  A dependence of the isobaric ratio Y(3H)/Y(3He) on the N/Z ratio of the
reconstructed quasiprojectile for the reaction of 28Si beam with 112,124Sn
targets at two different projectile energies 30 and 50 MeV/nucleon is
presented. We demonstrate a linear dependence of ln(Y(3H)/Y(3He)) on the
quasiprojectile N/Z ratio and show the dependence of the slope on reconstructed
excitation energy of the quasiprojectile. We relate this slope dependence at a
given excitation energy to the temperature of the fragmenting system. Using the
model assumptions of the statistical multifragmentation model, a method of
temperature determination is proposed. A caloric curve is constructed and
compared to the result of double isotope ratio method for the same set of data
and to the results of other studies.
