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 0.164 21.2 (at 356.1 nm, ord N.21)
21.7 (at 438.8 nm, ord N.17)
VIS 550-1020 15 0.154 20.9 (at 653.8 nm, ord N.35)
20.8 (at 777.6 nm, ord N.21)
NIR 1020-2480 16 0.245 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 2.9 VIS 0.4 18400 2.8 NIR 0.4 11600 8.4
  0.8 6700 4.2   0.7 11400 4.5   0.6 8100 12.0
                  0.6JH [4] 8100 12.0
  1.0 5400 5.2   0.9 8900 5.8   0.9 5600 17.4
                  0.9JH [3] 5600 17.4
  1.3 4100 6.9   1.2 6500 7.9   1.2 4300 22.6
  1.6 3200 8.9   1.5 5000 10.3        
UVB IFU [2] 8600 3.3 VIS IFU [3] 13500 3.8 NIR IFU [3] 8300 11.7

[1] All the slits have a fixed length of 11''. [2] The IFU FoV is 4''x1.8 '' which are re-sampled in a 0.6'' x 12 '' slit in the spectrographs. [3] The 0.6"JH and 0.9"JH are the two new slits with the K band blocking filter.

 

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 is RON~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 9100 3.5
  0.8 6200 5.2   0.7 11000 4.8   0.6 6200 5.2
  1.0 5100 6.3   0.9 8800 6.0   0.9 5100 6.3
  1.3 4000 8.1   1.2 6700 7.9   1.2 4000 8.1
  1.6 3300 9.9   1.5 5400 9.7   1.5 3300 9.9
UVB IFU [3] 7900 4.1 VIS IFU [3] 12600 4.2 NIR IFU [3] 8100 2.6

[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 the slits have a fixed length of 11''. [3] The IFU FoV is 4''x1.8 '' which are re-sampled in a 0.6''x12 '' slit in the spectrographs.