TY - JOUR
T1 - The LEECH exoplanet imaging survey
T2 - Limits on planet occurrence rates under conservative assumptions
AU - Stone, Jordan M.
AU - Skemer, Andrew J.
AU - Hinz, Philip M.
AU - Bonavita, Mariangela
AU - Kratter, Kaitlin M.
AU - Maire, Anne Lise
AU - Defrere, Denis
AU - Bailey, Vanessa P.
AU - Spalding, Eckhart
AU - Leisenring, Jarron M.
AU - Desidera, S.
AU - Bonnefoy, M.
AU - Biller, Beth
AU - Woodward, Charles E.
AU - Henning, Th
AU - Skrutskie, Michael F.
AU - Eisner, J. A.
AU - Crepp, Justin R.
AU - Patience, Jennifer
AU - Weigelt, Gerd
AU - De Rosa, Robert J.
AU - Schlieder, Joshua
AU - Brandner, Wolfgang
AU - Apai, Dániel
AU - Su, Kate
AU - Ertel, Steve
AU - Ward-Duong, Kimberly
AU - Morzinski, Katie M.
AU - Schertl, Dieter
AU - Hofmann, Karl Heinz
AU - Close, Laird M.
AU - Brems, Stefan S.
AU - Fortney, Jonathan J.
AU - Oza, Apurva
AU - Buenzli, Esther
AU - Bass, Brandon
N1 - Publisher Copyright:
© 2018 Institute of Physics Publishing. All rights reserved.
PY - 2018
Y1 - 2018
N2 - We present the results of the largest L' (3.8 μm) direct imaging survey for exoplanets to date, the Large Binocular Telescope Interferometer Exozodi Exoplanet Common Hunt (LEECH). We observed 98 stars with spectral types from B to M. Cool planets emit a larger share of their flux in L' compared to shorter wavelengths, affording LEECH an advantage in detecting low-mass, old, and cold-start giant planets. We emphasize proximity over youth in our target selection, probing physical separations smaller than other direct imaging surveys. For FGK stars, LEECH outperforms many previous studies, placing tighter constraints on the hot-start planet occurrence frequency interior to ~20 au. For less luminous, cold-start planets, LEECH provides the best constraints on giant-planet frequency interior to ~20 au around FGK stars. Direct imaging survey results depend sensitively on both the choice of evolutionary model (e.g., hot- or coldstart) and assumptions (explicit or implicit) about the shape of the underlying planet distribution, in particular its radial extent. Artificially low limits on the planet occurrence frequency can be derived when the shape of the planet distribution is assumed to extend to very large separations, well beyond typical protoplanetary dust-disk radii (≤50 au), and when hot-start models are used exclusively. We place a conservative upper limit on the planet occurrence frequency using coldstart models and planetary population distributions that do not extend beyond typical protoplanetary dust-disk radii. We find that ≤90% of FGK systems can host a 7-10 MJupplanet from 5 to 50 au. This limit leaves open the possibility thatplanets in this range are common.
AB - We present the results of the largest L' (3.8 μm) direct imaging survey for exoplanets to date, the Large Binocular Telescope Interferometer Exozodi Exoplanet Common Hunt (LEECH). We observed 98 stars with spectral types from B to M. Cool planets emit a larger share of their flux in L' compared to shorter wavelengths, affording LEECH an advantage in detecting low-mass, old, and cold-start giant planets. We emphasize proximity over youth in our target selection, probing physical separations smaller than other direct imaging surveys. For FGK stars, LEECH outperforms many previous studies, placing tighter constraints on the hot-start planet occurrence frequency interior to ~20 au. For less luminous, cold-start planets, LEECH provides the best constraints on giant-planet frequency interior to ~20 au around FGK stars. Direct imaging survey results depend sensitively on both the choice of evolutionary model (e.g., hot- or coldstart) and assumptions (explicit or implicit) about the shape of the underlying planet distribution, in particular its radial extent. Artificially low limits on the planet occurrence frequency can be derived when the shape of the planet distribution is assumed to extend to very large separations, well beyond typical protoplanetary dust-disk radii (≤50 au), and when hot-start models are used exclusively. We place a conservative upper limit on the planet occurrence frequency using coldstart models and planetary population distributions that do not extend beyond typical protoplanetary dust-disk radii. We find that ≤90% of FGK systems can host a 7-10 MJupplanet from 5 to 50 au. This limit leaves open the possibility thatplanets in this range are common.
KW - Gaseous planets - stars
KW - High angular resolution
KW - Imaging - techniques
KW - Planetary systems - planets and satellites
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U2 - 10.3847/1538-3881/AAEC00
DO - 10.3847/1538-3881/AAEC00
M3 - Article
AN - SCOPUS:85090413863
VL - 156
JO - Astronomical Journal
JF - Astronomical Journal
SN - 0004-6256
IS - 6
M1 - aaec00
ER -