相关论文: CCD photometry of bright stars using objective wir…

In stellar interferometry, image quality improves significantly with the inclusion of more telescopes and the use of phase closure. We demonstrate, using first coherent and then partially coherent white light, a compact and efficient…

The epitaxial growth of two-dimensional (2D) $\beta-In_2Se_3$ material was obtained over 2-inches c-sapphire wafers using molecular beam epitaxy (MBE). Excellent quality of thick (90 nm) and very thin films, down to two quintuple layers (2…

A new analysis of CCD-based BVRI broad-band photometry for the globular cluster NGC2419 is presented, based on 340 CCD images either donated by colleagues or retrieved from public archives. The calibrated results have been made available…

Bright single and binary stars were observed at the 4.1-m telescope with a fast electron-multiplication camera in the regime of partial turbulence correction by the visible-light adaptive optics system. We compare the angular resolution…

We explore the limits of photometric reductions of crowded stellar fields observed with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope. Two photometric procedures, based on the DoPHOT and DAOPHOT/ALLFRAME programs…

We have summarized all Delta a measurements for galactic field stars (1474 objects) from the literature published over more than two decades. These measurements were, for the first time, compiled and homogeneously analyzed. The Delta a…

Context: Difference imaging has proven to be a powerful technique for detecting and monitoring the variability of unresolved stellar sources in M 31. Using this technique in surveys of galaxies outside the Local Group could have many…

The EPIC focal plane imaging spectrometers on XMM-Newton use CCDs to record the images and spectra of celestial X-ray sources focused by the three X-ray mirrors. There is one camera at the focus of each mirror; two of the cameras contain…

We demonstrate the feasibility of determining magnitudes of stars on archival photographic plates using a commercially available scanner. We describe one photometric approach that could serve as a useful example for other studies. In…

Several mission concepts are being studied to directly image planets around nearby stars. It is commonly thought that directly imaging a potentially habitable exoplanet around a Sun-like star requires space telescopes with apertures of at…

We have designed, constructed and put into operation a very large area CCD camera that covers the field of view of the 1.2 m Samuel Oschin Schmidt Telescope at the Palomar Observatory. The camera consists of 112 CCDs arranged in a mosaic of…

High precision astrometry aims at source position determination to a very small fraction of the diffraction image size, in high SNR regime. One of the key limitations to such goal is the optical response variation of the telescope over a…

We have begun a programme to obtain high-precision photometry of bright detached eclipsing binary (dEB) stars with the Wide field InfraRed Explorer (WIRE) satellite. Due to the small aperture of WIRE only stars brighter than V=6 can be…

In a few years the Kepler and TESS missions will provide ultra-precise photometry for thousands of RR Lyrae and hundreds of Cepheid stars. In the extended Kepler mission all targets are proposed in the Guest Observer (GO) Program, while the…

We discuss the system requirements for obtaining millimagnitude photometric precision over a wide field using small aperture short focal length telescope systems, such as are being developed by a number of research groups to search for…

Extremely metal-poor (EMP) stars ([Fe/H] < -3.0 dex) provide a unique window into understanding the first generation of stars and early chemical enrichment of the Universe. EMP stars are exceptionally rare, however, and the relatively small…

The first CCD photometric investigation of the open cluster NGC 7296 up to now was performed within the narrow band Delta a photometric system, which enables us to detect peculiar objects. A deeper investigation of that cluster followed,…

We conducted a search for occultations of bright stars by Kuiper Belt Objects (KBOs) to estimate the density of sub-km KBOs in the sky. We report here the first results of this occultation survey of the outer solar system conducted in June…

We observed the young open cluster NGC 2301 for 14 nights in Feb. 2004 using the orthogonal transfer CCD camera (OPTIC). We used PSF shaping techniques ("square stars") during the observations allowing a larger dynamic range (4.5…

Weak lensing provides an important route toward collecting samples of clusters of galaxies selected by mass. Subtle systematic errors in image reduction can compromise the power of this technique. We use the B-mode signal to quantify this…