Kavli Affiliate: David Charbonneau
| First 5 Authors: Tim Cunningham, Pier-Emmanuel Tremblay, Mairi O’Brien, Evan B. Bauer, Mark A. Hollands
| Summary:
We present a population synthesis model which addresses the different mass
distributions of the metal-polluted and non-metal-polluted hydrogen-atmosphere
white dwarfs identified in volume-limited samples. Specifically,
metal-pollution has been observed to be rare in white dwarfs more massive than
$approx$0.7 $M_{odot}$. Our population synthesis model invokes episodic
accretion of planetary debris onto a synthetic population of white dwarfs. We
find that the observed difference can be explained in the regime where most
debris disks last for $10^4$$-$$10^6$ years. This is broadly consistent with
observational estimates that disk lifetimes are on the order 10$^5$$-$10$^7$
years. We also invoke an alternate model which explores an upper limit on
planetary system formation and survival around the intermediate-mass
progenitors of the more massive white dwarfs. In this scenario, we find an
upper limit on the polluted white dwarf mass of $M_{rm
wd}<0.72^{+0.07}_{-0.03}$ M$_{odot}$. This implies an empirical maximum
progenitor mass of $M_{rm ZAMS}^{rm max}=2.9^{+0.7}_{-0.3}$ M$_{odot}$. This
value is consistent with the maximum reliable host star mass of currently known
exoplanet systems. We conclude by imposing these two results on the sample of
He-atmosphere white dwarfs within 40,pc. We find that both scenarios are
capable of providing a consistent solution to the full sample of H- and
He-atmosphere white dwarfs.
| Search Query: ArXiv Query: search_query=au:”David Charbonneau”&id_list=&start=0&max_results=3