The following diagrams show how wavelengths map onto the NIRSPEC detector array when using the echelle with each of the standard blocking filters. In each diagram the blue strips are the orders transmitted by the blocking filter (with equal-power wavelengths of adjacent orders indicated on the left and right edges. The widths of the blue strips correspond to a 12 arcsecond long slit. The orange trapezoids match the size of the array. Note that the array covers the entire spectrum for the N1 blocking filter but does not do so for the longer wavelength filters, with the coverage decreasing at longer wavelengths. At longer wavelengths the array may be positioned (physically the echelle and grating are moved to do this) in order to select desired wavelength intervals, with multiple positions required to obtain complete spectra.

             0.947-1.120 µm

             1.089-1.293 µm 

             1.143-1.375 µm 

             1.241-1.593 µm

             1.431-1.808 µm 

             1.558-2.315 µm

             1.839-2.630 µm




Last update September 11, 2000; Tom Geballe