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New entries since:Thu Jan 1 01:00:00 1970
ID Date Author Category Subject
  154   Wed Jun 30 14:48:54 2021 OliverGeneralData taking - and not...
We just started data taking. But a few minutes later the main experiment needed to do some adjustements to the beam. This interrupts us for a couple of minutes...
  153   Wed Jun 30 13:57:14 2021 Yuri, SergeyAcceleratorsextupoles + scraper positions
After setting up on 70Se
Sextupoles were adjusted to optimize the resolution of the 70Se peak. Set values are in the ESR logbook.
The SIS energy was shifted up to increase the number of 70Se.
Esis original = 445.68 MeV/u
Esis now = 451.68 MeV/u (+6 MeV/u)

See attached pictures

scrapers: 
GE01DS_HI =  -58mm
GE01DS_HA = +130mm (fully open)
GEEXDD2_S = -0.5mm
GEEXDS2HA = -11.2mm
  152   Wed Jun 30 13:05:08 2021 Rui-Jiu ChenAnalysisID of 70Se
This is the latest ID of 70Se setting.
  151   Wed Jun 30 13:04:40 2021 ShahabRuns245 Amplifier on
turned on extra 20dB amplifier for the 245 Resonator around 12:32 
  150   Wed Jun 30 12:35:53 2021 Rui-Jiu ChenAnalysisChange reference level to -20dBm. Turn of amplifier.
SC_2021-06-30_12_35_52
IQ_2021-06-30_12_35_43
Reference level=-20dBm
  149   Wed Jun 30 12:26:58 2021 Rui-Jiu ChenAnalysisNTCAP start.
SC_2021-06-30_11-00-12
IQ_2021-06-30_11-00-12
reference level -80dBm.
Amplifier is off.
  148   Wed Jun 30 09:04:50 2021 Yuri, MarkusAcceleratorStatus
1) Over night the source was conservated. It is being restarted now.
2) The approximated amount of Gas in this bottle shall allow for running until tomorrow morning (~24 h). There is still another bottle in reserve (1 l) and one reserve from GANIL (0.5 l).
3) Beam-time coordinator suggests to run until the gas is over, i.e., up into the weekend.
  147   Wed Jun 30 08:59:37 2021 YuriAccelerator70Se setting
X(9Be)=1.815 g/cm2 (adjusted in primary beam setting)

Gamma_t=1.3956
E(70Se)=368.499 MeV/u
Br(70Se)=6.21993 Tm

Pre-drilling:
E(78Kr)@Br(70Se)=337.461 MeV/u
E(SIS) = 415.792 MeV/u

Fragment Setting:
E(SIS) = 445.68 MeV/u
  146   Wed Jun 30 02:12:46 2021 ShahabRunsstill no beam in ESR: quadrupole magnets are down
still no beam in ESR: quadrupole magnets are down
  145   Wed Jun 30 01:38:20 2021 ShahabRunsbeam is back from Linac but not in the ESR
  144   Wed Jun 30 00:20:10 2021 Rui-Jiu ChenAnalysisID of 70Se setting on May
This is an old spectrum which was recoded on May.
  143   Wed Jun 30 00:12:55 2021 Rui-Jiu ChenAnalysisthe ID of 72Ge setting
  142   Tue Jun 29 21:15:01 2021 Kanika, ShahabRunslost beam problem Unilac
cooling water in UNILAC is out
  141   Tue Jun 29 21:12:15 2021 Kanika, ShahabRunsMoving the resonance frequency of the 245 MHz resonator
moving in the plungers:

before: 400
after: 200
  140   Tue Jun 29 21:10:30 2021 ShahabRuns72-Ge setting
the new setting is roughly 400 khz lower in frequency.
Previous beam time Ge was on 243.100 now it is on 242.74

we decided to use the higher harmonic:

expecting it on 244.66 MHz
  139   Tue Jun 29 20:40:55 2021 Rui-Jiu ChenDAQstart NTCAP
Carrier Frequency:245MHz.
IQ rate 20MSamples/s
Reference level:-90 dBm
SC_2021-06-29_20-38-27
IQ_2021-06-29_20-38-27
  138   Tue Jun 29 20:13:58 2021 Helmut, Sergey, YuriAcceleratorchange to predrilling an 72Ge
After optimisation of sextupoles we found a scraper position which makes a narrow peak and keeps 20% of the injected beam.
  GEEXDS2HA = +2.0 mm (out is +130mm)
  GE01DS_HI = -75 mm  (out is -130mm)
removed scrapers again for predrilling.

We agree on gamma_t = 1.3956, E/m = 368.50 MeV/u.
Then for 78Kr at Brho = 6.79675 Tm of isoc 72Ge 
E-SIS = 466.63 MeV/u, assume target of 1815 mg/cm² Be
after target E/m = 393.024 MeV/u
In ESR-Modi set for same E/m but different m/q (m=72, Z=q=32)

Injection looks good like before with isochronous 78Kr we go directly to the next step
72Ge with E-SIS = 440.16 MeV/u to get 72Ge at gamma_t.
  137   Tue Jun 29 10:32:10 2021 Sergey, HelmutAcceleratorcooler curves for tuning of isochronicity
Variation of quadrupole E01QS03D to change gamma_t in isoc. mode
measured with 78Kr at 368.5 MeV/u on 28.06.2021 evening.
The shape of the three curves looks very similar they would only require a different beam velocity.
But I suppose we stay with the value close to the old one (gamma_t ~ 1.3956).
  136   Mon Jun 28 18:32:49 2021 Ruijiu, ShahabDAQtrigger signal connected to NTCAP and analyzers
  135   Fri Jun 25 21:47:24 2021 YuriAnalysisIdentification
Attached are two files with a proposed particle identification.
Different colors indicate different harmonic numbers
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