Uncategorized

Graduate Seminar, 14th January 2019

Speaker: Joanna Reszczyńska

Title: Modelling of human cell reactions to ionizing radiation – from a DNA lesion to a cancer growth

Abstract: Understanding the consequences of exposure to low dose ionizing radiation is an important public health concern. It has become clear that cellular responses can be very different at low compared to high radiation doses. Important biological mechanisms may play key role in dose-response at low doses, which has been described by many deterministic and stochastic models, that try to implement current radiobiological knowledge to experimental data. In this talk, I will discuss post-irradiation cellular processes. I will present dose and time-dependent analytic model of responses of cells in the body to ionizing radiation for two exposure categories: acute and protracted. Special emphasis will be dedicated on the new approach of capturing the key dynamics–formation of the tumour.

Graduate Seminar, 17th December

Speaker: Piotr Kalaczyński

Title: EAS simulations with CORSIKA for KM3NeT

Abstract:  In the talk the design, status and physical goals of the KM3NeT experimental infrastructure will be introduced. Structure of the whole KM3NeT simulation chain and functions of its elements will be explained, but the focus will be on the CORSIKA branch. As a natural extension of this work, an analysis aiming at determining the visibility of the atmospheric charmed component was devised and will be sketched.

Graduate Seminar, 26th November 2018

Speaker: Rahul Nair

Title: Study Of Thermalisation Of Quark Gluon Plasma Using Ultra Relativistic Heavy Ion Collisions

Abstract: In this talk, I will discuss the process of thermalisation of QGP formed at ultra relativistic heavy Ion Collisions. A brief overview of a heavy Ion Collision scenario will be presented. The hydrodynamical calculations together with experimental results points towards a rapid thermalisation of the QGP formed in such a collision. The anisotropic elliptic flow is an indicator of such a thermalisation in the medium. This fact will be discussed and demonstrated using results from Hydrodynamics and data from RHIC and ALICE. I will also explain how the dilepton yield can be used to estimate the thermalisation time of the QGP drop.

Graduate Seminar, 19th November

Speaker: Michał Palczewski

Title: Shapes and sizes of high-K states in SHN

Abstract: Superheavy elements are highly unstable systems with extremely low production cross sections. As the creation of new ones is very difficult, as a parallel or additional line of  study one could try a search for new, long-lived metastable states of already known nuclei. It is well known that an enhanced stability may result from the K-isomerism phenomenon which is based mainly on the (partial) conservation of the K-quantum number. To do such studies energies are calculated within the microscopic – macroscopic approach with the deformed Woods-Saxon potential. Configurations are fixed by a standard blocking procedure and their energy found by a subsequent minimization over deformations. Results of blocking for 2 quasiparticle states (nn or pp)as well as for 4 quasiparitcle states (nnpp) will be shown. The relationship between electric quadrupole moments in different isotopes will be discussed next. Especially some of specific deformation parameters for No isotopes – which are experimentally studied now via laser technique will be demonstrated during the talk. Finally, predictions for Rf and some of heavier elements as: Sg, Hs, Ds and Cn – will be shown.

Graduate Seminar, 5th November

Speaker: Albin Nilsson

Title: Lorentz Violation and Extra Dimensions with Gravity Probe B

Abstract: The satellite experiment Gravity Probe B uses four gyroscopes to test General Relativity using the gravity well of the Earth through the de Sitter and Lens-Thirring effects. However, the errors from this experiment are quite large, which allows for alternative explanations of the data through modifications of General Relativity. In this talk I will describe the theory and experimental setup of Gravity Probe B, along with its main results. I will then outline how these results could be used to put constraints on some of the Standard Model Extension (SME) parameters, which is an effective field theory framework for Lorentz and CPT violation. Finally, I will describe how this discrepancy between theory and experiment could be attributed to the existence of extra spatial dimensions.

Graduate Seminar, 29th October

Speaker: Michał Palczewski

Title: Shapes and sizes of high-K states in SHN

Abstract: Superheavy elements are highly unstable systems with extremely low production cross sections. As the creation of new ones is very difficult, as a parallel or additional line of  study one could try a search for new, long-lived metastable states of already known nuclei. It is well known that an enhanced stability may result from the K-isomerism phenomenon which is based mainly on the (partial) conservation of the K-quantum number. To do such studies energies are calculated within the microscopic – macroscopic approach with the deformed Woods-Saxon potential. Configurations are fixed by a standard blocking procedure and their energy found by a subsequent minimization over deformations. Results of blocking for 2 quasiparticle states (nn or pp)as well as for 4 quasiparitcle states (nnpp) will be shown. The relationship between electric quadrupole moments in different isotopes will be discussed next. Especially some of specific deformation parameters for No isotopes – which are experimentally studied now via laser technique will be demonstrated during the talk. Finally, predictions for Rf and some of heavier elements as: Sg, Hs, Ds and Cn – will be shown.

Graduate seminar, 8th October

Speaker: Paweł Kowalski

Title: Design and optimization of the strip PET scanner based on plastic scintillators

Abstract: The novel whole-body PET system based on plastic scintillators is developed by the J-PET Collaboration. It consists of plastic scintillator strips arranged axially in the form of a cylinder, allowing the cost-effective construction of the total-body PET. In order to determine properties of the scanner prototype and optimize its geometry, advanced computer simulations using the GATE software were performed. The spatial resolution, the sensitivity, the scatter fraction and the noise equivalent count rate were estimated according to the NEMA norm as a function of the length of the tomograph, number of the detection layers, diameter of the tomographic chamber and for various types of the applied readout. Results of simulations of these characteristics will be presented during the talk.