Fri Mar 27 13:40:54 2020, Ragan, General, NTCap start and shutdown information
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The attachment contains information on how to start and shutdown NTCap and bridge computer. |
Fri Mar 27 19:51:37 2020, Ragan, General, ESR Machine
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By changing the tune to Qx=2.33, Qy=2.36 the momentum acceptance was significantly improved. A variation of the cooler voltage of 10300 V was possible without beam loss. That corresponds to a momentum acceptance of 2.7 %. That should provide good conditions for longitudinal stacking.
Thanks to the ESR team ! |
Fri Mar 27 19:59:09 2020, Ragan, General, Beam stacking in ESR is achieved
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Thanks to Sergey and Markus, stacking of primary H-like 206Pb81+ beam in ESR is achieved.
The stacking of the primary beam was established. There is continuous cooling on the injection orbit by stochastic cooling and by electron cooling on the stack orbit. (Time controlled operation of stochastic cooling could not be achieved due to controls issues). After stchastic cooling on the injection orbit the rf system decelerates the beam by 1.5 % in momentum and at the lower momentum electron cooling keeps the beam. The DC trafo shows accumulation of 10 injections of primary low intensity Pb81+ beam. Losses during the accumulation seems to be small. |
Fri Mar 27 20:05:43 2020, Ragan, General, H2 gas jet ready
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Thanks to Nikos, stable H2 gas jet target with 10^14 particles/cm^3 is ready.
(More information can be found on: https://ulpc24.gsi.de/cgi-bin/jet.py?gasart=Helium ) |
Fri Mar 27 20:52:31 2020, Ragan, General, Plans for the measurement with 206Pb81+
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We plan to measure:
1. Lifetime of H-like 206Pb81+ beam with two electron cooler currents:
a) 200 mA
b) 10 mA (so that recombination rate is less)
using MWPC (capture detector in outer pocket) and CsISiPHOS (loss detector in inner pocket).
2. To find the efficiency of the MWPC. |
Sat Mar 28 01:14:19 2020, Ragan, General, Cross-section for capture and ionisation of 206Pb81+ with H2 target
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Cross-section for capture and ionisation of 206Pb81+ with H2 gas jet target are calculated using GLOBAL code.
The ionisation (on CsISiPHOS) and capture (on MWPC) trigger rates are calculated for 206Pb81+ beam with 10^6 particles revolving in ESR ~2 MHz frequency with H2 gas jet target density ~ 10^14 particles/cm3. |
Sat Mar 28 04:32:15 2020, Ragan, Detectors, Ionisation events on DSSSD
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XY co-relation of DSSSD showing 206Pb82+ beam hitting the CsISiPHOS detector present in the inner pocket of ESR after the first dipole after the gas jet. 206Pb82+ is
produced by ionisation of
206Pb81+ due to interaction of beam with the gas jet. |
Sat Mar 28 04:50:34 2020, Ragan, Detectors, MWPC
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Alex and Pierre-Michel applied 1500 V to the anode and adjusted the threshold in Messhute.
x1 signal was small & noisy and rest of the signals were fine. |
Sat Mar 28 11:00:14 2020, Ragan, RuiJiu, Mei, Yuri, Tino, Detectors, Movement of detector
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10:51 am the CsISiPHOS is moved to 65 mm from 60 mm.The spot on the DSSSD is changed by 5 mm which confirms the hit of the beam.
11:05
Detector is moved back to 60 mm. |
Sat Mar 28 11:07:49 2020, Ragan, RuiJiu, Tino, , General, Nikos is changing gas jet target
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The gas jet target is now being changed from H2 to Ar by Nikos. |
Sat Mar 28 11:20:10 2020, Ragan, RuiJiu, Mei, Yuri, Tino, General, Reducing beam intensity in ESR
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Yuri reduces beam intensity in the ESR to reduce the countrate on the detectors. |
Sat Mar 28 11:28:11 2020, Ragan, RuiJiu, Mei, Yuri, Tino, General, ESR open
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ESR is open now |
Sat Mar 28 12:19:21 2020, Ragan, RuiJiu, DAQ, Change of the polarity of Amplifiers
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Since last night, the signals from the p-side of all the Si pads were seen as negative on picoscope.
The signals from DSSSD, all n-sides of Si pads and CsI were positive which all are in MSCF-5.
Thus, I and RuiJiu, changed the polarity jumpers of MSCF 1,2,3 and 4(all the four jumpers inside the mentioned MSCF) and now hope to see positive signals from the p-side of all the Si pads. |
Sat Mar 28 13:09:11 2020, Mei,Yury, Tino, Ragan, Ruijiu, General, Shift plan
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From Yury,
For now, measure the beam life time with 3 different electron current in the e-cooler,i.e. 200mA(default), 10mA, and 20mA. For each current, 4 sets of 30mins long measurements shall be taken.
Starting from 9pm Helmut and Sergey will come for setting up FRS |
Sat Mar 28 13:19:56 2020, Ragan, Runs, Template
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beam:
energy:
storage time:
purpose: data with TARGET ON
Detector position (CsISiPHOS): mm
Detector position (MWPC): mm
run start at xx:xx , first file: run0xxx.lmd
run stop at xx:xx , last file: run0xxx.lmd
_______________________________________________________________________________
time:
I_cooler = mA
HV1
CH1 voltage: 60V
CH1 leakage current: uA
CH2 voltage: 60V
CH2 leakage current: uA
CH3 voltage: 60V
CH3 leakage current: uA
CH4 voltage: 60V
CH4 leakage current: uA
HV2
CH1 voltage: 60V
CH1 leakage current: uA
CH2 voltage: 60V
CH2 leakage current: uA
CH3 voltage: -50V
CH3 leakage current: uA
CH4 voltage: -160V
CH4 leakage current: uA
SIS particles before:
ESR particles after stacking:
Number of stackings:
Target ON density:
Target on time for measurement:
NTCAp file:
IQ_2020-03-27_21-02-31/0000xxx.iq.tdms
SC_2020-03-27_21-02-31/0000xxx.iq.tdms
copy and repeat the above (below the line) every 30 minutes |
Sat Mar 28 14:19:24 2020, Ragan, RuiJiu, Mei, Yuri, General, Instructions to change the electron cooler current
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Attached are the instructions on how to change the electron cooler current for the lifetime measurements of 206Pb81+ beam (interaction with residual gas and electron cooler). |
Sat Mar 28 15:07:40 2020, ruijiu, DAQ, start run
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Sat Mar 28 15:19:23 2020, ruijiu, , start run e121_run_0236.lmd
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store 206Pb81+ beam inside ESR and measure its halflife.
The HV of detector is off.
Start DAQ to record the ESR current in lmd file.
Nik is optimizing the gas jet target. So this file is still test run. |
Sat Mar 28 15:23:05 2020, Alex, Ragan, Mei Bai , General, beam lifetime measurement
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We see two species in the Schottky spectra during the beam lifetime measurement without the target. The one (probably the primiary beam) is significantly better cooled than the other.
So, we were wondering what is the other beam? Maybe the recombined ones? |
Sat Mar 28 16:09:50 2020, Alex, General, no beam in the ESR
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Ragan and Ruijiu went in the ESR for short time to fix something with the slow control of the silicon detector.
After this, there is no beam in the ESR. |