No Arabic abstract
This paper explores the physics reach of the proton-proton Future Circular Collider (FCC-hh) and of the High-Energy LHC (HE-LHC) for searches of new particles produced in the $s$-channel and decaying to two high-energy leptons, jets (non-tops), tops or W/Z bosons. We discuss the expected discovery potential and exclusion limits for benchmark models predicting new massive particles that result in resonant structures in the invariant mass spectrum. We also present a detailed study of the HE-LHC potential to discriminate among different models, for a $Z$ that could be discovered by the end of High-Luminosity LHC (HL-LHC).
The LHC trigger and data acquisition systems will need significant modifications to operate at the HL-LHC. Due to the increased occupancy of each crossing, Level-1 trigger systems would experience degraded performance of the LHC algorithms presently selecting up to 100 kHz of crossings from the LHC input rate of 40 MHz. The DAQ systems will experience larger event sizes due to greater occupancy and higher channel counts of new detectors. This paper summarizes findings and recommendations to upgrade the LHC experiments trigger and data acquisition systems for operation at the HL-HLC.
First of all, an importance of the LHC and FCC based energy frontier lepton-hadron and photon-hadron colliders is emphasised. Then arguments favoring existence of new heavy isosinglet down-type quarks and vector-like isosinglet or isodoublet leptons are presented, following by historical arguments favoring new (preonic) level of matter. The importance of Super-Charm factory and GeV energy proton linac for Turkey national road map is argued. Finally, several recommendations for ESPP2020 are suggested.
QCD instantons are arguably the best motivated yet unobserved nonperturbative effects predicted by the Standard Model. A discovery and detailed study of instanton-generated processes at colliders would provide a new window into the phenomenological exploration of QCD and a vastly improved fundamental understanding of its non-perturbative dynamics. Building on the optical theorem, we numerically calculate the total instanton cross-section from the elastic scattering amplitude, also including quantum effects arising from resummed perturbative exchanges between hard gluons in the initial state, thereby improving in accuracy on previous results. Although QCD instanton processes are predicted to be produced with a large scattering cross-section at small centre-of-mass partonic energies, discovering them at hadron colliders is a challenging task that requires dedicated search strategies. We evaluate the sensitivity of high-luminosity LHC runs, as well as low-luminosity LHC and Tevatron runs. We find that LHC low-luminosity runs in particular, which do not suffer from large pileup and trigger thresholds, show a very good sensitivity for discovering QCD instanton-generated processes.
In multiscale and topcolor-assisted models of walking technicolor, relatively light spin-one technihadrons $rho_T$ and $omega_T$ exist and are expected to decay as $rho_T to W pi_T, Z pi_T$ and $omega_T to gamma pi_T$. For $M_{rho_T} simeq 200 GeV$ and $M_{pi_T} simeq 100 GeV$, these processes have cross sections in the picobarn range in $bar p p$ colisions at the Tevatron and about 10 times larger at the Large Hadron Collider. We demonstrate their detectability with simulations appropriate to Run II conditions at the Tevatron.
We investigate heavy-quark production as a function of the rapidity interval between two heavy quarks in hadronic collisions. We compare the results relevant to bottom production at the Tevatron and at LHC, obtained using exact leading-order and NLO pQCD production, as well as the contribution of the 4b channel with and without the addition of BFKL gluon radiation.