1284 lines
34 KiB
Markdown
1284 lines
34 KiB
Markdown
% User Manual
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for the
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Neutron Reflectometer Amor
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% Jochen Stahn
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% 2024-06-06
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---
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# Users' guide to NICOS
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## open NICOS
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- *normal* users should be logged on as `amorlnsg` on the instrument control computer `amor.psi.ch`.
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That is the one under the desk in the control cabin.
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> computer: `amor.psi.ch`
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> username: `amorlnsg`
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> password: ask beamline scientist
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- create a local subdirectory for the actual campagne:
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1. Open a terminal and enter your name. Probably create a new directory with your name.
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You will end up in this directory.
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1. Create a sub-directory: `mkdir <year>-<month>` (or the like).
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1. `cd <year>-<month>`
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- open the NICOS gui by typing
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> `nicos-gui`
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in a terminal window as user `amorlnsg`.
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The gui will start up. Probably you will have to connect to the NICOS program:
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> in the upper right corner type the wheel and select *connect*
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> user: `user`
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> password: ask beamline scientist
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## identify yourself
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Upon starting a measurement campagne, you have to enter the following
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information:
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- proposal ID
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- title
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- user name(s)
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- affiliation?
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The information is used to create a repository for your data and is
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also stored in the meta data section of all your files.
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## brief intro for NICOS commands
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### check and change device parameters
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- everything is a *device*
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- each device has a *name*, in most cases a 2 to 3 letter abbreviation
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e.g. `som` for the sample tilt (*s*ample *om*ega)
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- get the **description** for a device:
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> `<device>`
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- get the **present value** (position, angle, ...):
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> `<device>()`
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- get all the paramters (position, unit, limits, ...):
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> ???
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- **move** to a new value (and wait until the command is executed):
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> `maw(<device>, <value> [, <device2>, <value2> ...])`
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All these actions are also realised in the gui: klick on the device name in the
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right pannel. A pop-up window opens with all the options available.
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### counting and scanning
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### batch file creation and execution
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## define set-up
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...
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### devices
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`read(<device>)`
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: reads the value of a *device*
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`maw(<device>, <value> [, <device2>, <value2> ...])`
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: (move and wait) moves a *device* to *value*
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### left over and does not belong here
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The sample must be positioned with the center of its surface at the
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focal point. At the same time it should be in the center of rotation of
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the $\omega$ stage. For this reason there are 2 vertical **translation**s which are
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close to parallel:
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`soz`
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: = *S*ample *O*mega stage *Z* position
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: Lift of the $\omega$ stage so that its center is in the FP.
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`stz`
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: = *S*ample *T*ranslation *Z* direction
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: Lift of the sample on the $\omega$ stage to bring it to the
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center of rotation.
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: *This stage is not available at the moment!*
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And finally the sample has to be **tilt**ed by using the $\omega$ and $\chi$ stages.
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`mu`
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: Tilt of the sample relative to the horizon.
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: On amor $\mu$ is used to define and probably to describe the sample
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orientation relative to the lab horizon. Since the beam might be convergent
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on the sample surface it is not the neutron's angle of incidence!
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See also *[coordinate system(s) and nomenclature]*.
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`nu`
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: Rotation of the detector center around the sample position
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relative to the lab horizon. This is a combined movement of
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detector lift, tilt, (*x* translation) and also affects
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all other devices behind the sample.
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Diaphragms
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`d<n><m>`
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: = *d*iaphragm number *n*, blade or position *m*
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: $n \in \{\mathrm v, 1..4\}$ for $v$irtual source and *n*umber of diaphragm.
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: $m \in \{\mathrm{t, b, l, r, h, v, z}\}$ for *t*op, *b*ottem, *l*eft, *r*ight,
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*h*orizontal, *v*ertical and *z*-position.
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: not all options rea available for all devices.
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| name | description | *m* | range or values / mm |
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| :--- | :--- | :--- | :---: |
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| `dvv` | virtual source vertical | | 0.5 1 2 3 4 6 8 10 |
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| `dvh` | virtual source horizontal | | 2 5 10 12 15 20 25 30 |
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| `dmf` | middle focus | | slot 1 .. 5 |
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| `d1<m>` | behind Selene guide | `t b l r` | -40 .. +40 |
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| `d2<m>` | before sample | `t b l r` | -40 .. +40 |
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| `d2Z` | '' lift | | -100 .. +100 |
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| `d3<m>` | behind sample | `t b l r` | -40 .. +40 |
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| `d3Z` | '' lift | | -100 .. +100 |
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| `d4<m>` | before detector | `h v` | +1 .. +140 |
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## perform measurement
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The $q_z$ range of one measurement is defined by the wavelength
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range $\lambda \in [3.5, 12.5]$ \AA\ and the spread of the angles
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of incidence $\alpha_i$.
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For specular reflecivity, $\alpha_i$ is deduced from the position (i.e. angle)
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of the detector and the position on the detector where a neutron is detected.
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`count(<mode>=<preset>)`
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: count with *mode*
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- `t` = time for *preset* seconds
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- `m` = monitor for *preset* monitor counts
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`scan(<device>, <start>, <step>, <np>, <mode>=<preset>)`
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: scan the *device* from *start* with *np* steps of width *step* with the
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counting time defined by *mode* / *preset*
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`run(<scriptname>)`
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: *run* the script *scriptname*, who's path is either relative to
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`Exp.scriptpath` or which has an absolute path. The script language is
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python.
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# How to perform a measurement
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It is assumed here that NICOS is running, the basic data are provided and the
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general set-up is realised.
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## identify sample
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Enter a name and a description of the sample. This information will
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end up in the meta data section.
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NewSample(<sample name>)
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It is also advised to give a short sample description in orso model format:
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Sample.orsomodel='<model>'
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e.g.
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Sample.orsomodel='air | 20 ( Ni 5 | Ti 7 ) | SiO2'
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## align sample
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There are 2 sets of (virtual) devices: the ones for aligning the smaple and the ones
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to select a certain $q$ range or instrument set-up.
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The **sample alinment devices** are:
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`mud`
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: for *pitch correction*:
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: To compensate the misalignment of the sample surface with respect to the
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: sample table surface along the beam.
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`sch`
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: for *roll correction*:
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: To compensate the misalignment of the sample surface with respect to the
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: sample table surface normal the beam.
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`sz`
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: for *height adjustment*:
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: To bring the sample surface to the center of rotation = focal point
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: of the neutron beam.
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It is not necessary - nor is it allowed - to rerdefine any device's zero position!
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### height alignment
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In case the sample surface or a mark outside the sample enviromnet indicating
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its position are visible, one can use the **surveyor's optical level** mounted
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outside the Amor area at the wall next to the experimental cabin.
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This ensures that the sample is in the beam with a vertical offset of a few tenths
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of a mm.
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If possible, an **absorber** at a defined distance above (or below) the sample surface
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can be used: Scanning the sample though the direct beam allows for detecting this absorber
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and moving to the right position.
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Using the full divergence and a large virtual source allows for pitch-misalignments
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of up to $1^\circ$ and height-offsets of 5 mm to still generate a signal on the detector
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for a reflected beam. A good choice for `mu` for searching some signal in this case is
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$0.8^\circ$.
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### pitch
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If one of the schemes 'simple' or '???' is used, the detector is positioned in a way
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that the refelcted beam footprint is centered. This means that the lower edge of
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the footprint - which is much easire to detect then the upper edge - is half the divergence
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below the detector center. The center is at channel number $z = 224$.
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If the full divergenc of $1.5^\circ$ is used, the lower footprint boundary is
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at channel number $z = 384$.
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### roll
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Once *height* and *pitch* are (roughly) aligned, the *roll* can be corrected by looking at the
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$I(y, \theta)$ detector image of the reflected beam. The lower boundary of the
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footprint should be exactly horizontal.
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The *roll* is independent of *pitch* and *height*. An iterative alignment process is thus not
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necessary.
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An accuracy of about $0.1^\circ$ is sufficient.
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### fine alignment
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The beam cross section at the focal plane is mimimum for the settings
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> `div` = $0.05^\circ$
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> `kad` = $0.70^\circ$
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> `dmf` = 1
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I.e. *height* and *pitch* alignment with these settings at a moderate $q$ should
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give the best results. The iterative procedure is similar to 'conventional'
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reflectometers:
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> - scan of `sz` to find the *height* maximum
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> - adjust `mud` so that the beam footprint if centered at detector
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> channel $z = 224$
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## measurement: ranges, angles and duration
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## reduce data
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The *raw* data at amor are stored in the nexus hdf format. Besides some meta data
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bout the experiment and the set-up, it contains the measurement data in form of an event.
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I.e. each neutron has one entry with the time and location (better: voxel-ID) of detection.
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There is the python program code **eos** to reduce the event stream to something like a
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Intensity vs. wavelength and angle map. This process includes a variety of corrections
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(instrument geometry, chopper properties, filtering in wavelength and footprint size, gravity,
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etc. If available, a reference measurement (characterising the incident beam, the detector
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efficiency and absorption of the sample environment) can be used to create a
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$R(\lambda, \theta)$ map for specular reflectometry, ....
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and finally an $R(q_z)$ curve.
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The output format follows the *orso* rules.
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### location of the raw data files:
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If not specified differently, **eos* looks for the raw data files in the following directories:
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`./`, `./raw/`, `../raw`, `../../raw`, `/home/amor/data/<year>/<proposalname>`
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The present approach is to create a subdirectory for the present experiment
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/home/amorlnsg/<user>/<date_description>
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and in there a link to the raw files (if it does not already exist)
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cd /home/amor/data/<year>/<proposalname>
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ln -s /home/amor/data/<year>/<proposalname> raw
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### activate the virtual environment for eos
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in the terminal in which the data reduction is to be performed type:
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```bash
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source ~/eos/venv/bin/activate.csh
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```
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### run eos
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**eos** is a command line script. This means that all necessary information is
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provided as arguments after the program call on the same line.
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At least a file (measurement) number and the name of the output file have to be
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provided. This then looks like
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```bash
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python ~/eos/eos.py -f <number> -o <name>
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```
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All 'missing' information is guessed or collected by eos, where most default values
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are extracted form the raw data file (e.g. beam divergence, instrument settings,
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sample and detector angles). Almost all relevant values can be overwritten by
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an command line option - in most cases this is not recommended!
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Useful arguments for data reduction are:
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data file(s):
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`-f <value>`
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: number(s) of the raw data files
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: the general format is
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: `<number0>-<number1>:<increment0>[,<number2>-<number3>:<increment2>..]`
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: !!!
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`-n <value>`
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: number of the reference file for normalisation
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`-Y`
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: year of the data collection (in order to create the correct raw file name.
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: The default is the actual year.
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filtering / region of interest:
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`-l <low> <high>`
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: wavelength range in angstroms
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`-t <low> <high>`
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: theta range
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`-y <low> <high>`
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: horizontal pixel range on the detector
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`-q <low> <high>`
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: $q_z$ range
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correct angle:
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`-m`
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: offset to the `mu` stored in the data file
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`-mu`
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: overwrite the data file entry
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scaling:
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`-S <low> <high>`
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: scale the (weighted) average in the given $q_z$ range to 1
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`-s <value>`
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: multiply *reflectivity* by *value*; executed after `-S`
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formats:
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`-of Rqz | Rlt | ort | orb`
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: Defines what is written to the file:
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: `Rqz`: $R(q_z)$,
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: `Rlt`: $R(\lambda, \theta)$ and much more
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: and in which format:
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: `ort`: ASCII file
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: `orb`: nexus conform binary file
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`-h`
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: get help on eos and a description of all arguments.
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# Instrument description
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Amor is a neutron reflectometer with a beam focused to the sample position.
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## Parameters and options
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- wavelength range
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- angular range
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- q range
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- polarisation efficiency
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- angle of incidence on liquid surfaces
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- sample environment
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- 1 T electomagnet (with closed cycle refrigerator)
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- 7 T cryomagnet, horizontal field direction
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- furnaces
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- LB trough
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- sheer cell
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- potentiostate / galvanostate
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## From physical source to virtual source
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The *real neutron source* is the spallation target at SINQ. The fast
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neutrons created there by proton capture in lead nuclei are moderated
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to room temperature using D~2~O, and further down to cold
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neutrons by a liquid H~2~ moderator. This is often referred to as
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*cold source*.
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Some of these cold neutrons are guided by a 4.5 m long converging
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neutron guide (with m = 2.5 coating) to the *virtual source* (VS) position,
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just outside the shileding monilith at 6 m from the surface of the
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cold moderator.
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virtual source
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: _
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: 2 Boron-Aluminium wheels with horizontal
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and vertical slits of various sizes, respectively.
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The opening (luminous field diaphragm) is centered at the guide
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focal point.
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Table: Vertical and horizontal slit widths of the virtual source diaphragm.
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| opening | vertical | horizontal |
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| ---: | ---: | ---: |
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| | / mm | / mm |
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| 1 | 0.5 | 2.0 |
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| 2 | 1.0 | 5.0 |
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| 3 | 2.0 | 10.0 |
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| 4 | 3.0 | 12.0 |
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| 5 | 4.0 | 15.0 |
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| 6 | 6.0 | 20.0 |
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| 7 | 8.0 | 25.0 |
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| 8 | 10.0 | 30.0 |
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## Selene guide
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The divergent neutron beam emerging from the *virtual source* slits is
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collected and focussed to a point (the *mdiddle focus*, MF)
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some 15 m away from the VS by a set of
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two elliptically bent mirrors (i.e. a Montel optics), where one reflects horizontally towards
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the Aare, and the other vertically upwards.
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The image of the VS at the MF is distorted due to come aberatin. To correct for this
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to first order, a second Montel optics follows which reflects towards Berg and downwards.
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This results in an image of the VS at the final focal point, some 30 m behind the VS.
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This image is distorted spatialy due to imperfections of the Montel optics (surface and alignement)
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and it is inhomogeneous in intensity due to an only partially corrected divergence distribution and
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due to losses during reflection.
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This arrangement of two Montel optics we called **Selene guide**.
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The Selene guide is made up of about 500 mm long L-shaped elemets. These are individually
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tiltable in vertical direction (*pitch* movement). 6 of these elements are bundeled on a
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support beam which rests on two vertically movable sockets. 3 beams form one Montel optics.
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All these movements are highly delicat because they might lead to collissions and thus
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demage at places that are not accessable for years - if ever again. Thus no user is
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allowd to run these.
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The housings of each Montel optics plus the ones of some beam shaping elements and of
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one chopper disk each form a continuous vacuum vessel.
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The Montel optics are each some 9 m long and located symmetrically between the adjunct focal
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points. This means there are gaps between VS and guide entry and the guide exit to FP of
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3 m, and of 6 m between the Montel optics. These gaps are used for conditioning the
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neutron beam.
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### characteristic measures
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- $a = 7'421\,\mathrm{mm}$
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- $b = 129.50\,\mathrm{mm}$
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- $c = \sqrt{a^2 - b^2} = 7'420\,\mathrm{mm}$
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- $4c = 29'680\,\mathrm{mm}$
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- $\Delta \alpha = \arctan \frac{b}{a} \sqrt{\frac{1+\xi}{1-\xi}}
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- \arctan \frac{b}{a} \sqrt{\frac{1-\xi}{1+\xi}}$
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$\approx\, 1.5\, b/a \,\approx\, 1.5^\circ$ for $\xi = 0.6$
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## Optics in the bunker
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The gap between VS and Montel optics is bridged by an evacuated flight tube.
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The large central gap hoists:
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polariser / frame overlap filter
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: \hfill MF - 2700
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: The polariser consists of Fe/Si supermirror coated Si blades which are bent in
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the shape of a logarithmic spiral with the MF as the spiral pole. To enhance
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the polarisation efficiency, 2 of these sheets are mounted with a distance of a few
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cm. The total arrangement is some 2.1 m long.
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: The frame overlap filter (FOF) has a similar design, but only one sheet, coated on the
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outside (towards the source) with Ni.
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: Both are monted one baove the other and switching means a vertical translation of the
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assembly.
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first chopper disk
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: (master) \hfill MF - 500
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: The chopper disk has 2 openings of 13.5^o^, each, and rotates with a speed of
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1000 rpm creating pulses ever 33.33 s.
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: The beam shaping properties are discussed below in context with the second chopper disk.
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main shutter
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: \hfill MF - 300
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beam monitor
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: \hfill MF - 250
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: The monitor is a fission chamber with sensitivity 10^-?^.
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neutron camera
|
|
|
|
: \hfill MF
|
|
: For alignment purposes. By default not in the beam.
|
|
|
|
middle focus aperture
|
|
|
|
: \hfill MF
|
|
: Wheel with 5 freely configurable slots.
|
|
Presently unused.
|
|
|
|
second chopper disk
|
|
|
|
: (slave) \hfill MF + 500
|
|
: Geometrically identical to the first chopper disk, but rotating
|
|
in the opposite sense with a phase offset of -13.5^o^.
|
|
This way they form a *blind double chopper* with a resolution
|
|
$\Delta t/t = \Delta \lambda/\lambda = constant$. [@vanWell]
|
|
The center of this set-up, i.e. MF, is the virtual origin in time and space
|
|
for the time-of-flight encoding of wavelength $\lambda$.
|
|
|
|
|
|
RF spin flipper
|
|
|
|
: _
|
|
|
|
and some shielding elements and flight tubes.
|
|
|
|
These optical elements produce a neutron beam which
|
|
|
|
- is convergent to the FP
|
|
- is restricted to a wavelength range of 3 to 9.5 Aa
|
|
- might be polarised with selectable polarisation
|
|
- has a time focus 15 m before the FP (i.e. the pulse they belong to was
|
|
virtually created 15 m upstream for all divergences due to the
|
|
equal trajectory lengths in an ellipse).
|
|
|
|
## Optical bench
|
|
|
|
Behind the exit of the second Montel optics the following
|
|
components are / will be / might be installed:
|
|
|
|
instrument shutter
|
|
|
|
: _
|
|
|
|
laser system for sample alignment
|
|
|
|
: (to come)
|
|
|
|
diaphragm D1
|
|
|
|
: (to come)
|
|
: for defining vertical and horizontal divergences
|
|
and for changeing the angle of incidence for a reduced beam within the
|
|
full divergence of 1.5 deg.
|
|
: individual movement of $\pm40$ mm of all 4 blades relative to center
|
|
|
|
deflector
|
|
|
|
: (to come, optional)
|
|
: to redirect a restricted beam downwards to
|
|
liquid surfaces
|
|
|
|
diaphragm D2
|
|
|
|
: (to come)
|
|
: to reduce background
|
|
: individual movement of $\pm40$ mm of all 4 blades relative to center
|
|
|
|
sample table
|
|
|
|
: _
|
|
|
|
diaphragm D3
|
|
|
|
: (to come)
|
|
: to reduce background
|
|
: individual movement of $\pm40$ mm of all 4 blades relative to center
|
|
|
|
analyser spin flipper
|
|
|
|
: (future option)
|
|
|
|
analyser
|
|
|
|
: (future option)
|
|
|
|
diaphragm D4
|
|
|
|
: (to come)
|
|
: vertical / horizontal slit with 1 to 160 mm opening, centered
|
|
|
|
detector
|
|
|
|
: _
|
|
: the active region starts 4'000 mm behind the FP and 18'842 mm
|
|
behind the MF in standard position
|
|
: The detector was designed and built by the ESS detector group.
|
|
It is a prototype for the detector for Estia@ESS with a reduced active area
|
|
of $140 \times 160$ mm^2^. The full beam footprint is
|
|
$110 \times 120$ mm^2^.
|
|
|
|
In addition there might be flight tubes and shileding.
|
|
|
|
## Infrastructure
|
|
|
|
### Areas
|
|
|
|
### Media
|
|
|
|
### EDV
|
|
|
|
|
|
#### Amor network
|
|
|
|
By default all LAN sockets in the experimental areas (below the granite
|
|
beam and against the bunker wall on the upper area) and all
|
|
LAN sockets in the cabin below the desk are connected to the Amor
|
|
network.
|
|
|
|
In this network there are also the instrument controll computer
|
|
and computers for the detector, the chopper, ....
|
|
|
|
#### PSI network
|
|
|
|
By default the 2 LAN sockets in the corner opposite the the doors in the
|
|
cabin are connected to the PSI web.
|
|
|
|
!!! WLAN: EDUROM, CORP
|
|
|
|
### PSYS
|
|
|
|
# Experiments
|
|
|
|
## coordinate system(s) and nomenclature
|
|
|
|
The lab coordinate system is ...
|
|
|
|
z
|
|
: vertical direction
|
|
|
|
x
|
|
: horizontal, parallel to the projection of the beam center at the
|
|
sample position on the horizontal plane
|
|
: roghly pointing from *Böttstein* towards *Villigen*
|
|
|
|
y
|
|
: horizontal, forming a right-handed system with x and z
|
|
: roughly pointing from *Berg* towards *Aare*
|
|
|
|
The special situation with an incoming beam on the sample with
|
|
potentially a divergence of up to 1.5^o^ requires a differentiation
|
|
between sample tilt ($\omega$) and angle of incidence ($\alpha_i$).
|
|
In the case of specular reflectivity we define $\theta := \alpha_i =
|
|
\alpha_f$.
|
|
|
|
We define $\omega$ as the tilt angle of the sample with respect
|
|
to the horizon of the instrument. I.e. for liquid surfaces it is
|
|
allways zero!.
|
|
|
|
|
|
*to be checked for consistency:*
|
|
The position of the detector $\delta$ (realised by 2 translations in $x$ and
|
|
$z$ direction), its tilt towards the sample $-\delta$ and the
|
|
detection position of the neutron on / in the detector described by $\Delta\delta$
|
|
result in an angle $\delta + \Delta\delta = \omega + \theta$ relative to the
|
|
instrument horizon. Thus
|
|
$$ \theta = \delta + \Delta\delta - \omega$$
|
|
|
|
|
|
|
|
|
|
## Set-up options
|
|
|
|
### polarisation
|
|
|
|
Amor is (will be) equipped with a spiral-shaped neutron polariser.
|
|
It is located before the first chopper within a vacuum housing in
|
|
the neutron guide bunker.
|
|
|
|
The polariser is mounted on a vertical translation system which
|
|
allows for 3 settings:
|
|
|
|
- **polarised**: the polariser with a frame overlap filter coating
|
|
is in the beam
|
|
- **unpolarised**: the frame overlap filter is in the beam
|
|
- **open**: the neutron beam passes in between polariser and
|
|
frame overlap filter
|
|
|
|
### liquid surfaces
|
|
|
|
(not yet installed)
|
|
|
|
The neutron beam can be inclined downward onto a horizontal (liquid)
|
|
surface by a mirror mounted on the optical bench right after the
|
|
first diaphragm.
|
|
|
|
The limited acceptance of this mirror means that only a small part of
|
|
the beam can be used. I.e. wide-divergence reflectometry is not
|
|
possible in this mode. The srrong off-specular scattering from a
|
|
liquid surface anyhow asks for a low-divergent beam.
|
|
|
|
Within the divergence of the beam before the first diaphragm it is
|
|
possible to scan / vary the angle of incidence on the sample
|
|
without moving it vertically.
|
|
|
|
### beam divergence
|
|
|
|
The *natural* divergence of the beam at the sample position
|
|
in the scattering plane is about 1.5 deg. It can be reduced by
|
|
closing the first slit behind the guide, D1.
|
|
|
|
The independent movement of the blades allows to vary or scan
|
|
the position of the slit opening across the divergent beam.
|
|
I.e. The angle of incidence on the sample can be changed without
|
|
tilting the sample.
|
|
|
|
---
|
|
|
|
# cold start of the instrument
|
|
|
|
Short description of how to start hard- and software after the shut down
|
|
or after a power failure.
|
|
|
|
## electronic racks
|
|
|
|
Starting the **motor control units** (MCU) in rack 1 and the **SPS** in rack 3
|
|
has to be done by the repsective LIN staff. Presently that would be
|
|
Marccel Schild (MCU) and Roman Buerge (SPS).
|
|
|
|
Once the SPS is running, one has to set the gas flows for the detector and
|
|
probably for the flight tube:
|
|
|
|
```
|
|
SPS
|
|
|- main
|
|
|- Detector
|
|
|- gas flow 'Detector counting gas' to 7 sccm
|
|
|- gas flow 'Flight tube Argon' to 10 sccm
|
|
```
|
|
|
|
## chopper
|
|
|
|
Starting the chopper is tricky, instable and time-consuming. Be patient.
|
|
Mind the order of the operations!
|
|
|
|
Situation: *device control unit* DCU (upper box, small display) and supervision
|
|
(lower box with large screen) switched off
|
|
|
|
1. switch on DCU and boot
|
|
key switch to 'PC'
|
|
1. switch on supervision (back side), boot and wait for `AMOR GUI` to start
|
|
1. on the controll screen:
|
|
|
|
1. klick on the top bar of *Chopper 1*
|
|
1. tag *Chopper*: *DCU Command* to `Callibrate`
|
|
*accept-key*
|
|
1. klick on the top bar of *Chopper 2*
|
|
1. tag *Chopper*: *DCU Command* to `Callibrate`
|
|
*accept-key*
|
|
1. wait for both choppers to report *positioning* or *ready*
|
|
on the DCU screen
|
|
1. klick on the top bar of *Chopper 1*
|
|
1. tag *Chopper*: *DCU Command* to `Async Rotation`
|
|
*Speed* to 500 rpm
|
|
*accept-key*
|
|
1. klick on the top bar of *Chopper 2*
|
|
*DCU Command*: `Sync. rotation`
|
|
*Phase*: -17
|
|
*Master*: `Master Chopper 1`
|
|
*Gear Ratio*: `1/1`
|
|
*accept-key*
|
|
1. should be fine now!
|
|
|
|
## amor computer and instrument control
|
|
|
|
The instrument control computer `amor.psi.ch` (`172.28.65.60`, `PC14655`)
|
|
is located in the cabin under the table on the right side.
|
|
|
|
1. switch on and boot
|
|
1. log in as user *amorlnsg* (24lns1)
|
|
1. start and control processes:
|
|
open a terminal window and switch user to *amor*:
|
|
|
|
```
|
|
su - amor
|
|
marche-gui
|
|
```
|
|
|
|
in Marche gui:
|
|
|
|
- klick `amor.psi.ch`
|
|
- start *nicos*
|
|
- start *amorIOC*
|
|
- start *Histogram Memory*
|
|
- start all *Kafka-to-Nexus...* processes
|
|
- start *Automatic File Sync*
|
|
|
|
1. start NICOS:
|
|
|
|
- open a terminal window and enter
|
|
`nicos-gui &`
|
|
- in the NICOS gui klick the tooth wheel
|
|
`Connect to server`
|
|
*User name*: `user`
|
|
*Password*: `24lns1`
|
|
*OK*
|
|
|
|
## detector
|
|
|
|
see section *MBamor*
|
|
|
|
|
|
## data visualisation and reduction
|
|
|
|
as user `amorlnsg@amor.psi.ch` (i.e. when opening a new termminal on the amor computer)
|
|
perform the following steps:
|
|
|
|
```
|
|
source ~/eos/venv/bin/activate.csh
|
|
cd <working directory>
|
|
python ~/eos/events2histogram.py
|
|
display -update 2 e2h.png &
|
|
```
|
|
|
|
Now you can use `events2histogram.py` for fast visualisation and
|
|
`eos.py` for data reduction in THIS terminal window.
|
|
|
|
## sample environment
|
|
|
|
in NICOS gui:
|
|
|
|
```
|
|
|- Setup
|
|
| |- Instrument
|
|
| | |- frappy -> select
|
|
| | |- frappy_main -> select
|
|
| |- Apply
|
|
|
|
|
|- Instrument interaction
|
|
|- output -> type frappy('<device>')
|
|
```
|
|
|
|
e.g. potentiostat:
|
|
`frappy('smamor')`
|
|
generates `frappy-main` with devices `se_smi` and `se_smv`
|
|
|
|
in terminal window:
|
|
|
|
```
|
|
sea
|
|
```
|
|
|
|
---
|
|
|
|
# Marche - daemon control
|
|
|
|
The daemons for NICOS, EPICS, `filewriter` and so on are controlled via
|
|
`Marche`.
|
|
|
|
1. `marche` gui
|
|
|
|
> 1. log in as user `amor@amor.psi.ch`
|
|
> 1. call `marche-gui`
|
|
|
|
1. `marche` script ?
|
|
|
|
|
|
|
|
# the detector **MBamor**
|
|
|
|
## parameters
|
|
|
|
size: 14 blades, each 32 channels high and 64 channels wide
|
|
sample detector distance (to blade tips): 4000 mm
|
|
(distance blade tip to housing front: 33 mm
|
|
inclination of the blades: 5.1 deg
|
|
separation of blades: 10.5 mm or 0.15 deg
|
|
|
|
|
|
## launching of electronics and hardware
|
|
|
|
1. start server **det-efu02** in rack 1
|
|
(a monitor might be needed during booting to enable 'vnc')
|
|
1. switch on **master module** in rack 1
|
|
1. switch on **assistor**s on top of the detector tower
|
|
(probably just reconnect the LV cables)
|
|
check **Master/ring status**: should be 'not configured'
|
|
1. ramp up **HV**
|
|
|
|
| channel | name | U / V | I / $\mu$A |
|
|
| --- | --- | ---: | ---: |
|
|
| 0 | K1 | 1230 | 73 |
|
|
| 1 | R1 | 1050 | 41 |
|
|
| 2 | K2 | 1230 | 73 |
|
|
| 3 | R2 | 1050 | 41 |
|
|
|
|
(start from *off* position, not from *kill*)
|
|
|
|
## start processes on server **det-efu02**
|
|
|
|
|
|
The actions below can either be performed via `ssh` or `vnc`. In the latter case
|
|
(more challenging for the server graphic card) one might have to start the
|
|
**vncserver** first on the det-efu02:
|
|
|
|
> presently, vnc does not work - most likely because of RH8.
|
|
> use `ssh` instead!
|
|
>
|
|
> 1. start `vncserver` (optional, should be launched at booting)
|
|
>
|
|
> ```
|
|
> cd essproj
|
|
> ./startvnc
|
|
> cd
|
|
> ```
|
|
> 1. change graphic settings for vnc
|
|
>
|
|
> ```
|
|
> cd detg_git
|
|
> ./display_vnc
|
|
> cd
|
|
> ```
|
|
> connecting via `vnc`
|
|
>
|
|
> - via web browser from `amor` or `amor-dr`:
|
|
> enter 'vnc://det-efu02:5901' in address bar
|
|
> - via `boxes` on console
|
|
> `vnc://172.28.65.80:5901` mit passwd `essdaq`
|
|
|
|
1. log into `det_efu02`:
|
|
(e.g. from a terminal window on the computer `amor.psi.ch` as user `amor` or `amorlnsg`)
|
|
|
|
```
|
|
ssh essdaq@172.28.65.80
|
|
```
|
|
|
|
(password `essdaq`)
|
|
|
|
1. start **ring controll**`
|
|
|
|
```
|
|
cd slowctrl_rmm
|
|
./run_all.sh
|
|
cd
|
|
```
|
|
|
|
(the `poll` numbers should not exceed 16)
|
|
|
|
the **master/ring status** shown on the master module should be green for rings 0, 1 and 2
|
|
|
|
1. start slow controll pannel
|
|
|
|
```
|
|
./vmmdcs &
|
|
```
|
|
|
|
`VMM3a` opens
|
|
|
|
initialise slow control in `VMM3a` window
|
|
|
|
1. load configuration
|
|
|
|
- *open folder* (lower left region)
|
|
- select 'Amordetector....' and *open*
|
|
- *Load*
|
|
|
|
*FEN00\** shows up
|
|
|
|
1. initialise and start acquisition
|
|
|
|
- *open communication*
|
|
- array on the left should show '4' for all hybrids
|
|
|
|
> if not all hybrids show '4':
|
|
>
|
|
> - *ACQ off*
|
|
> - select *FEN0/1/2*
|
|
> - *Warm init*
|
|
> - *Send*
|
|
> - *ACQ on*
|
|
>
|
|
> escalation:
|
|
>
|
|
> 1. *Hard reset* (lower right corner)
|
|
> 1. power cycle LV (NOT front end assistors)
|
|
|
|
- *send*
|
|
- *ACQ on*
|
|
- array on the left should show '5' for all hybrids
|
|
|
|
|
|
1. start **event formation unit**s
|
|
|
|
```
|
|
cd Desktop
|
|
./runall.bash
|
|
cd
|
|
```
|
|
|
|
## start processes on `amor-dr`
|
|
|
|
### daqlite
|
|
|
|
start `daqlite` for *real*time images of detector output
|
|
|
|
```
|
|
cd Desktop
|
|
./daqlite.bash
|
|
cd
|
|
```
|
|
|
|
## start processes on `amor`
|
|
|
|
### graphana
|
|
|
|
to monitor the efu activity
|
|
|
|
1. on amor:
|
|
|
|
- open Firefox tab
|
|
- enter `https://172.28.65.80:3000` (or bookmark)
|
|
- select 'Freia'
|
|
|
|
2. on `amor`:
|
|
|
|
- open firefox browser
|
|
|
|
address: `vnc://det-efu02:5901`
|
|
passwd: essdaq
|
|
|
|
- open browser
|
|
|
|
select AMORB2
|
|
|
|
|
|
## shut down
|
|
|
|
1. **slow controll**: *ACQ off*
|
|
2. switch off **front end assistor**s
|
|
3. in random order:
|
|
|
|
- close slow controll
|
|
- close daqlite
|
|
- stop **efu** on det-efu02:
|
|
|
|
```
|
|
cd Desktop
|
|
./stopall.bash
|
|
cd
|
|
```
|
|
|
|
4. shut down det-efu02
|
|
(can be powerd off without shutting down)
|
|
|
|
## configuration options
|
|
|
|
### chopper signal
|
|
|
|
The default setting is that the chopper trigger signal is used as a timing signal.
|
|
I.e. without chopper TTL signal, no data acqusition.
|
|
This can be changed on 'det-efu02' in the script `.../run_all.sh` at approximately line
|
|
30:
|
|
toggle the comments on the entries
|
|
`...`
|
|
and
|
|
`...`
|
|
|
|
## maintanance
|
|
|
|
### temperature
|
|
|
|
check every couple of weeks:
|
|
*VMM3a / I2C / measure*
|
|
|
|
### uptime
|
|
|
|
The **VMM**s have a limited life time (approx 5 years). It is thus recommended to
|
|
power them down if not used for more than about a week:
|
|
*VMM3a / ACQ off*
|
|
disconnect LV power cable
|
|
|
|
### trouble shooting
|
|
|
|
- **dark lines
|
|
*VMM3a / ACQ off*
|
|
*VMM3a / FEN\* / Warm init*
|
|
*VMM3a / Send*
|
|
*VMM3a / ACQ on*
|
|
|
|
- **dark area**
|
|
on detector image but all hybrids show '5' (green):
|
|
restart rings:
|
|
`det-efu02> .../run_all.sh`
|
|
|
|
- **no data**
|
|
|
|
- chopper TTL signal might be missing
|
|
- *VMM3a / ... * all on '5' (green):
|
|
restart rings:
|
|
`det-efu02> .../run_all.sh`
|
|
|
|
# trouble shooting
|
|
|
|
## (re)start services
|
|
|
|
- log in as `amor@amor.psi.ch`:
|
|
- open `marche-gui` (unless already open)
|
|
- check for status of
|
|
|
|
- EPICS
|
|
- NICOS
|
|
- `chopper.service`
|
|
- `histogrammer.service`
|
|
- `kafka-to-nexus.target`
|
|
|
|
and probably *stop* / *restart* / *start* the service(s)
|
|
|
|
- I do not remember what this is for:
|
|
|
|
```
|
|
telnet localhost 20000
|
|
^x
|
|
^[
|
|
quit
|
|
```
|
|
|
|
# kafka stuff
|
|
|
|
## check kafka input from `efu`
|
|
|
|
on `amor`:
|
|
|
|
- `source /home/software/virtualenvs/kafka-tools/bin/activate.csh`
|
|
- `kafka-spy -b linkafka01:9092 -t amor_ev44 -C`
|
|
|
|
# NICOS commands
|
|
|
|
## start / stop NICOS
|
|
|
|
in case the Selene pitches MCUs are active, one can deactivate these with
|
|
|
|
amor> caput SQ:AMOR:SEL2.AOUT M714=0
|
|
amor> caput SQ:AMOR:SEL2.AOUT M814=0
|
|
|
|
The **gui** can be launched also by the `amorlnsg` from the console:
|
|
and to launch the gui
|
|
|
|
/home/amor/bin/nicos-gui
|
|
|
|
with
|
|
|
|
user: user
|
|
password: 24lns1
|
|
|
|
## devices and movements
|
|
|
|
In NICOS everything is a device!
|
|
|
|
`ListDevices()`
|
|
|
|
: shows all available devices
|
|
|
|
`read(<device>)`
|
|
|
|
: reads the value of a *device*
|
|
|
|
`maw(<device>, <value> [, <device2>, <value2> ...])`
|
|
|
|
: (move and wait) moves a *device* to *value*
|
|
|
|
`move(<device>, <value>)`
|
|
|
|
: starts moving a *device* to *value* without waiting
|
|
|
|
`wait(<dev1>, <dev2>, ...)`
|
|
|
|
: waits for the listed *devices* to finish
|
|
|
|
`status(<device>)`
|
|
|
|
: queries the status of a *device*
|
|
|
|
`stop()`
|
|
|
|
: stops devices, also Ctr-C, Ctrl-C
|
|
|
|
NICOS devices can have parameters
|
|
|
|
`ListParams(<device>)`
|
|
|
|
: lists the accessible parameters of a *device*
|
|
|
|
`<device>.<parameter>`
|
|
|
|
: queries the value of a *parameter* of *device*
|
|
|
|
`<device>.<parameter>=<value>`
|
|
|
|
: sets a new *value* for a *parameter* of a *device*
|
|
|
|
`ListMethods(<device>)`
|
|
|
|
: lists the methods of a *device*
|
|
|
|
## measurement
|
|
|
|
`count(<mode>=<preset>)`
|
|
|
|
: count with *mode*
|
|
|
|
- `t` = time for *preset* seconds
|
|
- `m` = monitor for *preset* monitor counts
|
|
|
|
`scan(<device>, <start>, <step>, <np>, <mode>=<preset>)`
|
|
|
|
: scan the *device* from *start* with *np* steps of width *step* with the
|
|
counting time defined by *mode* / *preset*
|
|
|
|
`scan(<device>, [<p1>, <p2>, <p3>, <p4>, ... ], <mode>=<preset>)`
|
|
|
|
: scans points *p1, p2, ...* as given in the list
|
|
|
|
`cscan(dev, center, step, np, t=2)`
|
|
|
|
: center-scan: scans *device* around a *center* with *np* steps of width *step* to
|
|
either side.
|
|
|
|
## batch files
|
|
|
|
Batch files are written in python.
|
|
You can use all of python plus the NICOS command set
|
|
|
|
`run(<scriptname>)`
|
|
|
|
: *run* the script *scriptname*, which is either relative to
|
|
`Exp.scriptpath` or has an absolute path
|
|
|
|
`sim(<scriptname>)`
|
|
|
|
: *sim*ulate the script *scriptname*
|
|
|
|
## raw data
|
|
|
|
Location of the raw data files:
|
|
|
|
/home/amor/data/<year>/<proposalname>
|
|
|
|
Location of lof files:
|
|
|
|
/home/amor/nicos/log
|
|
|