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| Nuclear hyperfine mixing in 229Th89+ 2025 |
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Message ID: 32
Entry time: Sat Jun 21 00:52:07 2025
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| Author: |
Carsten |
| Category: |
Accelerator |
| Subject: |
Summary of the last days (bunches wiht several isotopes still in ) / frequency of the |
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Initially, we has very low SIS beam intensities in the 1e8 region. Setting up ESR wiht Stacking etc. turned out to be extremly tedious for the ESR crew.
Yet, they managed to get stochastic ooling working early on.
Accumulation with the new "stochstic cooling only" scheme essentially does not saturate even after 40 injections or so.
One problem was that the beam often got lost at deceleration and not reliable / reproducable conditions could be achieved.
Also the secondary beam and partilce ID could finally be established (see earlier posts). During deceleration often the partilces were got lost again.
In the decelerated bunch at least 7 isotopes were decelerated (and not only one):
The frequencies were
@ 400 MeV/u in SC 3:
[1] 242.27986 MHz
[2] 242.82623 MHz + 27.5 kHz
[3] 242.853 MHz + 54.375 kHz 229Th
[4] 242.878 MHz + 79.375 kHz
[5] 242.936 MHz + 137.5 kHz
[6] 242.959 MHz + 160 kHz
[7] 242.982 MHz + 183.75 kHz
decelerated to 190 MeV/u:
[1] 243.6925 MHz
[2] 243.72213 MHz + 29.6 kHz
[3] 243.750 MHz + 57.375 kHz 229Th --- Reference on Schottky scope
[4] 243.7768 MHz + 84. kHz
[5] 243.8376 MHz + 145 kHz
[6] 243.863 MHz + 170.6 kHz
[7] 243.687 MHz + 194.625 kHz
Thursday night (19.6. -> 20.06.) a first scraping was established.
In order to cleanly scrape the peaks Sergey Litvinov devised a new pattern:
At the low energy (190 MeV/u) the bunch is unpacked, cooled, scraped and rebunched for the measurement.
Some details of th eabove can be found in the acclerator log.
The problem with the beam losses were solved with large cooling phases at the end of the accumulation cycle. |