Low Temperature Facility (LTF) Instrument
Instrument Scientist:
Chris Baines <chris.baines@psi.ch>
Complete list of files pertaining to the
operation of LTF
General Specifications
- Location:
area piM3.3
- Positive muons, momentum 5-30MeV/c (Standard: 28MeV/c)
- Polarization >95%
- Direction of spin ~ 0-50deg with respect to muon momentum
- Positron Detectors: 4
- Main Magnetic Field: 0 - 2.8T (3.0T on request) parallel to the beam
- Auxiliary Field: 0-10mT perpendicular to the beam
- Temperature Range: 11.3mK -10K
Note :
Earth-field compensation is usually better than 0.001mT for all directions.
Some variation (±0.002mT) can occur depending on the position
of the 60-ton crane in the hall. Stray field from Quadrapole Focus Magnets
QSL302/QSE304 at the sample position (+9mG)
Detector Arrangement
The detector arrangement consists of a single Muon (M) Trigger detector
and four positrons detectors.
M
| Backward (left .OR. right) | Forward (left .OR. right) | Left | Right
Sample Environment
Samples: Samples must be of a size (<12.8 mm diameter but can be
up to 16.5mm long and 3.5mm thick) and need only be sufficient to stop
surface muons ~125 mg/cm².
Details of the sample-holder are available
on request or
here.
Cryostat Operation
Operational Modes (Temperature Ranges)
Temperature Measurement & Control
Electronics / Data Aquisition
Data Format and Storage
The users are responsible to store in a safe place their own data.
Every week a backup of the data is performed in the PSI Archive system and
the specific muSR ftp-server (see here
for more information).
You are strongly adviced to retrieve your data ("bin"-format) using our
new ftp-server.
Logic
The new TDC electronics is characterized by a logic performed
exclusively at the software level. A manual is available in
HTML fomat or in
PDF format.
Computers
The area is equipped with a Experiment Console (running
Scientific Linux) pc9627. The µSR data acquisition system hardware consists of this console
and a Linux back-end server (psw406n) located in the computing building (Hauptgebäude).
This back-end is connected to a PC controlling the VME TDC electronics (or to a front-end PC running Windows-XP and controlling
the PTA ORTEC 9308 Unit).
A number of different devices (temperature controlers, magnetic field
power supplies, etc...) are used for the slow control of the experiment.
These devices are mainly controlled via GPIB (IEEE-488) bus or RS-232
serial line.
- GPIB :
The GPIB devices are controlled through a Agilent LAN/GPIB Gateways (E2050A
and the newest E5810A).
- RS-232 :
The RS-232 devices are controlled through either a Agilent LAN/GPIB Gateways
(E5810A)
which supports one RS-232 line, or a Lantronix ETS8PS
8-channel RS232 terminal server
The acquisition software
deltat is based entirely on the DAQ software package
MIDAS.
A Linux Workstation (pc8578) is also available and can be used through
a usual AFS account or a local account (ask the instrument scientist for
information). From this machine, one can connect also to the Linux
cluster.
The secondary
beam-line control system controlling all beam-line elements (magnets,
slit systems, separator etc.) between the target station and the experiment
consists of a CAMAC crate containing the interfaces and modules needed for
the beam line, a server PC (connected via RS232 to the CAMAC crate) and an
area PC (in the GPS control room). The server and area PC's are connected via Ethernet.
Area PC: Intel processor running under Windows XP.
Printers
Information about how to print at PSI is available
here.
The printer located near the LTF cabin has the name: weha_eg_1
Another printer located in the blue cabin near the piE5 area has the name:
weha_e5_2
This latter printer is also equipped with a copying machine.
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