相关论文: The Central Star of NGC 2346 as a Clue to Binary E…

We report on advances in the study of the cores of NGC6302 and NGC6537 using infrared grating and echelle spectroscopy. In NGC6302, emission lines from species spanning a large range of ionization potential, and in particular [SiIX]3.934um,…

Among the distinguishing characteristics of the remarkable hot R Coronae Borealis star DY Cen, which was recently found to be a spectroscopic binary, is the presence of nebular forbidden lines in its optical spectrum. A compilation of…

Because of the similarity of the primary star of HS 1136+6646 to the planetary nebula central star BE Ursae Majoris, we did wide field imaging of the former with an H-alpha filter. No nebulosity was detected. On the other hand, the point…

EGB 6 is an ancient, low-surface-brightness planetary nebula. The central star, also cataloged as PG 0950+139, is a very hot DAOZ white dwarf (WD) with an apparent M dwarf companion, unresolved from the ground but detected initially through…

About 25% of all post-AGB stars are hydrogen-deficient, e.g. the PG1159 stars with a typical abundance pattern He:C:O = 33:50:17 (by mass). Only four of about 40 known PG1159 stars exhibit H in their spectra. The exciting star of the…

We present a combined analysis of rest-frame far-UV (1000-2000 A) and rest-frame optical (3600-7000 A) composite spectra formed from very deep observations of a sample of 30 star-forming galaxies with z=2.4+/-0.1, selected to be…

This paper is the fourth and final report on a project designed to study carbon abundances in a sample of planetary nebulae representing a broad range in progenitor mass and metallicity. We present newly acquired optical spectrophotometric…

The study presents a detailed spectroscopic analysis of the planetary nebulae (PNe) NGC~2392 and NGC~4361 using optical spectra obtained from the 2-m Himalayan Chandra Telescope (HCT) and mid-infrared spectra from archival \textit{Spitzer}…

We present an absolute parallax and relative proper motion for the central star of the planetary nebula NGC 6853 (The Dumbell). We obtain these with astrometric data from FGS 3, a white-light interferometer on {\it HST}. Spectral…

We have conducted a multi-wavelength study of the planetary nebula Abell 48 and give a revised classification of its nucleus as a hydrogen-deficient star of type [WN4]. The surrounding nebula has a morphology typical of PNe and importantly,…

This article discusses the physical and kinematical characteristics of planetary nebulae accompanying PG1159 central stars. The study is based on the parallax and proper motion measurements recently offered by Gaia space mission. Two…

We present a detailed investigation of SBS1150+599A, a close binary star hosted by the planetary nebula PN G135.9+55.9 (TS01, Stasinska et al, 2009). The nebula, located in the Galactic halo, is the most oxygen-poor one known to date and is…

We analyze the Far-UV/UV spectra of four central stars of planetary nebulae with strong wind features -- NGC 2371, Abell 78, IC 4776 and NGC 1535, and derive their photospheric and wind parameters by modeling high-resolution FUSE…

We report the discovery of an optical counterpart to a quiescent neutron star in the globular cluster Omega Centauri (NGC 5139). The star was found as part of our wide-field imaging study of Omega Cen using the Advanced Camera for Surveys…

At least one, but more likely two or more, eccentric neutron-star, carbon-oxygen white-dwarf binaries with an unrecycled pulsar have been observed. According to the standard scenario for evolving neutron stars which are recycled in common…

We have obtained high-spatial resolution ultraviolet and optical STIS spectroscopy and imaging of the metal-rich nuclear starburst in NGC3049. The stellar continuum and the absorption line spectrum in the ultraviolet are used to constrain…

The young planetary nebulae play an important role in stellar evolution when intermediate- to low-mass stars (0.8 $\sim$ 8 M$_\odot$) evolve from the proto-planetary nebulae phase to the planetary nebulae phase. Many young planetary nebulae…

This paper is the third in a series reporting on a study of carbon abundances in a carefully chosen sample of planetary nebulae representing a large range in progenitor mass and metallicity. We make use of the IUE Final Archive database…

We find the central stars of the planetary nebulae (PNe) HaTr 7 and ESO 330-9 to be close binary systems. Both have orbital periods of less than half a day and contain an irradiated cool companion to the hot central star. We provide light…

The increase in discovered close binary central stars of planetary nebulae is leading to a sufficiently large sample to begin to make broader conclusions about the effect of close binary stars on common envelope evolution and planetary…