Spectroscopy

A 40-arcsec wide long-slit was produced for us by the NBI, Copenhagen, Denmark, as part of a MOS-mask batch. The new slit was requested by Enric Palle (IAC) for accurate measurements of solar-system objects. In particular it was used to do spectrophotometry of the Earth-Sun transit as seen from two Jovian moons, both simultaneously sampled on the slit.

Through people at the TNG, we are currently exploring the possibility to enter a collaboration with the ``Osservatorio Astronomico di Brera'' in Milan, Italy, who are developing Volume-Phase Holographic (VPH) grisms for the ALFOSC clone AFOSC at the Asiago observatory in Italy. We have agreed on the design of a set of 3 high-efficiency grisms covering the ``blue'' (337-523 nm), ``green'' (443-687 nm), and ``red'' (576-1000 nm) part of the wavelength range covered by ALFOSC at a resolution of $\sim$1000. In combination with the new CCD (see above), this would make ALFOSC even more attractive to do low-resolution spectra, especially in the red, of transient sources such as GRBs and SNe. At this moment we do not have any specific cost estimate, but each grism is expected to cost a couple of 1000 Euro.

Thomas Augusteijn 2014-08-27