REPORTS FROM Y.L. VARTANYAN AND COLLEAGUES ADVANCE KNOWLEDGE IN ASTROPHYSICS

Science Letter
November 3, 2009

"The stability of strange dwarfs for quark cores with M (0core) /M
(aEuro) = 10(-4), has been studied by calculating, in each individual
case, a series of strange dwarfs with configurations in which 5 a<…

10(-4), 10(-3), 5 a<… 10(-3), 10(-2), 1.31 a<… 10(-2), 1.6 a<…

10(-2), 1.7 a<… 10(-2), 2 a<… 10(-2), ranges from the values in
white dwarfs to rho (drip) = 4.3 a<… 10(11) g/cm(3), at which free
neutrons are produced in the crust. For the series with M (0core)
/M (aEuro) < 0.0131, stability is lost when rho (tr) < rho (drip),"
researchers in Yerevan, Armenia report (see also Astrophysics).

"For the series with M (0core) /M (aEuro) > 0.0131, the equality rho
(tr) = rho (drip) is reached before the strange dwarf attains its
maximum mass. Although the frequency of the radial pulsations in the
fundamental mode obeys omega (0) (2) > 0 for these configurations,
they are unstable with respect to transitions into a strange star
state with the same total number of baryons and a radius on the order
of that of neutron stars. An energy on the order of the energy in a
supernova explosion is released during these transitions," wrote Y.L.

Vartanyan and colleagues.

The researchers concluded: "It is shown that the gravitational red
shift of white and strange dwarfs are substantially different for
low and limiting (high) masses."

Vartanyan and colleagues published their study in Astrophysics
(Stability of strange dwarfs II. Computational results. Astrophysics,
2009;52(3):440-450).

For additional information, contact Y.L. Vartanyan, Erevan State
University, Yerevan, Armenia.

Publisher contact information for the journal Astrophysics is:
Springer, Plenum Publishers, 233 Spring St., New York, NY 10013, USA.