HOME ESR EXPERIMENTS LABS etc
E121 E127 E132 E125 E143 laser_cooling_2021 E142 Ê128 E146 E0052 E0018 E0028
  proton-capture on 118Te, Page 29 of 29  Not logged in ELOG logo
New entries since:Thu Jan 1 01:00:00 1970
Entry  Sat Mar 21 23:07:00 2020, Laszlo, General, 1672. MCP file was (recoils) was not closed,  
1672. MCP file was  (recoils) was not closed when we refilled the Xrays and did the cable change of 90 and 145 xrays
These stored in lxg1299 local disk
Entry  Fri Mar 20 01:36:48 2020, Laszlo, General, 124Xe primary beam at 10Mev TargetON,  
We didmt see any effect on the lifetime if the target is switched on. It is because we use only hydrogen target (but why 
is.it so?)
Entry  Thu Mar 19 23:48:56 2020, Laszlo, General, 124Xe primary beam at 10Mev TargetOFF,  IMG_20200319_232647.jpgIMG_20200319_232704.jpgIMG_20200319_234450.jpg
Beam lifetime is estimated to be 11sec at least (hard to.see with the cursor the corrct values on the shottky monitor) 
but Yury says it is even 
~20sec. The particle njmbers are on the attached picture, however at 10Mev the cirrent measurement is not.really 
teustable (too low beam current)
Entry  Tue Jul 23 10:46:29 2019, Laszlo, Analysis, 124Xe pg peak fit using mixed cascade simulation,  7x
This entry is the continuation of the cascade effects on the pg peak shape entry:

https://exp-astro.physik.uni-frankfurt.de:8080/E108/475

The main point is that having more cascade makes the impulse carried by one photon smaller --> recoil cone is
smaller --> pg peak gets more centered

When one wants to make an "all-inklusive" simulation the problem comes, that there are too many populated states
after CN* decay (many are just theoretical), also many cascades afterwards as well.
Instead, one can make a "statistical approach":
 1, take an average 1st populated state after the gamma emission of the CN*.
 2, take an average of the gamma energies after the p-capture. (it includes also the photons from the CM* to the
1st state after g emission with energy of [(E_CM - Q) - E_1st_state] --> should these be excluded from the avg.
gamma energy calculation?)
 3, the excited compound nucleus first decays to 1, then cascading down with the avg energy of 2,

    number_of_cascades = E_1st_state/E_avg_gamma. 

    For the 124Xe at 7AMeV using the TALYS code the above values are:
    E_1st_state = 6.74 MeV
    E_avg_gamma = 2.75 MeV
    number_of_cascades = 2.45

To reproduce the resulting avg. pg peak, I took a 2 and a 3 cascade simulations produced by MOCADI and mixed
them as 55% of the 2-cascade and 45% of the 3-cascade for this naiv, statistical model.
Then, to test the peakshape, I fit this mixed distribution to a part our measurement data at 7AMeV after a
sloppy Rutherford background removal (the background removal can be more improved, I used this as a quick method
for now). The calculated Chi^2/NDF ~ 3, which is not a super good value, but taking into account that this is a
strongly naiv model, and the background removal can be also improved, the chi^2/NDF value can be also
interpreted as promising.
Entry  Fri Mar 20 13:21:33 2020, Jan, Laszlo, Analysis, 124Xe data of first night,  90_deg.png35_deg.png145_deg.pngimage3063.pngimage4019.png
The unpacked data of all runs from the first night (46-50) is located at
litv-exp@lxg0188:/data.local2/E127_lmd/124Xe_1st_night.root

By taking a very quick look at the Silicon xy position histo, one can identify (please not the number of counts) clusters of hits. The x=0 and x=1 strips sees the forward scattering Rutherford particles, which remained even after scraping at 3.5cm away from the beam. This idea is supported by the simulations. Backscattered Rutherford components cannot be identified simply because of their low count rate (the exact rate should be double check). The second cluster in the middle of the detector must be our pg peak. For x>=7 strip we see the pn channel. It overlaps with the pg peak both in the position and in the energy. The energy vs Xstrip histo is NOT gainmatched, yet. Hard to make statements, but so far it seem to support the conclusions based on the position histo. The energies seem to corrsepond to the simulation: forward Rutherford, pg at same level; pn is a bit below ( ~.8% energy separation of the centers). The separation in the enregy for the backscattered Rutherford should be in the range of 2%.
Entry  Sat Mar 21 23:19:14 2020, Jan, Analysis, 118Te52+ on H2-target - Xray spectrum 90 degree,  90_deg_118Te_runs64to66.png
The attached spectrum is for the 90 degree X-ray detector taken for about 3 hours with 118Te52+.
We see two peaks at ~29 keV (K-alpha) and 44 keV (K-REC).

The resolution is about 1.5 keV, and the signal-to-background ratio is also really bad.

The increase of background events at higher E might be induced by Compton scattering of a high E gamma ray from the BaF detectors, which are active and sit close by (not anymore).
Entry  Fri May 28 15:15:06 2021, Jan, Analysis, 118Te(p,g) counts runs 135 to 174, 2021 run135to174_Si_map.pngrun135to174_Si_projection.png
This is the summary of all Si data collected at 6 MeV/u until run174 before the Alvarez problem.
We have roughly 50-60 counts in the peak region.
This data corresponds roughly to 36hours of beam, which means ~1.5 to 2 counts/hour.
Entry  Mon Feb 17 08:14:44 2020, Jan, Simulations, 118Te K-REC X-ray energies,  Photonen_Kammer.pngx-ray_calculator.txt
X-ray energies of K-REC for 118Te according to
http://www-ap.gsi.de/Thomas/ap_html_research/energy/index.php

parameters 35 deg 90 deg 145 deg
8 MeV/u 47.29 keV 42.25 keV 38.17 keV
5 MeV/u 44.51 keV 40.74 keV 37.57 keV


Full results are attached
Entry  Tue May 25 11:58:30 2021, Jan, Analysis, 118(p,g) counts until run0115, 2021 run91to115_Si_map.pngrun91to115_Si_projection.png
The two attached plots show the collected Si data up to run0115.

Within this ~15h we have about ~70 counts in the peak region.

This translates to ~4.5 counts per hour.
And shall be compared to the 1 count/hour we had last year.
Entry  Tue May 25 09:53:04 2021, Oliver, Diego, Runs, (No)Run 0114, 2021 
Run0114 was started after ESR optimization but immedieatly again stopped...

at 09:52:34 on 25.05.2021
Entry  Sat Mar 21 01:44:57 2020, Laszlo, General, ,  
from the SIS side they could optimize the intensity. we gained a factor ~3. Now the SIS intensity is at 
Entry  Tue Apr 21 22:25:00 2020, Jan, Analysis, ,  
 
ELOG V3.1.5-fc6679b