

In the Fall 2024, undergraduate student Michelle Weiss’25 started working with me (in PHYS 370) on a tangential project investigating the biases in sample selection of LoBALs by cross-matching the three available catalogues. She continues work on the project in Spring 2025 for her PHYS 470: Research II course.

Winds of Change: Investigating Variability in the Spectra of Quasars with Outflows Using Data from the Sloan Digital Sky Survey

I am working with UNC undergraduate student Michael Carrasco (Physics major) on a project investigating variability in the optical spectra of a small sample of 22 LoBAL quasars. We are using archival data from the Sloan Digital Sky Survey (https://www.sdss.org/) to obtain spectra from different Data Releases (DRs) of the survey, hence, observations spaced in time from 2003 until 2018. We will be tracking variability in the BAL (outflow) troughs, as well as in the underlying continuum emission. In our literature research, we discovered only one other paper that reports on the variability in LoBAL quasars (Vivek, et al., 2014). Given the scarcity of research into the topic, our work will greatly contribute to understanding the nature of LoBALs. We have already discovered one object that exhibits extreme variability in the continuum by a factor of two, but further modeling is needed to see if this is the case for the line absorptions and for other objects. This is work in progress that started Fall 2024 as an independent student project and is still on-going during the Spring 2025 semester as Michael’s independent research.

I supported Michael in applying for an OUR grant in the Fall 2024, but his proposal was not funded.

Areas of Interest

Observational Astronomy, The role of Active Galactic Nuclei (AGN) in galaxy evolution, Quasar host galaxies, Broad Absorption Line (BAL) quasars, Blackhole scaling relations, AGN-driven feedback, AGN variability

• “The Nature of LoBAL QSOs: II. HST/WFC3 Observations Reveal Host Galaxies Dominated by Mergers”
  Lazarova, M., et al., 2023, The Astrophysical Journal, 949, 69
• “I’m Still Standing” 
Lazarova, M., 2021, The Physics Teacher, 59, 506.
• “Acceleration of Coronal Mass Ejection Plasma in the Low Corona as Measured by the Citizen CATE Experiment” Penn, M., et al. (including Lazarova, M.) 2019, The Astronomical Society of the Pacific, 132, 1007
• “Medium-resolution Optical and Near-infrared Spectral Atlas of 16 2MASS-selected NIR-red Active Galactic Nuclei at z ∼ 0.3” Kim, D., et al.(including Lazarova, M.) 2018, ApJS, 238, 37
• “Studying the spatially-resolved [OIII] 5007Å emission-line profile in a sample of ∼80 local active galaxies: a surrogate for s” Bennert, V., et al. (including Lazarova, M.) 2018, MNRAS, 481, 138
• “The Lick AGN Monitoring Project 2011: Dynamic Modeling of the Broad Lline Region” Williams, P., et al. (including Lazarova, M.) 2018, ApJ, 866, 75
• “Stability of the Broad Line Region Geometry and Dynamics in ARP 151 Over Seven Years” Pancoast, A., et al. (including Lazarova, M.) 2018, ApJ, 856, 108
• “Broad H-beta Emission-Line Variability in a Sample of 102 Local Active Galaxies” Runco, J, Cosens, M, Bennert, V., Scott, B., Komossa, S., Malkan, M., Lazarova, M., Auger, M., Treu, T., Park, D., 2016, ApJ, 821, 33
• “VizieR Online Data Catalog: Broad Hb emission line in 102 Seyfert galaxies (Runco+, 2016)” Runco, J., et al. (including Lazarova, M.), ONLINE data catalogue for 2016, ApJS, 821, 33
• “The Lick AGN Monitoring Project 2011: Spectroscopic Campaign and Emission-line Light Curves” Barth, A., et al. (including Lazarova, M.), 2015, ApJSS, 217, 26
• “VizieR Online Data Catalog: Lick AGN monitoring 2011: light curves (Barth+, 2015)” Barth, A., et al. (including Lazarova, M.), ONLINE data catalogue for 2015, ApJS, 217, 26
• “The Lick AGN Monitoring Project 2011: FeII Reverberation from the Outer Broad Line Region” Barth, A., et al. (including Lazarova, M.), 2013, ApJ, 769, 128
• “The Nature of LoBAL QSOs: I. SEDs and Mid-infrared Spectral Properties” Lazarova, M., Canalizo, G., Lacy, M., & Sajina, A. 2012, ApJ, 755, 29
• “Probing the M-sigma Relation in the Non-Local Universe Using Red QSOs” Canalizo, G., Wold, M., Hiner, K., Lazarova, M., Lacy, M., & Aylor, K. 2012, ApJ, 760, 38
• “The Lick AGN Monitoring Project 2011: Dynamical Modeling of the Broad Emission Line Region in Mrk 50” Pancoast, A., et al. (including Lazarova), 2012, ApJ, 754, 49
• “The Lick AGN Monitoring Project 2011: Reverberation Mapping of Markarian 50” Barth, A., et al. (including Lazarova), 2011, ApJL, 743, 4
• “Infrared and Optical Properties of Low-z Low-Ionization Broad Absorption Line QSOs” Lazarova & Canalizo, 2009, ASPC, 408, 288
• Proceeding of “The Starburst – AGN Connection Conference”, 27-31 October 2008, Shanghai, China

Legend to Journal abbreviations:
ApJL = The Astrophysical Journal Letters
ApJ = The Astrophysical Journal
ApJS = The Astrophysical Journal Supplement Series
ASPC = Astronomical Society of the Pacific Conference Series
MNRAS = Monthly Notices of the Royal Astronomical Society