Stellar age is not disk age
Abstract
Disk fractions in star-forming clusters decline with stellar age, and are routinely read as the lifetime distribution of primordial protoplanetary disks. We argue that this reading is not warranted, because late infall can replenish or reform disks after collapse. To formalize this, we model the disk fraction as a superposition of primordial and environmentally replenished components, with region-to-region dispersion in the supply rate. Disk fractions cannot distinguish a long-lived disk from a short-lived one that is repeatedly replenished. In Sco--Cen both reproduce the data, the replenished model marginally better. Stellar age therefore need not equal disk age, and stars can host successive disk generations with distinct mass, orientation, and chemistry. A key test is whether regions of the same stellar age show a genuine spread in disk fractions, as environmental variation in the replenishment supply predicts.
Related
- 3D simulations of magnetospheric accretion in T Tauri stars I. Disk truncation, stellar torques, and application to observations
- Constraining AGN Disk Properties with Gravitational Waves from Inspiraling Stellar-Mass Binary Black Holes in Hierarchical Triple Systems
- Rapid Growth of Intermediate-Mass Black Holes through Disk-induced Stellar Disruptions
- Interaction of stellar dipole and disk magnetic fields in accretion-ejection systems
- Interaction of Stellar Dipole and Disk Magnetic Fields in Accretion–Ejection Systems
BibTeX
@misc{kuffmeier2026stellar,
title = {{Stellar age is not disk age}},
author = {M. Kuffmeier and A. Winter and A. Kuznetsova and M. Vioque and A. Gupta},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.17046},
eprint = {2609.17046},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.17046},
note = {CC BY-SA 4.0},
}
RIS
TY - UNPB
TI - Stellar age is not disk age
AU - M. Kuffmeier
AU - A. Winter
AU - A. Kuznetsova
AU - M. Vioque
AU - A. Gupta
PY - 2026
DA - 2026/09/15
PB - arXiv
DO - 10.48550/arxiv.2609.17046
UR - https://arxiv.org/abs/2609.17046
AB - Disk fractions in star-forming clusters decline with stellar age, and are routinely read as the lifetime distribution of primordial protoplanetary disks. We argue that this reading is not warranted, because late infall can replenish or reform disks after collapse. To formalize this, we model the disk fraction as a superposition of primordial and environmentally replenished components, with region-to-region dispersion in the supply rate. Disk fractions cannot distinguish a long-lived disk from a short-lived one that is repeatedly replenished. In Sco--Cen both reproduce the data, the replenished model marginally better. Stellar age therefore need not equal disk age, and stars can host successive disk generations with distinct mass, orientation, and chemistry. A key test is whether regions of the same stellar age show a genuine spread in disk fractions, as environmental variation in the replenishment supply predicts.
ER -