相关论文: CO bands in V4334 Sgr (Sakurai's Object): the 12C/…

We present an observation of the very late thermal pulse object V4334 Sgr (Sakurai's Object) with the Infrared Spectrometer (IRS) on the Spitzer Space Telescope. The emission from 5-38 microns is dominated by the still-cooling dust shell. A…

Theoretical spectral energy distributions are computed for a grid of hydrogen-deficient and carbon-rich model atmospheres with a range in T(eff) of 4000 - 5500 K and log g of 1.0 - 0.0, using the technique of opacity sampling, and taking…

We present UKIRT UIST spectra of Sakurai's Object (=V4334 Sgr) showing CO fundamental band absorption features around 4.7 microns. The line-centres are at heliocentric radial velocity of -170+/-30 km/s. The number and relative strengths of…

Theoretical spectral energy distributions computed for a grid of hydrogen-deficient and carbon-rich model atmospheres have been compared with the observed infrared (1--2.5 $\mu$m) spectra of V4334 Sgr (Sakurai's Object) on 1997 April 21 and…

We present a $0.8-2.5\,\mu$m spectrum of the Very Late Thermal Pulse object V4334 Sgr (Sakurai's Object), obtained in 2020 September. The spectrum displays a continuum that rises strongly to longer wavelengths, and is considerably brighter…

We present an analysis of a high resolution (R = 40000) infrared spectrum of the RS Oph secondary around the first overtone CO bands, obtained in 2008 May on the Gemini South 8 m. The 12CO and 13CO bands are well-resolved, and we compute…

We present observations of Sakurai's Object obtained at 1-5um between 2003 and 2007. By fitting a radiative transfer model to an echelle spectrum of CO fundamental absorption features around 4.7um, we determine the excitation conditions in…

Theoretical spectral energy distributions were computed for a grid of hydrogen-deficient and carbon-rich model atmospheres of T(eff) in the range of 5000-6250 K and log g = 1.0 - 0.0 by the technique of opacity sampling, taking into account…

We present an analysis of the evolution of circumstellar dust and molecules in the environment of the very late thermal pulse object V4334 Sgr (Sakurai's Object) over a $\sim20$-year period, drawing on ground-, airborne- and space-based…

V4334 Sgr (Sakurai's object) is an enigmatic evolved star that underwent a very late thermal pulse a few years before its discovery in 1996. It ejected a new, hydrogen-deficient nebula in the process. Emission lines from the newly ejected…

Absorption lines of the 12CO and 13CO molecular bands (Delta v = 2) at 2.29 -- 2.45 micron are modelled in spectrum of Arcturus (K2III). We compute a grid of model atmospheres and synthetic spectra for giant of Teff = 4300, log g = 1.5, and…

The high resolution optical spectra of H-deficient stars, R Coronae Borealis stars and H-deficient carbon stars are analyzed by synthesizing the C2 Swan bands (0,1), (0,0), and (1,0) using our detailed line-list and Uppsala model…

The (2,0) (3,0) and (4,0) bands of the A$^1\Pi-$X$^1\Sigma^+$ system of $^{12}$C$^{16}$O have been re-investigated by high-resolution vacuum ultraviolet absorption spectroscopy. A VUV Fourier-transform spectrometer, illuminated by…

V4334 Sgr (a.k.a. Sakurai's object) is the central star of an old planetary nebula that underwent a very late thermal pulse a few years before its discovery in 1996. We have been monitoring the evolution of the optical emission line…

In an echelle spectrum of X Per acquired with the Space Telescope Imaging Spectrograph we have identified individual rotational lines of 11 triplet-singlet (intersystem) absorption bands of ^12CO. Four bands provide first detections for…

We report the detection of fully resolved absorption lines of A-X bands from interstellar 12C17O and 12C18O, through high-resolution spectroscopy of X Per with the Space Telescope Imaging Spectrograph. The first ultraviolet measurement of…

CCD UBVRi photometry of the final helium flash object V4334 Sgr (Sakurai's Object), carried out during 1997 - 1999, is presented, and the light curve from its pre-discovery rise to the dust obscuration phase is constructed. The optical…

We have taken K-band spectroscopy of a sample of 13 pre-CVs in order to examine them for anomalous chemical abundances. In particular, we study the strength of the 12CO and 13CO absorption bands that have been found diminished and enhanced,…

We explore the infrared M band (4.7 um) spectrum of the class I protostar L1489 IRS in the Taurus Molecular Cloud. This is the highest resolution wide coverage spectrum at this wavelength of a low mass protostar observed to date (R=25,000;…

We present moderate-resolution ($R\sim4000$) $K$ band spectra of the planetary-mass companion VHS 1256 b. The data were taken with the OSIRIS integral field spectrograph at the W.M. Keck Observatory. The spectra reveal resolved molecular…