27 research outputs found
Watch This Space: Observing Merging White Dwarfs
The Laser Interferometer Space Antenna (LISA) will open the low-frequency
(0.1-100 mHz) part of the gravitational wave spectrum to direct observation. Of
order 3600 galactic close binary white dwarfs will be individually resolvable
in its all-sky spectrum, of which a dozen systems are expected to be on the
verge of merger, showing the effects of strong tidal heating and/or early onset
of tidal mass transfer. Optical study of these systems would provide important
insights into tidal dissipation mechanisms, and internal heating in merging
white dwarfs that sets ignition conditions for potential type Ia supernovae.
Theoretical modeling and instrumentation programs are needed now to enable a
campaign for optical identifications to exploit this opportunity.Comment: 6 pages. To be published in Binary-Star Evolution: Mass Loss,
Accretion and Mergers, ed. V. Kalogera and M. van der Sluys (AIP Conf. Ser.
The terrestrial gravitational wave environment from known sources
The objective of this project was to produce a gravitational wave spectral line list of all known binary stars producing expected strain amplitudes at Earth in excess of h = 10 (exp -21), or gravitational wave fluxes in excess of F = 10 (exp -12) erg cm(exp -2) s(exp -1). These strain and flux limits lie above the anticipated detection thresholds for space-borne laser interferometers capable of detecting gravitational radiation in the 10 micron Hz to 1 Hz frequency range. The source list was intended to provide frequency (including each harmonic), amplitude and phase (for each polarization and harmonic), and celestial coordinates for each system, lacking only the orientation of the principal polarization axis with respect to the pole of the coordinate system, and the sign of the source phase and frequency (or, equivalently, of the sense of rotation of the strain tensor with time) from providing a complete source description. Such a spectral line list would lay essential groundwork for high-sensitivity, low-frequency searches for gravitational radiation
A general catalogue of close binary systems
A comprehensive catalog of close binary stars to be used for the study of the fundamental properties of stars and for the exploration and elucidation of evolutionary processes in those systems, is presented. Spectroscopic binaries, variable stars, suspected variable stars, and interacting binaries are included in the scope of the catalog
A catalogue of potentially bright close binary gravitational wave sources
This is a current print-out of results of a survey, undertaken in the spring of 1985, to identify those known binary stars which might produce significant gravitational wave amplitudes at earth, either dimensionless strain amplitudes exceeding a threshold h = 10(exp -21), or energy fluxes exceeding F = 10(exp -12) erg cm(exp -2) s(exp -1). All real or putative binaries brighter than a certain limiting magnitude (calculated as a function of primary spectral type, orbital period, orbital eccentricity, and bandpass) are included. All double degenerate binaries and Wolf-Rayet binaries with known or suspected orbital periods have also been included. The catalog consists of two parts: a listing of objects in ascending order of Right Ascension (Equinox B1950), followed by an index, listing of objects by identification number according to all major stellar catalogs. The object listing is a print-out of the spreadsheets on which the catalog is currently maintained. It should be noted that the use of this spreadsheet program imposes some limitations on the display of entries. Text entries which exceed the cell size may appear in truncated form, or may run into adjacent columns. Greek characters are not available; they are represented here by the first two or three letters of their Roman names, the first letter appearing as a capital or lower-case letter according to whether the capital or lower-case Greek character is represented. Neither superscripts nor subscripts are available; they appear here in normal position and type-face. The index provides the Right Ascension and Declination of objects sorted by catalogue number
A Catalog and Atlas of Cataclysmic Variables: The Final Edition
The Catalog and Atlas of Cataclysmic Variables has been a staple of the CV
community for over 10 years. The catalog has grown from 751 CVs in 1993 to 1600
CVs at present. The catalog became a ``living'' edition in 2001, and its
contents have been continually updated since that time. Effective 27 January
2006, the catalog will transition to an archival site, with no further updates
to its contents. While it is antipicated that the site will remain active, we
present the complete contents of the site as a precaution against a loss of the
on-line data.Comment: 8 pages, including 6 table
A Catalog and Atlas of Cataclysmic Variables - The Living Edition
The Catalog and Atlas of Cataclysmic Variables (Edition 1 - 1993) and Edition
2 - 1997) has been a valuable source of information for the cataclysmic
variable (CV) community. However, the goal of having a central location for all
objects is slowly being lost as each new edition is generated. There can also
be a long time delay between new information becoming available on an object
and its publication in the catalog. To eliminate these concerns, as well as to
make the catalog more accessible, we have created a web site which will contain
a ``living'' edition of the catalog. We have also added orbital period
information, as well as finding charts for novae, to the catalog.Comment: LaTeX, 8 pages, 4 ps-figures, accepted by PAS