ID |
Date |
Author |
Category |
Subject |
Year |
571
|
Wed Jun 2 09:14:04 2021 |
Jan | General | Telegram Chat Export | 2021 |
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. |
2
|
Thu Jan 17 08:45:43 2019 |
Jan | Detectors | Micron W1 DSSSD - technical information | |
Attached are the spec sheets and design drawings of the new DSSSDs from Micron.
Additionally, the 3D model made by Laszlo is also attached as stp and dwg. |
7
|
Wed Jun 5 11:29:13 2019 |
Jan | Detectors | position/channel calib. | |
This is the first position calibration done with the detector installed in the holder. The goal is to assign rough positions (top/bottom/left/right) to PreAmp- and Shaper-channels.
PreAmp Channel | polarity | position
|
1-1 (Y-1) | neg. | bottom
|
1-16 (Y-16) | neg. | top
|
2-1 (X-1) | pos. | left (close to beam)
|
2-16 (X-16) | pos. | right (far from beam)
|
|
11
|
Fri Jun 7 14:39:36 2019 |
Jan | Detectors | Pt100 installation & readout | |
The new detector holder incorporates a Pt100 temperature sensor, which is UHV compatible. The Pt-resistor is read out via 4 wires. These wires are integrated into the D-SUB connector of the detector. The new wires use the pins as shown in the attached picture
"det_connector.png".
Additionally, a new cable for air-sided connection to the feedthrough is made. This one has an additional outgoing branch for the 4-wire Pt-100 readout, which can be connected to the readout device.
The readout device is an Omega DP32Pt, which provides pre-calibrated conversion to temperature values for many sensor types.
https://www.omega.de/temperature/pdf/DPPT_SERIES.pdf
https://assets.omega.com/manuals/M5460_DE.pdf
https://data2.manualslib.com/pdf6/133/13210/1320926-omega/cn32pt.pdf?0f771b894ebb783ac172a013ea140d1d |
16
|
Mon Jul 8 14:57:07 2019 |
Yuanming Xing | Detectors | The measurement of the tilting angle | |
As shown in the figure, the detector is tilted by a certain angle which is about 45 degree.
The tilted angle is defined as angle B.
We measured angle A using the vertical laser line (red) and papers with a straight line edge. So we can marked
the line denoted by the laser line when the paper is put on the holder.
In the beginning, the angle A is measured as 43.3±0.5 degree. So angle B= 46.7±0.5 degree
After the adjustment of the detector (to make it in the center of the chamber), the angle A is measured as
43.1±0.5 degree with another paper. So angle B= 46.9±0.5 degree. |
21
|
Thu Aug 29 10:02:22 2019 |
Jan | Detectors | bakeout at ESR setup | |
The bakeout for our detector setup has started on the evening of 27.08.2019
We have a temperature sensor in the vacuum next to the detector.
The goal is to maximize bakeout temperature, while not going above 125°C at the detector/sensor.
Here is a daily protocol of temperatures and vacuum pressure
T_12 is the set value of the 1st and 2nd controller device
T_34 is the set value of the 3rd and 4th controller device
T_56 is the set value of the 5th and 6th controller device
T_sens is the temperature measured by the sensor close to the detector
day date P_setup T_sens T_12 T_34 T_56 comment
1 tue 28.08. 1e-6 mbar ~100° ~120° ~120° ~120° carefull start
2 wed 29.08. 3e-7 mbar ~121° ~180° ~150° ~150° T_sens reached ~126° during NEG-pump conditioning
3 thu 30.08. 6e-7 mbar ~124° ~185 ~150° ~175° readjusted T_56, outgassing a bit increased
7 mon 02.09. 5e-9 mbar ~80° during cooldown
9 wed 04.09. 2e-10mbar ~30° after cooldown, NexTorr Pump active |
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. |
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. |
30
|
Thu Dec 5 10:57:57 2019 |
Jan, Laszlo | Detectors | setting up the DSSD with beam | |
This is a brief how-to about getting the DSSSD set up with stored beam and target in the ESR.
The main goals
1. adjust timing signals to TDC-range
2. adjust energy signals to ADC-range
3. optimize energy resolution
The signal chain is the following:
det [32ch.] > preamp [2x16ch] > 2x MSCF shapers [16ch] |
32
|
Tue Feb 11 13:20:01 2020 |
Jan | Detectors | BaF2 - HV settings | |
with these HV values the 6 channels are roughly gain matched, such that the 7.83 MeV Po-decay is around channel 5000. |
36
|
Fri Feb 21 11:29:59 2020 |
Jan | Detectors | det. distances at target chamber | |
This is the lookup table for the distance of each x-ray detector to the target.
See attched foto for explanation.
Detector | A (dA) [mm] | B (dB) [mm] | C (dC) [mm] | calculate | result [mm]
|
35° | 136.0 (1.0) | 20.0 (0.2) | 450.0 (0.5) | C + B - A | 334.0 (?)
|
90° | 76.0 (0.5) | 20.0 (0.2) | 447.0/2 = 223.5 (1.0) | C + B - A | 167.5 (?)
|
145° | 165.0 (1.0) | 20.0 (0.2) | 450.0 (0.5) | C + B - A | 305.0 (?)
|
Errors are estimated after measurement, final errorbars have to be double checked! |
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. |
38
|
Tue Mar 10 09:41:26 2020 |
Jan | Detectors | x-ray background from BaF | |
The BaF2 detectors planned to be installed at the target induce an additional background in the x-ray detectors sitting below inside the target chamber.
We made test measurements with an x-ray detector for estimating the background in the region of interest for our K-REC measurements (35 to 50 keV).
For the interval [35-50 keV]:
Normal background level: 0.065 (s*keV)^-1
BaF2 in 5cm distance: 0.078 (s*keV)^-1
This is an increase by about 22%
Assuming an increase by 100% induced by 6 BaF2 in the vincinity of the Ge-detectors this seems acceptable.
However additional BaF-induced peaks are also visible at ~30 keV and ~60 keV. While these are not in the region of interest for the K-REC, we need to be aware of them!
spectra are available on the Frankfurt exp-astro Server at /home/glorius/e127/ |
47
|
Sun Mar 15 17:12:40 2020 |
Laszlo, Jan | Detectors | new Ortec spec amps | |
We are now using new SpecAmps for the x-ray detectors from ORTEC, they deliver much improved resolution but have other strange effects as discribed in the next entry. |
88
|
Fri Mar 20 22:26:42 2020 |
Jan | Detectors | BaF2 deactivated | |
BaF2 detectors are deactivated nor for the following runs. |
129
|
Sat Mar 21 13:44:16 2020 |
Pierre-Michel | Detectors | Recoil detector | |
We turn on Recoil detector, to use it as a monitor for target overlap.
MCP front -2500 V for highest signal rate.
(Used to be -2250 V during previous beam time.)
DAQ triggered with 1 kHz clock in 2nd trigger input.
(2nd trigger used to be x-rays in previous beam time.)
The picture shows the increase of the Recoil rate when increasing the voltage from 2250 V to 2500 V in steps of 50 V. The last shot was taken without beam, so just target on. |
152
|
Sat Mar 21 23:12:38 2020 |
Jan | Detectors | removed BaF detectors | |
After run 67 and before run 68, the BaF detectors have been removed in order to reduce the Compton background in the x-ray detectors. |
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 |
284
|
Fri Oct 23 12:58:12 2020 |
Jan | Detectors | Test of 2nd DSSSD (gen2) | 2021 |
This is the documentation of the source tests with the 2nd micron DSSSD of 2nd generation (label 3288-17, thickness 529um)
The detector is put into vacuum (~5e-6 mbar) in our test chamber. The source is positioned a few cm above (see fotos).
The Bayard-Alpert Sensor in the chamber has to be deactivated, otherwise the light emission will increase the noise on the DSSSD strongly and reduce its performance.
Additionally the current and voltage from the CAEN HV is monitored with the vulom scalers: ch.13(Icool) = current; ch.14(Ucool) = voltage.
Source: mixes alpha [239Pu, 241Am, 244Cm]
File directory: lxg1275:/data.local3/test_data_2020/
QuickTest files: si2_test_mixed_source[X].root
lmd files: Si2_run[XXX].lmd
DAQ Settings:
MADC gate : 0 delay, 5000ns width
MSCF shaping: 2 us
trlo config : e127.trlo (trigger=1/tpat=1 for Si, trigger=11 for vulom_scaler)
LMD runs:
-----------------------------
Si2_run001.lmd
Start: Fri 23.10.2020 16:19
Stop: Mon 26.10.2020 8:36
File-Size: 20GB
Events: ~53M
comment:
source roughly centered
CAEN HV scalers not connected
-----------------------------
Si2_run002.lmd
Start: Tue 27.10.2020 16:01
Stop: Wed 28.10.2020 13:26
File-Size: 12GB
Events: ~32M
comment:
source in one corner (x1, y1, see foto)
scalers should be connected now
current monitor range set to LOW
@start det_current=140nA det_voltage=90V
@end det_current=143nA det_voltage=90V
-----------------------------
Si2_run003.lmd
Start: Wed 28.10.2020 13:30
Stop: Wed 28.10.2020 13:31
File-Size:
Events:
comment:
ramping of det. voltage for scaler/U-F-Converter test
source in one corner (see foto)
scalers should be connected now
current monitor range set to LOW
@start det_current=140nA det_voltage=90V
-----------------------------
Si2_run004.lmd
Start: Tue 24.11.2020 12:50
Stop: Tue 24.11.2020
File-Size:
Events:
comment:
source in one corner (x16, y16, see foto)
@start det_current=138nA det_voltage=90V
@end det_current=nA det_voltage=90V
-----------------------------
Si2_run005.lmd
Start: Tue 24.11.2020 14:57
Stop: Tue 24.11.2020 15:11
File-Size:
Events:
comment:
source in one corner (x1, y16, see foto)
@start det_current=144nA det_voltage=90V
@end det_current=nA det_voltage=90V
-----------------------------
Si2_run006.lmd
Start: Tue 24.11.2020 15:24
Stop: Tue 24.11.2020
File-Size:
Events:
comment:
source in one corner (x1, y16, see foto)
Si_X & Si_Y cabling to MADC_0 and TDC_0 exchanged to get right order of channels/orientation
@start det_current=144nA det_voltage=90V
@end det_current=nA det_voltage=90V |
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. |