10 JUL 2024
11:00 - 12:00

Abstract:

Neutral current Drell-Yan (DY) lepton-pair production is considered in the framework of the Standard Model Effective Field Theory (SMEFT). Using the open-source fit platform xFitter, we investigate the impact of high-statistics measurements of the neutral current DY (NCDY) forward-backward asymmetry AFB near the weak boson mass scale in the present and forthcoming stages of the Large Hadron Collider (LHC). Besides recovering earlier results on the AFB sensitivity to parton distribution functions, we analyze the precision determination of Z-boson couplings to left-handed and right-handed u-quarks and d-quarks, and explore Beyond-Standard-Model contributions using the SMEFT framework. We comment on the role of the AFB asymmetry for the electroweak SMEFT fit and precision Z-boson physics at the LHC and high-luminosity HL-LHC.

Indico Link:
https://indico.hep.ipm.ir/e/h.abdolmaleki2

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

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

8 JUL 2024
11:00 - 12:00

Abstract:

Light-front wavefunction of a hadronic bound state is factorized into transverse and longitudinal modes. In holographic QCD, the transverse mode is the solution of a Schr\"odinger-like equation which is derived based on the AdS$_5$/CFT correspondence. The longitudinal mode, on the other hand, is non-dynamical in holographic QCD. Here, I discuss the shortcomings of this picture and examine the phenomenological consequences of a dynamical longitudinal mode which is obtained from the 't Hooft Equation.

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

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

3 JUL 2024
11:00 - 12:00

Abstract:

In this study, we investigate the sensitivity of the Cherenkov Telescope Array (CTA) and Fermi Large Area Telescope (Fermi-LAT) to dark matter (DM) annihilation in γ-ray lines. We focus on observations of the Galactic Center (GC), dwarf Spheroidal galaxies (dSphs), and galaxy clusters (GCls). Specifically, we compare the reach of the GC with that of dSphs, considering the poorly known putative core radius of the DM distribution. Surprisingly, we find that the currently best dSph candidates present a more promising target than the GC, especially for core radii ranging from one to a few kiloparsecs.
In addition to CTA prospects, we extend our analysis to incorporate Fermi-LAT data. Recent advancements in computations have highlighted the impact of Sommerfeld enhancement and bound-state formation on the annihilation cross section of Minimal Dark Matter (MDM) multiplets. Exploring this new paradigm, we examine Fermi-LAT data to assess its capability to detect or rule out a potential line arising from bound-state formation processes. Our findings reveal that the Fermi-LAT data effectively rules out the MDM 5plet at a significance level of 2σ, demonstrating the importance of considering enhanced cross sections and new annihilation signatures in the quest to unravel the mysteries of dark matter.

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

Link to join the webinar:
https://meet.google.com/bda-vsem-tuv

1 JUL 2024
11:00 - 12:00

Abstract:

The search for an effective solution to the problem of pumping conductance-limited vacuum systems, as those for particle accelerators, lead, at the end of 1995, to the start of the development of Non-Evaporable Getters (NEG) thin film coatings at CERN. Coating the whole inner surface of a vacuum chamber, after dissolving the NEG oxide layer by heating (activation), transforms it from a source of
gas into a pump providing very high pumping speed per unit length. In this talk, we will present the NEG physics and also describe how discharge voltage, magnetic field strength, and pressure effect on the deposition rate.

Based on:
https://arxiv.org/pdf/2006.01537

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

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

26 JUN 2024
11:00 - 12:00

Abstract:

Sustainability in particle accelerator facilities is essential for advancing scientific research while minimizing environmental impact. This involves implementing energy-efficient technologies, optimizing resource use, and adopting sustainable practices in facility operations. By reducing energy consumption, utilizing renewable energy sources, and managing waste effectively, particle accelerators can significantly lower their carbon footprint. Furthermore, integrating sustainable design principles in the construction and maintenance of these facilities ensures long-term environmental stewardship. This presentation explores various strategies and innovations that enhance the sustainability of particle accelerator facilities, highlighting their role in promoting eco-friendly scientific advancement.

Indico Link:
https://indico.hep.ipm.ir/e/s.ahmadian

Link to join the webinar:
https://meet.google.com/bda-vsem-tuv