相关论文: The dwarf nova SS Cygni: what is wrong?
The mass of gas in protoplanetary discs is a quantity of great interest for assessing their planet formation potential. Disc gas masses are, however, traditionally inferred from measured dust masses by applying an assumed standard…
It is commonly accepted that jets have not been observed in CVs so far. This absence was recently explained by their low mass transfer rates compared with objects with jets. A mass accretion limit for jets in CVs was proposed to be about…
The detection of GW170817 and the identification of its host galaxy have allowed for the first standard-siren measurement of the Hubble constant, with an uncertainty of $\sim 14\%$. As more detections of binary neutron stars with redshift…
I derive the overall best distances for all 402 known galactic novae, and I collect their many properties. The centrepiece is the 74 novae with accurate parallaxes from the new Gaia data release. For the needed priors, I have collected 171…
The Gaia spacecraft has just released a large set of parallaxes, including 41 novae for which the fractional error is <30%. I have used these to evaluate the accuracy and bias of the many prior methods for getting nova-distances. The best…
Mass loss appears to be a common phenomenon among disk-accreting astrophysical systems. An outflow emanating from an accretion disk can act as a sink for mass, angular momentum and energy and can therefore alter the dissipation rates and…
We present a unified model for optical, ultraviolet (UV), and X-ray light curves of V1974 Cygni (Nova Cygni 1992). Based on an optically thick wind model of nova outbursts, we have calculated light curves and searched for the best fit model…
Recurring outbursts associated with matter flowing onto compact stellar remnants (black-holes, neutron stars, white dwarfs) in close binary systems, provide strong test beds for constraining the poorly understood accretion process. The…
It is unclear how directly imaged substellar companions with masses near the deuterium burning limit form, because these objects are rare and their bulk properties are not diagnostic of their formation. In this paper we revisit this problem…
The recurrent nova M31N 2008-12a experiences annual eruptions, contains a near-Chandrasekhar mass white dwarf, and has the largest mass accretion rate in any nova system. In this paper, we present Hubble Space Telescope (HST) WFC3/UVIS…
We present the first VLBI maps of H2O maser emission (lambda 1.3cm) in the nucleus of the Circinus Galaxy, constructed from data obtained with the Australia Telescope Long Baseline Array. The maser emission traces a warped, edge-on…
We present U, B and V light curves (taken from the literature) of the low mass X-ray binary Cygnus X-2. The ``lower envelope'' of the light curves folded on the orbital period are ellipsoidal. We fit an ellipsoidal model to the lower…
We discuss the multi-wavelength predictions of the two models proposed for SU UMa stars, i.e the enhanced mass transfer (EMT) and the tidal thermal instability (TTI) models. We focus on the systematic differences of the suggested scenarios…
This study presents all available, multi-epoch 3.6 and 4.5 $\mu$m photometry from Spitzer Space Telescope observations of white dwarf debris disks, including weekly cadence observations of 16 relatively bright systems, and 5 h staring-mode…
We update the method of the Holmberg & Flynn (2000) study, including an updated model of the Milky Way's interstellar gas, radial velocities, an updated reddening map, and a careful statistical analysis, to bound the allowed surface density…
CW Mon is a relatively bright and nearby SS Cyg-type dwarf nova frequently used in detailed analysis of cataclysmic variables and statistical studies. Using Transiting Exoplanet Survey Satellite (TESS) observations, we found that the…
We present Surface Brightness Fluctuation distances of nine early-type dwarf galaxies and the S0 galaxy NGC 4150 in the Local Volume based on deep B- and R-band CCD images obtained with the 2.56 metre Nordic Optical Telescope. Typically,…
We use the microlensing variability observed for eleven gravitationally lensed quasars to show that the accretion disk size at a rest-frame wavelength of 2500 Angstroms is related to the black hole mass by log(R_{2500}/cm)=(15.78\pm0.12) +…
Using a cross-correlation method, we study the X-ray halo of Cyg X-3. Two components of dust distributions are needed to explain the time lags derived by the cross-correlation method. Assuming the distance as 1.7 kpc for Cygnus OB2…
The recurrent nova T Pyxidis has erupted six times since 1890, with its last outburst in 2011, and the relatively short recurrence time between classical nova explosions indicates that T Pyx must have a massive white dwarf accreting at a…