Conveners
Session 9
- Seh Wook Lee (Kyungpook National University (KR))
ATLAS electron and photon triggers covering transverse energies from 5 GeV to
several TeV are essential to record signals for a wide variety of physics:
from Standard Model processes to searches for new phenomena. To cope with
ever-increasing luminosity and more challenging pile-up conditions at a centre-of-mass
energy of 13 TeV, the trigger selections need to be optimized to
control the rates...
The ATLAS Experiment uses a two-level triggering system to identify and
record collision events containing a wide variety of physics signatures.
It reduces the event rate from the bunch-crossing rate of 40 MHz to an
average recording rate of 1 kHz, whilst maintaining high efficiency for
interesting collision events. It is composed of an initial
hardware-based level-1 trigger followed by a...
In 2017 the ATLAS experiment implemented an ensemble of neural networks
(NeuralRinger algorithm) dedicated to improving the performance of
filtering events containing electrons in the high-input rate online
environment of the Large Hadron Collider at CERN, Geneva. The ensemble
employs a concept of calorimetry rings. The training procedure and final
structure of the ensemble are used to...
The CMS experiment implements a sophisticated two-level triggering system composed of the Level-1, instrumented by custom-design hardware boards, and software High Level Trigger. In 2017, the LHC delivered proton-proton collisions at a centre-of-mass energy of 13 TeV with a peak instantaneous luminosity larger than $2 \cdot 10^{34} cm^{-2}s^{-1}$, more than twice the peak luminosity reached...
The Compact Muon Solenoid (CMS) experiment implements a sophisticated two-level triggering system composed of the Level-1, instrumented by custom-design hardware boards, and a software High Level Trigger. A new Level-1 trigger architecture with improved performance is now being used to maintain high physics efficiency for the more challenging conditions experienced during Run II. In this...
Electronics developments are pursued for the trigger readout of the ATLAS Liquid-Argon Calorimeter towards the Phase-I upgrade scheduled in the LHC shut-down period of 2019-2020. The LAr Trigger Digitizer system will digitize 34000 channels at a 40 MHz sampling with 12 bit precision after the bipolar shaper at the front-end system, and transmit to the LAr Digital Processing system in the...
