Skip to content

UE52 SGM beamline

This is the cookbook for using bluesky at the UE52-SGM Beamline. Many examples and many commands are explicitly written in a form that is easy for the user/operator to simply copy and paste them into the bluesky terminal as they are or with little modification.

Start Bluesky

From a terminal write

bluesky_start

Start Keithleys Screens

To start the screen for the keithlys run this line in a terminal:

docker run --rm --network host --env DISPLAY=$DISPLAY -v="$HOME/.Xauthority:/root/.Xauthority:rw" -v ./gui:/opt/phoebus/gui -v /tmp/.X11-unix:/tmp/.X11-unix --device=/dev/dri:/dev/dri registry.hzdr.de/hzb/epics/phoebus-container:latest

Then click on the file browser button and select the four Keithleys. You can also detach the screens to be able to see the four of them together.

Devices in the Beamline

The devices in the beamline have different components. To see the different component of a device use device.component_names. For instance, to see the component of the plane grating monochromator, called pgm, use pgm.component_names

In general one can manipulate each component by referring to it as device.component. For example the energy of the monochromator is pgm.en.

Accelerator

label: accelerator

Motor Description Units
acc.current The ring current mA
next_injection.time_next_injection Next injection time sec

Keithleys

label: apertures

Motor Description Units
kth1.current Model 6517B ...
kth2.current Model 6517B ...
kth3.current Model 6514 ...
kth4.current Model 6514 ...

Water Apertures

label: apertures

Motor Description Units
wau1.top Top aperture mm
wau1.bottom Bottom aperture mm
wau1.left Left aperture mm
wau1.right Right aperture mm

First Mirror

label: mirrors

Motor Description Units
m1.tx Translation in X µm
m1.ty Translation in Y µm
m1.tz Translation in Z µm
m1.rx Rotation about X axis rad
m1.ry Rotation about Y axis rad
m1.rz Rotation about Z axis rad

Plane Grating Monochromator

label: pgm

Motor Description Units
sgm.en Energy eV
sgm.cff Constant fix focus factor a.u.
sgm.diff_order Diffraction Order a.u.
sgm.slitwidth Exit Slit width µm
sgm.grating The grating that is being used l/mm

Move motors and set values

Move motors

If you want to move a motor, or a set of motors you can simply type:

mov motor1 position1 motor2 position2

or using relative motions

movr motor1 relative_motion1 motor2 relative_motion2

A progress bar will be shown, the last number on the right is the current motor position (this works when you move only one motor)

Progress Bar

Set Values

If you want to set a value, for instance a new cff for the monochromator, use the following syntax

device.axis.set(value)

Change the plange grating monochromator cff

To set the cff value to 2.5 use:

sgm.cff.set(2.5)

Note that this will not produce any movement in the monochromator. The new cff will be set once you change the energy to a new one.

Magics

  • ct will show a reading of all the detectors
  • wa will show all the motor positions. You can select which motors to show using their label. For instance wa reflectometer will show only the reflectometer motor positions.

Data

Specfile

The data are exported in a spec file, located in /home/opticsmaster/blusky/data/beamline_commissioningYEAR.

Individual csv files

Additionally, individual csv files are exported in /home/opticsmaster/blusky/data/beamline_commissioning/csv.

Change User

To change the folder where the single csv files are exported use the following command:

  • changeuser("user_name")

This will create a folder called /home/opticsmaster/blusky/data/user_name/csv where the files will be exported.

Three kind of files will be exported for each scan:

  • scanNumber_baseline.csv: here are contained the measured values for all the devices in the baseline (measured once before and once after the scan)
  • scanNumber_meta.json: here are contained the metadata relative to the scan
  • scanNumber_primary.csv: here are contained the data for the scan.

Scan Types

Several scan types are available by default in Bluesky. For a complete list and the documentation refer to the official documentation

Original syntax

Plans have to be passed as an argument to the Run Engine, and they are functions themselfs. For instance the count plan should be invoked like this: RE(count([noisy_det],5,delay=1))

Simplified syntax

Experimental ipython magics are available that aim to simplify the syntax. By prefixing the symbol % to the plan name, it is possible to use a spec-like syntax. For instance, the same count plan as above can be invoked like this: %count [noisy_det] 5 delay=1

In case of problems, please report it to the beamline scientist and use the original syntax.

  • count: take one or more readings from detectors. Usage (5 counts, 1 sec delay):

    • %count [noisy_det] 5 delay=1

  • scan or ascan: scan over one multi-motor trajectory. Usage (scan motor1 between -1 and 1 in 10 points)

    • %ascan [noisy_det] motor1 -1 1 10

  • relative_scan or dscan: scan over one multi-motor trajectory relative to current position. Usage (scan motor1 between -1 and 1 in 10 points)

    • %dscan [noisy_det] motor1 -1 1 10

  • list_scan: scan over one or more variables in steps simultaneously (inner product). Usage (scan motor1 on a list of given points)

    • %dscan [noisy_det] motor1 [point1, point2, ...]

Average measurement for each point

When measuring with the Keithleys, it is possible to instruct them to repeat the measurement n times, and return the averaged value.

To do this we have to set the parameter avg_num of the Keithley to the desired value, by default is 1. For instance, to change it to 5, for each Keithley, give the following commands

kth1.avg_type.set('Repeat')
kth1.avg_num.put(5)

kth2.avg_type.set('Repeat')
kth2.avg_num.put(5)

kth3.avg_type.set('Repeat')
kth3.avg_num.put(5)

kth4.avg_type.set('Repeat')
kth4.avg_num.put(5)

Settle Time (wait before measuring)

It is possible to define a settle time, which is a a number of seconds waited by a motor before reporting that the motion is completed. For instance, to set the settle time of the pgm.en axis, use:

pgm.en.settle_time = 5

Settle Time for all motors

The following function will change the value of the settle time for all the motors to the desired value. For instance to change it to 2 or to 5 seconds use onew of the following

settle_time(2)

settle_time(5)

Add metadata to the scans

Custom metadata can be entered by the user at the execution time of a plan. Suppose that we are exectuing a plan called scan() (for brevity we omit the parameters that we need to pass to the scan function). One can add the metadata either like this:

  • RE(scan(), operator='John', sample='pure_gold')

Another way is to add the metadata directly in the plan. In this case we need to use a python dictionary.

  • RE(scan([det], motor, 1, 5, 5, md={'operator':'John', 'sample':'gold'}))

or using the symplified syntax:

  • %scan [det] motor 1 5 5 md={'operator':'John','sample':'gold'}

Abort Motion

Weather you are moving a motor or running a plan, the motion can be interrupted by pressing ctrl+c.

This will work for the hios and the pgm.en motors.

Suspenders

Bluesky can automatically pause a measurement in case some conditions are met, by using suspenders. Two suspenders can be activated.

wait_for_injection

This suspender pause the measurements two seconds before and after the injection happens. To activate it and deactivate it use

wait_for_injections()

check_beamshutter

This suspender pause the measurements if it detects that the beamshutter or the last valve are closed. To activate it and deactivate it use

check_beamshutter()

How to write a script

Make a folder with your name in /home/opticsmasters/bluesky/user_scripts/your_name. You can then write your scripts in that folder. Examples are available in that folder /home/opticsmasters/bluesky/user_scripts/examples

The commands that are normally written in the ipython terminal should be passed as an argument to the function run_plan(), as in the examples below.

One can wriute either procedural scripts, where each line will be executed one after the other one like in the example below. To run this script just type load_user_script('examples/example_script.py'

# print the pocurrent energy of the monochromator
print(f"Current position of the PGM {pgm.en.get()}")

# move the energy to 403 eV
run_plan("%mov pgm.en 403")

# run a scan
run_plan("%dscan [noisy_det] motor -1 1 10")

Or it is possible to define functions to call from the command line. To run this script just type load_user_script('examples/example_with_functions.py'). Now the function test_plan() is available in the ipython session, so just type test_plan() to execute it

def test_plan():
    # print the pocurrent energy of the monochromator
    print(f"Current position of the PGM {pgm.en.get()}")

    # move the energy to 403 eV
    run_plan("%mov pgm.en 403")

    # run a scan
    run_plan("%dscan [noisy_det] motor -1 1 10")

Moxa Box

It is registered in the DNS/DHCP with name: moxa01.exp0101.bessy.de and address 172.31.4.110

Portainer

Portainer is availbale at this link.

Pw should be the same of the pc + 123, I dont remember the username

Experts Section

If you are a user, this section is not for you.

Additional command to start bluesky

Bluesky is running in containers. To restart the containers use:

bluesky_start restart

To bring down the containers:

bluesky_start down

To enter the container to debug:

bluesky_start sh

Containers Running on the local machine

This section describes which containers are running on the local machine. If you are an user, this section is of no use for you.

To visualize the running containers, you can use either Portainer (see section above), or VSCode.

Bluesky

  • bluesky (The container containing the bluesky environment)
  • Mongo (the database where bluesky saves the data)
  • Tiled (a data-access service used to connect to the mongoDB catalog)
  • Graphana (to monitor and PVs with a GUI, not necessary to run bluesky)
  • MongoExpress (to monitor the usage of the MongoDB)
  • Portainer (to visualize/mange the running containers)

EPICS

  • Keithley IOC (this is the IOC used to connect to the keithleys)
  • UserValues reflectometer (this containers reads the PV exposed by the labview program and exposes a new set of PV with a simpler logic to implement in Ophyd)
  • Phoebus (this is the container with phoebus, we use is to visualize the keithleys screens)