Engineering topics

Szkody, Paula

Publications and source records attributed to Szkody, Paula.

39 records · Page 3

NASA NTRS1988

Cataclysmic variables

Recent observations of cataclysmic variables (CVs) at different wavelengths are reviewed, with a focus on their implications for theoretical models. Consideration is given to disk CVs (the flux distribution of the disk and changes during dwarf-nova outbursts), magnetic CVs (flux distributions and components), and the underlying stars. Typical data are presented in graphs, tables, and sample spectra, and it is concluded that more detailed multiwavelength observations are needed to improve models of radiative transfer and viscosity effects in accretion disks.

Szkody, Paula↗

NASA NTRS1987

Time-resolved IUE studies of cataclysmic variables. I - Eclipsing systems IP Peg, PG 1030+590, and V1315 Aql

IUE time-resolved spectra of the high-inclination cataclysmic variables IP Peg, PG 1030+590, and V1315 Aql are analyzed in order to determine the characteristics of the disk, hotspots, and white dwarfs. The UV continuum flux distributions are generally flatter than systems of low inclination and high mass-transfer rate, and the white dwarfs/inner disk appear to be relatively cool (15,000-19,000 K) for their orbital periods, possibly because the boundary layers are blocked from view. The continuum fluxes increase at spot phases, with the spot providing the dominant flux in IP Peg. The spot temperatures range from hot (20,000 K) in IP Peg, and perhaps in PG 1030+590, to cool (11,000 K) in V1315 Aql. The C IV emission lines show slightly larger decreases at spot phases than during eclipse, which implies an extended stream area.

Szkody, Paula↗

NASA NTRS1986

X-ray, UV, and optical observations of the dwarf nova BV Puppis

Exosat, IUE, optical spectroscopic, and broad-band photometric data on BV Pup are presented and analyzed in order to study the system characteristics and their relation to the high excitation of the emission lines. It is observed that: (1) at quiescence and outburst, the He II 4686 A/H-beta ratio for the star is larger than for other observed dwarf novae; (2) the X-ray flux is high for a system at outbursts and the X-ray flux correlates with an increased He II flux over the quiescent values; (3) the flat slope of the flux distribution at quiescence implies relatively low accretion rate; and (4) the abnormal UV line spectrum suggests a different geometry/opacity for the line emission zone compared to normal dwarf novae.

Szkody, Paula↗