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DT Slice Test Demonstrator Results: October 2020 results

See also: CMS DP-2020/052 Previous results have been reported here

The DT Slice Test

During Long Shutdown 2, 4 DT Chambers (MB1 to MB4 Sector 12 Wheel +2) have been instrumented with Phase-2 on-board DT electronics (OBDT) to setup a demonstrator of the upgraded system called DT Slice Test. The OBDT streams TDC hits from the detector directly to the back-end electronics in the service cavern. These back-end electronics consists of boards hosting Virtex 7 XC7VX330T-3FFG1761E FPGAs. These boards, called AB7, run both event building and a complete version of the DT Analytical Method (AM) algorithm for Trigger Primitive generation.

In the two innermost chambers, the legacy electronics have been fully replaced by the Phase-2 prototypes, while for the outermost, signals coming from a fraction of the chamber frontends are split and sent in parallel to the legacy and to the Phase-2 electronics, so an event-by-event comparison of the response of the two readout and trigger chains is possible.

Slice Test results

Showing new results from the DT Slice Test using Phase-2 Trigger Primitives (obtained running the Analytical Method algorithm either with the AB7 board directly at P5 or with the software emulator) and Phase-1 Trigger Primitives obtained with the Twinmux board.

Considering several qualities depending on how many hits are used for building the Trigger Primitive using both phi Superlayers (4 layers per Superlayer):

- 3/4: 3 hits in one Superlayer.

- 4/4: 4 hits in one Superlayer.

- 6/8: 3 hits in each Superlayer.

- 7/8: 3 hits in one Superlayer and 4 hits in the other.

- 8/8: 4 hits in each Superlayer.

Figure	Caption
	Number of hits associated to the offline reconstructed segment (phi view) versus the quality of the Phase-2 Trigger Primitive obtained by the AB7 board.
	Number of hits associated to the offline reconstructed segment (phi view) versus the quality of the Phase-2 Trigger Primitive obtained by the Emulator.
	Phase-2 vs Phase-1 Trigger Primitive local position comparison for Slice Test data in MB4 Sector 12 Wh+2. Considering the primitive from each system that has the highest quality per event and comparing them only if they have the same quality to suppress wrong combinations. All qualities considered. Eventual ghosts due to potential solutions if different timing cuts are considered do not always match in both systems and generate some outliers. Under investigation.
	Phase-2 vs Phase-1 Trigger Primitive local direction comparison for Slice Test data in MB4 Sector 12 Wh+2. Considering the primitive from each system that has the highest quality per event and comparing them only if they have the same quality to suppress wrong combinations. All qualities considered. Eventual ghosts due to potential solutions if different timing cuts are considered do not always match in both systems and generate some outliers. Under investigation.
	Phase-2 vs Phase-1 Trigger Primitive phi comparison for Slice Test data in MB4 Sector 12 Wh+2. Considering the primitive from each system that has the highest quality per event and comparing them only if they have the same quality to suppress wrong combinations. All qualities considered. Eventual ghosts due to potential solutions if different timing cuts are considered do not always match in both systems and generate some outliers. Under investigation.
	Phase-2 vs Phase-1 Trigger Primitive bending phi comparison for Slice Test data in MB4 Sector 12 Wh+2. Considering the primitive from each system that has the highest quality per event and comparing them only if they have the same quality to suppress wrong combinations. All qualities considered. Eventual ghosts due to potential solutions if different timing cuts are considered do not always match in both systems and generate some outliers. Under investigation.
	Efficiency of finding a Phase-2 Trigger Primitive in any BX with respect to the t0 of the offline segment reconstructed out of hits detected by the Phase-1 system considering every primitive (red), primitives built with more than 4 hits (blue) and primitives with more than 6 hits, i.e. 3 or more hits per Superlayer (green). Selecting segments built with more than 4 hits, which also have an inclination in the radial coordinate smaller than 30º with respect to the direction perpendicular to the chamber. No geometrical matching between the offline segment and the Trigger Primitive is required.
	Efficiency of finding a Phase-2 Trigger Primitive in any BX with respect to the local position of the offline segment reconstructed out of hits detected by the Phase-1 system considering every primitive (red), primitives built with more than 4 hits (blue) and primitives with more than 6 hits, i.e. 3 or more hits per Superlayer (green). Selecting segments built with more than 4 hits, which also have an inclination in the radial coordinate smaller than 30º with respect to the direction perpendicular to the chamber. No geometrical matching between the offline segment and the Trigger Primitive is required. Since one AB7 protoype board only generates primitives from one half of the MB4 chamber, an efficiency drop is visible at the boundary (x=0) between the two regions due to edge effects. The final system will use only one board for the full chamber, so this effect will disappear.

-- JaimeLeonHolgado - 2020-10-28