Using high angular resolution ($0B25-0B05) Very Large Array (VLA) observations made at 3.6 cm, 1.3 cm, and 7 mm during the period 1991-2004, we report the detection of large proper motions in the components of the radio continuum jet associated with the high-mass young stellar object (YSO) HW2 in the star-forming region Cepheus A. The relative proper motions observed for the two main components of the outflow, moving away from the central source in nearly opposite directions, are of the order of 140 mas yr À1 , or $480 km s À1 at a distance of 725 pc. The proper motions observed in the northeast and southwest lobes are not completely antiparallel, and the central elongated source seems to be changing orientation. We discuss possible scenarios to account for these and other observed characteristics. We also report the detection of a 7 mm compact continuum condensation of emission near the center of the thermal radio continuum jet, which we propose as the location of the exciting star.

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TIGRE is a new robotic spectroscopy telescope located in central Mexico at the La Luz Observatory of the University of Guanajuato. The 1.2 m telescope is fiber-coupled to anéchelle spectrograph with a spectral resolving power exceeding 20 000 over most of the covered spectral range between 3800Å and 8800Å, with a small gap of 130Å around 5800 A. TIGRE operates robotically, i.e. it (normally) carries out all observations without any human intervention, including, in particular, the target selection in any given observing night. In this paper we describe the properties of the TIGRE instrumentation and its technical realization, as well as our first operational experience with the performance and efficiency of the overall system. Finally, we present some examples of recent TIGRE observations.

We report results of radio continuum (1.3 and 3.6 cm) and H 2 O maser line observations, carried out with the Very Large Array ( VLA) in its A configuration, toward the star-forming region LkH 234. We detected five radio continuum sources ( VLA 1, VLA 2, VLA 3A, VLA 3B, and LkH 234) in a region of '5 00 ('5000 AU), of which three were previously unknown ( VLA 1, VLA 2, and VLA 3B). VLA 3A and VLA 3B seem to form a close ('220 AU ) binary system. Their elongated morphologies and positive spectral indices suggest that both VLA 3A and VLA 3B could be thermal radio jets. In addition, we detected three clusters of water masers, which are spatially associated with VLA 1, VLA 2, and VLA 3B. Based on the analysis of the distribution of the water masers and the characteristics of the continuum emission, we favor the new radio continuum source VLA 2 as the exciting source of the large-scale CO/[S ii] outflow observed in the region. Moreover, we find that the multiple outflows observed in the region share a similar orientation. Finally, our data confirm that there is no evidence indicating that the Herbig Be star LkH 234 is driving any of the outflows in the region.

We report sensitive, high angular resolution VLA 3.6 cm and 7 mm continuum observations toward the starforming region Cepheus A. Three embedded young stellar objects (YSOs) were found within a projected area of Ӎ ( A U 2 ). One of the sources is the already known radio continuum jet HW2 (detected at 0Љ .6 # 0Љ .6 400 # 400 3.6 cm and 7 mm), while the other two weak sources were not previously known. One of these two new sources is detected only at 7 mm and is located Ӎ0Љ .15 south from HW2. The other source, detected only at 3.6 cm, is located 0Љ .6 south from HW2 and nearly coincides with the center of the enigmatic expanding bubble of water masers recently detected with the Very Long Baseline Array. We suggest that this radio continuum source is the embedded YSO powering the water maser structure, but its nature is still unknown at present. We also discuss possible scenarios that could explain the surprisingly precise spherical geometry of the water maser bubble.