ID |
Date |
Author |
Category |
Subject |
Year |
287
|
Tue Feb 2 13:59:00 2021 |
Jan | Detectors | DSSD installation and alignment | 2021 |
The DSSD has been exchanged and aligned in
November 2020. After bakeout at 140°C
(externally, 120°C at internal temp. Sensor)
for more than a week, the vacuum in the setup
is roughly 4.5e-10 mbar.
After the bakeout the detector had to be
realigned, it was lower by 1-2 mm. Using the
line laser the realignment was done by
touching only the screws on the far part of
the base of the flange. These screws have been
thightend by about a 1/4 turn after releasing
the headless positioning screw accordingly. |
28
|
Wed Nov 6 14:13:53 2019 |
Jan, Laszlo | Detectors | DSSSD - 1st movement - realignment | |
We moved the new detector installation for the first time slowly into the dipole chamber.
The alignement seems to be pefect, no distortion or vertical movement of the detector-arm was observed from the window flange.
The vacuum on the detector side went up from 2e-10 mbar to about 5e-9 mbar.
On the ring side it was 3e-11 mbar befor and 1e-10 mbar after movement.
The extreme positions possible (Endlage) are:
max out: -10613
max in: -7
These are the absolute positions in units of 0.1 mm
It has to be noted that after bakeout a realignment of the detector was needed in order to have it centered in vertical dimension. However, this realignment has been only slight turns of the base flange alignment screws. In detail, the two inner "Sechskantschrauben" below the bellow have been loosed slightly, while the outer two have been tightend. Additionally, the small "Madenschraube" on the outside has been loosend by 1/4 turn.
In result the detector could be raised in vertical position by about ~5mm (jugded by eye).
The effect of small turning on the screws is extreme on the detector position! Be careful when re-adjusting. |
283
|
Fri Jun 5 14:06:15 2020 |
Laszlo | Detectors | DSSSD and SCRAPER position estimate for Xe and Te experiments | 2020 |
We don't know the exact absolute positions of the detector (+scraper) and the beam. However, what we have to know is only these two relative positions respect to each other. To get this distance I use two methods:
1, combining the infos from the set position during the beamtime + the measured pg peak position on the detector. The pg peak position is defined only by the eye (because of the low number of counts in every case, it doesnt make much sense to make fits). Since we rely on the detector resolution, we would be never more accurate than ~ +/-1.5mm anyhow. The active area of the detector is 49.5x49.5mm2 with a 45° tilt in y.
2, MOCADI simulation of the beam and the pg peak. This is used only as a crosscheck.
3, The scraper had a small angle in y direction causing ~0.5cm shift to the upper direction. the length of the scraping edge is 7cm
-124Xe with scraper measurement:
- measurement
d1 = moved back from beam = 15 +/-.5 mm
d2 = DSSSD frame width = 8.85 mm
d3 = pg center on DSSSD = 7-7.5 bin = 21.7-23.2 mm = avg = 22.5 mm
--> pg from beam in x = -46.4mm +/- 1.5mm
--> pg on DSSSD from center ~ -3.28mm +/- 1.5mm
- simulation
x = -46.5 mm
y = 0 mm
- detector active area position
x = (-73.35mm) - (-23.85mm)
y = (-14.2195mm) - 23.5125mm
- SCRAPING: x=-35mm +/-0.5mm away from beam
y=(-20mm) - (40mm)
-118Te:
- measurement
d1 = moved back from beam = 16 +/-.5 mm
d2 = DSSSD frame width = 8.85 mm
d3 = pg center on DSSSD = 7.5 bin = 23.2 mm
--> pg from beam in x = -48.05mm +/- 1.5mm
--> pg on DSSSD from center ~ -3.28mm +/- 1.5mm
- simulation
x = -48 mm
y = 0 mm
- detector active area position
x = (-74.35mm) - (-24.85mm)
y = (-14.2195mm) - 23.5125mm
- SCRAPING:
x=-35mm +/-0.5mm away from beam
y=(-20mm) - (40mm)
notes during beam-time:
https://elog.gsi.de/esr/E127/97?suppress=1 |
Attachment 1: SP54120060514100.pdf
|
|
Attachment 2: DSSSD_new1.pdf
|
|
Attachment 3: IMG_20200321_025644.jpg
|
|
387
|
Sat May 22 16:28:10 2021 |
Laszlo | General | DSSSD movement | 2021 |
The DSSSD is moved back to its measurement position(-25mm). |
37
|
Tue Mar 10 08:52:34 2020 |
Jan | Detectors | DSSSD positioning | |
To find a good Si position, we need to follow a procedure similar to this:
1. Si in max-in position
2. find distance of beam by scraping with detector from inside
--> zero position
3. from this zero, we need to set a distance of about 1.5 cm to the inside (as shown in the sketch below)
It is likely that this position is not compatible with the complete ESR cycle (e.g. we scrape beam with det. during deceleration).
The solution is to move the beam closer to the detector after deceleration. There are two feasible methods to do this:
A. make a local bump in the dipole
--> check new zero and det. position again, as sketched above
--> in 2016 this method didn't allow to go close enough to the detector, eventually we used:
B. global orbit change (by magnet ramp) + target bump (to keep overlap)
--> this takes a bit more time to set up and also the cycle will be longer at low energies (critical due to life-time)
--> method A is preferred, but might not be strong enough
This needs to be checked and repeated for each new beam setting. |
Attachment 1: optimum_detector_position_2.jpg
|
|
106
|
Sat Mar 21 06:02:22 2020 |
Tino, Oliver | General | Detector filling | |
Run stopped for detector fillings |
478
|
Wed May 26 20:34:50 2021 |
Ragan, Thanassis | Detectors | Detector filling | 2021 |
Jan is filling the detector after run0137. |
29
|
Fri Nov 15 10:46:12 2019 |
Laszlo | Detectors | Detector movement from HKR | |
To move the detector remotely from the HKR:
-go to a desktop of a HKR computer
-right click: "App Launcher PRO"
(-you have to give some password at this point?)
-within the program go to "Development->ProHelper"
-write the name of our slow control unit in the field Nomen: "GE01DD4AS"
-There are 4rows, the middle two called: "Read props", "Write props"
-In "Read props" open "rposiabss" -> if you hit here the refresh button it will show only the SET position
-In "Read props" open "rposiabsi" -> if you hit here the refresh button it will show the REAL-TIME position of the detector
-In "Write props" open "wposiabss" -> here you can set the absolute position of our detector (one click is already enough to execute the command).
most OUT of the ring position: -10613 [0.1mm] in absolute
most IN into the ring position: -7 [0.1mm] in absolute
The value can have as big step size as we want contrary to relative movement, when you are limited to something like 20cm.
To close the program just simply hit the "x" buttons. |
Attachment 1: IMG_20191114_135600.jpg
|
|
282
|
Tue May 19 16:48:15 2020 |
Laszlo | General | E127 beamtime overview | |
Here is a representation how was the time management during E127. The time, what we could spend with measuring the 118Te(pg), was ~20% comparing to the given 6days. |
Attachment 1: E127_beamtime_overview.png
|
|
Attachment 2: E127_beamtime_overview.pdf
|
|
249
|
Mon Mar 23 14:12:54 2020 |
Ragan | Runs | E127 experiment stops | |
close file : run104 (14:12:44)
E127 experiment finishes on a successful note )) Congratulations to the entire team !! |
569
|
Mon May 31 10:08:42 2021 |
Jan, Sophia | Runs | E127b runsheet | 2021 |
|
Attachment 1: e127b_runsheet.ods
|
208
|
Sun Mar 22 23:19:23 2020 |
Michael | General | ESR Vacuum readings | |
|
Attachment 1: ESR_Vakuum2020-03-22-2318.PNG
|
|
226
|
Mon Mar 23 06:49:46 2020 |
Shahab | Runs | ESR kicker also has some problems | |
|
438
|
Tue May 25 07:51:48 2021 |
Jan | Accelerator | ESR stacking cycle length | 2021 |
The full cycle length of ESR with 30 stacks is about 7:45 minutes, out of which 15.5 sec are with target switched ON.
This is without CMB/HTD in parallel. |
573
|
Wed Jun 23 12:29:35 2021 |
Jan, Sophia | Calibration | Efficiency of the x-ray Detectors | 2021 |
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 |
Attachment 1: Effizienz_x_ray_GEM1800_90.png
|
|
Attachment 2: Effizienz_x_ray_GEM3000_145.png
|
|
Attachment 3: Effizienz_x_ray_GLP_35_ohne33keV.png
|
|
575
|
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 |
215
|
Mon Mar 23 01:53:59 2020 |
Shahab | Runs | Empty shots in ESR | |
since about 01:40 AM, there is no beam in ESR. .
stopped data acquisition
OPs are working on it. After searching, OPs decided that something is wrong with ESR. |
126
|
Sat Mar 21 12:42:21 2020 |
Ragan | General | Entry to ESR for MCP detector | |
Pierre Michel and Laszlo go inside the ESR for switching on the MCP detector so that the photons from the gas jet and secondary beam interaction can be seen.
Close file: run061 |
125
|
Sat Mar 21 12:32:00 2020 |
Laszlo | General | Estimated target thickness | |
Target thickness must be like 5mm (was measured with a moving thin wire)
The beam thickness is small because of the low intensity
Maybe we hit the target a bit offset --> less rate?
We might have the option to increase the target 1magnitude more, but this might not help because we can kill the beam
with this.
I have the impression we just simply have less number of stored ions like 10^4 or evem less...
Yury: "we are unsure about the settings and desperately seek for any means of additional diagnostics" |
496
|
Thu May 27 13:26:35 2021 |
Jan | Accelerator | FRS degrader failure | 2021 |
Maybe, our degrader in FRS was removed by hand at (~13:40 26/05/21)
It is put back now (~13:10 27/05/21)
All runs taken in this period have to be double checked!
However, the xray lines from this night show Te for k_alpha and K-KREC
It is also possible that the readout of this degrader motor was just wrong due to its state as hand-controlled. |