My research is focused on multiwavelength and multimessenger observations of astrpohysical transients. A complete list of my published projects can be found on either NASA ADS or Google Scholar.

Tidal Disruption Events

Tidal Disruption Events (TDEs) occur when a star passes too close to a supermassive black hole (SMBH), tearing the star apart as the external tidal forces overwhelm the stars internal binding energy. After the star is torn apart, the debris settles into an accretion disk and emits across the entire electromagnetic spectrum. With ~200 TDEs known to date, we are reaching an exciting time in the field where we can begin to draw population level conclusions. My research focuses on utilizing multiwavelength observations of TDEs to understand the physical processes dominating the emission mechanisms.

As part of this mission, I curated a catalog of multiwavelength TDE candidate photometry, called the Open mulTiwavelength Transient Even Repository (OTTER) is live! The goal of OTTER is to host a cleaned version of all public time domain photometry. The current dataset and codes are available at the OTTER github (Franz et al., 2026)

I am now also utilizing OTTER to explore the connection between Extreme Coronal Line Emitters (ECLEs) and TDEs: ECLEs are high ionization metal lines observed in the nucleus of galaxies, some of which are unambiguously associated with TDEs. We are using radio observations to probe the properties of these galaxies on sub-parsec scales to try to better understand why only some TDEs produce ECLs.

Gravitational Wave Follow-up:

Searching for electromagnetic counterparts to gravitational wave signals is essential for furthering our understanding of fundamental physics. Unfortunately, finding these counterparts is very difficult, making real-time, rapid, and automated analysis of new candidates essential.

As part of the Searches After Gravitational waves Using ARizona Observatories (SAGUARO) collaboration, I help search for and vet (or analyze) electromagnetic counterparts to gravitational waves. As part of this, I led a project and paper on the Type IIb Supernova 2025ulz, a potential counterpart to a gravitational wave event, that we show to be unlikely related (Franz et al., 2025).

We strive to make the complex vetting methods used as part of SAGUARO publicly accessible. To accomplish this, we are developing TROVE, a web application and API for real-time vetting of electromagnetic counterparts to multi-messenger events. This is closely related to the SAGUARO collaboration and will be essential support for optimizing community follow-up of poorl localized gravitational wave, neutrino, and high energy transients.

Highlighted Software & Codes

As part of research I also enjoy developing reusable codes to both reproduce my results and enable similar analyses in the future. All of the code for my projects is publicly available on my GitHub. Here are a few of my most relevant projects:

  • OTTER API
    A python package for interacing with the OTTER datasets that we recently published in the Journal of Open Source Software.

  • TROVE
    The TROVE repository hosts all of our open source code to build the Django application for the TROVE project.

  • syncfit
    A python package for fitting synchrotron radiation dominated spectral energy distributions with commonly used theoretical models. This package utilized multiple Bayesian Markov chain Monte Carlo tools to optimize the best model fit for the data in a high dimensional parameter space.

  • SAGUARO
    SAGUARO (Searches After Gravitational waves Using ARizona Observatories) is a multimessenger followup program for optical searches for multiwavelength counterparts to gravitational wave events. As part of this project, I work on the Target and Observation Management infrastructure for easily visualizing and triggering followup observations.

  • hepfile
    A software used to store so-called heterogeneous datasets, or data that does not fit into the typical MxN table, in a way that makes reading and writing fast.