J/A+A/633/A115 ALMA and NACO observations towards V1400 Cen (Kenworthy+, 2020)
ALMA and NACO observations towards the young exoring transit system
J1407 (V1400 Cen).
Kenworthy M.A., Klaassen P.D., Min M., van der Marel N., Bohn, A.
Kama M., Triaud A., Hales A., Monkiewicz J., Scott E., Mamajek E.E.
<Astron. Astrophys. 633, A115 (2020)>
=2020A&A...633A.115K 2020A&A...633A.115K (SIMBAD/NED BibCode)
ADC_Keywords: Infrared sources ; Millimetric/submm sources
Keywords: stars: pre-main sequence - submillimeter: planetary systems -
planets and satellites: formation - protoplanetary disks -
planet-disk interactions - planets and satellites: gaseous planets
Abstract:
Our aim was to directly detect the thermal emission of the putative
exoring system responsible for the complex deep transits
observed in the light curve for the young Sco-Cen star 1SWASP
J140747.93-394542.6 (V1400 Cen, hereafter J1407), confirming it as the
occulter seen in May 2007, and to determine its orbital parameters
with respect to the star.
We used the Atacama Large Millimeter/submillimeter Array (ALMA) to
observe the field centred on J1407 in the 340GHz (Band 7) continuum
in order to determine the flux and astrometric location of the ring
system relative to the star. We used the VLT/NACO camera to observe
the J1407 system in March 2019 and to search for the central planetary
mass object at thermal infrared wavelengths.
We detect no point source at the expected location of J1407, and
derive an upper limit 3σ level of 57.6uJy. There is a point
source detected at an angular separation consistent with the expected
location for a free-floating ring system that occulted J1407 in May
2007, with a flux of 89uJy consistent with optically thin dust
surrounding a massive substellar companion. At 3.8 microns with the
NACO camera, we detect the star J1407 but no other additional point
sources within 1.3 arcseconds of the star, with a lower bound on the
sensitivity of 6MJup at the location of the ALMA source, and down to
4MJup in the sky background limit.
The ALMA upper limit at the location of J1407 implies that a
hypothesised bound ring system is composed of dust smaller than 1 mm
in size, implying a young ring structure. The detected ALMA source has
multiple interpretations, including: (i) it is an unbound substellar
object surrounded by warm dust in Sco-Cen with an upper mass limit of
6MJup, or (ii) it is a background galaxy.
Description:
NAOS/CONICA observations with the VLT-UT1 at 3.8 microns on 2019-03-01
with a total integration of 5220 seconds and image reduced with ADI
and PCA. ALMA Band 7 observations towards J1407 (V1400 Cen) from
2017-07-20,22,24 with a total integration of 2 hours on source.
Objects:
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RA (2000) DE Designation(s)
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14 07 47.93 -39 45 42.8 J1407 = V1400 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 130 2 List of fits images
fits/* . 2 Individual fits images
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See also:
J/MNRAS/446/411 : V lightcurves of J1407 from PROMPT-4 and ROAD
(Kenworthy+, 2015)
Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 23 I4 --- Nx Number of pixels along X-axis
25- 28 I4 --- Ny Number of pixels along Y-axis
30- 52 A23 "datime" Obs.date Observation date
54- 60 F7.3 GHz Freq ? Observed frequency
62- 66 I5 Kibyte size Size of FITS file
68- 79 A12 --- FileName Name of FITS file, in subdirectory fits
81-130 A50 --- Title Title of the FITS file
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Acknowledgements:
Matthew Kenworthy, kenworthy(at)strw.leidenuniv.nl
(End) Matthew Kenworthy [Leiden Observatory], Patricia Vannier [CDS] 10-Jan-2020