This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision Next revision Both sides next revision | ||
group_secar2.0 [2018/09/11 15:41] plastun |
group_secar2.0 [2018/09/12 12:01] wagner |
||
---|---|---|---|
Line 1: | Line 1: | ||
- | Group SECAR2.0 | + | ====== |
- | **DAY1 | + | -- by Alex, Nadeesha and Louis -- |
- | ** | + | |
- | Reaction: < | + | ===== DAY1===== |
+ | ==== Getting started ===== | ||
+ | |||
+ | Choosen example reaction: < | ||
+ | ⇒important for < | ||
Beam: < | Beam: < | ||
{{ : | {{ : | ||
- | Matrix:\\ | + | ====Understanding COSY Matrix |
+ | Command: OV 1 1 0 ; {order 1, phase space dim 1 INCLUDING ENERGY, # of parameters 0}\\ | ||
+ | Output:\\ | ||
|1.0|0.0|0.0|0.0|-0.41| | |1.0|0.0|0.0|0.0|-0.41| | ||
|2.2|1.0|0.0|0.0|-0.35|\\ | |2.2|1.0|0.0|0.0|-0.35|\\ | ||
+ | Explanation: | ||
+ | |R< | ||
+ | |R< | ||
R< | R< | ||
R< | R< | ||
Line 16: | Line 25: | ||
R< | R< | ||
+ | ==== Reaction Kinematics Calculation==== | ||
{{ : | {{ : | ||
- | Reaction summary for < | + | |
+ | Reaction summary for < | ||
The maximum γ energy is 8.481 MeV. The minimum γ energy is 7.249 MeV.\\ | The maximum γ energy is 8.481 MeV. The minimum γ energy is 7.249 MeV.\\ | ||
The maximum < | The maximum < | ||
- | Assume | + | If we assume a normalized emittance |
- | Geometric | + | With the spot size on the target, designed to be ±0.5 mm (1σ), the anglular spread |
- | Spot size on the target | + | Adding the calculated spread |
- | Adding the effect | + | ⇒COSY beam input: |
- | SB 0.0005 0.01726 0 0.0005 0.01726 0 0 0.0047 0 0 0 ;\\ | + | Output for this beam passing the dipole: |
{{ : | {{ : | ||
- | **DAY2** | + | ===== DAY2 ===== |
- | **Emittance | + | |
- | Distance | + | ==== Emittance |
+ | |||
+ | The distance | ||
{{ : | {{ : | ||
- | Q7 strenght | + | === Quadrupole |
- | |B [T] |Xmax[m] |ap [m] |Brho [Tm] |L [m] |K| | + | |
- | |0.02 |2.91E-03 |0.13 |0.8 |0.34 |0.065384615| | + | |B< |
- | |0.01 |2.27E-03 |0.13 |0.8 |0.34 |0.032692308| | + | |0.02 |2.91E-03 |0.13 |0.8 |6.085 |0.065384615| |
- | |0 |1.62E-03 |0.13 |0.8 |0.34 |0| | + | |0.01 |2.27E-03 |0.13 |0.8 |6.085 |0.032692308| |
- | |-0.01 |1.20E-03 |0.13 |0.8 |0.34 |-0.032692308| | + | |0 |1.62E-03 |0.13 |0.8 |6.085 |0| |
- | |-0.02 |9.08E-04 |0.13 |0.8 |0.34 |-0.065384615| | + | |-0.01 |1.20E-03 |0.13 |0.8 |6.085 |-0.032692308| |
- | |-0.03 |6.23E-04 |0.13 |0.8 |0.34 |-0.098076923| | + | |-0.02 |9.08E-04 |0.13 |0.8 |6.085 |-0.065384615| |
- | |-0.04 |9.54E-04 |0.13 |0.8 |0.34 |-0.130769231| | + | |-0.03 |6.23E-04 |0.13 |0.8 |6.085 |-0.098076923| |
- | |-0.05 |1.60E-03 |0.13 |0.8 |0.34 |-0.163461538| | + | |-0.04 |9.54E-04 |0.13 |0.8 |6.085 |-0.130769231| |
- | |-0.06 |2.26E-03 |0.13 |0.8 |0.34 |-0.196153846|\\ | + | |-0.05 |1.60E-03 |0.13 |0.8 |6.085 |-0.163461538| |
+ | |-0.06 |2.26E-03 |0.13 |0.8 |6.085 |-0.196153846|\\ | ||
+ | |||
+ | *Bρ the magnetic rigidity was extracted from COSY by comand CONS(CHIM)\\ | ||
+ | |||
+ | === Fit of the data to parabola === | ||
- | **Fit of the data to parabola** | ||
{{ : | {{ : | ||
+ | |||
+ | Fit result for parabola X< | ||
a = 0.000362572706 \\ | a = 0.000362572706 \\ | ||
b = 0.0834414129893 \\ | b = 0.0834414129893 \\ | ||
c = 3.506973286e-07\\ | c = 3.506973286e-07\\ | ||
- | double check for beam size calculation in Q7: X_calculated = X_cosy_read_out = 3.55\\ | ||
- | Emittance = 3.045387898578198e-07 | ||
- | 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.\\ | ||
+ | The consistency check for beam size calculation in Q7 shows:\\ | ||
+ | X_calculated = 3.13mm, X_cosy_read_out = 3.16mm at the Q7 exit.\\ | ||
+ | Emittance calculated from fit parameters ε= √(ac) / L< | ||
+ | Start beam emittance= XX · AX= 0.2 π mm mrad, so the emittance grows from the start to the focal point.\\ | ||
+ | This emittance grow is possibly due to the optics aberrations. That is because the input COSY file does a 4th-order-calculation. Also the measured points don't fit the parabola ideally, i.e. the optics is non-linear.\\ | ||
+ | |||
+ | ===== DAY3===== | ||
+ | ==== Impact of Lenght Change in Quadrupole 2 ==== | ||
+ | |||
+ | The effective length of Q2 was reduced by 3% to 0.291m with the drift lenghts before and after increased by 0.0045m.\\ | ||
+ | This led to a mass resolution change from 601 to 164 for the standard particle of the script. | ||