TY - JOUR

T1 - A search for starlight reflected from upsilon And's innermost planet

AU - Cameron, Andrew Collier

AU - Horne, Keith Douglas

AU - Penny, A

AU - Leigh, C

PY - 2002/2/11

Y1 - 2002/2/11

N2 - In data from three clear nights of echelle spectroscopy in 2000 October/November, and using improved Doppler tomographic signal-analysis techniques, we have carried out a deep search for starlight reflected from the innermost of v (upsilon) And's three planets. We place upper limits on the planet's radius R-P as functions of its projected orbital velocity K-P approximate to 139 sin i km s (1) for various assumptions about the wavelength-dependent geometric albedo spectrum p(lambda) of its atmosphere. For a grey albedo p we find Rprootp < 0.98 R-j, with 0.1 per cent false-alarm probability (4σ). For a Sudarsky, Burrows & Pinto Class V model atmosphere, the mean albedo in our 380-676 nm bandpass is [p] &SIM; 0.42, requiring R-P < 1.51 R-J, whereas an (isolated) Class IV model with [p] similar to 0.19 requires R-P < 2.23 R-J. The star's v(rot) sin i &SIM; 10 km s(-1) and estimated rotation period P-rot &SIM; 10 d suggest a high orbital inclination i &SIM; 70&DEG;-80&DEG;. We also develop methods for assessing the false-alarm probabilities of faint candidate detections, and for extracting information about the albedo spectrum and other planetary parameters from faint reflected-light signals.

AB - In data from three clear nights of echelle spectroscopy in 2000 October/November, and using improved Doppler tomographic signal-analysis techniques, we have carried out a deep search for starlight reflected from the innermost of v (upsilon) And's three planets. We place upper limits on the planet's radius R-P as functions of its projected orbital velocity K-P approximate to 139 sin i km s (1) for various assumptions about the wavelength-dependent geometric albedo spectrum p(lambda) of its atmosphere. For a grey albedo p we find Rprootp < 0.98 R-j, with 0.1 per cent false-alarm probability (4σ). For a Sudarsky, Burrows & Pinto Class V model atmosphere, the mean albedo in our 380-676 nm bandpass is [p] &SIM; 0.42, requiring R-P < 1.51 R-J, whereas an (isolated) Class IV model with [p] similar to 0.19 requires R-P < 2.23 R-J. The star's v(rot) sin i &SIM; 10 km s(-1) and estimated rotation period P-rot &SIM; 10 d suggest a high orbital inclination i &SIM; 70&DEG;-80&DEG;. We also develop methods for assessing the false-alarm probabilities of faint candidate detections, and for extracting information about the albedo spectrum and other planetary parameters from faint reflected-light signals.

KW - methods : data analysis

KW - techniques : spectroscopic

KW - stars : individual : upsilon And

KW - planetary systems

KW - EXTRASOLAR GIANT PLANETS

KW - TAU-BOOTIS

KW - STARS

KW - ANDROMEDAE

KW - COMPANIONS

KW - EXTRACTION

KW - SPECTRA

UR - http://www.scopus.com/inward/record.url?scp=0042259165&partnerID=8YFLogxK

UR - http://www.blackwell-synergy.com/doi/abs/10.1046/j.1365-8711.2002.05084.x

U2 - 10.1046/j.1365-8711.2002.05084.x

DO - 10.1046/j.1365-8711.2002.05084.x

M3 - Article

SN - 0035-8711

VL - 330

SP - 187

EP - 204

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

IS - 1

ER -