LIT Seminar, July 21 (Wednesday) 2021, 15:00, LIT conference-hall and online

Joint JINR Seminar, July 21, 2021 (Wednesday), 16:00, online

"Measuring intact protons at the LHC: From the odderon discovery to the search for axion-like particles"

Prof. Christophe Royon (The University of Kansas, Lawrence, USA)

In the first part of the talk, we will describe the odderon discovery by the TOTEM and D0 experiments. The analysis compares the proton-antiproton elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV. The two data sets disagree at the 3.4 sigma level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in pp scattering, leading to a combined significance larger than 5 sigma. In a second part of the talk, we will describe the perspective on the search for quartic anomalous couplings and axion-like particles using tagged protons in the final state, leading to sensitivities to beyond standard model physics that improve by 2 to 3 orders of magnitude on the coupling. We will finish by describing briefly the ultra fast silicon detectors for timing measurements as well as for medical and cosmic ray physics applications.

Joint JINR Seminar, July 7, 2021 (Wednesday), 10:00, at the Conference Hall of Bogoliubov Laboratory of Theoretical Physics JINR and online

"Super c-tau factory: precision experiments with tau lepton and charmed hadrons"

Vorobyev V.S. (Senior researcher, BINP SB RAS)
Levichev E.B. (Vice-director of BINP SB RAS)
Logashenko I.B. (Vice-director of BINP SB RAS)

The discovery of the Higgs boson in 2021 completed confirmation of the Standard model (SM) of particle physics. However, SM is not the final theory of matter. A major goal of modern high energy physics is search for phenomena beyond SM (BSM) that can manifest itself as the new fundamental particles or via discrepancies between the results of precision measurements and the SM predictions.

The “Crab waist” particle beams collision scheme, proposed in 2006, paved the way for the new generation of colliders - super factories - with a luminosity two orders of magnitude higher than that of modern machines. The super B factory SuperKEKB in Japan and the planned Z and Higgs factory FCC-ee at CERN are based on this principle. The Super c-tau (SCT) factory is a project of the super-factory-class collider aimed at the threshold production of tau leptons and charmed hadrons, their comprehensive and detailed study and the search for the BSM phenomena. The SCT factory project includes longitudinal polarization of the electron beam at the collision point, which significantly enriches the physical program of the experiment.

The presentation includes discussion of the place of the SCT factory in the landscape of modern high energy physics and provides an overview of the physics program and a conceptual design of the accelerator complex and particle detector.

FLNP SEMINAR, June 17, 2021 (Thursday) at 11:00, online

"A source of ultracold neutrons slowed down by a magnetic or material UCN trap"

V.V.Nesvizhevsky (Nuclear & Particle Physics Department, ILL, Grenoble, France)

Ultracold neutrons (UCNs) are widely used in the physics of elementary particles and fundamental interactions, and can potentially be used in neutron scattering. However, most of these studies are limited by the available UCN densities and fluxes. One of the ways to increase them, as noted already in the first years of research with UCN, is to use peak fluxes in pulsed neutron sources, orders of magnitude higher than the average. In the present work, the concept of UCN sources is proposed, which makes it possible to implement this idea. We propose to produce very cold neutrons (VCN) in converters located in neutron sources and extract them with low losses. We propose a new way of focusing them in time, as well as their deceleration to UCN energies by an escaping decelerating material or magnetic trap. For both pulsed and permanent neutron sources, this method can provide high conversion efficiency of VCN to UCN.

DSC FLNP SEMINAR, June 18 (Friday), 11:00, online

"Algorithms and programs for express-analysis of data in List-Mode of neutron scattering, measured on 2-axis PSDs with a delay line using data acquisition systems based on CAEN digitizers"

Litvinenko E.I.

When using CAEN digitizers, serving as electronics of general use, in the considered case of 2-axis PSDs with a delay line, the task of constructing neutron events from measured data should be performed at the software level. The statement of problem and the developed software for a sufficiently fast transformation of the measured data into formats that allow obtaining and visualizing the positional and time-of-flight spectra of neutrons in the process or immediately after the end of the current measurement are described in the paper.