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--- tripleg_group [2018/09/14 00:37]
gastis
+++ tripleg_group [2018/09/14 09:32] (current)
gao
@@ Line 1: / Line 1: @@
-This is the tutorial written by the 'triple G' group! We chose to study the 15O+4He radiative capture reaction using SECAR.
+This is the tutorial written by the 'triple G' group!
 In this tutorial, we will explain step by step how we work on the project [[https://wikihost.nscl.msu.edu/JIOSS/lib/exe/fetch.php?media=project_for_the_jina_ion_optics_for_recoil_separator_school_v4.pdf|here]]
 **Q3.**
 We use the example from the wiki [[https://wikihost.nscl.msu.edu/JIOSS/lib/exe/fetch.php?media=dispersion.zip|Dispersion]] as a starting point and do the following:
 , Find the lines as shown in the picture below:
 {{:dispersion_ele.png?direct&400|}}
 In the picture above, each of the commands (DL, DP, MQ ...) represents an ion optics element. (For a complete reference of the commands used in the cosy script, one has to refer to the manual). Here in the step 3 of [[https://wikihost.nscl.msu.edu/JIOSS/lib/exe/fetch.php?media=project_for_the_jina_ion_optics_for_recoil_separator_school_v4.pdf|this project]], what we want is very simple:a drift, 45-degree dipole magnet with a 1 meter bending
 radius and a drift. So we modify this part of the script as shown in the picture below:
@@ Line 40: / Line 41: @@
 **Q4.**
-In step 4, we calculate the reaction kinematics for the 15O(a,g)19Ne reaction at 57MeV (~3MeV/u) in the lab system.
+In step 4, we calculate the reaction kinematics for the 15O(a,g)19Ne (Q=3528.47MeV) reaction at 57MeV (~3MeV/u) in the lab system.
 {{ :3mev15o.png?direct&400 |}}
-The energy spread in this case is about +-2% (maximum energy acceptance of SECAR is +-3.1%), and the angular spread is ~ +-10mrad (maximum angular acceptance of SECAR ~ +- 25mrad). At this energy the reaction products fit in our systems acceptance without any problem. However, at lower beam energies the energy spread becomes larger. The estimated minimum energy for fitting the acceptance is ~0.5MeV/u in the lab system.
+The energy spread in this case is about +-2% (maximum energy acceptance of SECAR: +-3.1%), and the angular spread is ~ +-10mrad (maximum angular acceptance of SECAR: +- 25mrad). At this energy the reaction products fit in our system without any problem.
+The maximum energy that we can go until we reach the maximum energy acceptance of SECAR is ~8.2 MeV/u.
+For reaching the maximum angular acceptance we need energies above 20MeV/u.
+* all energies are in the lab system.
+{{ :gammas19ne.png?direct&400 |}}
 --------------
@@ Line 78: / Line 89: @@
 For getting the correct parabola one should plot the quantity K=Gradient*Leff/Brho on the horizontal axis.
-By repeating the process using the above corrections we got: epsilon=0.45mm*mrad
+By repeating the process using the above corrections we got: epsilon=0.47mm*mrad
 By using more precise fit parameters in the calculation (excel returns rounded values) the number should go closer to 0.3mm*mrad
@@ Line 84: / Line 95: @@
 The nominal value of epsilon according to the ".fox" file is: epsilon=XX*AX= 0.001*0.0002 = 0.2 mm*mrad
-You can perform these calculations using this spreadsheet:
+You can perform these calculations using this spreadsheet: {{ :tripleg_emit.xlsx |}}
-{{ :tripleg_emit.xlsx |}}

JINA-CEE ION OPTICS SUMMER SCHOOL: JIOSS 2018

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