TEPCat: WASP-4


 

This page summarises the information held within TEPCat for the transiting planetary system WASP-4. Please see here for descriptions of the quantities given below.

 

Discovery and basic observable quantities:
 
Quantity Value Unit
Reference of discovery paper 2008ApJ...675L.113W  
Date of discovery paper 2007 / 11 / 22 y / m / d
Right ascension 23 34 15.06 h m s
Declination −42 03 41.1 d m s
V-band apparent magnitude 12.46 mag
K-band apparent magnitude 10.75 mag
Transit duration 0.08994
( 2.1586 )
day
hour
Transit depth 2.9 %
Time of mid-transit   2454966.782814 ± 0.000021     HJD or BJD
Orbital period 1.338231624 ± 0.000000068 days
Reference for orbital ephemeris   2015MNRAS.450.3101B  

 

Physical properties from the most recent detailed study:
 
Quantity Value Unit
Stellar effective temperature 5540 ± 55 K
Stellar metal abundance ([Fe/H] or [M/H])   −0.03 ± 0.09 dex
Stellar mass 0.927 ± 0.055   Msun
Stellar radius 0.910 ± 0.018 Rsun
Stellar logarithmic surface gravity 4.487 ± 0.010 c.g.s.
Stellar mean density 1.230 ± 0.022
( 1.736 ± 0.031 )
ρsun
g cm-3
Orbital eccentricity 0.0  
Orbital semimajor axis   0.02318 ± 0.00046  AU
Planetary mass 1.249 ± 0.052
( 397 ± 16 )
Mjup
Mearth
Planetary radius 1.364 ± 0.028
( 15.29 ± 0.31 )
Rjup
Rearth
Planetary surface gravity 16.64 ± 0.33
3.221 ± 0.009
m/s2
log(cgs)
Planetary mean density 0.460 ± 0.015
( 0.610 ± 0.020 )
ρjup
g cm-3
Planetary equilibrium temperature 1673 ± 17 K
Reference of detailed study 2012MNRAS.426.1291S  

 

Entries in the catalogue of Rossiter-McLaughlin measurements:
 
Reference λ (degrees)
Triaud et al. (2010)   4   + 34   - 43  
Sanchis-Ojeda et al. (2011)   −1   + 14   - 12  

 

 

WASP-4 has been examined as part of the Homogeneous Studies of Transiting Extrasolar Planets project. The details from this work have been given below. In most instances they are the same as the physical properties given above, but in some cases the Homogeneous Studies results given below have been superseded by newer analyses. Separate statistical and systematic errorbars are given where relevant.

Measured parameters Value Unit
Orbital velocity amplitude 242.1 ± 3.0 m/s
Stellar effective temperature 5540 ± 55 K
Stellar metal abundance ([Fe/H] or [M/H])   -0.03 ± 0.09 dex
Orbital inclination 89.0 ± 1.0   degrees
Fractional stellar radius (R* / a) 0.1825 +0.0011 −0.0010  
Fractional planetary radius (Rpl / a)   0.02812 +0.00022 −0.00014   
Light curve analysis reference 2009MNRAS.399..287S  
 
Derived parameters Value Unit
Stellar mass 0.927 ± 0.044 ± 0.034 Msun
Stellar radius 0.910 ± 0.015 ± 0.011 Rsun
Stellar logarithmic surface gravity 4.487 ± 0.009 ± 0.005 c.g.s.
Stellar mean density 1.230 ± 0.022 ρsun
Orbital semimajor axis   0.02318 ± 0.00037 ± 0.00028  AU
Planetary mass 1.249 ± 0.043 ± 0.030 Mjup
Planetary radius 1.364 ± 0.024 ± 0.016 Rjup
Planetary surface gravity 16.64 ± 0.33 m/s2
Planetary mean density 0.460 ± 0.014 ± 0.006 ρjup
Planetary equilibrium temperature 1673 ± 17 K
Safronov number 0.0458 ± 0.0010 ± 0.0005  
Main analysis reference 2012MNRAS.426.1291S  

 


Page generated on 2017/08/07           John Southworth   (Keele University, UK)