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Entry  Wed Oct 13 15:15:53 2021, Jan, DAQ, root-file header for analysis, 2021 e127b.h
Attached is the header file needed for root analysis.
Entry  Wed Oct 13 15:09:04 2021, Jan, Collaboration, K-REC cross sections A. Surzhykov, 2021 DCS_Z_52_Tp_7.049MeV_NEW.datDCS_Z_54_Tp_7.049MeV_NEW.datDCS_Z_52_Tp_6.042MeV_NEW.dat
Attached are the theory K-REC cross sections as calculated by Andrey Surzhykov (August 2021).

They are done for 118Te52+ on H2 at 7.049 and 6.042 MeV/u as well as for 124Xe54+ on H2 at 7.049 MeV/u.


first column - photon angle (deg), second column - cross section (barn/sr). The results are given already in the laboratory frame.

Comment of Andrey on uncertainty:
Important question about theoretical model and, hence, accuracy of calculations. I used slightly improved "impulse approximation" that takes into account momentum and energy distribution of target electron (in initial state). By playing with the models for the Compton profile of target electron, I estimate the accuracy of calculations as 1 %. To be fair, it is rather conservative estimate. I suspect that for large emission angle (around 90 deg) accuracy is even better. But let us stay with 1 %. 
Entry  Wed Jul 14 14:46:05 2021, Jan, Sophia, Detectors, collimator geometry, 2021 10x
We have measured the collimator geometry. The annotations of the variables can be found in the attached sketch

90° Detector GEM1800 Distance[mm]
A2.4
B10.05
C2.1
D35.025
145° Detector GEM3000 Distance[mm]
A2.15
B10.05
C5.025
D35
35° Detetektor GLP-2000 Distance[mm]
A2.1
B10.05
C0
D13
Entry  Thu Jul 8 14:07:19 2021, Jan, Calibration, beam energies, 2021 CodeCogsEqn.pngCodeCogsEqn(1).png
Table of ion energies calculated from cooler parameters

nominal energyV_set V_meas I_set E_ion E_Error
6 MeV/u 3460.5 V 3364 V 50 mA 6.042 MeV/u YY keV/u
7 MeV/u 4008.3 V 3913 V 50 mA 7.049 MeV/u YY keV/u


Here is how the calculation works:

1. Find the voltage and current set values that were active during the measurement cycle.

2. These are only SetValues. For the current this is fine, but for the voltage you have to subtract an offset. This offset comes from the power supply and changes over time. It is measured regularly and the present offset you have to inquire with the ESR/cooler crew. For our beam time E127b in 2021 the offset is:

V_offset = -95 +/- ?? V (only for E127b)

The uncertainty has still to be discussed.

3. The space charge of the electron beam reduces the effective voltage seen by the electrons and thus reduces their energy. You have to calculate the space charge potential Phi_0 on the beam axis using the following formular:



using R_tube = 10cm and R_e-beam = 2,54 cm and all constants, you arrive at the ESR specific equation:



4. Now calculate effective Voltage and electron energy:

V_eff = V_set + V_offset + Phi_0

This time we measured the effective voltage for each energy, so we can actually use this values (V_meas) instead of V_set + V_offset.

E_e = e * V_eff

5. With E_e you can now calculate the ion energy by using the definition of the Lorentzfactor gamma:

gamma - 1 = E_kin/(m_0 * c^2)

In equilibrium, the left side of the equation is equal for both, electrons and ions in the cooler, leading to:

E_ion = E_el * M_ion/M_el

which gives the total energy of the ions.

NOTE:
In principle, this should be an iterative calculation, since the potential depends on beta and is then used to calulate beta or ion energy. But in practice a single iteration is precise enough, if beta was a good estimate.
Entry  Thu Jul 8 13:39:34 2021, Jan, Calibration, Electron cooler parameters, 2021 
Below are the results from the e-cooler voltage offset measurments done by Regina Hess et al. using the voltage divider (VD).

--7 MeV-- 
Sollwert GECEBG1E: 4008.3 V     
Measured at VD: 3913 V
Offset: -95.3 V

--6 MeV-- 
Sollwert GECEBG1E: 3460.5 V     
Measured at VD: 3364 V 
Offset: -96.5 V

Below are the cooler parameters from ParaModi for our production runs.

--7 MeV/u--
UE: 3842.7V
IE: 50mA
BG1E: 4008.7V
BG1E dU: 120V

--6 MeV/u--
UE: 3290.833V
IE: 50mA
BG1E: 3460.4809V
BG1E dU: 120V

--energy calculation--
as described here 

-- uncertainty --
for E108b we agreed on 10%
maybe further discussion is needed
Entry  Thu Jun 24 09:43:01 2021, Jan Glorius, DAQ, Unpacker, 2021 
The unpacker used for the production runs of E127b is located at 
/u/litv-exp/unpacker/unpackexps/e127_TO_2021_with_ECL

It is also aliased for litv-exp user as: E127_unpack

This is for the data structure as documented here:
https://elog.gsi.de/esr/E127/346

As of now, this is compiled for ROOT v6-18-04 located here:
/cvmfs/csee.gsi.de/root/618-04/bin/root
Entry  Wed Jun 23 12:29:35 2021, Jan, Sophia, Calibration, Efficiency of the x-ray Detectors , 2021 Effizienz_x_ray_GEM1800_90.pngEffizienz_x_ray_GEM3000_145.pngEffizienz_x_ray_GLP_35_ohne33keV.png
For the x-ray detectors, efficiencies have been measured, before and after the experiment was performed. 
The preliminary results of the determined efficiencies can be seen in the attached plots 
Entry  Tue Jun 8 15:06:17 2021, Shahab, Analysis, Beam lifetime, 2021 pgamma_lifetime.001.pngpgamma_lifetime.002.png
measured beam lifetime after the second deceleration using parallel plate Schottky detector and the RSA5103 spectrum analyser. Analysis code can be found here:

https://github.com/xaratustrah/e127_scripts/

The plots here were produced using the script:

https://nbviewer.ipython.org/github/xaratustrah/e127_scripts/blob/main/lifetime_calculator.ipynb


UPDATE 2022-06-30:

Life times have been slightly corrected. Please see attachment.


Filename	Start Frame	Correct Lifetime [s]	Mean [s]
pgamma_lifetime-2021.05.25.21.56.37.593_on.tiq	29500	1.43	
pgamma_lifetime-2021.05.25.22.02.16.618_on.tiq	29500	1.55	1.49
pgamma_lifetime-2021.05.25.22.07.22.369_off.tiq	53500	1.75	
pgamma_lifetime-2021.05.25.22.13.24.787_off.tiq	34900	1.89	1.82
Entry  Wed Jun 2 09:14:04 2021, Jan, General, Telegram Chat Export, 2021 E127_TelegramChat.pdfE127_TelegramChat_json.zip
Attached is the exported Telegram chat.
There is the simple PDF and the zip-file containing the chat in json-format as well as all media files.
Entry  Mon May 31 14:38:33 2021, Sophia, Calibration, Runlist for X-ray detector calibrations after the experiment, 2021 Kopie_von_E127_Runlist-calibrations-4-3-1.xlsx
The by Jacobus Swartz created table in entry 335 extended by the calibration after the experiment.
Entry  Mon May 31 10:08:42 2021, Jan, Sophia, Runs, E127b runsheet, 2021 e127b_runsheet.ods
 
Entry  Sun May 30 14:48:09 2021, Jan, Sophia, Calibration, run0215 - crap, 2021 
 
Entry  Sun May 30 14:40:55 2021, Jan, Sophia, Detectors, real detector assignment, 2021 
************************************
GEM1800 @ 90deg (xray1) 
GLP2000 @ 35deg (xray2)
GEM3000 @ 145deg (xray3)
************************************

Was noted wrongly in most calib runs.
Entry  Sun May 30 14:38:09 2021, Jan Glorius, Calibration, run0216 - X-calib. 90-ba 35-pb, 2021 
Efficiency calibration in ESR after experiment

************************************
GEM1800 @ 90deg (xray1) 
GEM3000 @ 35deg (xray2)
GLP2000 @ 145deg (xray3)
************************************


Detectors: 90 + 35 
Source @ 90deg: 133Ba_lo
Source @ 35deg: 210Pb
Distance: each
Start time: 14:46:46 - 30.05.2021
Stop time:  20:11:08 - 30.05.2021

file name: e127b_run0216.lmd
avrg. rate: 330Hz
dead-time:  3%
Entry  Sun May 30 13:23:26 2021, Jan Glorius, Calibration, run0214 - X-calib. 90-ba 145-ba 35-am, 2021 
Efficiency calibration in ESR after experiment

************************************
GEM1800 @ 90deg (xray1) 
GEM3000 @ 35deg (xray2)
GLP2000 @ 145deg (xray3)
************************************


Detectors: 90 + 145 + 35 
Source @ 90deg: 133Ba_lo
Source @ 145deg: 133Ba_hi
Source @ 35deg: 241Am_hi
Distance: each
Start time: 13:22:38 - 30.05.2021
Stop time:  14:28:09 - 30.05.2021

file name: e127b_run0214.lmd
avrg. rate: 1150Hz
dead-time:  8%
Entry  Sun May 30 11:32:06 2021, Jan Glorius, Calibration, run0213 - X-calib. 90-am 145-pb 35-ba, 2021 
Efficiency calibration in ESR after experiment

************************************
GEM1800 @ 90deg (xray1) 
GEM3000 @ 35deg (xray2)
GLP2000 @ 145deg (xray3)
************************************


Detectors: 90 + 145 + 35 
Source @ 90deg: 241Am_hi
Source @ 145deg: 210Pb
Source @ 35deg: 133Ba_hi
Distance: each
Start time: 11:31:47 - 30.05.2021
Stop time:  13:10:14 - 30.05.2021

file name: e127b_run0213.lmd
avrg. rate: 700Hz
dead-time:  6%
Entry  Sun May 30 10:24:20 2021, Jan Glorius, Calibration, run0212 - X-calib. 90-pb 145-am, 2021 
Efficiency calibration in ESR after experiment

************************************
GEM1800 @ 90deg (xray1) 
GEM3000 @ 35deg (xray2)
GLP2000 @ 145deg (xray3)
************************************


Detectors: 90 + 145 
Source @ 90deg: 210Pb
Source @ 145deg: 241Am_hi
Distance: each
Start time: 10:24:55 - 30.05.2021
Stop time:  11:19:29 - 30.05.2021

file name: e127b_run0212.lmd
avrg. rate: 250Hz
dead-time:  2%
Entry  Sun May 30 07:26:14 2021, Oliver, Diego, Jan, Runs, Run 0211, 2021 
No. of stacks: 10 00:52:43
length SC10: 2x 5.5s
bump ge01sq2f (sc10): -20 mm
bump target (sc10): -12.8 mm

open file : e127b_run0211.lmd

beam: 118Te52+
energy: 6 MeV/u
cooler voltage:

purpose:
Fragment beam measurement (beating the record of rad. beam pg-measurement)

Detector position (Si): -25 mm
GE01DD1IG position (Scraper): +6.0 mm

run start: 07:25:54 30.05.2021
run stop: 08:04:19 30.05.2021
_______________________________________________________________________________

ON Rates
Si_ON_bdt: ~ 0 Hz
Xray_ON_bdt: ~ 110 Hz
BaF_OR: ---

Si voltage: 100.0 V
Si leakage current: 400 nA


SIS particles before: 2.7e9 (one shoot)
ESR current at injection: 2.7e6 (stacked)
ESR particles after decel.: not measurable
Target ON density: 8.0E13
Entry  Sun May 30 06:32:43 2021, Oliver, Diego, Jan, Runs, Run 0210, 2021 
No. of stacks: 10 00:52:43
length SC10: 2x 5.5s
bump ge01sq2f (sc10): -20 mm
bump target (sc10): -12.8 mm

open file : e127b_run0210.lmd

beam: 118Te52+
energy: 6 MeV/u
cooler voltage:

purpose:
Fragment beam measurement (beating the record of rad. beam pg-measurement)

Detector position (Si): -25 mm
GE01DD1IG position (Scraper): +6.0 mm

run start: 06:32:16 30.05.2021
run stop: 07:12:04 30.05.2021
_______________________________________________________________________________

ON Rates
Si_ON_bdt: ~ 0 Hz
Xray_ON_bdt: ~ 110 Hz
BaF_OR: ---

Si voltage: 100.0 V
Si leakage current: 400 nA


SIS particles before: 2.7e9 (one shoot)
ESR current at injection: 2.7e6 (stacked)
ESR particles after decel.: not measurable
Target ON density: 8.0E13
Entry  Sun May 30 05:32:42 2021, Oliver, Diego, Runs, Run 0209, 2021 
No. of stacks: 10 00:52:43
length SC10: 2x 5.5s
bump ge01sq2f (sc10): -20 mm
bump target (sc10): -12.8 mm

open file : e127b_run0209.lmd

beam: 118Te52+
energy: 6 MeV/u
cooler voltage:

purpose:
Fragment beam measurement (beating the record of rad. beam pg-measurement)

Detector position (Si): -25 mm
GE01DD1IG position (Scraper): +6.0 mm

run start: 05:32:09 30.05.2021
run stop: 06:32:13 30.05.2021
_______________________________________________________________________________

ON Rates
Si_ON_bdt: ~ 0 Hz
Xray_ON_bdt: ~ 110 Hz
BaF_OR: ---

Si voltage: 100.0 V
Si leakage current: 410 nA


SIS particles before: 2.5e9 (one shoot)
ESR current at injection: 2.5e6 (stacked)
ESR particles after decel.: not measurable
Target ON density: 8.0E13
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