Utilities


Utilities@GAPH

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  • AxVU100 Photodiode efficiency:
Nph/sec≈2.26 x 1013 I[μA]/hv[eV]
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Beamline: insertion device

source: Undulator; 36 periods L0=125 mm; B0max= 0.456 T; Kmax= 5.3; Ptotmax=0.95 kW
polarisation: linear
energy range: 13-900 eV
 Tab. 1 Source characteristics.

Gap can vary between 31 and 120 mm. It can be remotely set up by users (Gap < 100 mm) and there is the possibility to change GAP continuosly as function of photon wavelenght. Moreover, at the  high values of K parameter (low gap) the higher energy part of the spectrum is that of a wiggler.


Beamline: monochromator

The monochromator hosts 5 different gratings to attain the maximum resolving power in the entire energy range from 13 to 900 eV.  In the lower energy 1st order radiation from G1 and G6 can be used, depending on the experimental requirement for highest resolution (G1) or higher order rejection (indeed G6 has a MgF2 coating). G1 can be also used effectively in 2nd order in the 50-90 eV energy range.


grating energy range Max resolving power  flux(ph/sec/100mA)@selected energies
G#1 13-60  >25000  6.3·1010   @ 45 eV
G#1 2nd order 40-90  >28000 2.2·1011  @ 65 eV
 
G#3 80-180 >10000 1.5·1011  @ 86 eV
G#4 160-430 12200
>12000
1.5·1010  @ 245 eV
1.1·1010  @ 401 eV
G#5 360-900 10000 2.0·1010  @ 540eV
3·109  @ 680eV
G#6 13-25 10000 5·1011   @ 20 eV
Tab. 2 Energy ranges, max resolving power and photon flux at selected energies of the 5 available gratings of VASGM.



grating lines/mm radius[cm] energy range
G#1 400 1700 13-60 1st order
40-90 2nd order
G#3 1200 1700 80-180
G#4 1200 3200 160-430
G#5 1200 4600 360-900
G#6 140 1700 13-25
Tab. 3 Geometrical parameters of the 5 available spherical gratings of VASGM.

 

Ultima modifica il Venerdì, 23 Novembre 2018 07:40