Supernova origins explored through primordial black holes

Dr. Shing-Chi Leung, assistant professor of physics at SUNY Polytechnic Institute, has published the article " Primordial Black Hole Triggered Type Ia Supernovae II: Comparison with Supernova Remnants and Galactic Chemical Evolution " in The Astrophysical Journal . The paper was co-authored by SUNY Poly student Seth Walther, a senior majoring in electrical and computer engineering and applied mathematics with a minor in physics; Alexander Kusenko (UCLA); Ken'ichi Nomoto (Kavli IPMU, recipient of the 2026 Shaw Prize in Astronomy and the 2026 Gruber Cosmology Prize); and Tomoharu Suzuki (Chubu University).

Primordial black holes (PBHs) are hypothetical relics from the early universe. During the inflationary epoch, primordial fluctuations in matter density may have led to the formation of these black holes. PBHs are considered a potential candidate for dark matter , the invisible form of matter that accounts for most of the matter in the universe by mass. As PBHs travel through space, they may pass through stars.

Previous studies have shown that the intense tidal forces generated during a PBH's passage could trigger a white dwarf—the final evolutionary stage of a low-mass star—to explode as a type Ia supernova. Leung and his collaborators are investigating the dynamical, observational and chemical characteristics of supernovae produced through this newly proposed explosion mechanism.

In Paper I, " Primordial Black Hole Triggered Type Ia Supernovae I: Impact on Explosion Dynamics and Light Curves ," the team demonstrated that PBH-triggered explosions can produce type Ia supernovae that closely resemble those described in standard models. Furthermore, these supernovae can reproduce the empirical relationship used by cosmologists to measure cosmic distances and discover dark energy—a relationship whose physical origin remains incompletely understood. This finding suggests that PBH-triggered supernovae may already constitute a portion of the type Ia supernovae observed throughout the universe.

In Paper II, the team built on these findings by comparing its models with observations of supernova remnants, including Tycho, Kepler and 3C 397; nearby supernovae such as SN 2011fe and SN 2012cg; and stars within the Milky Way.

(Top panel) The isotopic mass fraction ratios [X/56Fe] for 06B-noKH-Z0, 06B-noKH-Z0002, 06B-noKH-Z002, and 06B-noKH-Z006. The horizontal lines refer to two times (upper line) and half (lower line) the solar values. (Bottom panel) Same as the top panel but for 06B-KH-Z0, 06B-KH-Z0002, 06B-KH-Z002, and 06B-KH-Z006. Credit: The Astrophysical Journal (2026). DOI: 10.3847/1538-4357/ae6db7

Their analysis showed that the PBH-triggered explosion channel can account for several observed characteristics of these objects. By examining radioactive isotopes such as nickel-56 and nickel-57, as well as stable elements including manganese and nickel, the researchers were able to constrain the masses and metallicities of the progenitor stars responsible for these supernovae and remnants.

The team also incorporated its supernova models into galactic chemical evolution simulations to investigate how this explosion channel contributes to the enrichment of elements throughout galaxies. Their results indicate that a nonzero fraction of PBH-triggered type Ia supernovae is needed to reproduce the chemical abundance patterns observed in Milky Way stars.

SUNY Poly student Seth Walther joined the project in summer 2024 through the Summer Undergraduate Research Program. As a co-author, he applied nucleosynthetic yields generated by Leung's models to galactic chemical evolution calculations, helping determine how successive generations of supernovae enrich galaxies with heavy elements over time.

"Being a part of physics research has advanced my knowledge of important industry standards in writing, presenting and coding, while also strengthening my ability to think critically and solve complex problems," Walther said.

"It has not only helped me secure internship opportunities but also allowed me to thrive in them because of the strong foundation I built through physics research. The background and knowledge I have gained translate well to real-world situations, and they also make for great conversation starters. I believe physics research is an excellent starting point for anyone interested in STEM fields because it prepares you for many of the challenges and opportunities the world will present."

"Our work suggests that some of the supernovae we observe may be the result of primordial black holes," Leung said. "Although we cannot directly observe these elusive objects, they leave behind important clues that allow us to investigate their properties."

He added, "I am also impressed by the tremendous progress Seth has made throughout this project. His performance demonstrates that undergraduate students are fully capable of conducting research at the level expected by the scientific community. With the launch of our ne…