 Fri Feb 23 13:15:05 2018, Thomas Chillery, Raffaele Buompane, David Rapagnani, Setup - Beam Tuning and Prepare Chamber for Measurement at 3.45MeV 7Li - Night of 22nd
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Checking SRIM 3.5 MeV 7Li is stopped in 9.06um mylar or 10.09 um CH2.
After the long run at 3.0MeV on 22/02/2018 we decided to put the 12um mylar back in front of the S2 and start tuning the beam for 3.45MeV 7Li.
We also decided to tune the beam to a higher current of ~ 100pA to try and improve the detection rates. |
Thu Feb 22 18:04:12 2018, Thomas Chillery, Raffaele Buompane, David Rapagnani, Lucio Gialanella, Measurement - 3.0MeV 7Li on CH2 Target VII 
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Yesterday (21st) night we saw this low channel, high rate (1500Hz) noise on the diode spectrum - see eLog entry #15.
This morning the S2 bias was ramped to -130.3V, leak I = 1.43uA. Diode bias ramped to -70.0V, leak I = 0.01uA.
Starting the DAQ with no beam, the trigger rate is ~250 Hz, with most triggers coming from the diode. Inspecting with the oscilloscope we find |
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Thu Feb 22 14:55:09 2018, Thomas Chillery, ADC6 Settings
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| DAQ Settings for ADC6 settings attached. ADC 6 has been used for the pin diode during the week starting 19/02/2018 |
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Thu Feb 22 10:40:49 2018, Thomas Chillery, Raffaele Buompane, David Rapagnani, Lucio Gialanella, Measurement / Test - 3.0MeV 7Li on CH2 Target VII
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On 21/02/2018 after beam tuning and pumping down at 18:07 the pressures read Up = 1.2e-5mBar, Down = 3.2e-5mBar. We were happy to power the detectors
and try to observe spectra from beam in both the S2 and pin diode.
Whilst waiting for the turbos to spin up the Pin diode was daisy chained with the +ve pulser, +15V, and -15V preamp power cables used with EDI |
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Thu Feb 22 07:58:48 2018, Thomas Chillery, Tom Davinson, Raffaele Buompane, David Rapagnani, Lucio Gialanella, Setup - Beam Tuning and Prepare Chamber for Measurement at 3.0MeV 7Li
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On 21/02/2018 we reattempted the beam tuning. We expected this to be easier now the rogue mylar is removed from the beamline.
At 8:30 we started the roughing pumps. At 8:37 the turbos were switched on. By 8:55 the preassures read: Up = 1.6e-5, and Down = 4.3e-5
mBar. |
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Wed Feb 21 10:46:22 2018, Thomas Chillery, Tom Davinson, Raffaele Buompane, David Rapagnani, Setup - Pulser Settings and 20/02/2018 Pulser Walkthrough
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The PB-5 Pulse Generator settings are as follows:
Fall Time = 100us
Rate = 2.00Hz |
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Tue Feb 20 17:03:08 2018, Thomas Chillery, Tom Davinson, Raffaele Buompane, David Rapagnani, Setup - Beam Tuning
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The pumps were left on overnight, in the morning at 8:25 the pressure reads:
Up = 1.5e-5 mBar and Down = 4.0e-5 mBar.
We made a first attempt at collecting an alpha spectrum for the far S2 detector using ADC 2 and ADC 3. However ADC 3 appeared to be acting as |
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Tue Feb 20 16:57:49 2018, Thomas Chillery, Screenshots - ADC 2 and ADC 4 settings, and example pulser walkthrough 11x
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Tue Feb 20 09:19:19 2018, Thomas Chillery, Tom Davinson, Raffaele Buompane, David Rapagnani, Setup - Testing Chamber Vacuum and Mounting Detectors and Alpha Source
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(Note: Tom Davinson is now in CIRCE until the 21st)
On 19/02/2018 we performed the following:
This morning we gave CIRCE technician Antonio slanted spacer boxes (for mounting preamps) and also the Al box (used for target ladder) for minor |
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Sat Feb 17 13:00:51 2018, Thomas Chillery, Test - S2 Detector Bias
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This morning whilst I was setting up the ribbon cabling (see eLog entry #8) I was considering collecting a voltage bias vs leakage current curve for
one/two of the S2 detectors, depending on time available.
This would involve using the central section of the chamber and the straight spacer box to mount the preamp on top of the lid. |
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Sat Feb 17 12:35:25 2018, Thomas Chillery, Setup - Electronic Cabling
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Between 9:00 to 12:30 this morning Filipo was working on the weekend 14C measurements, allowing me to work in the lab during this period.
I unpacked four MALU 4532 Lecroy Logic Modules (sent to CIRCE two weeks ago). Three of these modules were installed into the 1434A CAMAC crate,
which already had one module installed from the July 2017 shift. One module remains out of the crate as a spare. |
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Fri Feb 16 18:28:42 2018, Thomas Chillery, David Rapagnani, Setup - Testing Chamber Vacuum
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By 16:40 I mounted all three chamber lids.
The central chamber lid includes the diode detector mount, the iris, a vacuum feedthrough, and an actuator with no hook.
The downstream chamber lid includes a vacuum feedthrough and an actuator with no hook. |
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Fri Feb 16 18:21:17 2018, Thomas Chillery, Iris arm problems
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After lunch we were still having problems with the aperture hook, see first attached image highlighting the arm is located in close proximity (but not
touching) the vacuum feedthrough and ribbon cable.
Meanwhile in Edinburgh Peter Black designed and built an additional component of the hook to assist in connecting it between the actuator and |
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Fri Feb 16 18:10:34 2018, Thomas Chillery, David Rapagnani, Setup - Electronics Rack and Aperture Iris
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This morning we moved the electronics rack to within ~2.5m of the target chamber, leaving room for the ribbons cables of ~5m length which connect the
preamps to the amplifiers in the rack.
Then I continued in attempts to solve the iris arm problem, see eLog entry #3. |
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Thu Feb 15 20:45:27 2018, Thomas Chillery, Planning - Target Chamber CAD diagram
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| Find attached the latest CAD diagram of the Target Chamber, drawn by Peter Black |
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Thu Feb 15 17:45:07 2018, Thomas Chillery, Raffaele Buompane, Setup - Problem: Connecting the actuator arm to the iris aperture arm
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After lunch we attempted to connect the actuator arms to the iris arm used to change the iris diameter. We need two iris diameters: fully open for experiment
measurements and a 5mm diameter for beam focusing
To do this the original design uses a cuboid with two rods, one rod is connected to the actuator arm, and the other rod is connected to the iris |
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Thu Feb 15 17:34:28 2018, Thomas Chillery, Raffaele Buompane, Setup - Mounting Target Chamber Sections
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This morning both myself and Raffaele mounted the beamline section of the target chamber.
We also mounted the turbo located immediately downstream from the target chamber, see attached IMG_2621.jpg image - the beam will enter from
the right of the image |
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Tue Aug 1 12:26:13 2017, Thomas Chillery, 10th - 22nd July 2017 Summary Report
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Attached is a report summarising work performed on the electronics and target chamber in CIRCE from the 10th to the 22nd July 2017.
Outstanding problems have also been listed. |