A magnetically driven disc wind in the inner disc of PDS 70

TY - UNPB

T1 - A magnetically driven disc wind in the inner disc of PDS 70

AU - Campbell-White, Justyn

AU - Manara, Carlo F.

AU - Benisty, Myriam

AU - Natta, Antonella

AU - Claes, R. A.B.

AU - Frasca, Antonio

AU - Bae, Jaehan

AU - Facchini, Stefano

AU - Isella, Andrea

AU - Perez, Laura

AU - Pinilla, Paola

AU - Sicilia Aguilar, Aurora

AU - Teague, Richard

N1 - 13 pages, 7 figures, accepted for publication in The Astrophysical Journal

PY - 2023/8/18

Y1 - 2023/8/18

N2 - PDS 70 is so far the only young disc where multiple planets have been detected by direct imaging. The disc has a large cavity when seen at sub-mm and NIR wavelengths, which hosts two massive planets. This makes PDS 70 the ideal target to study the physical conditions in a strongly depleted inner disc shaped by two giant planets, and in particular to test whether disc winds can play a significant role in its evolution. Using X-Shooter and HARPS spectra, we detected for the first time the wind-tracing [O I] 6300AA line, and confirm the low-moderate value of mass-accretion rate in the literature. The [O I] line luminosity is high with respect to the accretion luminosity when compared to a large sample of discs with cavities in nearby star-forming regions. The FWHM and blue-shifted peak of the [O I] line suggest an emission in a region very close to the star, favouring a magnetically driven wind as the origin. We also detect wind emission and high variability in the He I 10830AA line, which is unusual for low-accretors. We discuss that, although the cavity of PDS 70 was clearly carved out by the giant planets, the substantial inner disc wind could also have had a significant contribution to clearing the inner-disc.

AB - PDS 70 is so far the only young disc where multiple planets have been detected by direct imaging. The disc has a large cavity when seen at sub-mm and NIR wavelengths, which hosts two massive planets. This makes PDS 70 the ideal target to study the physical conditions in a strongly depleted inner disc shaped by two giant planets, and in particular to test whether disc winds can play a significant role in its evolution. Using X-Shooter and HARPS spectra, we detected for the first time the wind-tracing [O I] 6300AA line, and confirm the low-moderate value of mass-accretion rate in the literature. The [O I] line luminosity is high with respect to the accretion luminosity when compared to a large sample of discs with cavities in nearby star-forming regions. The FWHM and blue-shifted peak of the [O I] line suggest an emission in a region very close to the star, favouring a magnetically driven wind as the origin. We also detect wind emission and high variability in the He I 10830AA line, which is unusual for low-accretors. We discuss that, although the cavity of PDS 70 was clearly carved out by the giant planets, the substantial inner disc wind could also have had a significant contribution to clearing the inner-disc.

U2 - 10.48550/arXiv.2308.09554

DO - 10.48550/arXiv.2308.09554

M3 - Preprint

BT - A magnetically driven disc wind in the inner disc of PDS 70

PB - arXiv

ER -