20 NOV 2024
11:00 - 12:00

Abstract:

In this talk, I aim to draw attentions to the importance of research on different aspects of hadrons as nonperturbative objects made of quarks and gluons. In particular, introducing the interactions of hadrons with different currents (electromagnetic, weak, strong and graviton-like!) I will discuss how can we get knowledge on the structure of matter, investigate some effects in SM & BSM physics, search for dark matter & dark energy and make scenarios to address the matter-antimatter asymmetry!

Indico Link:
https://indico.hep.ipm.ir/e/k.azizi

Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM

Link to Join Virtually:
https://www.skyroom.online/ch/ipm-particles/weekly-seminar

18 NOV 2024
11:00 - 12:00

Abstract:
In this talk, I present a three-dimensional quasi-static model for high brightness beam dynamics simulation in RF/DC photoinjectors, RF linacs, and similar devices on parallel computers. Although the paper is a little old, I found the idea very interesting and, of course, it is one of the remarkable papers in this field. In this model, electrostatic space-charge forces within a charged particle beam are calculated self-consistently at each time step by solving the three-dimensional Poisson equation in the beam frame and then transforming back to the laboratory frame. When the beam has a large energy spread, it is divided into a number of energy bins or slices so that the space-charge forces are calculated from the contribution of each bin and summed together. Image-charge effects from conducting photocathode are also included efficiently using a shifted-Green function method. For a beam with large aspect ratio, e.g., during emission, an integrated Green function method is used to solve the three-dimensional Poisson equation. Using this model, the authors studied beam transport in one Linac Coherent Light Sources photoinjector design through the first traveling wave linac with initial misalignment with respect to the accelerating axis.

Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM

Link to Join Virtually:
https://www.skyroom.online/ch/ipm-particles/journal-club

13 NOV 2024
11:00 - 12:00

Abstract:
In this colloquium, I'll talk about the chiral effective field theory is used to investigate the spin singlet channel 1S0 of proton-proton (pp) scattering according to the new suggested power counting. For this purpose, the pp zero scattering amplitude is reproduced by inserting one pion exchange at leading order (LO) and the Coulomb interaction between protons at next-to-leading order (NLO). This leads to a systematic improvement up to NLO compared to the result obtained from Nijm93 potential model.

Indico Link:
https://indico.hep.ipm.ir/e/b.behzadmoghaddam

Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM

Link to Join Virtually:
https://meet.google.com/bda-vsem-tuv

11 NOV 2024
11:00 - 12:00

Abstract:

In this talk, we examine the connection between the integrated Polyakov anomaly and the bulk renormalized volume with the recently proposed generalized Liouville action, as discussed in arXiv:2310.17536 [hep-th], on orbifold Riemann surfaces.

Based on:
https://arxiv.org/abs/2310.17536

Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM

Link to Join Virtually:
https://www.skyroom.online/ch/ipm-particles/journal-club

6 NOV 2024
11:00 - 12:00

Abstract:

The proton-radius puzzle refers to the discrepancy observed in measurements of the proton's charge radius when using different methods. This inconsistency has prompted extensive research and debate within the physics community, as it challenges the understanding of quantum electrodynamics and the fundamental properties of protons. In the present study, we determine the charge and magnetic radii of the proton and neutron through a global analysis of the generalized parton distributions (GPDs) at zero skewness for the first time. Our results challenge the measurements or analyses in which the nucleon's radii are extracted considering just a particular experiment or observable, or using only data points covering particular kinematic regions. We emphasize that simultaneous analysis of all available experimental data related to the radii of the nucleons would be preferable to determine their exact values.
The final results obtained from our analysis by this way are: rpE=0.8558±0.0135 fm, rpM=0.8268±0.0533 fm, =−0.1181±0.0270 fm2, and rnM=0.8367±0.0845 fm.

Indico Link:
https://indico.hep.ipm.ir/e/m.goharipour1

Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM

Link to Join Virtually:
https://meet.google.com/bda-vsem-tuv

4 NOV 2024
11:00 - 12:00

Abstract:

In the CMS Phase-2 Upgrade of the RPC Link System, the legacy electronics will be replaced with advanced systems designed to enhance data acquisition from RPC detectors. This upgrade will improve the timing resolution for data taking from 25 ns to an impressive 1.5 ns. However, with the anticipated significant increase in luminosity during the next run in 2028, the interactions of high-energy particles with the link system's electronics are expected to rise dramatically. This surge in luminosity will result in more collisions and, consequently, a substantial increase in the volume of generated data. To address these challenges, both new hardware and effective strategies to mitigate the impact of these collisions—particularly in FPGAs, which serve as the core processing units—are essential. In this presentation, we will introduce the new data acquisition system within the CMS project and provide an overview of key components of the firmware implemented in the FPGA to achieve these objectives.

Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM

Link to Join Virtually:
https://www.skyroom.online/ch/ipm-particles/journal-club

23 OCT 2024
11:00 - 12:00

Abstract:

The main purpose of heavy-ion collision (HIC) is to create a liberated state of quark and gluon to study the macroscopic state of QCD matter. This includes the transport coefficient of the produced plasma as well as mapping the configuration of QCD degrees of freedom in various phases. To achieve this goal, it is crucial to model different stages after the collision, from the formation of the initial state to the final state and hadronization at freeze-out. In this context, the nuclear structure plays an important role in determining the initial conditions of the collision. Understanding the spatial distribution of nucleons and the correlations between them provides essential input to the evolution of the quark-gluon plasma. Particularly, features such as the nuclear deformation, fluctuations in the initial geometry, and two-body correlations influence the final observables, such as collective flow.
In this talk, I will explain, in an ultra-central symmetric collisions and for the particular case of large nuclei, after using certain scale invariance in the process of entropy production, we are able to study the initial state of heavy-ion collision in a model-independent way. This approach enables us to study nuclear structure and extract key information about nuclear geometry, two-body correlation, fluctuations, skin thickness, and etc.

Indico Link:
https://indico.hep.ipm.ir/e/a.tabatabaee

Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM

Link to Join Virtually:
https://meet.google.com/bda-vsem-tuv

21 OCT 2024
11:00 - 12:00

Abstract:

The Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) is designed to detect and analyze high-energy proton-proton collisions. The CMS detector is one of the largest and most complex particle detectors ever constructed, composed of multiple subsystems that work together to identify and measure the properties of particles produced in collisions. The data-taking process in CMS involves several key components, including the Data Acquisition (DAQ) system, trigger system, Data Quality Monitoring (DQM), Detector Control System (DCS), and the Tier-0 computing center. Additionally, the experiment employs advanced data formats and utilizes Monte Carlo simulations to calibrate the detector and compare theoretical predictions with real data. This paper provides a detailed overview of the CMS detector structure and the entire data-taking process, including forward detectors like CTPPS and TOTEM, which enhance CMS's ability to study rare forward proton interactions and diffractive physics. This review also integrates recent updates, including Phase-2 upgrades to the DAQ system for Run 3.

Link to Join Virtually:
https://www.skyroom.online/ch/ipm-particles/journal-club

14 OCT 2024
11:00 - 12:00

Abstract:

Designers and engineers have many options to choose from when con- sidering how to join metals to non- metals for structural, electrical, and pack- aging applications. These options could include mechanical means of fastening such as screws, bolts, rivets and other fasteners, or an elevated-temperature means such as soldering or brazing. Metal-ceramic braz- ing, the topic of this article, is particularly useful for fabricating high-reliability devices such as those used in high-voltage applica- tions or requiring hermetically sealed joints. This article is intended to familiarize the designer with brazing methods commonly used to join metals to ceramics, discuss the advantages and disadvantages of each method, and show the relative tensile strengths obtained from samples fabricated using these methods.

Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM

Link to Join Virtually:
https://www.skyroom.online/ch/ipm-particles/journal-club

9 OCT 2024
11:00 - 12:00

Abstract:

The extraction of parton distribution functions (PDFs) and the strong coupling constant relies heavily on physical observables. Utilizing a variety of appropriate data significantly impacts proton PDFs. In this lecture I will first review the procedure for obtaining new PDF sets. Then, it will explain the constraints imposed by experimental data, such as W/Z boson production, Drell-Yan processes, and jet measurements, on various parton distributions. Finally, it will discuss how simulated data for future colliders can improve PDFs and the strong coupling constant.

Link to Join Virtually:
https://meet.google.com/bda-vsem-tuv