Month: January 2018

Thesis topic proposal

Design, construct and test a prototype neutron detector

Helium-3 isotope is commonly used as detection medium in detectors applied for neutron detection in many fields of industry and physics. The world crisis of He-3 isotope is forcing for a research and development of other neutron detection methods. Recently, a multigrid gas detector based on boron coated blades has been developed at Institut Laue-Langevin (ILL) in Grenoble as an alternative for commonly applied He-3 proportional counters in neutron scattering experiments. However, it may be considered to use this solution for other applications.

Graduate Seminar 22nd January

Speaker: Joanna Reszczyńska

Title: Hyper-radiosensitivity phenomenon and significance of human individual radiosensitivity in modeling of Low Dose Radiation Biological Effects.

Abstract: For ionization radiation (IR) induced cancer, a linear non-threshold (LNT) model at very low doses is the default used by a number of international organizations and in regulatory law. However, experimental observations and theoretical biology have found that other dose-response curves can exist at those very low doses. This approach includes detailed, molecular descriptions of cells mechanisms to develop a dose-response model either through a set of nonlinear, differential equations or a stochastic approach based on Monte Carlo simulations. Both methods are subject to the body’s reaction.The existence of heritable radiosensitivity syndromes and clinical observations in radiotherapy patients suggests that human cellular radiosensitivity differs among individuals. The assessment of the more radiation-sensitive and the more cancer-prone people is very important issue. This seminar discusses the bases of low-dose hyper-radiosensitivity (HRS) with reference to the molecular regulation of DNA repair and cell cycle control processes. The aim of the presented study was to examine, using the micronucleus (MN) assay, the low-dose radiation response of blood cells lymphocytes from healthy donors and to determine whether the method can be used to verify the hypothesis of the HRS phenomenon occurrence in general population.

Graduate Seminar, 15th January

Speaker: Piotr Kalaczyński

Title: Search for directional correlations of HE muon neutrinos in IceCube and Radio Sources in NVSS

Abstract: The seminar briefly describes IceCube and VLA detectors and the method of angular cross-correlation using power spectra from the multipole expansion of the sky. The analysis aims at determining, whether astrophysical neutrino flux could be originating from extragalactic radio sources contained in the NVSS survey. Since the survey is not exclusively extragalacic, appropriated cuts have to be applied. Performance of the analysis is shown and compared to a standard point-source IceCube analysis.

Graduate seminar, 8th January 2018

Speaker: Paritosh Verma

Title: Gravitational wave signals from highly magnetic accreting millisecond neutron stars

Abstract: This seminar is focused on brief introduction on  gravitational waves as well as their emission from accreting millisecond neutron stars. These binary systems consist of a millisecond pulsar with a rotation period 1-10 ms accreting material from a companion star. Neutron stars can undergo different modes of oscillations, each with different characteristic behavior. Among these, r-modes, or rotational modes, only appear in rotating stars and are caused by the Coriolis force acting as restoring force along the surface of the star. The r-modes have an important role in the physics of millisecond neutron stars: they excite the emission of gravitational waves which carry away energy and angular momentum from the star and lead to differential rotation.