• Publications
  • Influence
We present constraints on the stellar initial mass function (IMF) in two ultra-faint dwarf (UFD) galaxies, Hercules and Leo IV, based on deep Hubble Space Telescope Advanced Camera for SurveysExpand
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A Planet Orbiting the Star ρ Coronae Borealis
We report the discovery of near-sinusoidal radial velocity variations of the G0V star ρ CrB, with period 39.6 days and amplitude 67 m s-1. These variations are consistent with the existence of anExpand
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Halos of Spiral Galaxies. I. The Tip of the Red Giant Branch as a Distance Indicator
We have imaged the halo populations of a sample of nearby spiral galaxies using the Wide Field Planetary Camera 2 on board the Hubble Space Telescope with the aim of studying the stellar populationExpand
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The GIRAFFE Inner Bulge Survey (GIBS) - I. Survey description and a kinematical map of the Milky Way bulge
Context. The Galactic bulge is a massive, old component of the Milky Way. It is known to host a bar, and it has recently been demonstrated to have a pronounced boxy/peanut structure in its outerExpand
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Color-Luminosity Relations for the Resolved Hot Stellar Populations in the Centers of M31 and M32
We present Faint Object Camera (FOC) ultraviolet images of the central 14'' × 14'' of Messier 31 and Messier 32. The hot stellar populations detected in the composite UV spectra of these nearbyExpand
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The ELODIE survey for northern extra-solar planets - II. A Jovian planet on a long-period orbit around GJ 777 A
We present radial-velocity measurements obtained with the ELODIE and AFOE spectrographs for GJ 777 A (HD 190360), a metal-rich ((Fe/H)= 0.25) nearby (d= 15.9 pc) star in a stellar binary system. AExpand
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New insights on the Galactic Bulge Initial Mass Function
We have derived the Galactic bulge initial mass function of the SWEEPS field in the mass range 0.15 $< M/M_{\odot}<$ 1.0, using deep photometry collected with the Advanced Camera for Surveys on theExpand
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Halos of spiral galaxies. III. Metallicity distributions
We report results of a campaign to image the stellar populations in the halos of highly inclined spiral galaxies, with the fields roughly 10 kpc (projected) from the nuclei. We use the F814W (I) andExpand
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The Giraffe Inner Bulge Survey (GIBS) II. Metallicity distributions and alpha element abundances at fixed Galactic latitude
High resolution (R$\sim$22,500) spectra for 400 red clump giants, in four fields within $\rm -4.8^{\circ} \lesssim b \lesssim -3.4^{\circ}$ and $\rm -10^{\circ} \lesssim l \lesssim +10^{\circ}$, wereExpand
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Halos of Spiral Galaxies. II. Halo Metallicity-Luminosity Relation
Using the Hubble Space Telescope, we have resolved individual red giant branch stars in the halos of eight nearby spiral galaxies. The fields lie at projected distances between 2 and 13 kpc along theExpand
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