  Spectral energy distribution (SED) analyses, that include new millimeter (mm)
to far-infrared (FIR) observations, obtained with continuum instruments on the
Nobeyama and James Clerk Maxwell Telescopes and Infrared Space Observatory
(ISO), are presented for seven, nearby (< 45Mpc) FIR-bright elliptical
galaxies. These are analyzed together with archival FIR and short-wave radio
data obtained from the NASA/IPAC Extragalactic Database (NED). The radio to
infrared SEDs are best fit by power-law plus greybody models of dust residing
in the central galactic regions within 2.4kpc diameter and with temperatures
between about 21 and 28K, emissivity index approximately 2, and masses from
about 0.16 to 1.9 million solar masses. The emissivity index is consistent with
dust constituting amorphous silicate and carbonaceous grains previously modeled
for stellar-heated dust observed in the Galaxy and other nearby extragalactic
sources. Using updated dust absorption coefficients for this type of dust, dust
masses are estimated that are similar to those determined from earlier FIR data
alone, even though the latter results implied hotter dust temperatures. Fluxes
and masses that are consistent with the new FIR and submm data are estimated
for dust cooler than 20K within the central galactic regions. Tighter physical
constraints for such cold, diffuse dust (if it exists) with low surface
brightness, will need sensitive FIR-submm observations with the Spitzer Space
Telescope, SCUBA2, or ALMA.
