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We constrain the intrinsic architecture of Kepler planetary systems by modeling the observed multiplicities of the transiting planets (tranets) and their transit timing variations (TTVs). We robustly determine that the fraction of Sun-like stars with Kepler-like planets, $eta_{rm Kepler}$, is $30pm3%$. Here Kepler-like planets are planets that have radii $R_{rm p} gtrsim R_oplus$ and orbital periods $P<400$~days. Our result thus significantly revises previous claims that more than 50% of Sun-like stars have such planets. Combining with the average number of Kepler planets per star ($sim0.9$), we obtain that on average each planetary system has $3.0pm0.3$ planets within 400 days. We also find that the dispersion in orbital inclinations of planets within a given planetary system, $sigma_{i,k}$, is a steep function of its number of planets, $k$. This can be parameterized as $sigma_{i,k}propto k^alpha$ and we find that $-4<alpha<-2$ at 2-$sigma$ level. Such a distribution well describes the observed multiplicities of both tranets and TTVs with no excess of single tranets. Therefore we do not find evidence supporting the so-called Kepler dichotomy. Together with a previous study on orbital eccentricities, we now have a consistent picture: the fewer planets in a system, the hotter it is dynamically. We discuss briefly possible scenarios that lead to such a trend. Despite our Solar system not belonging to the Kepler club, it is interesting to notice that the Solar system also has three planets within 400 days and that the inclination dispersion is similar to Kepler systems of the same multiplicity.
We study the distribution of the photometric rotation period (Prot), which is a direct measurement of the surface rotation at active latitudes, for three subsamples of Sun-like stars: one from CoRoT data and two from Kepler data. We identify the main
Stellar members of binary systems are formed from the same material, therefore they should be chemically identical. However, recent high-precision studies have unveiled chemical differences between the two members of binary pairs composed by Sun-like
We present data obtained with the Infrared Array Camera (IRAC) aboard the Spitzer Space Telescope (Spitzer) for a sample of 74 young (t < 30 Myr old) Sun-like (0.7 < M(star)/M(Sun) < 1.5) stars. These are a sub-set of the observations that comprise t
We present an analysis of ~5 years of Lick Observatory radial velocity measurements targeting a uniform sample of 31 intermediate-mass subgiants (1.5 < M*/Msun < 2.0) with the goal of measuring the occurrence rate of Jovian planets around (evolved) A
Magnetic fields play an important role at all stages of stellar evolution. In Sun-like stars, they are generated in the outer convective layers. Studying the large-scale magnetic fields of these stars enlightens our understanding of the field propert