INGLESE

Lo studente acquisirà familiarità e conoscenza con argomenti concernenti i) le principali nozioni riguardanti gli isotopi stabili e radioattivi; ii) i fenomeni che caratterizzano la loro variabilità ambientale; iii) le metodologie fisiche di misura.

Environmental isotopes in the hydrological cycle. Principles and Applications. VOLUME 1.
International Atomic Energy Agency
and United Nations Educational, Scientific and Cultural Organization. Freely available @ http://www-naweb.iaea.org/napc/ih/documents/global_cycle/Environmental%20Isotopes%20in%20the%20Hydrological%20Cycle%20Vol%201.pdf

Conoscenza e capacità di comprensione dei principali fenomeni legati all’applicazione della fisica alla ricerca isotopica.

Conoscenza delle basi di Fisica Nucleare (utile); Conoscenza dei principi di Elettromagnetismo (importante).

Lezioni frontali ed esercitazioni numeriche per un totale di (6x8) 48 ore

Le modalità di verifica dell’apprendimento comprendono: una parte scritta (redazione di report con discussine approfondita dei risultati) concorrente al 100% (per i frequentanti) della valutazione finale.

PROGRAM
1. ATOMIC SYSTEMATICS AND NUCLEAR STRUCTURE
1.1. Atomic structure and the periodic table of the elements
1.2. Structure of the atomic nucleus
1.3. Stable and radioactive isotopes
1.4. Mass and energy
2. RADIONUCLIDE DECAY AND PRODUCTION
2.1. Nuclear instability
2.2. Nuclear decay and radiation
2.2.1. Negatron (β−) decay
2.2.2. Positron (β+) decay
2.2.3. Electron capture (EC)
2.2.4. Alpha () decay
2.2.5. Spontaneous and induced fission, neutron emission
2.3. Recoil by radioactive decay
2.4. Nuclear reactions
2.4.1. Natural production
2.4.2. Anthropogenic releases of radionuclides
3. EQUATIONS OF RADIOACTIVE DECAY AND GROWTH
3.1. Law of radioactive decay
3.2. Half-life and mean life
3.3. Activity, specific activity and radionuclide concentration
3.4. Mixture of independent radioactivities
3.5. Branching decay
3.6. Radioactive decay series
3.6.1. Secular equilibrium
3.6.2. Transient equilibrium
3.6.3. No-equilibrium
3.7. Accumulation of stable daughter product
3.8. Radioactive growth
3.9. Decay series
3.10. The uranium series
3.10.1. 238U/234U
3.10.2. 230Th 234U dating
3.10.3. 226Ra and 222Rn
3.10.4. 210Pb
3.10.5. Experimental and technical aspects
3.10.6. The actinium series
3.10.7. The Thorium series
4. ABUNDANCE AND FRACTIONATION OF STABLE ISOTOPES
4.1. Isotope ratios and concentrations
4.2. Isotope fractionation
4.3. Kinetic and equilibrium isotope fractionation
4.4. Theoretical background of equilibrium fractionation
4.5. Fractionation by diffusion
4.6. Relation between atomic and molecular isotope ratios
4.7. Relation between fractionations for three isotopic molecules
5. ABUNDANCE VARIATIONS BY NATURAL PROCESSES
5.1. Use of δ values and isotope references
5.2. Tracer concentration, amount of tracer
5.3. Mixing of reservoirs with different isotopic composition
5.3.1. Mixing of reservoirs of the same compound
5.3.1.1. Isotopic dilution analysis
5.3.2. Mixing of reservoirs of different compounds
5.4. Isotopic changes in Rayleigh processes
5.4.1. Reservoir with one sink
5.4.2. Reservoir with two sinks
5.4.3. Reservoir with one source and one sink, as a function of time
5.4.4. Reservoir with one source and one sink, s a function of mass
5.4.5. Reservoir with two sources and two sinks, with and without fractionation
6. NATURAL ABUNDANCE OF THE STABLE ISOTOPES OF C AND O
6.1. Stable carbon isotopes
6.1.1. The natural abundance
6.1.2. Carbon isotope fractionations
6.1.3. Reporting 13C variations and the 13C standard
6.1.4. Survey of natural 13C variations
6.1.4.1. Atmospheric CO2
6.1.4.2. Seawater and marine carbonate
6.1.4.3. Vegetation and soil CO2
6.1.4.4. Fossil fuel
6.1.4.5. Global carbon cycle
6.1.4.6. Groundwater and riverwater
6.2. Stable oxygen isotopes
6.2.1. The natural abundance
6.2.2. Oxygen isotope fractionations
6.2.3. Reporting 18O variations and the 18O standards
6.2.4. Survey of natural 18O variations
6.2.4.1. Seawater
6.2.4.2. Precipitation
6.2.4.3. Surface water
6.2.5. Climatic variations
7. NATURAL ABUNDANCE OF RADIOACTIVE ISOTOPES OF C
7.1. The radioactive carbon isotope
7.1.1. Origin of 14C, decay and half-life
7.1.2. Reporting 14C variations and the 14C standard
7.1.3. Survey of natural 14C variations
7.1.3.1. Atmospheric CO2
7.1.3.2. Vegetation and soils
7.1.3.3. Seawater and marine carbonate
7.1.3.4. Groundwater
7.1.4. 14C age determination
7.1.5. Dating groundwater
7.1.5.1. Dating groundwater with DIC
7.1.5.2. Dating groundwater with DOC
7.2. Relation between 13C and 14C variations
8. MEASURING TECHNIQUES
8.1. Mass spectrometry for stable isotopes
8.1.1. Physical principle
8.1.2. Reporting stable isotope Abundance ratios
8.1.3. Measurement of 13C/12C and 18O/16O in CO2
8.1.3.1. Comparison with machine reference
8.1.4. Calibration
8.1.4.1. Isotopic corrections
8.1.4.2. Normalisation
8.2. Radiometry for radioactive isotopes
8.2.1. Gas counters
8.2.1.1. Ionisation chamber
8.2.1.2. Proportional counter
8.2.1.3. Geiger Müller counter
8.2.1.4. Counter operation
8.3. Mass spectrometry for low-abundance isotopes
8.3.1. Principle and application of AMS
8.4. Reporting 14C activities and concentrations
8.4.1. The choice of variables
8.4.2. The standardisation
8.4.2.1. The question of isotope fractionation
8.4.2.2. The question of radioactive decay
8.4.2.3. Definition of the 14C standard activity
8.4.3. Final definitions

English

The student will acquire familiarity and knowledge of topics concerning i) the main notions concerning stable and radioactive isotopes; ii) the phenomena characterizing their environmental variability; iii) physical measurement methods.

Environmental isotopes in the hydrological cycle. Principles and Applications. VOLUME 1.
International Atomic Energy Agency
and United Nations Educational, Scientific and Cultural Organization. Freely available @ http://www-naweb.iaea.org/napc/ih/documents/global_cycle/Environmental%20Isotopes%20in%20the%20Hydrological%20Cycle%20Vol%201.pdf

Knowledge and understanding of the main phenomena related to the application of physics to isotope research.

Knowledge of the basics of Nuclear Physics (useful); Knowledge of the principles of electromagnetism (important).

Frontal Classes and numerical exercizes for a total of (6x8) 48 hours

Methods for learning verification: Report production for the attendees that competes with 100% of the final assessment.

PROGRAM
1. ATOMIC SYSTEMATICS AND NUCLEAR STRUCTURE
1.1. Atomic structure and the periodic table of the elements
1.2. Structure of the atomic nucleus
1.3. Stable and radioactive isotopes
1.4. Mass and energy
2. RADIONUCLIDE DECAY AND PRODUCTION
2.1. Nuclear instability
2.2. Nuclear decay and radiation
2.2.1. Negatron (β−) decay
2.2.2. Positron (β+) decay
2.2.3. Electron capture (EC)
2.2.4. Alpha () decay
2.2.5. Spontaneous and induced fission, neutron emission
2.3. Recoil by radioactive decay
2.4. Nuclear reactions
2.4.1. Natural production
2.4.2. Anthropogenic releases of radionuclides
3. EQUATIONS OF RADIOACTIVE DECAY AND GROWTH
3.1. Law of radioactive decay
3.2. Half-life and mean life
3.3. Activity, specific activity and radionuclide concentration
3.4. Mixture of independent radioactivities
3.5. Branching decay
3.6. Radioactive decay series
3.6.1. Secular equilibrium
3.6.2. Transient equilibrium
3.6.3. No-equilibrium
3.7. Accumulation of stable daughter product
3.8. Radioactive growth
3.9. Decay series
3.10. The uranium series
3.10.1. 238U/234U
3.10.2. 230Th 234U dating
3.10.3. 226Ra and 222Rn
3.10.4. 210Pb
3.10.5. Experimental and technical aspects
3.10.6. The actinium series
3.10.7. The Thorium series
4. ABUNDANCE AND FRACTIONATION OF STABLE ISOTOPES
4.1. Isotope ratios and concentrations
4.2. Isotope fractionation
4.3. Kinetic and equilibrium isotope fractionation
4.4. Theoretical background of equilibrium fractionation
4.5. Fractionation by diffusion
4.6. Relation between atomic and molecular isotope ratios
4.7. Relation between fractionations for three isotopic molecules
5. ABUNDANCE VARIATIONS BY NATURAL PROCESSES
5.1. Use of δ values and isotope references
5.2. Tracer concentration, amount of tracer
5.3. Mixing of reservoirs with different isotopic composition
5.3.1. Mixing of reservoirs of the same compound
5.3.1.1. Isotopic dilution analysis
5.3.2. Mixing of reservoirs of different compounds
5.4. Isotopic changes in Rayleigh processes
5.4.1. Reservoir with one sink
5.4.2. Reservoir with two sinks
5.4.3. Reservoir with one source and one sink, as a function of time
5.4.4. Reservoir with one source and one sink, s a function of mass
5.4.5. Reservoir with two sources and two sinks, with and without fractionation
6. NATURAL ABUNDANCE OF THE STABLE ISOTOPES OF C AND O
6.1. Stable carbon isotopes
6.1.1. The natural abundance
6.1.2. Carbon isotope fractionations
6.1.3. Reporting 13C variations and the 13C standard
6.1.4. Survey of natural 13C variations
6.1.4.1. Atmospheric CO2
6.1.4.2. Seawater and marine carbonate
6.1.4.3. Vegetation and soil CO2
6.1.4.4. Fossil fuel
6.1.4.5. Global carbon cycle
6.1.4.6. Groundwater and riverwater
6.2. Stable oxygen isotopes
6.2.1. The natural abundance
6.2.2. Oxygen isotope fractionations
6.2.3. Reporting 18O variations and the 18O standards
6.2.4. Survey of natural 18O variations
6.2.4.1. Seawater
6.2.4.2. Precipitation
6.2.4.3. Surface water
6.2.5. Climatic variations
7. NATURAL ABUNDANCE OF RADIOACTIVE ISOTOPES OF C
7.1. The radioactive carbon isotope
7.1.1. Origin of 14C, decay and half-life
7.1.2. Reporting 14C variations and the 14C standard
7.1.3. Survey of natural 14C variations
7.1.3.1. Atmospheric CO2
7.1.3.2. Vegetation and soils
7.1.3.3. Seawater and marine carbonate
7.1.3.4. Groundwater
7.1.4. 14C age determination
7.1.5. Dating groundwater
7.1.5.1. Dating groundwater with DIC
7.1.5.2. Dating groundwater with DOC
7.2. Relation between 13C and 14C variations
8. MEASURING TECHNIQUES
8.1. Mass spectrometry for stable isotopes
8.1.1. Physical principle
8.1.2. Reporting stable isotope Abundance ratios
8.1.3. Measurement of 13C/12C and 18O/16O in CO2
8.1.3.1. Comparison with machine reference
8.1.4. Calibration
8.1.4.1. Isotopic corrections
8.1.4.2. Normalisation
8.2. Radiometry for radioactive isotopes
8.2.1. Gas counters
8.2.1.1. Ionisation chamber
8.2.1.2. Proportional counter
8.2.1.3. Geiger Müller counter
8.2.1.4. Counter operation
8.3. Mass spectrometry for low-abundance isotopes
8.3.1. Principle and application of AMS
8.4. Reporting 14C activities and concentrations
8.4.1. The choice of variables
8.4.2. The standardisation
8.4.2.1. The question of isotope fractionation
8.4.2.2. The question of radioactive decay
8.4.2.3. Definition of the 14C standard activity
8.4.3. Final definitions