Capítulo 18. Urbanos
7. ANÁLISIS DE COMPROMISOS ( TRADE-OFFS ) Y SINERGIAS
MOT dynamics will change, causing a different steady-state and loading behavior of the MOT. A preliminary measurement can be seen in Fig. 7.3, where the trap was loaded to saturation with Ca+ ions, and caused an increased loading rate as well as a lower steady state for the Na MOT. A rate can be inferred from fits to the loading data, which will consist of the total scattering rate. We can infer the elastic scattering rate from this. This could be crucial in understanding the sympathetic cooling dynamics of the Na− Ca+ system when the Ca+ is excited into the D-state
discussed in Sec. 7.1.
7.4 D-state lifetime quenching measurement
There are many different types of molecular interactions between atoms and ions, including association to molecular ions. One such interaction is an inelastic collision, which does not conserve kinetic energy throughout the collision process. If one of the elements of a colliding system is excited, there is a possibility of collisional quenching (A∗ + B+ → A + B+ + hν). In the case of interest here, compare the measured
lifetime of the Ca+ ion in the D-state to the lifetime when in the presence of cold
neutral sodium. The quenching reaction might be of interest, since it will modify the lifetime of the long-lived D-state, and the mechanism may be different than what we have measured in the charge-exchange measurements. These are just some examples of interesting processes in the Na + Ca+ system
Appendices
Appendix A
PMT Mechanical Drawings
In this section I document prints for elements of the PMT holder. These elements were designed by our group and machined by the UConn Physics Department machine shop.
3.30 in 4.00 in 1.35 in DPTH 3.2 in 1.20 in 1.20 in DPTH .475 in 1.00 in THRU 1/4-20 THRD MAX DPTH .5 in 2.50 in 1.75 in
Name: Jonathan Kwolek Group: Win Smith Part: PMT Mount Material: Aluminum Date: 2016-08-08
145
1.00 in
0.125 in
Name: Jonathan Kwolek
Group: Win Smith
Part: PMT Mask Too
Material: Aluminum
Date: 2016-09-22
0.1575 in
1.00 in
0.2815 in
0.125 in
Name: Jonathan Kwolek
Group: Win Smith
Part: PMT Mask
Material: Aluminum
Date: 2016-09-22
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