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An optical study (high resolution images and long-slit spectra in the Her range) of the Serpens reflection nebula (SRN) is presented. The SRN is a bipolar nebula illuminated by the low mass pre-main-sequence (PMS) star Serpens/SVS 2. The Ho profile of Serpens/SVS 2 is shown to be very broad (the width at a 10% of the peak intensity is 13.1 Angstrom (similar to 600 km/s)). The profile has three emission peaks centered at -137, 5 and 100 km/s. The relative strength of the peaks varies with the slit orientation. The blue and redshifted components have similar intensities at low inclinations (PA = -55 degrees and PA = -30 degrees) while at high inclinations the blueshifted component is weaker than the redshifted suggesting a significant contribution of absorption by low latitude outflowing gas. These profiles could be produced in a rotating, latitude dependent wind with the outflow axis parallel to the disk axis. The nebular H alpha profile is double peaked; it has a blue and a redshifted component at the same velocities as the star. The profile shows no significant variations along a given PA; the emission is best explained by single scattering of the stellar radiation. The absence of the 0-velocity emission component is suggestive of the presence of warm absorbing gas within a few stellar radii. There are several knots of gas and dust embedded within the north-western (NW) nebular lobe. These knots are connected by a faint emission, defining a helical path around the major axis of the nebula. This area is also characterized by an unusually large polarization that reaches a 30-40% at 0.95 mu m that is consistent with a concentration of large and reflecting dust grains that are presumably ice coated carbon grains. This region coincides with a ridge of hot (T similar or equal to 35 K) dust detected by IRAS along: the major axis of the SRN., Unidad Deptal. de Astronomía y Geodesia, Fac. de Ciencias Matemáticas, TRUE, pub

We present CCD images and long-slit spectra of the nebulous object GGD 33 and of the T Tauri star V 350 Cep in the star formation region NGC 7129. The data suggest that GGD 33a is a T Tauri star and likely the illuminating source of the whole GGD 33. Evidence of variability of GGD 33a is presented. Double-peaked [S II] emission lines are observed in GGD 33a. The high-velocity component of the [S II] emission could be related to a HH jet-like outflow observed very close to the star. V 350 Cep is embedded in a reflection nebulosity. High velocity mass outflow, detected through its blueshifted Halpha emission, seems to emanate from V 350 Cep. The spectrum of V 350 Cep presents a large number of permitted emission lines, but, except [S II], no forbidden emission lines have been identified in our spectra., Unidad Deptal. de Astronomía y Geodesia, Fac. de Ciencias Matemáticas, TRUE, pub

CCD images and spectra of high spectral resolution of GGD 34 are analyzed. The object is a jet consisting of three major condensations separated 0.08 pc one of each other and aligned over 0.17pc in the east-west direction. The three condensations emit strongly in [SII], [NII] and Halpha. The westernmost condensation has also significant continuum emission coming from what seems to be the bow-shaped borders of a cavity. A detailed study of the excitation conditions, densities and velocity field is presented. The excitation of the object is very low and the line ratios can be reproduced by mild radiative shocks at velocities less-than-or-equal-to 40 km s-1. The radial velocity of the gas is high, congruent-to 180 km s-1, indicating that the excitation is much lower than expected if the flow kinetic energy is fully spent into gas heating. This is generally observed in young stellar objects (YSO) jets. The exciting source of the outflow seems to be located at the western end of GGD 34, illuminating the cavity. The two easternmost condensations GGD 34/B and GGD 34/C are connected by a neatly shaped lobe emitting in [SII] and Halpha. The width of the lobe varies from 0.012pc in the condensations to 0.034 in the space in between. The lobe is not symmetric with respect to the jet axis but has a rather sinusoidal morphology. The velocity field in this region also can be well fitted by a sine curve. Morphology and velocity field are correlated; however they are not accompanied by significant changes in the excitation degree. We suggest that the properties of GGD 34 are produced by a ''kink'' plasma instability., Unidad Deptal. de Astronomía y Geodesia, Fac. de Ciencias Matemáticas, TRUE, pub