TY - JOUR
T1 - From Scattered-light to Millimeter Emission
T2 - A Comprehensive View of the Gigayear-old System of HD 202628 and its Eccentric Debris Ring
AU - Faramaz, Virginie
AU - Krist, John
AU - Stapelfeldt, Karl R.
AU - Bryden, Geoffrey
AU - Mamajek, Eric E.
AU - Matrà, Luca
AU - Booth, Mark
AU - Flaherty, Kevin
AU - Hales, Antonio S.
AU - Hughes, A. Meredith
AU - Bayo, Amelia
AU - Casassus, Simon
AU - Cuadra, Jorge
AU - Olofsson, Johan
AU - Su, Kate Y.L.
AU - Wilner, David J.
N1 - Publisher Copyright:
© 2019. The American Astronomical Society. All rights reserved..
PY - 2019
Y1 - 2019
N2 - We present here new observations of the eccentric debris ring surrounding the Gyr-old solar-type star HD 202628: at millimeter wavelengths with ALMA, at far-infrared wavelengths with Herschel, and in scattered light with the Hubble Space Telescope (HST). The ring inner edge is found to be consistent between ALMA and HST data. As radiation pressure affects small grains seen in scattered-light, the ring appears broader at optical than at millimeter wavelengths. The best fit to the ring seen with ALMA has inner and outer edges at 143.1 ± 1.7 au and 165.5 ± 1.4, respectively, and an inclination of 57.°4 ± 0.4 from face-on. The offset of the ring center of symmetry from the star allows us to quantify its eccentricity to be e= 0.09-0.01 +0.02. This eccentric feature is also detected in low resolution Herschel/PACS observations, under the form of a pericenter-glow. Combining the infrared and millimeter photometry, we retrieve a disk grain size distribution index of ∼-3.4, and therefore exclude in situ formation of the inferred belt-shaping perturber, for which we provide new dynamical constraints. Finally, ALMA images show four point-like sources that exceed 100 μJy, one of them being just interior to the ring. Although the presence of a background object cannot be excluded, we cannot exclude either that this source is circumplanetary material surrounding the belt-shaper, in which case degeneracies between its mass and orbital parameters could be lifted, allowing us to fully characterize such a distant planet in this mass and age regime for the very first time.
AB - We present here new observations of the eccentric debris ring surrounding the Gyr-old solar-type star HD 202628: at millimeter wavelengths with ALMA, at far-infrared wavelengths with Herschel, and in scattered light with the Hubble Space Telescope (HST). The ring inner edge is found to be consistent between ALMA and HST data. As radiation pressure affects small grains seen in scattered-light, the ring appears broader at optical than at millimeter wavelengths. The best fit to the ring seen with ALMA has inner and outer edges at 143.1 ± 1.7 au and 165.5 ± 1.4, respectively, and an inclination of 57.°4 ± 0.4 from face-on. The offset of the ring center of symmetry from the star allows us to quantify its eccentricity to be e= 0.09-0.01 +0.02. This eccentric feature is also detected in low resolution Herschel/PACS observations, under the form of a pericenter-glow. Combining the infrared and millimeter photometry, we retrieve a disk grain size distribution index of ∼-3.4, and therefore exclude in situ formation of the inferred belt-shaping perturber, for which we provide new dynamical constraints. Finally, ALMA images show four point-like sources that exceed 100 μJy, one of them being just interior to the ring. Although the presence of a background object cannot be excluded, we cannot exclude either that this source is circumplanetary material surrounding the belt-shaper, in which case degeneracies between its mass and orbital parameters could be lifted, allowing us to fully characterize such a distant planet in this mass and age regime for the very first time.
KW - circumstellar matter
KW - planetary systems
UR - http://www.scopus.com/inward/record.url?scp=85081238129&partnerID=8YFLogxK
U2 - 10.3847/1538-3881/ab3ec1
DO - 10.3847/1538-3881/ab3ec1
M3 - Article
AN - SCOPUS:85081238129
SN - 0004-6256
VL - 158
JO - Astronomical Journal
JF - Astronomical Journal
IS - 4
M1 - 162
ER -