Timepix-3 (TPX3) Luminosity Determination of LHC Proton-Proton Collisions at 13 TeV
Andre Sopczak
IEAP CTU in Prague
Abstract: The Medipix (MPX) and Timepix (TPX) devices installed in the ATLAS cavern have made important contributions to the overall LHC luminosity determinations. We demonstrate for the first time that the Timepix-3 chip (TPX3) as the next generation of X-ray and radiation imaging technology can be used for precision luminosity measurements. Rather than collecting data frame-by-frame the TPX3 device generates a continuous stream of data. Thus, new analysis techniques were applied for the luminosity determination.
The data of a TPX3 device operating in a first phase in the ATLAS cavern was analyzed. For the luminosity determination of the LHC proton-proton collisions, Luminosity Blocks (LBs) of typically 60 seconds were defined. These LBs were used to determine LHC luminosity curves reflecting the luminosity reduction from single-bunch interactions and from beam-beam interactions. From these measurements, the internal long-term time-stability of the TPX3 luminosity was determined. In addition, the linearity of the TPX3 luminosity measurements with respect to other luminosity measurements was determined as a function of the average number of interactions per bunch crossing. Furthermore, the long-term stability of the TPX3 luminosity measurements was determined by comparisons to reference measurements of other luminometers, and good agreement was found. TPX3 with a time precision up to 1.56 ns has proven to measure the luminosity of individual LHC bunches, rather than bunch-integrated luminosity.
Seminar takes place on Tuesday, October 2nd 2018 at 2:00 PM
in the IEAP meeting room, Praha 2 ‐ Albertov, Horská 3a/22.
| doc. Dr. André Sopczak seminar organizer |
doc. Ing. Ivan Štekl, CSc. director of IEAP |
doc. Dr. André Sopczak IEEE CS - NPSS chair |
NUCLEAR & PLASMA SCIENCES SOCIETY CHAPTER
IEEE Czechoslovakia section
http://www.ieee.cz/en/nps