===Monday 10th September===
Question 3:
* Group chose a 15O + α reaction with SECAR.\\
* Example_1.fox was edited to include a dipole which bends the trajectory 45°.\\
* (corresponding to ΔE/E) in coordinate SB was changed to 0.01 to create a small momentum spread:\\
{{screen_shot_2018-09-10_at_14.40.48.png|Trajectory of ray with small momentum difference }}
* PTY was changed to 3 to allow us to see the curvature: \\
{{group5_screen_shot_2018-09-10_at_15.03.08.png }}
Question 4:
* Used website to calculate θmax and ΔE/E
** Opening angle = 0.59 deg = 10 mrad which is less than the θmax=25 mrad so we're good. \\
** ΔE/E = (12.083-11.593)/(12.083+11.593) ~2% which is less than the 3.1% threshold so this also works.\\
{{:eandangle15oalpha.png?400|}}
Question 5:
* Proton capture on 15O one might expect from rp-process conditions is halted by the short half-life of 16F (40 keV) and its proton emission back to 15O. The two minute half-life of 15O further acts to limit transitions out of 15O, making 15O a waiting point in nucleosynthesis in this mass region. \\
* 15O + α reaction plays a role in bypassing this waiting point in the ignition of type I x-ray bursts on accreting neutron stars, but the cross-section at relevant temperatures/energies has been experimentally inaccessible to date. The next generation recoil separators, St. George at Notre Dame and SECAR at NSCL/FRIB may reach sensitivity to this important reaction. \\
Question 6:
* Using 'WRITE 6 VMAX(RAY(1))' xmax was calculated to be 0.2909704181068736E-002 m
* Plotting COSY beam size (x) and the quadrupole field strength(divided by aperture radius) and arrived at the graph below. Data doesn't appear to fit the quadratic form too closely.
* Calculated emittance is about 0.3 mm mrad, which is 50% larger than the 'real' emittance.
{{emittanceexample7.png}}
Question 7:
* Effective field length of Q2 was increased by 3% and the drift lengths either side were adjusted accordingly, so as not to change the the centre position of the quadrupole.
* The mass resolution was then optimised by minimising the function OBJ := 1/ABS(MRESOL_P1) by varying the strength of Q2, Q3 and Q4.
* This would increase the mass resolution to values of up to 85,000, however the emittance was very large.
{{Group5_screen_shot_2018-09-13_at_16.02.21.png }}
* We realised that we should alter our objective function, in order to re focus our beam. This was achieved with the function OBJ := 1/ABS(MRESOL_P1) + ABS(ME(1,2)), where we added on the (a|x) matrix element to also minimise.
{{Group5_screen_shot_2018-09-13_at_15.48.23.png }}
* This optimisation improved the mass resolution from 640.86349 to 724.66207, while still focusing.
Question 8:
* Tolerance for the beam size was found to be 0.00075 +/- 0.00004 m
* Tolerance for the beam position was found to be +/- 0.007 m