BrainMap

Mr. Andrei Neacsu

Senior Researcher

Researcher - CENTRUL INTERNAŢIONAL PENTRU PREGĂTIRE AVANSATĂ ŞI CERCETARE ÎN FIZICĂ-FILIALĂ A INCDFM BUCUREŞTI

Researcher | Teaching staff

Web of Science ResearcherID: L-5363-2013

Curriculum Vitae (12/08/2019)

Expertise & keywords

Investigations of beyond standard model physics from theoretical studies of double-beta decay Call name: P 1 - SP 1.1 - Proiecte de cercetare pentru stimularea tinerelor echipe independente - TE-2021
PN-III-P1-1.1-TE-2021-0343 2022 - 2024

Role in this project:

Coordinating institution: CENTRUL INTERNAŢIONAL PENTRU PREGĂTIRE AVANSATĂ ŞI CERCETARE ÎN FIZICĂ-FILIALĂ A INCDFM BUCUREŞTI

Project partners: CENTRUL INTERNAŢIONAL PENTRU PREGĂTIRE AVANSATĂ ŞI CERCETARE ÎN FIZICĂ-FILIALĂ A INCDFM BUCUREŞTI (RO)

Affiliation:

Project website: https://cifra-c2unesco.ro/projects/investigations-of-beyond-standard-model-physics-from-theoretical-studies-of-double-beta-decay/

Abstract:

This project aims to do relevant steps forward in the theoretical study of double-beta decay (DBD). This process is of great interest since it can provide information about the validity of some laws as lepton number conservation, CP and Lorentz invariance (LI) and about the properties of neutrinos (Dirac or Majorana particles?, absolute mass, hierarchy and mechanism of generation, no. neutrino species). These are related to the discovery of the so-called neutrinoless DBD (0νββ) mode which is currently searched experimentally. Accurate predictions of the half-lives, electron spectra, models for mechanisms mediating 0νββ decay, are all necessary and can save significant experimental costs. The general objective of the project is to provide accurate calculations of the nuclear matrix elements (NME), phase-space factors (PSF) and other kinematic factors that will be used to investigate neutrino properties, beyond standard model (BSM) phenomena and LI violation. Specific objectives are: a) obtaining of improved formulas for DBD rates by including new contributions; b) implementation these formulas in the numerical codes for NME and PSF calculation by building up of new routines; c) computations of NMEs and PSFs for (2ν,0ν)ββ transitions and derivation of new limits for the BSM parameters; d) investigation of LI violation in DBD; e) determining the gA value, etc. The results will be published in several ISI ranked journals and presented in relevant conferences. We expect our projec

Contributions to the study of double-beta decay and investigation of physics beyond the Standard Model Call name: P 4 - Proiecte de Cercetare Exploratorie, 2020
PN-III-P4-ID-PCE-2020-2374 2021 - 2023

Role in this project:

Coordinating institution: CENTRUL INTERNAŢIONAL PENTRU PREGĂTIRE AVANSATĂ ŞI CERCETARE ÎN FIZICĂ-FILIALĂ A INCDFM BUCUREŞTI

Project partners: CENTRUL INTERNAŢIONAL PENTRU PREGĂTIRE AVANSATĂ ŞI CERCETARE ÎN FIZICĂ-FILIALĂ A INCDFM BUCUREŞTI (RO)

Affiliation:

Project website: https://cifra-c2unesco.ro/projects/contributions-to-the-study-of-double-beta-decay-and-investigation-of-physics-beyond-the-standard-model/

Abstract:

Double-beta decay (DBD) is the rarest spontaneous nuclear decay process experimentally observed until now with half-lives of the order of 10^20 years. It has a broad potential of discovery mainly due to the search of the decay mode without emission of neutrinos 0νββ decay. Its discovery would provide us with key information about i) neutrino properties (neutrino character: Dirac or Majorana particle and hints about its absolute mass, mass hierarchy, neutrino flavors, existence of sterile neutrinos, etc.), ii) mechanisms which can contribute to 0νββ (such as: exchange of light/heavy neutrinos, exchange of SUSY particles, Majoron emission, contribution from RH currents from the weak interaction, etc.) and iii) on the validity of some conservation laws (lepton number, CP violation, Lorentz invariance, etc.). All these issues are related to physics beyond the SM. In this project we aim to bring significant contributions in the DBD study by doing advances in all parts of the DBD half-lives: the calculation of the phase space factors and nuclear matrix elements, and investigation of beyond SM phenomena as constraints of LNV parameters, Lorentz invariance violation in the neutrino sector, and other related issues.

Neutrino properties derived from the study of rare decay processes at low and high energies Call name: P 4 - Proiecte de Cercetare Exploratorie
PN-III-P4-ID-PCE-2016-0078 2017 - 2019

Role in this project: Key expert

Coordinating institution: CENTRUL INTERNAŢIONAL PENTRU PREGĂTIRE AVANSATĂ ŞI CERCETARE ÎN FIZICĂ-FILIALĂ A INCDFM BUCUREŞTI

Project partners: CENTRUL INTERNAŢIONAL PENTRU PREGĂTIRE AVANSATĂ ŞI CERCETARE ÎN FIZICĂ-FILIALĂ A INCDFM BUCUREŞTI (RO)

Affiliation: CENTRUL INTERNAŢIONAL PENTRU PREGĂTIRE AVANSATĂ ŞI CERCETARE ÎN FIZICĂ-FILIALĂ A INCDFM BUCUREŞTI (RO)

Project website: http://cifra.infim.ro/PN-III-P4-ID-PCE-2016-0078.php

Abstract:

Investigation of neutrino properties represents a priority topic of research in physics, from which one expects important results in the next future. This project proposes itself a theoretical study of the neutrino properties by combining the results obtained from the investigation of the 0νββ decay (low-energy process) with results provided by the analysis of several LNV decay channels (high energy processes) within the LHCb experiment. Firstly, we propose ourselves to develop a novel, approach to calculate accurately the phase space factors (F0ν) and nuclear matrix elements (M0ν), two key quantities entering the lifetime formulas, that were computed separately until now in literature. Their computation will be performed in a unitary manner, by deriving a unique formula for their product, and then building a new numerical code where the same nuclear approximations and input parameters be used consistently, for both quantities. In order to eliminate errors associated with large uncertainties of some quantities involved in calculations, we combine our theoretical calculations with experimental results taken from different 0νββ decay experiments. In this way we aim to significantly reduce the uncertainties in the F0ν and M0ν calculation and bring an important achievement in the domain. Then, we derive reliable neutrino parameters and constrain different BSM decay mechanisms. Further, we use information on neutrinos derived from the 0νββ decay and from other low-energy processes, to investigate several rare decays channels of hyperons at high energy, to predict Br bounds and constrain other BSM parameters. These channels can analized within the LHCb experiment at CERN. Such a complementary analysis it is not yet done, and represents another important novel ingredient of the project.

OPEN PROBLEMS IN RADIOLOGICAL IMPACT ASSESSMENT OF TRITIUM EMISSIONS INCLUDING CLIMATE CHANGE Call name: P 4 - Proiecte de Cercetare Exploratorie
PN-III-P4-ID-PCE-2016-0218 2017 - 2019

Role in this project: Key expert

Coordinating institution: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA SI INGINERIE NUCLEARA " HORIA HULUBEI " - IFIN - HH

Project partners: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA SI INGINERIE NUCLEARA " HORIA HULUBEI " - IFIN - HH (RO)

Affiliation: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA SI INGINERIE NUCLEARA " HORIA HULUBEI " - IFIN - HH (RO)

Project website: http://proiecte.nipne.ro/pn3/5-projects.html

Abstract:

In order to prove the enhanced safety and reduced costs, nuclear energy needs robust radiological impact assessment models. In Romania, developing CANDU technology, tritium is the main radioactive pollutant. Once emitted as tritiated water (HTO), tritium enters the life cycle and is transformed in plants in exchangeable and non-exchangeable organically bound tritium (E-OBT and NE-OBT). The residence time of NE-OBT in plants and animals is longer and the health impact (radiological dose) is higher than that of HTO and E-OBT. For normal operation of the nuclear facilities, the present models under estimate the tritium concentration in plants comparing with the experimental results. For short term and intense emissions (incidents) the present dynamic models have an unacceptable large range of predictions for tritium concentration in plants. Similar processes for tritium transfer in environment are involved in both situations (normal operation and incidents), but for OBT formation in crops some processes are still not yet well understood, mostly at night. A novel conceptual model for OBT production at day and night was recently developed by IFIN-HH researchers. The project objective is to develop a new model for practical application in radiological risk assessment, considering the detailed dynamics of tritiated compounds formed in photosynthesis and the subsequent biochemical reactions at various time steps during the development period of crops. The modelling of HTO concentration dynamics in leaves will be improved considering the balance between air and root pathways and the role of stomata conductance. The project will consider the main crops in Cernavoda area, considering the effects of climate change on HTO and OBT concentration in crops at harvest. The project will also consider the biota radioprotection as it was recently required by EC and will use concepts of animal adaptation to environment and the available data on carbon and caesium dynamics in biota.

Development of models and methods for computation of the nuclear matrix elements involved in the study of double-beta decay Call name: Exploratory Research Projects - PCE-2011 call
PN-II-ID-PCE-2011-3-0318 2012 - 2016

Role in this project: Key expert

Coordinating institution: Fundatia Horia Hulubei

Project partners: Fundatia Horia Hulubei (RO)

Affiliation: Fundatia Horia Hulubei (RO)

Project website: http://www.infim.ro/hhf/projects.html

Abstract:

The project proposes to develop new nuclear structure models and high performance computing codes based on the Shell Model to provide a reliable description of the nuclear matrix elements (NMEs) involved in the double-beta (ββ) decays. The NMEs are essential to improve the knowledge of the absolute neutrino masses, and to investigate the possibility of determining the leading mechanisms for the neutrinoless double beta (0νββ) decay mode. The specific ojectives of this project include: i)establish reliable effective shell model NN interactions that can adequately reproduce the spectroscopic properties of the nuclei in the mass-regions of the main ββ decay emitters; ii)develop an efficient code to calculate the two-body matrix elements of the 0νββ-decay operator, including high orders effects in the nucleon currents, short-range correlations and other nucleon-dressing effects; iii)estimate the effects of enlarging the size of the shell model spaces that may break general symmetries; iv)predict new limits and uncertainties for the effective 0νββ neutrino mass assuming a standard 0νββ decay half-life of 10^26 years; v)derive explicit expressions for the transition amplitudes of other possible 0νββ decay mechanisms and investigate strength of their contributions; vi) disseminate the results to the experimentalists, which are using theoretical NMEs in the planning of their ββ decay experiments.

STRONG DISSIPATIVE REGIME IN THE QUANTUM MECHANICS OF NUCLEAR REACTIONS Call name: Exploratory Research Projects - PCE-2011 call
PN-II-ID-PCE-2011-3-0068 2012 - 2016

Role in this project: Key expert

Coordinating institution: INSTITUTUL NATIONAL DE CERCETARE DEZVOLTARE PENTRU FIZICA SI INGINERIE NUCLEARA HORIA HULUBEI

Project partners: INSTITUTUL NATIONAL DE CERCETARE DEZVOLTARE PENTRU FIZICA SI INGINERIE NUCLEARA HORIA HULUBEI (RO)

Affiliation: INSTITUTUL NATIONAL DE CERCETARE DEZVOLTARE PENTRU FIZICA SI INGINERIE NUCLEARA HORIA HULUBEI (RO)

Project website: http://www.theory.nipne.ro/~mirea

Abstract:

WE WILL FOCUSS ON A STRONG DISSIPATIVE REGIME BY DEVELOPING QUANTUM MODEL WITH APPLICATION IN NUCLEAR PHYISCS. NEW METHODS FOR THE TREATMENT OF NUCLEAR REACTIONS WILL BE DEVELOPED BY CALCULATING THE DEFORMATION ENERGY SURFACE IN THE CONFIGURATION SPACE, TOGETHER WITH THE EFFECTIVE MASS OF THE SYSTEM AND THE DISSIPATION ENERGY. DYNAMICAL METHODS THAT ARE BAZED ON THE MINIMAL ACTION FUNCTIONAL PRIME PRINCIPLE OR THE SOLUTIONS OF THE EULER-LAGRANGE EQUATIONS WILL BE USED. THE OPTIMUM PATH IN THE CONFIGURATION SPACE FOR SERVGERAL TYPES OF NUCLEAR REACTIONS WILL BE DEDUCED, NEW APPROACHES WILL BE DEVELOPED FOR STRONG DISSIPATIVE REGIMES AND A SMALL NUMBER OF CONSTITUENT PARTICLE,

Interdisciplinary approach for dynamic modelling of tritium transfer in crops Call name: Exploratory Research Projects - PCE-2011 call
PN-II-ID-PCE-2011-3-0396 2011 - 2016

Role in this project: Key expert

Coordinating institution: Institutul National de Fizica si Inginerie Nucleara "Horia Hulubei"

Project partners: Institutul National de Fizica si Inginerie Nucleara "Horia Hulubei" (RO)

Affiliation: Institutul National de Fizica si Inginerie Nucleara "Horia Hulubei" (RO)

Project website: http://proiecte.nipne.ro/pn2/142-proiecte.html

Abstract:

Romania develops nuclear energy using CANDU 6 (CANadian Deuterium Uranium) reactors, which have a high tritium load. Tritium, once in the environment, is very mobile and can be effectively incorporated into the biological systems. It is well known that the tritium modelling is different than that for the other contaminants. Nowadays, it is obvious that the nuclear safety must be enhanced in each country, following the recent request from European Community (EC), International Committee for Radiological Protection (ICRP) and International Atomic Energy Agency (IAEA). IFIN-HH is internationally recognized for its experience in tritium modelling and leads a working group dedicated to “Tritium” Accidents in the frame of IAEA Environmental Modelling for Radiation Safety (EMRAS) programme.

The project proposes the development of an interdisciplinary, physical-mathematical, biochemical and physiological model of the dynamic interactions between tritium (as HTO) in atmosphere and soil (from where tritium once emitted, enters straight into the life cycle) and biosphere - crops (and animals), using the recent results from the life sciences, radioecology, and agricultural research, together with the associated data base and computer codes. The intention is to keep an optimal ratio between the complexity of the modelled processes and the limits of the practical knowledge, with a reliable predictive power in order to be applied in practice.

FILE DESCRIPTION	DOCUMENT
List of research grants as project coordinator or partner team leader
Significant R&D projects for enterprises, as project manager
R&D activities in enterprises
Peer-review activity for international programs/projects