This is an old revision of the document!
Group SECAR2.0
DAY1
Reaction: 45V(p,γ)46Cr
Beam: 45V13+ of 135 MeV (1% enegry spread)
Matrix:
1.0 | 0.0 | 0.0 | 0.0 | -0.41 |
2.2 | 1.0 | 0.0 | 0.0 | -0.35 |
R11 = 1.0 is “Magnification”, i.e. no magnification provided with the dipole.
R12 = 0.0 is “Focusing”, i.e. no focusing is provided by the dipole.
R21 = 2.2 is approximate “Path length”,which is 0.5+0.78+1.0 meters
R22 = 0.0 mean that output angles does not depend on input angles.
R15 = -0.41 is ToF difference due to different initial position.
R25 = -0.35 is ToF difference due to different initial angle.
Reaction summary for 45V+p→γ+46Cr, Ek(45V)=135 MeV
The maximum γ energy is 8.481 MeV. The minimum γ energy is 7.249 MeV.
The maximum 46Cr energy is 132.634 MeV. The minimum 46Cr energy is 131.402 MeV. The maximum 46Cr angle is 0.13 degrees.
Assume normalized emittance 0.6 π mm mrad provided from ReA3 at 3.0 MeV/u.
Geometric emittance is 0.6/0.08 = 7.5 π mm mrad.
Spot size on the target is ±0.5 mm (full width). Then anglular spread is ±15 mrad.
Adding the effect from the target of 0.13 deg = ±2.26 mrad we get ±17.26 mrad of angular spread:
SB 0.0005 0.01726 0 0.0005 0.01726 0 0 0.0047 0 0 0 ;
DAY2
Emittance measurement
Distance between Q7 center and focal plane is 6.085 m.
Q7 strenght variation:
B [T] | Xmax[m] | ap [m] | Brho [Tm] | L [m] | K |
0.02 | 2.91E-03 | 0.13 | 0.8 | 0.34 | 0.065384615 |
0.01 | 2.27E-03 | 0.13 | 0.8 | 0.34 | 0.032692308 |
0 | 1.62E-03 | 0.13 | 0.8 | 0.34 | 0 |
-0.01 | 1.20E-03 | 0.13 | 0.8 | 0.34 | -0.032692308 |
-0.02 | 9.08E-04 | 0.13 | 0.8 | 0.34 | -0.065384615 |
-0.03 | 6.23E-04 | 0.13 | 0.8 | 0.34 | -0.098076923 |
-0.04 | 9.54E-04 | 0.13 | 0.8 | 0.34 | -0.130769231 |
-0.05 | 1.60E-03 | 0.13 | 0.8 | 0.34 | -0.163461538 |
-0.06 | 2.26E-03 | 0.13 | 0.8 | 0.34 | -0.196153846 |
a = 0.000362572706
b = 0.0834414129893
c = 3.506973286e-07
double check for beam size calculation in Q7: X_calculated = X_cosy_read_out = 3.55
Emittance = 3.045387898578198e-07 π m rad= 0.3 π mm mrad
start beam emittance= XX * AX= 0.2 π mm mrad so the emittance grows from the start to the focal point
Emittance grows due to the optics aberrations. Input COSY file shows 4th-order-calculation. Also measured points don't fit the parabola ideally, i.e. optics is non-linear.