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Effective supernova dust yields from rotating and non-rotating stellar progenitors

This study utilizes the GRASHrev model to quantify how reverse shocks affect dust survival in supernovae from rotating and non-rotating progenitors, revealing that while only a small fraction (up to ~5%) of initial dust mass survives—primarily as large amorphous carbon grains—supernovae can still effectively enrich the early interstellar medium with carbonaceous dust capable of explaining high-redshift extinction features.

Original authors: Koki Otaki, Raffaella Schneider, Luca Graziani, Alessandro Bonella, Stefania Marassi, Marco Limongi, Simone Bianchi

Published 2026-04-01

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CC BY 4.0

Original authors: Koki Otaki, Raffaella Schneider, Luca Graziani, Alessandro Bonella, Stefania Marassi, Marco Limongi, Simone Bianchi

Original paper licensed under CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/). ✨ This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer

The Big Picture: The Cosmic Dust Factory

Imagine the universe as a giant construction site. To build stars, planets, and eventually life, you need "bricks." In the early universe, these bricks are dust grains (tiny specks of solid matter like carbon or rock).

For a long time, astronomers thought Supernovae (exploding stars) were the main factories making these bricks. When a massive star dies, it explodes and scatters new dust into space.

But here's the catch: The explosion is so violent that it creates a "reverse shockwave." Think of it like a giant, invisible wall of wind blowing back into the explosion. This wall acts like a cosmic sandblaster. It doesn't just push the dust out; it smashes the delicate new bricks into even smaller, invisible dust, or vaporizes them completely before they can reach the rest of the galaxy.

This paper asks a simple question: How many of these "bricks" actually survive the sandblasting to become useful building blocks for the universe?

The Experiment: A Cosmic Simulation

The authors built a massive computer simulation to test this. They didn't just look at one type of star; they tested a whole "menu" of different stellar explosions:

Different Star Sizes: From small massive stars (13 times the Sun's mass) to giants (120 times the Sun's mass).
Different Spins: Some stars were spinning fast (like a figure skater), and some were spinning slowly (like a slow-turning top).
Different Environments: They simulated the explosion happening in three types of neighborhoods: a quiet, empty desert (low density), a busy city (medium density), and a crowded market (high density).

They used a model called GRASHrev to act as the "sandblaster," simulating how the reverse shockwave destroys the dust.

The Key Findings

1. The "Sandblaster" is Brutal

The results were harsh. In most cases, 95% to 99% of the newly formed dust gets destroyed by the reverse shock.

Analogy: Imagine a baker pulls a perfect, giant cake out of the oven. Immediately, a hurricane hits it. By the time the hurricane passes, 99% of the cake is gone, leaving only a few crumbs.
The Survivors: The only things that survive are the largest, toughest crumbs. Tiny, fragile grains (smaller than 10 nanometers) are vaporized instantly. Only the big, sturdy grains (larger than 10 nanometers) make it through.

2. The "Big Guys" Win

You might think the biggest stars make the most dust, but they also make the most fragile dust. However, the paper found a surprising twist:

The most massive stars (like the 120-solar-mass giants) actually produce the most surviving dust, even though they destroy a lot of it.
Why? Because the dust they make is made of Amorphous Carbon (basically soot). These carbon grains are like tough, hard rocks. They are naturally larger and stronger, so they can withstand the sandblasting better than the fragile silicate (rock) grains made by smaller stars.

3. Rotation Matters (The Spin Cycle)

The paper looked at whether a star's spin changes the outcome.

Spinning stars tend to mix their insides more, creating different chemical conditions.
Result: Spinning stars actually produced slightly more surviving dust in certain conditions compared to non-spinning ones. It's like spinning a salad; the ingredients get mixed differently, sometimes creating a more resilient mixture.

4. The Environment is Key

Where the star explodes matters a lot.

If a star explodes in a dense area (like a crowded city), the reverse shock is stronger, and more dust is destroyed.
If it explodes in a sparse area (like a desert), more dust survives.
The Sweet Spot: The best scenario for dust survival was a massive star exploding in a medium-density neighborhood. In this specific case, about 4% to 5% of the original dust survived.

Why Should We Care? (The "So What?")

You might ask, "If 95% of the dust is destroyed, why does this matter?"

Because 5% is enough to explain the universe we see today.

The Early Universe Mystery: Astronomers recently looked at galaxies that existed when the universe was very young (less than 1 billion years old). They found a lot of dust there, including a specific type of carbon dust that creates a "UV bump" (a specific way light is blocked).
The Connection: Before this paper, it was hard to explain how so much dust could exist so early. Other sources (like aging stars) take too long to form dust.
The Solution: This paper shows that even though the "sandblaster" destroys most of the dust, the massive, fast-spinning stars can still inject enough tough, carbon-rich dust into the galaxy in a very short time. This explains how the early universe got its "bricks" so quickly.

The Takeaway Analogy

Imagine the early universe is a construction site that needs to build a skyscraper overnight.

Old Theory: We thought the construction workers (stars) were too slow to get the job done.
New Theory (This Paper): The workers are actually very fast, but they have a very messy, destructive method. They throw bricks at the wall, but a giant wind machine (the reverse shock) blows 95% of them away.
The Result: Even with the wind machine, the workers are throwing out so many super-strong, reinforced bricks (carbon grains from massive stars) that they still manage to build the skyscraper before the sun comes up.

In short: Supernovae are messy, destructive, and wasteful, but they are still the most efficient way the early universe got the dust it needed to build stars and planets.

1. Problem Statement

Supernovae (SNe) are considered the primary sources of interstellar dust (ISD) in the early universe (high redshift, $z > 6$ ). However, a critical bottleneck exists: newly formed dust grains in SN ejecta are subjected to a reverse shock generated when the SN forward shock interacts with the surrounding Interstellar Medium (ISM). This reverse shock can thermally and non-thermally sputter, shatter, or vaporize a significant fraction of the dust before it is injected into the ISM.

While previous studies have estimated dust destruction, there remains uncertainty regarding:

The effective dust yields (mass actually surviving to enrich the ISM) across a wide grid of progenitor masses, metallicities, and rotation rates.
The impact of stellar rotation on dust survival, which alters progenitor evolution and ejecta composition.
The grain size distribution of surviving dust, which is crucial for understanding early galaxy extinction properties (e.g., the 2175 Å UV bump).

2. Methodology

The authors employed a multi-step modeling approach combining stellar evolution, dust nucleation, and hydrodynamic shock processing.

Stellar Progenitor Grid:
- Source: Models from Limongi & Chieffi (2018) computed using the FRANEC code.
- Parameters:
  - Progenitor Mass ( $M_*$ ): $13 - 120 \, M_\odot$ .
  - Metallicity ($[Fe/H] $):$ 0, -1, -2, -3$.
  - Rotation Velocity ( $v$ ): $0$ (non-rotating) and $300 \, \text{km s}^{-1}$ (rotating).
- Explosion Energy: Fixed at $1.2 \times 10^{51}$ erg.
Initial Dust Yields:
- Input data from Marassi et al. (2019), calculated using Classical Nucleation Theory.
- Grain Species: Amorphous Carbon (AC), Iron (Fe), Corundum ( $Al_2O_3$ ), Magnetite ( $Fe_3O_4$ ), Enstatite ( $MgSiO_3$ ), Forsterite ( $Mg_2SiO_4$ ), and Quartz ( $SiO_2$ ).
- Size Distribution: Log-normal or bimodal distributions depending on nucleation conditions.
Reverse Shock Processing (GRASHrev Model):
- Model: Used the GRASHrev model (Bocchio et al. 2016), which solves the hydrodynamics of the SN remnant expanding into a uniform ISM using the Truelove & McKee (1999) self-similar solution.
- Physics: Tracks dust destruction via:
  - Thermal Sputtering: Negligible in this context.
  - Non-thermal Sputtering: Dominant destruction mechanism (collisions with gas ions).
  - Shattering/Vaporization: Grain-grain collisions (sub-dominant due to low dust density).
  - Decoupling: Accounts for the velocity decoupling between gas and dust when the reverse shock passes.
- ISM Densities: Simulations run for three ambient densities: $n_{ISM} = 0.05, 0.5, \text{and } 5 \, \text{cm}^{-3}$ .

3. Key Contributions

Systematic Grid Analysis: First study to quantify effective dust yields across a comprehensive grid of progenitor masses ( $13-120 \, M_\odot$ ), metallicities, and rotation rates simultaneously.
Rotation Effects: Explicitly demonstrates how rotation-induced mixing alters ejecta composition (favoring silicates in low-mass stars, AC in high-mass) and how this influences dust survival.
Effective Yields Database: Provides a quantitative dataset of surviving dust mass, composition, and size distributions intended for use in chemical evolution models of high-redshift galaxies.

4. Key Results

A. Dust Survival Fractions

General Trend: The reverse shock is highly destructive. Only a small fraction of initially formed dust survives, typically $< 10\%$ .
Maximum Survival:
- Non-rotating: Max surviving mass $\simeq 0.02 \, M_\odot$ (from a $120 \, M_\odot$ progenitor at $[Fe/H]=0$ in $n_{ISM}=0.5 \, \text{cm}^{-3}$ ), representing $\simeq 4\%$ of initial mass.
- Rotating: Max surviving mass $\simeq 0.03 \, M_\odot$ (from a $120 \, M_\odot$ progenitor at $[Fe/H]=-1$), representing $\simeq 5\%$ of initial mass.
Density Dependence: Surviving dust mass decreases as ISM density increases.
Mass Dependence: Counter-intuitively, massive progenitors ( $>25-30 \, M_\odot$ ) often yield higher surviving dust masses than intermediate-mass stars ( $20-25 \, M_\odot$ ), despite the latter producing more total dust initially. This is because massive progenitors form larger grains that are more resistant to sputtering.

B. Grain Size and Composition

Size Resistance: Grains with initial radii $a \gtrsim 10 \, \text{nm}$ are significantly more resistant to destruction. Grains $< 10 \, \text{nm}$ are often completely destroyed.
Dominant Species: Amorphous Carbon (AC) dominates the surviving dust mass in most models because AC grains tend to form larger sizes initially.
Rotation Impact:
- Rotating models generally produce larger average grain sizes than non-rotating models.
- Rotation enhances silicate formation in low-mass progenitors but leads to AC dominance in massive ones.
Post-Shock Distribution: The reverse shock shifts the size distribution toward smaller grains (erosion) and can fragment large grains, creating a complex, irregular size distribution.

C. Specific Progenitor Behaviors

Low Mass ( $13-15 \, M_\odot$ ): Dust is almost completely destroyed ( $< 10^{-6} \, M_\odot$ surviving) in high-density environments.
High Mass ( $>60 \, M_\odot$ ): Despite fallback reducing total ejecta mass, the grains formed are large enough to survive the reverse shock better, making them efficient injectors of dust in dense ISM regions.

5. Significance and Implications

Early Universe Dust Enrichment: The results confirm that SNe can enrich the ISM with dust on very short timescales ( $\lesssim 30-40$ Myr), even after reverse shock destruction.
The 2175 Å UV Extinction Bump: The study predicts the release of carbonaceous grains ranging from $\sim 1$ nm to $\sim 100$ nm (up to $\sim 1 \, \mu$ m in non-rotating models). This supports the interpretation of the recently detected 2175 Å UV bump in galaxies at $z > 6$ (e.g., JADES-GS-z6-0) as being caused by small carbon nanoparticles or PAHs formed from the shattering of SN dust.
Chemical Evolution Models: The provided "effective dust yields" allow for more accurate modeling of dust-to-gas ratios in high-redshift galaxies, correcting previous models that may have overestimated yields by ignoring reverse shock destruction.
Limitations: The authors note that their models assume homogeneous ejecta and do not account for potential secondary dust formation in the cold dense shell between shocks (a process suggested by recent JWST observations), which could further increase effective yields.

Conclusion

The paper concludes that while the reverse shock is a major destructive force, massive rotating and non-rotating stars can still inject significant amounts of carbonaceous dust into the ISM. The survival of large grains ( $>10$ nm) ensures that SNe remain a viable mechanism for the rapid dust enrichment observed in the early universe, providing the necessary seeds for subsequent grain growth and the formation of the complex dust populations seen in high-redshift galaxies.