Exoplanets and Stellar Physics

Abstract:

We consider several protostellar systems in which either a precessing jet or at least two misaligned jets have been observed. We assume that the precession of jets is caused by tidal interactions in noncoplanar binary systems. For Cep E, V1331 Cyg, and RNO 15-FIR, the inferred orbital separations and disk radii are in the range 4-160 AU and 1-80 AU, respectively, consistent with those expected for pre-main-sequence stars. Furthermore, we assume or use the fact that the source of misaligned outflows is a binary and evaluate the length scale over which the jets should precess as a result of tidal interactions. For T Tau, HH1 VLA 1/2, and HH 24 SVS63, it may be possible to detect a bending of the jets rather than "wiggling." In HH 111 IRS and L1551 IRS5, wiggling may be detected on the current observed scale. Our results are consistent with the existence of noncoplanar binary systems in which tidal interactions induce jets to precess.

Abstract:

The technique of integral field spectroscopy,: which provides simultaneous spectra for each pixel of a contiguous two-dimensional field of view, holds tremendous promise for improving our ability to study circumstellar environments. The technique becomes especially important at near infrared wavelengths, where rapid changes in the night sky background level limit the use of standard scanning techniques. In addition, combining the capabilities of adaptive optics systems with near infrared integral field spectrographs provides an unique way to enhance-spatial resolution for ground based observations. We present the technique of integral field spectroscopy, with special emphasis on the near infrared, and illustrate future developments by describing SINFONI, an adaptive optics assisted near infrared integral field spectrometer for the ESO VLT.

Abstract:

We propose to build a NIR imager/spectrograph for the LET which will support (1) seeing and diffraction limited direct imaging, (2) seeing and diffraction limited long-slit spectroscopy, (3) integral field spectroscopy and (4) tin small fields) OH-suppressed imaging of very faint objects. The instrument will cover the zJHK spectral bands with optimization for the K band. Therefore the optics will be cold (77 K). Whether the wavelength coverage can be extended to 5 mu without seriously compromising the K-band performance will be investigated during the design phase. At present a 2048 x 2048 HgCdTe array is foreseen as detector. Space will be reserved for the possibility of adding a (cold) multiple object spectroscopy unit. The feasibility of such a device will be investigated in parallel to the development of the main instrument. Six German institutes will cooperate to develop this LBT instrument.