Instrument's Characteristics

The reference for the instrument characteristics is the XSHOOTER User Manual.

Spectrograph characteristics

Arm λ-range N. of orders

scale

AB limit

  (nm)   (''/pix) (mag)
UVB 300-560 12 0.161 21.2 (at 356.1 nm, ord N.21)
21.7 (at 438.8 nm, ord N.17)
VIS 550-1020 15 0.158 20.9 (at 653.8 nm, ord N.35)
20.8 (at 777.6 nm, ord N.21)
NIR 1020-2480 16 0.248 21.0 (at 1245.2 nm, ord N.21)
20.6 (at 1634.4 nm, ord N.16)
18.7 (at 2179.2 nm, ord N.12)

 

Spectrograph resolution, for the NIR arm with the new slits wheel

arm slit width [1] R=(λ/Δλ) sampling arm slit width R=(λ/Δλ) sampling arm slit width R=(λ/Δλ) sampling
  (")   (pix/FWHM)   (")   (pix/FWHM)   (")   (pix/FWHM)
UVB 0.5 9700 3.1 VIS 0.4 18400 2.5 NIR 0.4 11600 1.6
  0.8 6700 5.0   0.7 11400 4.4   0.6 8100 2.5
                  0.6JH [2] 8100 2.5
  1.0 5400 6.2   0.9 8900 5.7   0.9 5600 3.7
                  0.9JH [2] 5600 3.6
  1.3 4100 8.1   1.2 6500 7.6   1.2 4300 4.8
  1.6 3200 9.9   1.5 5000 9.5        
UVB IFU [3] 8600 3.9 VIS IFU [3] 13500 3.7 NIR IFU [3] 8300 2.4

[1] All slits have a fixed length of 11''. [2] The 0.6"JH and 0.9"JH are the two new slits with the K-band blocking filter. [3] The IFU FoV is 4''x1.8 '' which is re-sampled in a 0.6'' x 12 '' slit in the spectrographs (not offerred anymore since P111).

 

Detector characteristics

arm detector readout mode gain RON readout time saturation
      (e-/ADU) (e-) (s) (ADU)
UVB 4k x 2k E2V CCD44-82 100,1x1,hg 0.63 2.4 68
65000
    100,1x2,hg 0.63 2.4 34  
    100,2x2,hg 0.63 2.4 17
 
    400,1x1,lg 1.83 4.6 16  
    400,1x2,lg 1.83 4.6 8
 
    400,1x2,lg 1.83 4.6 4
 
VIS 4k x 2k MIT/LL CCID 20 100,1x1,hg 0.64 3.4 89
65000
    100,1x2,hg 0.64 3.4 45  
    100,2x2,hg 0.64 3.4 23  
    400,1x1,lg 1.64 6.6 21  
    400,1x2,lg 1.64 6.6 11  
    400,2x2,lg 1.64 6. 6
 
NIR 2k x 2k Hawaii 2RG NDR 2.29 8-25[1] "1.46"
45000
AGCCD 562x528 fast 1.29 4.14 "1.2" 65535

[1] The RON depends on the DIT. For DIT > 300s, the RON is ~8 e-.

 

Old spectrograph resolution [1]

arm

slit width [2] R=(λ/Δλ) sampling arm slit width R=(λ/Δλ) sampling arm slit width R=(λ/Δλ) sampling
  ('')   (pix/FWHM)   (")   (pix/FWHM)   (")   (pix/FWHM)
UVB 0.5 9100 3.5 VIS 0.4 17400 3.0 NIR 0.4 11300 2.0
  0.8 6200 5.2   0.7 11000 4.8   0.6 8100 2.8
  1.0 5100 6.3   0.9 8800 6.0   0.9 5600 4.0
  1.3 4000 8.1   1.2 6700 7.9   1.2 4300 5.3
  1.6 3300 9.9   1.5 5400 9.7   1.5 3500 6.6
UVB IFU [3] 7900 4.1 VIS IFU [3] 12600 4.2 NIR IFU [3] 8100 2.8

[1] The values in this table have been measured for two slits in each arm and interpolated with a model for the others. [2] All slits have a fixed length of 11''. [3] The IFU FoV is 4''x1.8 '' which is re-sampled in a 0.6''x12 '' slit in the spectrographs.