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We present low-resolution spectropolarimetry for the symbiotic star Z Andromedae at four different epochs during the quiescent phase. The linear polarization of the continuum showed a temporal variation; the difference between the maximum and the minimum is 0.3%–0.6% in Stokes q and is larger with shorter wavelengths. Applying scattering models to this variation, we found the variation in the continuum may be correlated with the orbital motion of the binary and estimated the orbital inclination angle ic = 73 ◦ ± 14 ◦ and the orientation angle Ωc = 80 ◦ ± 5 ◦ . We also confirmed that the intrinsic linear polarization of the Raman line λ683 varies with the orbital phase; from this modulation, the orbital elements were derived as ir = 41 ◦ ± 8 ◦ and Ωr = 82 ◦ ± 2 ◦ . The inclination derived from the continuum has a large error, and the value is larger by twice the error than the inclination angle value derived from the Raman line. The derived orientation, in contrast, is comparable with that derived from the Raman line. The possible inconsistency in the inclination may be due to the simplicity of our adopted model, or it may be caused by a bias effect due to the low quality of the observed continuum polarization data. An accurate estimation of the inclination from the continuum polarization could settle the question, but that estimation requires more frequent observations that cover at least more than a few orbital cycles during the quiescent phase when the observations are not interrupted by the activity of the hot component.

We performed high-dispersion spectropolarimetry for the T Tauri star RY Tauri and measured linear polarization in seven forbidden lines of [OI]λλ5577, 6300, 6364, [NII]λ6583, [SII]λλ6716, 6731, and [FeII]λ7155. This is the first high-dispersion spectropolarimetry for forbidden lines in T Tauri stars. We successfully detected intrinsic polarization in the [OI]λ6300 line. The intrinsic [OI]λ6300 polarization corrected for the foreground polarization was derived as p[OI] = 1.17 ± 0.54% and θ[OI] = 107 ◦ ± 13 ◦ , whereas the polarization of the nearby continuum was pcont = 2.4−3.1% and θcont = 2 ◦ −11 ◦ . The position angle of [OI]λ6300 polarization is compared with the circumstellar structures found by previous studies. It is nearly perpendicular to the disk long-axis and parallel to the optical Hα jet. Both the perpendicularity and parallelism potentially suggest relatively axisymmetric distribution of the [OI]λ6300 emitting region and surrounding scattering medium. We constructed a simplified scattering model composed of a point source on a jet axis as an [OI]λ6300 emitter and a flat disk with an inner hole as a scatterer. Applying the observed polarization to the model suggests that the [OI]λ6300 emission emerges close to the central star with a possible separation of less than a few ×0.1 AU.

We present the results of our optical spectropolarimetry of nova V4444 Sagittarii 1999 in its early stage. The observations were performed on four nights from 1999 April 29 (t \ 2 days) to 1999 May 7 (t \ 10 days). The polarization properties, including the absence of polarization diUerence across strong emission lines, have remained unchanged through the period. The observed polarization degree increases monotonically toward shorter wavelength. We separate the interstellar polarization component from the observed polarization by assuming that the component intrinsic to this nova has a power-lawtype func- tion of wavelength. The decomposed intrinsic polarization can be explained by scattering due to small grains. These results suggest the preexistence of the dust cloud in the vicinity of the nova, at least several dozens of AU from the central star. Subject headings: circumstellar matternovae, cataclysmic variablespolarization ¨ stars: individual (V4444 Sagittarii)