J/A+A/632/A25 PDS70 VLT/SPHERE images (Mesa+, 2019)
VLT/SPHERE exploration of the young multiplanetary system PDS70.
Mesa D., Keppler M., Cantalloube F., Rodet L., Charnay B., Gratton R.,
Langlois M., Boccaletti A., Bonnefoy M., Vigan A., Flasseur O., Bae J.,
Benisty M., Chauvin G., de Boer J., Desidera S., Henning T.,
Lagrange A.-M., Meyer M., Milli J., Mueller A., Pairet B., Zurlo A.,
Antoniucci S., Baudino J.-L., Brown Sevilla S., Cascone E., Cheetham A.,
Claudi R.U., Delorme P., D'Orazi V., Feldt M., Hagelberg J., Janson M.,
Kral Q., Lagadec E., Lazzoni C., Ligi R., Maire A.-L., Martinez P.,
Menard F., Meunier N., Perrot C., Petrus S., Pinte C., Rickman E.L.,
Rochat S., Rouan D., Samland M., Sauvage J.-F., Schmidt T., Udry S.,
Weber F.Wildi L.
<Astron. Astrophys. 632, A25 (2019)>
=2019A&A...632A..25M 2019A&A...632A..25M (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Spectroscopy
Keywords: instrumentation: spectrographs - methods: data analysis -
techniques: imaging spectroscopy - planetary systems -
stars: individual: PDS 70
Abstract:
PDS 70 is a young (5.4Myr), nearby (∼113pc) star hosting a known
transition disk with a large gap. Recent observations with SPHERE and
NACO in the near-infrared (NIR) allowed us to detect a planetary mass
companion, PDS70b, within the disk cavity. Moreover, observations in
Hα with MagAO and MUSE revealed emission associated to PDS 70 b
and to another new companion candidate, PDS70c, at a larger separation
from the star. PDS 70 is the only multiple planetary system at its
formation stage detected so far through direct imaging.
Our aim is to confirm the discovery of the second planet PDS 70 c
using SPHERE at VLT, to further characterize its physical properties,
and search for additional point sources in this young planetary
system. Methods. We re-analyzed archival SPHERE NIR observations and
obtained new data in Y, J, H and K spectral bands for a total of four
different epochs. The data were reduced using the data reduction and
handling pipeline and the SPHERE data center. We then applied custom
routines (e.g. ANDROMEDA and PACO) to subtract the starlight.
We re-detect both PDS 70 b and c and confirm that PDS70c is
gravitationally bound to the star. We estimate this second planet to
be less massive than 5MJup and with a Teff around 900K. Also, it has
a low gravity with log g between 3.0 and 3.5dex. In addition, a third
object has been identified at short separation (∼0.12") from the star
and gravitationally bound to the star. Its spectrum is however very
blue, so that we are probably seeing stellar light reflected by dust
and our analysis seems to demonstrate that it is a feature of the
inner disk. We, however, cannot completely exclude the possibility
that it is a planetary mass object enshrouded by a dust envelope. In
this latter case, its mass should be of the order of few tens of
M⊕. Moreover, we propose a possible structure for the
planetary system based on our data that, however, cannot be stable on
a long timescale.
Description:
For the present work we used both archival and new observations taken
with SPHERE (Beuzit et al., 2019A&A...631A.155B 2019A&A...631A.155B). The archival
observations were obtained on the nights of 2015-05-31 and 2018-02-24
and were previously used for the works presented in Keppler et al.
(2018A&A...617A..44K 2018A&A...617A..44K) and in Mueller et al. (2018A&A...617L...2M 2018A&A...617L...2M). In
addition to these data we also acquired new data on the nights of
2019-03-06 and 2019-04-13.
The first of these observations was carried out in the IRDIFS mode,
that is with IFS operating in Y and J spectral bands (between 0.95 and
1.35um) and IRDIS operating in the H band with the H23 filter pair
(wavelength H2=1.593um; wavelength H3=1.66 um)
The remaining observations were performed using the IRDIFS_EXT mode
that uses IFS in Y, J, and H spectral band (between 0.95 and 1.65um)
and IRDIS exploiting the K band with the K12 filter pair (K1=2.110um
and K2=2.251um).
Objects:
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RA (2000) DE Designation(s)
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14 08 10.15 -41 23 52.6 PDS 70 = V* V1032 Cen
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 147 8 List of fits files
fits/* . 8 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)
13 A1 --- DE- Declination sign of center (J2000)
14- 15 I2 deg DEd Declination of center (J2000)
17- 18 I2 arcmin DEm Declination of center (J2000)
20- 23 F4.1 arcsec DEs Declination of center (J2000)
25- 28 I4 --- Nx Number of pixels along X-axis
30- 33 I4 --- Ny Number of pixels along Y-axis
35- 44 A10 "date" Obs.date Observation date
46- 49 I4 Kibyte size Size of FITS file
51- 77 A27 --- FileName Name of FITS file, in subdirectory fits
79-147 A69 --- Title Title of the FITS file
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Acknowledgements:
Dino Mesa, dino.mesa(at)inaf.it
(End) Patricia Vannier [CDS] 24-Oct-2019