J/A+A/635/A19 HD 117214 debris disk polarization images (Engler+, 2020)
HD 117214 debris disk: scattered-light images and constraints on the presence
of planets.
Engler N., Lazzoni C., Gratton R., Milli J., Schmid H.M., Chauvin G.,
Kral Q., Pawellek N., Thebault P., Boccaletti A., Bonnefoy M., Brown S.,
Buey T., Cantalloube F., Carle M., Cheetham A., Desidera S., Feldt M.,
Ginski C., Gisler D., Henning Th., Hunziker S., Lagrange A.M., Langlois M.,
Mesa D., Meyer M.R., Moeller-Nilsson O., Olofsson J., Petit C., Petrus S.,
Quanz S.P., Rickman E., Stadler E., Stolker T., Vigan A., Wildi F., Zurlo A.
<Astron. Astrophys. 635, A19 (2020)>
=2020A&A...635A..19E 2020A&A...635A..19E (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Polarization
Keywords: planetary systems - planet-disk interactions -
stars: individual object: HD 117214 -
stars: individual object: HIP 65875 -
techniques: high angular resolution - techniques: polarimetric
Abstract:
Young stars with debris disks are the most promising targets for an
exoplanet search because debris indicate a successful formation of
planetary bodies. Debris disks can be shaped by planets into ring
structures that give valuable indications on the presence and location
of planets in the disk.
We performed observations of the Sco-Cen F star HD 117214 to search
for planetary companions and to characterize the debris disk
structure.
HD 117214 was observed with the SPHERE subsystems IRDIS, IFS, and
ZIMPOL at optical and near-IR wavelengths using angular and
polarimetric differential imaging techniques. This provided the first
images of scattered light from the debris disk with the highest
spatial resolution of 25mas and an inner working angle <0.1". With
the observations with IRDIS and IFS we derived detection limits for
substellar companions. The geometrical parameters of the detected disk
were constrained by fitting 3D models for the scattering of an
optically thin dust disk. Investigating the possible origin of the
disk gap, we introduced putative planets therein and modeled the
planet-disk and planet-planet dynamical interactions. The obtained
planetary architectures were compared with the detection limit curves.
The debris disk has an axisymmetric ring structure with a radius of
0.42(±0.01)" or ∼45au and an inclination of 71(±2.5)° and
exhibits a 0.4" (∼40au) wide inner cavity. From the polarimetric
data, we derive a polarized flux contrast for the disk of
(Fpol)disk/F*=(3.1±1.2)x10-4 in the RI band.
The fractional scattered polarized flux of the disk is eight times
lower than the fractional IR flux excess. This ratio is similar to the
one obtained for the debris disk HIP 79977, indicating that dust
radiation properties are similar for these two disks. Inside the disk
cavity we achieve high-sensitivity limits on planetary companions with
a mass down to ∼4MJ at projected radial separations between 0.2" and
0.4". We can exclude stellar companions at a radial separation larger
than 75mas from the star.
Description:
The fits files contain the reduced SPHERE-ZIMPOL polarimetric
observations of HD 117214 in the Very Broad Band filter (lambda=735nm)
on 2018 February 28 and June 22 (selected frames). These are the
Stokes Qphi and Uphi images. Each image is 1024x1024 pixels with one
pixel corresponding to 3.6x3.6mas on sky, the north is up and the
east is to the left. The detector integration time of the images is
10-sec.
Objects:
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RA (2000) DE Designation(s)
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13 30 08.97 -58 29 04.4 HD 117214 = HIP 65875
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 64 2 List of fits files
fits/* . 2 Individual fits files
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right Ascension of center (J2000)
4- 5 I2 min RAm Right Ascension of center (J2000)
7- 11 F5.2 s RAs Right Ascension of center (J2000)
12 A1 --- DE- Declination sign of center (J2000)
13- 14 I2 deg DEd Declination of center (J2000)
16- 17 I2 arcmin DEm Declination of center (J2000)
19- 22 F4.1 arcsec DEs Declination of center (J2000)
24- 27 I4 --- Nx Number of pixels along X-axis
29- 32 I4 --- Ny Number of pixels along Y-axis
34- 37 I4 Kibyte size Size of FITS file
39- 46 A8 --- FileName Name of FITS file, in subdirectory fits
48- 64 A17 --- Title Title of the FITS file
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Acknowledgements:
Natalia Engler, englern(at)phys.ethz.ch
(End) N. Engler [ETH Zurich, Switzerland], P. Vannier [CDS] 22-Jan-2020