TY - JOUR
T1 - Spectroscopy of TOI-1259B
T2 - an unpolluted white dwarf companion to an inflated warm Saturn
AU - Fitzmaurice, Evan
AU - Martin, David V.
AU - Martinez, Romy Rodriguez
AU - Vallely, Patrick
AU - Stephan, Alexander P.
AU - Boley, Kiersten M.
AU - Pogge, Rick
AU - El-Badry, Kareem
AU - Kunovac, Vedad
AU - Triaud, Amaury H. M. J.
N1 - 6 pages, accepted to MNRAS, minor revision of first arXiv version
PY - 2023/1
Y1 - 2023/1
N2 - TOI-1259 consists of a transiting exoplanet orbiting a main sequence star, with a bound outer white dwarf companion. Less than a dozen systems with this architecture are known. We conduct follow-up spectroscopy on the white dwarf TOI-1259B using the Large Binocular Telescope (LBT) to better characterise it. We observe only strong hydrogen lines, making TOI-1259B a DA white dwarf. We see no evidence of heavy element pollution, which would have been evidence of planetary material around the white dwarf. Such pollution is seen in ~ 25 - 50% of white dwarfs, but it is unknown if this rate is higher or lower in TOI-1259-like systems that contain a known planet. Our spectroscopy permits an improved white dwarf age measurement of 4.05 (+1.00 -0.42) Gyrs, which matches gyrochronology of the main sequence star. This is the first of an expanded sample of similar binaries that will allow us to calibrate these dating methods and provide a new perspective on planets in binaries.
AB - TOI-1259 consists of a transiting exoplanet orbiting a main sequence star, with a bound outer white dwarf companion. Less than a dozen systems with this architecture are known. We conduct follow-up spectroscopy on the white dwarf TOI-1259B using the Large Binocular Telescope (LBT) to better characterise it. We observe only strong hydrogen lines, making TOI-1259B a DA white dwarf. We see no evidence of heavy element pollution, which would have been evidence of planetary material around the white dwarf. Such pollution is seen in ~ 25 - 50% of white dwarfs, but it is unknown if this rate is higher or lower in TOI-1259-like systems that contain a known planet. Our spectroscopy permits an improved white dwarf age measurement of 4.05 (+1.00 -0.42) Gyrs, which matches gyrochronology of the main sequence star. This is the first of an expanded sample of similar binaries that will allow us to calibrate these dating methods and provide a new perspective on planets in binaries.
KW - astro-ph.EP
KW - astro-ph.SR
UR - http://mnras.oxfordjournals.org/
U2 - 10.1093/mnras/stac2879
DO - 10.1093/mnras/stac2879
M3 - Article
SN - 0035-8711
VL - 518
SP - 636
EP - 641
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 1
ER -