Periodic Reporting for period 3 - OPEN3GEN (Opening the Third Generation: The Search for Long-Lived Fundamental Particles)
Período documentado: 2022-03-01 hasta 2023-08-31
1) The design of a new trigger to record long-lived particles decaying to tau leptons at the ATLAS detector. This is a trigger to record hadronic decay signatures, and simulation shows that this increases the sensitivity to this class of particle by a factor of over two in large lifetime regions.
2) The newly designed trigger was implemented in the trigger menu, meaning that it will be used to record data during the LHC run starting in spring 2022.
3) The hadronic tau identification has been redesigned to be sensitive to long-lived particles decaying to taus. In particular the inclusion of a zero-prong category of taus has more than doubled this sensitivity. In addition to this, the retuning of the recurrent neural network used to identify taus has augmented the sensitivity in the case where charged particles are reconstructed.
4) The analysis framework to search the LHC run 2 data is now advanced, with backgrounds accounted for, and the framework is in place for run 3.
The team has achieved the above aspects of the action with great dedication and productivity throughout the lockdowns.
Novel neural networks trained to provide sensitivity to identify particles decaying from long-lived particles.
Results are expected on new phase space, first in Run 2 ATLAS data and then in the new Run 3 data, which will open up the new searches more strongly as our new triggers will be recording data.