Discovery of a directly imaged disk in scattered light around the Sco-Cen member Wray 15-788. (arXiv:1902.07723v1 [astro-ph.SR])
<a href="http://arxiv.org/find/astro-ph/1/au:+Bohn_A/0/1/0/all/0/1">A. J. Bohn</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kenworthy_M/0/1/0/all/0/1">M. A. Kenworthy</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ginski_C/0/1/0/all/0/1">C. Ginski</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Benisty_M/0/1/0/all/0/1">M. Benisty</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Boer_J/0/1/0/all/0/1">J. de Boer</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Keller_C/0/1/0/all/0/1">C. U. Keller</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Mamajek_E/0/1/0/all/0/1">E. E. Mamajek</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Meshkat_T/0/1/0/all/0/1">T. Meshkat</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Muro_Arena_G/0/1/0/all/0/1">G. A. Muro-Arena</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pecaut_M/0/1/0/all/0/1">M. J. Pecaut</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Snik_F/0/1/0/all/0/1">F. Snik</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wolff_S/0/1/0/all/0/1">S. G. Wolff</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Reggiani_M/0/1/0/all/0/1">M. Reggiani</a>
As part of our on-going survey we have carried out high-contrast imaging with As part of our on-going survey we have carried out high-contrast imaging with http://arxiv.org/icons/sfx.gif
VLT/SPHERE/IRDIS to obtain polarized and total intensity images of the young
($11^{+16}_{-7}$Myr old) K3IV star Wray 15-788 within the Lower Centaurus Crux
subgroup of Sco-Cen. For the total intensity images, we remove the stellar halo
by an approach based on reference star differential imaging in combination with
principal component analysis. Both total intensity and polarimetric data
resolve a disk around Wray 15-788. Modeling of the stellar spectral energy
distribution suggests that this is protoplanetary disk at a transition stage.
We detect a bright, outer ring at a projected separation of $sim$370mas
($approx$56au), hints for inner substructures at $sim$170mas ($approx$28au)
and a gap in between. Only within a position angle range of
$60^circ
VLT/SPHERE/IRDIS to obtain polarized and total intensity images of the young
($11^{+16}_{-7}$Myr old) K3IV star Wray 15-788 within the Lower Centaurus Crux
subgroup of Sco-Cen. For the total intensity images, we remove the stellar halo
by an approach based on reference star differential imaging in combination with
principal component analysis. Both total intensity and polarimetric data
resolve a disk around Wray 15-788. Modeling of the stellar spectral energy
distribution suggests that this is protoplanetary disk at a transition stage.
We detect a bright, outer ring at a projected separation of $sim$370mas
($approx$56au), hints for inner substructures at $sim$170mas ($approx$28au)
and a gap in between. Only within a position angle range of
$60^circ<varphi<240^circ$, we are confident at 5$sigma$ level to detect
actual scattered light flux from the outer ring of the disk; the remaining part
is indistinguishable from background noise. For the detected part of the outer
ring we determine a disk inclination of $i$=21$^circpm$6$^circ$ and a
position angle of $varphi$=76$^circpm$16$^circ$. Furthermore, we find that
Wray 15-788 is part of a binary system with the A2V star HD 98363 at a
separation of $sim$50” ($approx$6900au). The detection of only half of the
outer ring might be due to shadowing by a misaligned inner disk. A potential
substellar companion can cause the misalignment of the inner structures and can
be responsible for clearing the detected gap from scattering material. We can
not, however, rule out the possibility of a non-detection due to our limited
signal to noise ratio, combined with brightness azimuthal asymmetry. From our
data, we can exclude companions more massive than 10$M_mathrm{jup}$ within the
gap at a separation of $sim$230mas ($approx$35au).
