X-RAY WARM ABSORPTION AND EMISSION IN THE POLAR-SCATTERED SEYFERT 1 GALAXY Mrk 704

W e present a detailed study of the ionized environment of the Seyfert 1 galaxy Mrk 704 using medium-and high-resolution X-ray spectra obtained with a long XMM-Newton observation. The 0.3-10 keV continuum, well described by a power law (Gamma approximate to 1.86) and two blackbodies (kT approximate to 0.085 and 0.22 keV), is found to be affected by a neutral partial covering absorption (N-H approximate to 10(23) cm(-2), covering fraction approximate to 0.22) and two warm absorber components. We identify a low-ionization, xi similar to 20 erg cms(-1), and high outflow velocity, v similar to 1350 km s(-1), phase producing the OVI and Fe M-shell unresolved-transition array. An additional high-ionization warm absorbing phase with xi similar to 500 erg cm s(-1) and low outflow velocity, v similar to 540 km s(-1), gives rise to absorption features due to OVIII, OVIII, NVI, NVII, and C VI. We also detected weak emission lines of He-like triplets from OVII and NVI ions, thus making Mrk 704 a Seyfert 1 galaxy with both warm absorption and emission. The emission lines are well described by two warm emitting, photoionized media with different densities but comparable., suggesting discrete clouds of warm emission. The high-density phase (n(epsilon) similar to 10(13) cm(-3)) responsible for the resonance lines appears to outflow at high velocity similar to 5000 km s(-1). The low-velocity, low-density phase is likely similar to the X-ray line emitting regions found in Seyfert 2 galaxies. The physical conditions of warm emitters and warm absorbers suggest that these clouds are similar but observed in absorption along our line of sight and in emission at other lines of sight. The unique line of sight passing close to the torus opening angle is likely responsible for the neutral partial covering absorption and our view of emission lines due to the suppressed continuum in this polar-scattered Seyfert 1 galaxy.