Probability of Detecting a Planetary Companion during a Microlensing Event

  title={Probability of Detecting a Planetary Companion during a Microlensing Event},
  author={Stanton J. Peale},
  journal={The Astrophysical Journal},
  • S. Peale
  • Published 2001
  • Physics
  • The Astrophysical Journal
The averaged probability of detecting a planetary companion of a lensing star during a microlensing event toward the Galactic center when the planet to star mass ratio q = 0.001 is shown to have a maximum exceeding 10% at an orbit semimajor axis near 1.5 AU for a uniform distribution of impact parameters. This peak value is somewhat lower than the maximum of 17% obtained by Gould & Loeb in 1992, but it is raised to more than 20% for a distribution of source-lens impact parameters that is… Expand
Criteria in the Selection of Target Events for Planetary Microlensing Follow-up Observations
To provide criteria in the selection of target events preferable for planetary lensing follow-up observations, we investigate the variation of the probability of detecting planetary signals dependingExpand
Observation of the First Gravitational Microlensing Event in a Sparse Stellar Field: The Tago Event
We report the observation of the first gravitational microlensing event in a sparse stellar field, involving the brightest (V = 11.4 mag) and closest (~1 kpc) source star to date. This event wasExpand
Comparison of a Ground-based Microlensing Search for Planets with a Search from Space
We compare a space-based microlensing search for planets with a ground-based microlensing search originally proposed by D. Tytler. Perturbations of microlensing light curves when the lens star has aExpand
Astrometric Method for Breaking the Photometric Degeneracy between Binary-Source and Planetary Microlensing Perturbations
An extrasolar planet can be detected by microlensing because the planet can perturb the smooth lensing light curve created by the primary lens. However, it was shown by Gaudi that a subset ofExpand
Exoplanetary Microlensing
Gravitational microlensing occurs when a foreground star h appens to pass very close to our line of sight to a more distant background star. The foreground st ar acts as a lens, splitting the lightExpand
Properties of microlensing light curve anomalies induced by multiple planets
In this paper, we show that the pattern of microlensing light curve anomalies induced by multiple planets is well described by the superposition of those of the single-planet systems where theExpand
Microlensing Searches for Exoplanets
Gravitational microlensing finds planets through their gravitational influence on the light coming from a more distant background star. The presence of the planet is then inferred from the tell-taleExpand
Implications of Extrasolar Planets for Understanding Planet Formation
▪ Abstract The observed properties of extrasolar planets and planetary systems are reviewed, including discussion of the mass, period, and eccentricity distributions; the presence of multipleExpand
Worlds Beyond: A Strategy for the Detection and Characterization of Exoplanets
This report is a comprehensive study of the search for and study of planets around other stars (exoplanets). The young but maturing field of exoplanets is perhaps one of the most compelling fields ofExpand
An observational test for the anthropic origin of the cosmological constant
The existence of multiple regions of space beyond the observable Universe (within the so-called multiverse) where the vacuum energy density takes different values has been postulated as anExpand


Detection of Planetary Transits Across a Sun-like Star.
High-precision, high-cadence photometric measurements of the star HD 209458 are reported, which is known from radial velocity measurements to have a planetary-mass companion in a close orbit and the detailed shape of the transit curve due to both the limb darkening of thestar and the finite size of the planet is clearly evident. Expand
Abstract The statistical distribution of the masses of planets about stars between the Sun and the center of the Galaxy is constrained to within a factor of 3 by an intensive search for planetsExpand
Hundreds of gravitational microlensing events have now been detected toward the Galactic bulge, with many more to come. The detection of Ðne structure in these events has been theorized as anExpand
Limits on stellar and planetary companions in microlensing event OGLE-1998-BUL-14
We present the PLANET photometric data set for OGLE-1998-BUL-14, a high-magnification (A(max) similar to 16) event alerted by the OGLE collaboration toward the Galactic bulge in 1998. The PLANET dataExpand
On Microlensing Event Rates and Optical Depth toward the Galactic Center
The dependence of microlensing timescale frequency distributions and optical depth toward the Galactic center on Galactic model parameters is explored in detail for a distribution of stars consistingExpand
Detection efficiencies of microlensing data sets to stellar and planetary companions
Microlensing light curves are now being monitored with the temporal sampling and photometric precision required to detect small perturbations due to planetary companions of the primary lens.Expand
On Planetary Companions to the MACHO 98-BLG-35 Microlens Star
We present observations of the microlensing event MACHO 98-BLG-35, which reached a peak mag- ni—cation factor of almost 80. These observations by the Microlensing Planet Search (MPS) and MOAExpand
A Transiting "51 Peg-like" Planet.
Doppler measurements from Keck exhibit a sinusoidal periodicity in the velocities of the G0 dwarf HD 209458, having a semiamplitude of 81 m s-1 and a period of 3.5239 days, which is indicative of aExpand
The 1995 Pilot Campaign of PLANET: Searching for Microlensing Anomalies through Precise, Rapid, Round-the-Clock Monitoring
PLANET (the Probing Lensing Anomalies NETwork) is a worldwide collaboration of astronomers whose primary goal is to monitor microlensing events densely and precisely in order to detect and studyExpand
We show that Earth-mass planets orbiting stars in the Galactic disk and bulge can be detected by monitoring microlensed stars in the Galactic bulge. The star and its planet act as a binary lens whichExpand