相关论文: Microlensing Optical Depth of the COBE Bulge

We calculate the optical depth and the number of events due to gravitational microlensing towards the Galactic bulge, the spiral arm directions $\gamma$ Scutum, $\beta$ Scutum, $\gamma$ Normae, $\vartheta$ Muscae and some dwarf galaxies in…

Red clump giant stars can be used as distance indicators to trace the mass distribution of the Galactic bar. We use RCG stars from 44 bulge fields from the OGLE-II microlensing collaboration database to constrain analytic tri-axial models…

We review recent gravitational microlensing results from the EROS, MACHO, and OGLE collaborations, and present some details of the very latest MACHO results toward the Galactic Bulge. The MACHO collaboration has now discovered in excess of…

The optical depth to microlensing toward M31 due to known stars in the disk of M31 itself is $\tau\sim 2\times 10^{-7}e^{-r/d}$ where $d$ is the disk scale length and $r$ is the distance along the major axis. Thus, there can be significant…

The distance to the Galactic center inferred from OGLE RR Lyrae variables observed in the direction of the bulge is Ro=8.1+-0.6 kpc. An accurate determination of Ro is hindered by countless effects that include an ambiguous extinction law,…

We used the red clump stars from the photometric data of the Optical Gravitational Lensing Experiment(OGLE II) survey and the Magellanic Cloud Photometric Survey (MCPS) for both the Clouds to estimate the depth.The observed dispersion in…

We present PLANET observations of OGLE-1999-BUL-23, a binary-lens microlensing event towards the Galactic bulge. PLANET observations in the I and V bands cover the event from just before the first caustic crossing until the end of the…

On the basis of the near infrared observations of bulge red clump stars near the Galactic center, we have determined the galactocentric distance to be R_0 = 7.52 +- 0.10 (stat) +- 0.35 (sys) kpc. We observed the red clump stars at |l| < 1.0…

The initial results of microlensing surveys toward the Galactic bulge and the LMC are puzzling. Toward the LMC, the total mass in MACHOs is of order half that required to explain the dark matter, but the estimated MACHO mass (~0.4 Msun) is…

We present a measurement of galaxy-galaxy lensing around a magnitude-limited ($i_{AB} < 22.5$) sample of galaxies from the Dark Energy Survey Science Verification (DES-SV) data. We split these lenses into three photometric-redshift bins…

The dependence of microlensing time scale frequency distributions and optical depth toward the galactic center on galactic model parameters is explored in detail for a distribution of stars consisting of the Zhao (1996) bar and nucleus and…

Observational study on near-infrared (IR) scattering properties of interstellar dust grains has been limited due to its faintness. Using all-sky maps obtained from Diffuse Infrared Background Experiment (DIRBE), we investigate the…

The DIRBE on the COBE spacecraft was designed primarily to conduct systematic search for an isotropic CIB in ten photometric bands from 1.25 to 240 microns. The results of that search are presented here. Conservative limits on the CIB are…

Foreground emission and scattered light from interplanetary dust (IPD) particles and emission from Galactic stellar sources are the greatest obstacles for determining the cosmic infrared background (CIB) from diffuse sky measurements in the…

The primary goal of this paper is to provide the evidence that can either prove or falsify the hypothesis that dark matter in the Galactic halo can clump into stellar-mass compact objects. If such objects existed, they would act as lenses…

The mass of the lenses giving rise to Galactic microlensing events can be constrained by measuring the relative lens-source proper motion and lens flux. The flux of the lens can be separated from that of the source, companions to the…

The Cosmic InfraRed Background (CIRB) is the sum total of the redshifted and reprocessed short wavelength radiation from the era of galaxy formation, and hence contains vital information about the history of galactic evolution. One of the…

We present the discovery of a Neptune-mass planet orbiting a 0.8 +- 0.3 M_Sun star in the Galactic bulge. The planet manifested itself during the microlensing event MOA 2011-BLG-028/OGLE-2011-BLG-0203 as a low-mass companion to the lens…

Measurements of the microlensing optical depth and event rate toward the Large Magellanic Cloud (LMC) can be used to probe the distribution and mass function of compact objects in the direction toward that galaxy - in the Milky Way disk,…

We model the split red clump of the Galactic bulge in OGLE-III photometry, and compare the results to predictions from two N-body models. Our analysis yields precise maps of the brightness of the two red clumps, the fraction of stars in the…