Typical Uncertainties Reached at BESSY II

For BESSY II typical uncertainties in the measurement of the parameters entering into the calculation of the spectral power Φ_E(E) are summarized in the table below.

		ΔΦ_E(E) /Φ_E(E) (*10^-3)
parameter / typical value		E=3 eV to 3 keV	E=3 keV to 10 keV	E=10 keV to 15 keV
electron beam current / 10.000(2) mA	I	0.20	0.20	0.20
electron energy / 1718.60(6) MeV	W	0.1	0.3	1.4
mag. induction / 1.30000(13) T	B	0.06	0.3	1.8
eff. vertical divergence / 3.5(7) μrad	Σ_y	0.06	0.2	0.4
distance to source point / 30000(2) mm	d	0.1	0.1	0.1
angle to orbit plane / 0.000(2) mrad	Ψ	0.04	0.2	0.3
total		0.3	0.6	2.3

N.B: the uncertainty reads as follows: 10.000(2) mA means 10 mA ± 0.002 mA (1 σ values)

Influence of the uncertainty in the parameters on the uncertainty of the calculated spectral radiant power
for different photon energies

Corresponding values for Metrology Light Source.

last update: 2011-09-30