Dectris Mythen strip (1D) detector controller¶
The Mythen is a 1D,strip , detector based on hybrid pixel technology made by Dectric company. It can operate at 1000Hz, 24-bit, with a readout time of 89us. Its energy range is from 4 to 40 keV (down to 4keV only for 320um x 4 mm sensors). Threshold and energy in keV can be selected.
The Mythen strip detector is commonly used as MCA-like detector in the field of spectroscopy application.
There are actually two versions of Mythen hardware, so-called Mythen and Mythen2, the BLISS controller supports both systems.
The Mythen is a networked device which can be configured for a fix IP address. An embedded web client is running in the Detector Control System4 (DCS4) box. The DCS4 is delivered from factory with IP address 192.168.0.90.
The Mythen web client can be used to test the detector, it provides a full access to the detector configuration and the acquisition.
Configuration example from ID10 EH1¶
- name: mythen1 module: mca.mythen class: Mythen plugin: bliss hostname: mythenid101 apply_defaults: True # Reset all the settings to their default value, it applies a reset command, see dectris manual for reset values energy: 10 # keV threshold: 5 # kev - name: mythen2 module: mca.mythen class: Mythen plugin: bliss hostname: mythenid102 apply_defaults: True energy: 12
Above example works in case there is a __init__.yml in the same directory containing:
plugin: bliss
Full list of configuration with default values¶
| Setting | Possible values | Default | Unit |
|---|---|---|---|
| nmodules | 1-4 | 1 | int. |
| delay_after_frame | 0-N | 0.0 | sec. |
| nframes | 1-N | 1 | int. |
| nbits | 4,8,16,24 | 24 | bit |
| exposure_time | 1e-7-N | 1.0 | sec. |
| energy | Emin-Emax (1) | 8.05 | keV |
| threshold | Thrmin-Thrmax (1) | 1 | keV |
| bad_channel_interpolation | True,False | True | bool. |
| flat_field_correction | True,False | True | bool. |
| rate_correction | True,False | False | bool. |
| rate_correction_deadtime | 0-N | N/A | sec. |
| continuous_trigger_mode | True,False | False | bool. |
| single_trigger_mode | True,False | False | bool. |
| delay_before_frame | 1e-7-N | 0.0 | sec. |
| gate_mode | True,False | False | bool. |
| ngates | 1-N | 1 | int. |
| input_polarity | 0,1 (2) | 0 | int. |
| output_polarity | 0,1 (2) | 0 | int. |
| selected_module | 0-N | 0 | int. |
| element_settings | Cu,Mo,Cr,Ag | Cu | N/A |
(1) : The supported energy and threshold ranges depend on the module type, see the detector manual for the ranges.
(2) : in/out polarity change is deprecated from mythen controller model DCS4.
Sample Tricks¶
The mythen has low level commands for energy/threshold/correction/deadtime
settings and a high level command element_settings with predefined settings
for Copper, Molybdenum, Chromium or Silver tube. Changing the element_settings
will apply new values for the low levet settings.
From the Mythen controller object you can display the settings in one shot:
TEST_MYTHEN [1]: mythen2 = config.get('mythenid102') TEST_MYTHEN [3]: mythen2 Out [3]: Mythen on mythenid102: nmodules = 2 delay_after_frame = 0.0 nframes = 1 nbits = 24 exposure_time = 1.0 energy = (22.16, 22.16) threshold = (11.08, 11.08) bad_channel_interpolation = True flat_field_correction = True rate_correction = False rate_correction_deadtime = (1.3882828e-07, 1.3525846e-07) continuous_trigger_mode = False single_trigger_mode = False delay_before_frame = 0.0 gate_mode = False ngates = 1 selected_module = 0 element_settings = ('Ag', 'Ag')
Some Mythen commands (energy, threshold, element_settings …) apply on the
selected module. The DCS4 can control up to 4 modules and you can choose to
select all (default) on only one. The attribute selected_module gives
access to this:
TEST_MYTHEN [4]: mythen2.selected_module Out [4]: 0 # means all selected TEST_MYTHEN [5]: mythen2.selected_module=2 #select module number 2 TEST_MYTHEN [6]: mythen2.element_settings='Cu' # change settings of module #2 to Cu TEST_MYTHEN [8]: mythen2 Out [8]: Mythen on mythenid102: nmodules = 2 delay_after_frame = 0.0 nframes = 1 nbits = 24 exposure_time = 1.0 energy = (22.16, 8.05) threshold = (11.08, 6.4) bad_channel_interpolation = True flat_field_correction = True rate_correction = False rate_correction_deadtime = (1.3882828e-07, 2.3231377e-07) continuous_trigger_mode = False single_trigger_mode = False delay_before_frame = 0.0 gate_mode = False ngates = 1 selected_module = 2 element_settings = ('Ag', 'Cu')