3 research outputs found
RZ Piscium Hosts a Compact and Highly Perturbed Debris Disk
RZ Piscium (RZ Psc) is well-known in the variable star field because of its
numerous, irregular optical dips in the past five decades, but the nature of
the system is heavily debated in the literature. We present multiyear infrared
monitoring data from Spitzer and WISE to track the activities of the inner
debris production, revealing stochastic infrared variability as short as weekly
timescales that is consistent with destroying a 90-km-size asteroid every year.
ALMA 1.3 mm data combined with spectral energy distribution modeling show that
the disk is compact (0.1--13 au radially) and lacks cold gas. The disk is
found to be highly inclined and has a significant vertical scale height. These
observations confirm that RZ Psc hosts a close to edge-on, highly perturbed
debris disk possibly due to migration of recently formed giant planets which
might be triggered by the low-mass companion RZ Psc B if the planets formed
well beyond the snowlines.Comment: 16 pages, 5 figures, accepted for publication in Ap
Millimeter Dust Emission and Planetary Dynamics in the HD 106906 System
Debris disks are dusty, optically thin structures around main sequence stars.
HD 106906AB is a short-period stellar binary, host to a wide separation planet,
HD 106906b, and a debris disk. Only a few known systems include a debris disk
and a directly imaged planet, and HD 106906 is the only one in which the planet
is exterior to the disk. The debris disk is edge-on and highly asymmetric in
scattered light. Here we resolve the disk structure at a resolution of 0.38"
(39 au) with the Atacama Large Millimeter/submillimeter Array (ALMA) at a
wavelength of 1.3 mm. We model the disk with both a narrow and broad ring of
material, and find that a radially broad, axisymmetric disk between radii of
50100 au is able to capture the structure of the observations without
evidence of any asymmetry or eccentricity, other than a tentative stellocentric
offset. We place stringent upper limits on both the gas and dust content of a
putative circumplanetary disk. We interpret the ALMA data in concert with
scattered light observations of the inner ring and astrometric constraints on
the planet's orbit, and find that the observations are consistent with a
large-separation, low-eccentricity orbit for the planet. A dynamical analysis
indicates that the central binary can efficiently stabilize planetesimal orbits
interior to 100 au, which relaxes the constraints on eccentricity and
semimajor axis somewhat. The observational constraints are consistent with in
situ formation via gravitational instability, but cannot rule out a scattering
event as the origin for HD 106906b's current orbit
RZ Piscium hosts a compact and highly perturbed debris disk
RZ Piscium (RZ Psc) is well-known in the variable star field because of its numerous, irregular optical dips in the past five decades, but the nature of the system is heavily debated in the literature. We present multiyear infrared monitoring data from Spitzer and WISE to track the activities of the inner debris production, revealing stochastic infrared variability as short as weekly timescales that is consistent with destroying a 90-km-size asteroid every year. ALMA 1.3 mm data combined with spectral energy distribution modeling show that the disk is compact ( ∼
0.1--13 au radially) and lacks cold gas. The disk is found to be highly inclined and has a significant vertical scale height. These observations confirm that RZ Psc hosts a close to edge-on, highly perturbed debris disk possibly due to migration of recently formed giant planets which might be triggered by the low-mass companion RZ Psc B if the planets formed well beyond the snowlines