Foto: H. Balthasar
more at http://www.kis.uni-freiburg.de/kiswwwe2.html  (image added 2003-05-09)

The STELLA project is nearing its first milestone with the upcoming inauguration of its robotic building and the delivery of the first of two 1,2m telescopes. The first telescope, STELLA-I, will feed a high-resolution echelle spectrograph currently being build at the AIP and foreseen to be delivered to Tenerife together with the telescope by the end of the year. First light is foreseen for early 2003. The second telescope, STELLA-II, will be a photometric imaging telescope planned to go into operation in 2004. Please visit our Web site for further information and schedule updates.
Credits: K. G. Strassmeier, T. Granzer, M. Weber, M. Woche, A. Washüttl, S.-M. Bauer, J. Paschke, G. Hildebrandt (AIP), A. Hempelmann (Hamburg), J.H.M.M. Schmitt (Hamburg)
more at http://www.aip.de/stella/  (image added 2002-12-04)

The Potsdam Multi Aperture Spectrophotometer is an integral field instrument convering an 8"x8" field of view by a 16x16 element fibre lenslet array. The combination of 2 spatial and 1 spectral dimension in the same exposure offers an enormous potential to quantitatively analyse astronomical objects in complex surroundings with high photometric accuracy. The explicit knowledge of the point spread function allows the optimal separation of a point source from the background or even to separate contaminating sources.
credits: Th. Becker
more at http://www.aip.de/groups/opti/pmas/OptI_pmas.html  (image added 2002-12-10)

See above for introduction. - We have studied a couple of sample Planetary Nebulae in the bulge of the Andromeda galaxy (M31). Their quantitative spectroscopy is essentially limited by the contamination of diffuse gas emission and by the high background level of not resolved stellar objects. The image shows integral field exposures of PN27, PN29 and the contamination emission in H-alpha. We have applied the 2-channel image restoration algorithm to separate the PN from the background.
credits: Th. Becker
more at http://www.aip.de/groups/opti/pmas/OptI_pmas.html  (image added 2002-12-10)

Observing with PMAS at the 3.5m at Calar Alto from Aug. 28 to Sep. 6, 2002 we had an excellent opportunity to study for the second time a SN with an integral field spectrograph. The first one was discovered by the OASIS instrument.

We obtained spectra of the SN on several days during the run and have identified several absorption lines, which clearly confirm the supernova to be of Type Ia. The observations will allow tracing the change in velocity of the outflow. In addition to this we also obtained a spectrum of the bulge of the host galaxy. The reduced spectra of the SN were obtained with an interval of 48 hours. It is seen that the supernova is still getting brighter at the time of the last spectrum. The deep SiII absorption feature at 6150 Angstrom, which identifies the SN as a Type Ia event, is blueshifted from the rest frame of 6355 A. This corresponds to a blueshift of 12000 km/s, which is not unusual for a Type Ia SN.

An integral field spectrum of a SN is useful since it allows a very accurate estimate of the background flux and sky lines can be removed efficiently, so the physical conditions of the SN can be analysed. Specifically, the extinction by dust in the host galaxy can be measured.

For this reason, other groups have started to construct dedicated Integral Field Spectrographs just for the purpose to study supernovae, such as the SNIFS instrument. Utilising the standard candle nature of Type Ia SNe, the team behind the instrument will collect integral field spectroscopic data of nearby Type Ia SNe in order to calibrate the very distant SNe Type Ia. This will eventually lead to estimations of Omega_L and Omega_m with an accuracy of 5% and 2%, respectively, with data from the future SNAP satellite.

(credits: L. Christensen, T. Becker, K. Jahnke, A. Kelz, M. Roth, S.F. Sanchez, L. Wisotzki, AIP)
more at http://www.aip.de/groups/opti/pmas/OptI_pmas.html  (image added 2002-12-04)