Overview

The beamtime on July 21 is the final shift of the dec 2022 epix10ka calibration beamtimes. From the December beam times two primary problems were observed, the check mark problem for the small 10k's and 3 out of the 4 quads of the MFX 2M showing values that were too low after switching.

       Fig. 1 AML-L linearity behavior for small ePix10ka.           Fig. 2 AML-L linearity compared to FL linearity for small epix10ka.

Fig 3. The observed problem when switching for 3 of the quads for the ePix10k2M.1.

We believe the problem is due to the X-ray pulse arriving to early in the measurement cycle, and only partially within the ACQ window, For the upcoming beamtimes 4 detectors will be evaluated: epix10ka front facing (no. 27), epix10ka sidefacing 1mm Si, ePix10k2M.1, and a prototype of the ePix10ka non-ghosting ASIC (NG). For the first 2 shifts, the primary aims are (in order of importance):

1. Evaluate the problems observed for the 2M and the smalls and correct these, so we can properly calibrate the smalls during the final beamtime.
2. to evaluate the linearity and switching dependence on the total flux hitting the detector, i.e. pinhole experiment;
3. to evaluate the magnitude of the tigerteeth in switching when running with CompEnOn and Off,
4. evaluate the performance of the NG detector (linearity, switching, ghosting).

The aim of the final shift is to calibrate the small ePix10ka detectors when we have corrected the problems observed in December so we have valid calibration data for all detectors. For all 3 beam times, we will be set up to measure airscatter at different fluxes. Prior to going to the beamtime, the following work has to be done:

1. DAQ scripts for time scan and intensity scans have to be identified and tested that they run,
2. python visulisations for a few pixels that show both linearity (ADU vs. wave-8), and the timing scans (delay vs measured average intensity); evaluation of dropped shots to see if there is any persistance.
3. as well as the scope setup allowing us to see the x-ray pulse position compared to ACQ window has to be verified and ready;

Shift coverage and responsibility

Visulisation and DAQ scripts: Philip, Bhavna, Xavier;

Hardware setup and running the DAQ: Conny, Kaz, Dionisio.

Experimental setup

Measurement plan:

15 July 2023(?):

epix10ksmall, front facing, side facing, NG installed. Ensure we have dropped shots at a reasonable ratio for drift behavior monitoring and persistence for the NG detector.

Evaluation of the checkmark for the small:

Timing scan for the small the small detectors to identify the ACQ window position. The very crudely measured transfer function performed during the december beamtime for the small 10k can be seen below (Fig. 4)

1. Perform an intensity scan at the correct location and visualize to evaluate the performance of the Wave-8 and find a wave-8 combination that works for the setup; 5 pedestal run before each. Visualize in real time.
2. Step through the rising edge of the transfer window. At each location, perform an intensity scan in AML to check the linearity behaviour as a function of how close to full in the window we are. 5 pedestal run intermittently. Visualize in real time.

Discuss the stepsize and range!

Fig 4. Transfer function epix10k small. Original delay shown acqtoasicrodelay = 18223.OOriginal acqtoasicr0delay=18223riginal acqtoasicr0delay=18223Original acqtoasicr0delay=18223

Pinhole experiment and Comp en on & off:

Evaluate the tiger teeth effect for Comp_en_on and off; Evaluate the linear response and if it changes when doing intensity scans with the entire sensor area exposed (no pin-hole) and if only a small region is exposed (pin-hole)

1. locate the pulse at correct location in timing window (determined above); then perform an intensity scans with the whole detector exposed, but CompEnOn set to off; 5 pedestal before each measurement. Visualize in real time.
2.  Perform 2 intensity scans with the whole detector exposed, but CompEnOn set to on; 5 pedestal before the runs. Visualize in real time.
3. Install the pinhole mask in front of the camera and perform 2 additional intensity scans. 5 pedestal before measurements. Visualize in real time.
4. Remove pinhole mask and collect data for 1 minute with high intensity to evaluate the dropped shots. 5 pedestal before measurements. Visualize in real time.
5. was there something else from Philip related to the low vs AML response?

15 July 2023 or 21 July (?):

ePix10k2M.1.

Timing scan for ePix10k2M to identify the ACQ window position. The transfer function measured for this camera in Jan 2022 can be seen below (Fig. 5)

1. Perform an intensity scan at the correct location and visualize to evaluate the performance of the Wave-8 and find a wave-8 combination that works for the setup; 5 pedestal run before each. Visualize in real time.
2. Step through the rising edge of the transfer window. At each location, perform an intensity scan in AML to check the linearity behaviour as a function of how close to full in the window we are. 5 pedestal run intermittently. Visualize in real time.

Discuss the stepsize and range!

Fig 4. Transfer function epix10k small. Original delay acqtoasicrodelay = ? check from data.OO

21 July 2023 or 22 July (?):

Full calibration of the small ePix10k's (from, side, NG). Make sure we use dropped shots.

File containing the run number descriptions: