相关论文: Roman FFP Revolution: Two, Three, Many Plutos

Low-redshift strong-lensing galaxies can provide robust measurements of the stellar mass-to-light ratios in early-type galaxies (ETG), and hence constrain variations in the stellar initial mass function (IMF). At present, only a few such…

We provide new planetary nebula luminosity function (PNLF) distances to 19 nearby spiral galaxies that were observed with VLT/MUSE by the PHANGS collaboration. Emission line ratios are used to separate planetary nebulae (PNe) from other…

Microlensing is the only technique likely, within the next 5 years, to constrain the frequency of Jupiter-analogs. The PLANET collaboration has monitored nearly 100 microlensing events of which more than 20 have sensitivity to the…

The recent discovery of free-floating planets and their theoretical interpretation as celestial bodies, either condensed independently or ejected from parent stars in tight clusters, introduced an intriguing possibility. Namely, that some…

After finding more planets than expected at the shortest period, there has been an effort to explain their numbers by weak tidal friction. However, we find that the strength of tidal dissipation that would produce the occurence distribution…

We have found that Proxima Centauri, the star closest to our Sun, will pass close to a pair of faint background stars in the next few years. Using Hubble Space Telescope (HST) images obtained in 2012 October, we determine that the passage…

Giant planets are expected to form at orbital radii that are relatively large compared to transit and radial velocity detections (>1 AU). As a result, giant planet formation is best observed through direct imaging. By simulating the…

Massive gravitational microlensing programs were begun about a decade ago as a means to search for compact baryonic dark matter in the Galaxy, but before the first events were detected the technique was also proposed as a means of detecting…

Free-floating planets are recently drawing a special interest of the scientific community. Gravitational microlensing is up to now the exclusive method for the investigation of free-floating planets, including their spatial distribution…

A measurement by microlensing of the planetary mass function of planets with masses ranging from 5M_E to 10M_J and orbital radii from 0.5 to 10 AU was reported recently. A strategy for extending the mass range down to (1-3)M_E is proposed…

The Roman Space Telescope will be instrumental for characterizing the physical properties of galaxies and understanding their evolution across time. However, a complete view of galaxy star formation activity will only be possible with the…

Almost all the planets of our solar system have moons. Each planetary system has however unique characteristics. The Martian system has not one single big moon like the Earth, not tens of moons of various sizes like for the giant planets,…

We provide the first observational constraints on the sizes of the faintest galaxies lensed by the Hubble Frontier Fields (HFF) clusters. Ionizing radiation from faint galaxies likely drives cosmic reionization, and the HFF initiative…

We report the detection of several absorption lines of neutral phosphorus (P, Z=15) in archival near ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. We derive phosphorus…

We review the concept of the Fundamental Plane (FP), and present new results on the near-infrared FP. We show that the K-band FP differs both from the optical form and the virial expectation under the assumption of constant (M/L) and…

Using current technology, gravitational microlensing is the only method that can measure planet masses over the full parameter space of planet and stellar-host masses and at a broad range of planet-host separations. I present a…

We conducted a project of reinvestigating the 2017--2019 microlensing data collected by the high-cadence surveys with the aim of finding planets that were missed due to the deviations of planetary signals from the typical form of short-term…

Euclid and the Roman Space Telescope (Roman) will soon use grism spectroscopy to detect millions of galaxies via H$\alpha$ and [O III] $\lambda 5007$ emission. To better constrain the expected galaxy counts from these instruments, we use a…

We propose and evaluate the feasibility of a new strategy to search for planets via microlensing. This new strategy is designed to detect planets in "wide" orbits, i.e., with orbital separation, $a$ greater than $\sim 1.5 R_E$. Planets in…

We study the physical properties (size, stellar mass, luminosity, star formation rate) and scaling relations for a sample of 166 star-forming clumps with redshift $z \sim 2-6.2$. They are magnified by the Hubble Frontier Field galaxy…