J/A+A/675/A205 SPHERE high-contrast data with PACO (Chomez+, 2023)
Preparation for an unsupervised massive analysis of SPHERE high-contrast data
with PACO. Optimization and benchmarking on 24 solar-type stars.
Chomez A., Lagrange A.-M., Delorme P., Langlois M., Chauvin G.,
Flasseur O., Dallant J., Philipot F., Bergeon S., Albert D., Meunier N.,
Rubini P.
<Astron. Astrophys. 675, A205 (2023)>
=2023A&A...675A.205C 2023A&A...675A.205C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Photometry ; Optical
Keywords: techniques: high angular resolution - techniques: image processing -
methods: data analysis - instrumentation: adaptive optic -
planets and satellites : detection
Abstract:
Despite tremendous progress in the detection and characterization of
extrasolar planetary systems in the last 25 years, we have not
pinpointed any Solar System analogues. In particular, Jupiter-like
planets (either mature or old) are barely detectable beyond 5 au with
indirect techniques and they are still out of the reach of direct
imaging techniques.Our study is aimed at a search for exoplanets
throughout the whole ESO/VLT-SPHERE archive with an improved and
unsupervised data analysis algorithm that could allow us to detect
massive giant planets at 5au. To prepare, test, and optimize our
approach, we gathered a sample of 24 solar-type stars observed with
SPHERE using angular and spectral differential imaging modes. We used
PACO, a recently developed new-generation algorithm that has been
shown to outperform classical methods. We also improved the SPHERE
pre-reduction pipeline and optimized the outputs of PACO to enhance
the detection performance. We developed custom-built spectral prior
libraries to optimize the detection capability of the ASDI mode for
both IRDIS and IFS. Compared to previous works conducted with more
classical algorithms, the contrast limits we derived with PACO are
more reliable and significantly improved, especially at short angular
separations, where a gain by a factor ten has been obtained between
0.2 and 0.5-arcsec. Under good observing conditions, planets down to
5Mjup, orbiting at 5au could be detected around stars within 60
parsec. We identified two exoplanet candidates that will require a
follow-up to test for a common proper motion.
Description:
We process, in a uniform manner, 37 dataset obtained via
SPHERE/VLT/ESO during the SHINE survey. We quantify the performance
increase thanks to this new pipeline and compare it to the one
obtained during the SHINE F150 survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 36 16 List of stars with contrast data in table 1
table1.dat 107 63 Properties of the signals detected in the
IRDIS images
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See also:
J/A+A/651/A71 : SHINE II (Langlois+, 2021)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Star name
14- 15 I2 h RAh Simbad right ascension (J2000)
17- 18 I2 min RAm Simbad right ascension (J2000)
20- 24 F5.2 s RAs Simbad right ascension (J2000)
26 A1 --- DE- Simbad declination sign (J2000)
27- 28 I2 deg DEd Simbad declination (J2000)
30- 31 I2 arcmin DEm Simbad declination (J2000)
33- 36 F4.1 arcsec DEs Simbad declination (J2000)
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Star name
13- 22 A10 "date" Obs.date Observing night
24- 27 F4.1 --- S/N Signal to noise ratio
29- 35 F7.2 mas Sep Separation
37- 41 F5.2 mas e_Sep Error on separation
43- 48 F6.2 deg PA Position angle
50- 53 F4.2 deg e_PA Error on position angle
55- 64 E10.2 --- contrastH2 Contrast relative to the star in the H2 band
66- 73 E8.2 --- e_contrastH2 Error on contrast relative to the star
in the H2 band
75- 84 E10.2 --- contrastH3 Contrast relative to the star in the H3 band
86- 93 E8.2 --- e_contrastH3 Error on contrast relative to the star
in the H3 band
95-107 A13 --- Status Final status of the detection (1)
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Note (1): final status as follows:
CC = candidate companion
BCKG = background source identified with proper motion
KC = known companion
SUSP BCKG CMD = background source based on color-magnitude diagram
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Acknowledgements:
Antoine Chomez, antoine.chomez(at)obspm.fr
References:
Desidera et al., Paper I 2021A&A...651A..70D 2021A&A...651A..70D, Cat. J/A+A/651/A70
Langlois et al., Paper II 2021A&A...651A..71L 2021A&A...651A..71L
(End) Patricia Vannier [CDS] 15-Jul-2023