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Nuclear Data Sheets for A = 61

The evaluated spectroscopic data are presented for known nuclides of mass 61 (Sc,Ti,V,Cr,Mn,Fe,Co,Ni, Cu,Zn,Ga,Ge). Excited-state data are nonexistent for {sup 61}Sc, {sup 61}Ti, {sup 61}V, and {sup 61}Ge. Significant amounts of new data have been added since the previous NDS evaluation of A=61 nuclides (1999Bh04). {sup 61}Sc nuclide is now experimentally known, but without any knowledge of its half-life. The ground state half-lives of {sup 61}Ti and {sup 61}V are now determined. Excited-state data have become available for {sup 61}Cr, {sup 61}Mn and {sup 61}Ga, while for {sup 61}Ge, five excited states were erroneously assigned in the previous evaluation, these have been omitted here. Improved and extensive high-spin excitations are available for {sup 61}Fe, {sup 61}Cu and {sup 61}Zn, including several new superdeformed structures in {sup 61}Cu and {sup 61}Zn. Thermal neutron capture γ-ray data are available in detail from 2004Ra23. The radioactive decay schemes of {sup 61}Sc and {sup 61}Ti are not known, while those for {sup 61}V, {sup 61}Fe and {sup 61}Ge are poorly known. This work benefited from the earlier full evaluations of A=61 published by 1999Bh04, 1983Ek01 and 1975Au05 and the one published in an ‘update’ mode by 1992Zh31. The data and conclusions presented in the current work supersede those in all the previous evaluations.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Primary and secondary battery consumption trends in Sweden 1996–2013: Method development and detailed accounting by battery type

Highlights: • Developed MFA method was validated by the national statistics. • Exponential increase of EEE sales leads to increase in integrated battery consumption. • Digital convergence is likely to be a cause for primary batteries consumption decline. • Factors for estimation of integrated batteries in EE are provided. • Sweden reached the collection rates defined by European Union. - Abstract: In this article, a new method based on Material Flow Accounting is proposed to study detailed material flows in battery consumption that can be replicated for other countries. The method uses regularly available statistics on import, industrial production and export of batteries and battery-containing electric and electronic equipment (EEE). To promote method use by other scholars with no access to such data, several empirically results and their trends over time, for different types of batteries occurrence among the EEE types are provided. The information provided by the method can be used to: identify drivers of battery consumption; study the dynamic behavior of battery flows – due to technology development, policies, consumers behavior and infrastructures. The method is exemplified by the study of battery flows in Sweden for years 1996–2013. The batteries were accounted, both in units and weight, as primary and secondary batteries; loose and integrated; by electrochemical composition and share of battery use between different types of EEE. Results show that, despite a fivefold increase in the consumption of rechargeable batteries, they account for only about 14% of total use of portable batteries. Recent increase in digital convergence has resulted in a sharp decline in the consumption of primary batteries, which has now stabilized at a fairly low level. Conversely, the consumption of integrated batteries has increased sharply. In 2013, 61% of the total weight of batteries sold in Sweden was collected, and for the particular case of alkaline manganese dioxide batteries, the value achieved 74%.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Invited Article: In situ comparison of passive radon-thoron discriminative monitors at subsurface workplaces in Hungary

During a one-year long measurement period, radon and thoron data obtained by two different passive radon-thoron discriminative monitors were compared at subsurface workplaces in Hungary, such as mines (bauxite and manganese ore) and caves (medical and touristic). These workplaces have special environmental conditions, such as, stable and high relative humidity (100%), relatively stable temperature (12°C–21°C), low or high wind speed (max. 2.4 m s{sup −1}) and low or elevated aerosol concentration (130–60 000 particles m{sup −3}). The measured radon and thoron concentrations fluctuated in a wide range among the different workplaces. The respective annual average radon concentrations and their standard deviations (in brackets) measured by the passive radon-thoron discriminative monitor with cellulose filter (CF) and the passive radon-thoron discriminative monitor with sponge filter (SF) were: 350(321) Bq m{sup −3} and 550(497) Bq m{sup −3} in the bauxite mine; 887(604) Bq m{sup −3} and 1258(788) Bq m{sup −3} in the manganese ore mine; 2510(2341) Bq m{sup −3} and 3403(3075) Bq m{sup −3} in the medical cave (Hospital Cave of Tapolca); and 6239(2057) Bq m{sup −3} and 8512(1955) Bq m{sup −3} in the touristic cave (Lake Cave of Tapolca). The respective average thoron concentrations and their standard deviation (in brackets) measured by CF and SF monitors were: 154(210) Bq m{sup −3} and 161(148) Bq m{sup −3} in the bauxite mine; 187(191) Bq m{sup −3} and 117(147) Bq m{sup −3} in the manganese-ore mine; 360(524) Bq m{sup −3} and 371(789) Bq m{sup −3} in the medical cave (Hospital Cave of Tapolca); and 1420(1184) Bq m{sup −3} and 1462(3655) Bq m{sup −3} in the touristic cave (Lake Cave of Tapolca). Under these circumstances, comparison of the radon data for the SF and CF monitors showed the former were consistently 51% higher in the bauxite mine, 38% higher in the manganese ore mine, and 34% higher in the caves. Consequently, correction is required on previously obtained radon data acquired by CF monitors at subsurface workplaces to gain comparable data for SF monitors. In the case of thoron, the data were unreliable and no significant tendency was seen during the comparison therefore comparison of previously obtained thoron data acquired by either CF or SF is doubtful. There was probable influence by relative humidity on the detection response; however, the effects of the high wind speed and elevated aerosol concentration could not be excluded. The results of this study call attention to the importance of calibration under extreme environmental conditions and the need for using reliable radon-thoron monitors for subsurface workplaces.

54 ENVIRONMENTAL SCIENCES↗

TU-F-CAMPUS-T-01: Dose and Energy Spectra From Neutron Induced Radioactivity in Medical Linear Accelerators Following High Energy Total Body Irradiation

Purpose: To assess the risk posed by neutron induced activation of components in medical linear accelerators (linacs) following the delivery of high monitor unit 18 MV photon beams such as used in TBI. Methods: Gamma spectroscopy was used to identify radioisotopes produced in components of a Varian 21EX and an Elekta Synergy following delivery of photon beams. Dose and risk estimates for TBI were assessed using dose deliveries from an actual patient treatment. A 1 litre spherical ion chamber (PTW, Germany) has been used to measure the dose at the beam exit window and at the total body irradiation (TBI) treatment couch following large and small field beams with long beam-on times. Measurements were also made outside of the closed jaws to quantify the benefit of the attenuation provided by the jaws. Results: The radioisotopes produced in the linac head have been identified as {sup 187}W, {sup 56}Mn, {sup 24}Na and {sup 28}Al, which have half-lives from between 2.3 min to 24 hours. The dose at the beam exit window following an 18 MV 2197 MU TBI beam delivery was 12.6 µSv in ten minutes. The dose rate at the TBI treatment couch 4.8 m away is a factor of ten lower. For a typical TBI delivered in six fractions each consisting of four beams and an annual patient load of 24, the annual dose estimate for a staff member at the treatment couch for ten minutes is 750 µSv. This can be further reduced by a factor of about twelve if the jaws are closed before entering the room, resulting in a dose estimate of 65 µSv. Conclusion: The dose resulting from the activation products for a representative TBI workload at our clinic of 24 patients per year is 750 µSv, which can be further reduced to 65 µSv by closing the jaws.

61 RADIATION PROTECTION AND DOSIMETRY↗

SU-E-T-534: Level of Residual Radioactivity of Activated Parts of a Decommissioned Cyclotron

Purpose: CTI cyclotron RDS-111 was used at the Hong Kong Sanatorium and Hospital (HKSH) to produce radiopharmaceuticals and radioactive tracers for diagnostic scans between 1999 and 2007. During the operation, some machine components became radioactive by activation. For the safety of staff, decommissioning took place in 2009, two years after the cyclotron had stopped operation. This study investigates the residual radioactivity and radionuclides found in different cyclotron components in 2014 in compliance with the local regulations in Hong Kong for transfer of radioactive waste. Methods: A representative sample of each part was counted using a high-purity germanium detector (manufacturer: ORTECT) for at least four hours. GammaVision, a multichannel analyzer software, was used to identify the radionuclides found in the cyclotron components, as well as the associated activities. A standard library and a Mariscotti peak search algorithm were used to identify the present radionuclides. Only radionuclides with half-life greater than 180 days were considered. Results: Among the components, the Havar target foil has the highest specific activity ((4.6±0.6)×10{sup 2} Bq/g), with Co-60 being the most prominent ((3.8±0.5)×10{sup 2} Bq/g). The total activity of the target foil, however, is still low due to its small mass of 0.04 g. Radioisotopes Mn-54 (46±6 Bq/g), Na-22 (6.8±0.8 Bq/g), Co-57 (7.3±0.9 Bq/g), and Fe-59 (6.0±0.9 Bq/g) have also been detected in the target foil. The target window holder and the vacuum window register a specific activity of 88.3±0.6 Bq/g and 48.6±0.1 Bq/g, respectively. Other components, such as the collimator, the target tube, the valve body and the beamline, are also found with trace amounts of radionuclides. Conclusion: Even seven years after the cyclotron had stopped operation, some components still exhibited residual radioactivity from activation exceeding the IAEA clearance levels. Special consideration for radiological protection may need to be taken in the disposal of the cyclotron parts.

07 ISOTOPE AND RADIATION SOURCES↗

SU-E-T-612: Photonuclear Activation of Prosthetic Hips in Radiotherapy

Purpose: To measure the neutron induced activation of a prosthetic hip when exposed to an 18 MV radiotherapy linac beam to assess the potential dose to patients. Methods: A prosthetic hip (Thackray, UK) was placed in a water phantom and irradiated (both in-field and out-of-field) with an 18 MV linac beam. Gamma spectroscopy was used to identify the radioisotopes produced. Following the in-field irradiation where the induced activity is higher, high sensitivity lithium fluoride Thermoluminescence Dosimeters (TLD-100H) (Harshaw, USA) were placed on the surface to measure the dose which would be deposited to nearby tissue resulting from the induced radioactivity. Results: The radioisotopes produced in the hip prosthesis have been identified as {sup 5{sup 2}}V, {sup 5{sup 3}}Fe, and {sup 56}Mn which have half-lives of 3.74, 8.51 and minutes respectively. The 378 and 511 keV characteristic peaks of {sup 5{sup 3}}Fe do not appear in the spectra collected from hips irradiated in the out-of-field region. This isotope is produced by photonuclear interactions within the hip itself. {sup 52}V and {sup 56}Mn appear in spectra collected from hips irradiated either within the photon beam or in the nearby out-of-field region, implying that they are produced by incident neutron radiation produced in components of the linear accelerator.The integrated dose which would be deposited in the tissue immediately surrounding the hip after four hours (1.5 half-lives of the longest lived product) was measured as approximately 100 µGy, following a 10,000 MU irradiation of the prosthesis. A highly accurate measurement of the dose is challenging because of the irregular shape of the prosthesis. Conclusion: The cumulative dose measured at the surface of the hip is 0.0001% of the in-field dose, and is therefore negligible compared with the doses the patient receives as a consequence of their treatment.

61 RADIATION PROTECTION AND DOSIMETRY↗

Study of Plastic Scintillator Properties for Radioactive Sources Dosimetry - Paper 108

Plastic scintillator is a simple material which has the density close to that of human soft tissue (1.06 g/cm{sup 3}). Its energy response is close to that of human soft tissue and it is relatively energy independent. This prospect provide a desired characteristics in measuring dose by plastic scintillator either for radiation monitoring or personal dosimeter. Generally the energy calibration of organic scintillator will be done by using gamma ray sources. The positions of Compton edge in pulse height spectra, which have known energy values will be identified. However the Compton edge normally is very broad and difficult to determine the point corresponding to that particular Compton electron energies. Many researchers used several fitting functions and Monte Carlo simulations to determine the position of Compton edge. For example, Proctor and Wellman (2012) used a straight line fit to the linear part of Compton edge and extrapolated to zero count. While L. Swiderski et al. used a method based on a back-scattered coincidence measurement to measure in a wide energy range the position of Compton edge in organic scintillators. For a simple and quick approach of calibration, we used a Gauss-error function to fit the Compton edge region of interest by assumed that the location of maximum energy of Compton electrons is half-height of the Compton maximum (CM). The reasons is because the CM position could be determined easily from the spectra throughout wide energy range. Interpreting gamma dose rates from accumulated plastic scintillation detector spectra is often a complex task because the probability of a full energy deposition event in the detector is often negligible. Despite no full energy peaks in plastic scintillator spectra, several attempts have been made by the other researchers to obtain the dose from the energy distribution spectra of gamma radiation. For example, Proctor and Wellman used the modified spectrum dose index (SDI) to calculate the exposure rates by multiplying the energy corresponding to its channel and all products are summed before multiply by a calibration constant to yield an exposure rate. While Lobdell and Hertel calculated dose using a response matrix based on spectral unfolding technique. From these points of view, we have made an attempt to correlate the counts obtained in scintillator with absorbed dose or ambient dose equivalent. We aimed to calibrate the plastic scintillator energy deposition for dose, by correlate the counts obtained with a particular value of dose. By designed the scintillator to measure at 1 cm tissue depth might be helpful to be used as radiation monitoring or personal dosimeter since the energy response of plastic scintillator is relatively energy independent compared to that of inorganic scintillators. The energy calibration proposed from simple fitting approach had been verified with calculated spectra. This might be considered as a practical approach for technician or radiation workers with sufficient accuracy. The linear behavior of counts per absorbed dose give promising to calibrate scintillator energy deposition to read dose (equivalent dose or absorbed dose) for photons. Thus the scintillator could provide both the energy and dose response simultaneously, which may important in some radiation field of measurements. Currently the scintillator is able to give dose rate value for gamma sources of Cs-137 and Mn-54. The number of counts per unit absorbed dose would likely to vary somewhat with photon energy, although the plastic scintillator should have a tissue dose response that is relatively energy independent. Further analysis will be done on conversion factor parameters so that it could be used in such situations where the radiation field is complex or unknown. (authors)

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Calculations of the Structural, Elastic, Magnetic, and Electronic Properties of the New Compound BaZr{sub 0.5}Mn{sub 0.5}O{sub 3} with Tetragonal Structure

Based on the density functional theory, we have calculated the structural properties of the BaZrO{sub 3} (BZO) cubic structure with PBE-GGA, PBEsol-GGA, and LDA approximations. The equilibrium lattice constant within GGA-PBEsol (a = 4.1847 Å) is in very good agreement with the experimental data (Holland and Redfern, Miner. Mag. 61: 65, 1997). The calculations of elastic properties of pure and doped BaZrO{sub 3} are calculated with PBEsol-GGA; both BZO and BZM are compressible and show a brittle nature. According to calculated electronic and magnetic properties, it is found that Mn-doped BaZrO{sub 3} system is a half metallic and exhibits a ferromagnetic character. The total magnetic moment of the cell is equal to3.57 µ{sub B}; this value comes from manganese atom (Mn) with a value of 3.176 µ{sub B}. The magnetic moments of barium, oxygen, and zirconium atoms are approximately equal to zero.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Similar Exposure Group [Stick Welding without LEV - Manganese - RiskLevel 4]

This memorandum is presented to summarize quantitative worker exposure data collected while performing shielded metal arc welding (“SMAW” or “stick”) without local exhaust ventilation (LEV) and to validate if the appropriate risk level has been assigned to this task using Bayesian Decision Analysis (BDA). The purpose of this exposure assessment is to determine if it can be stated with at least 75% certainty that the true exposure profile (i.e., 95 th percentile) of the SEG is at or below the risk level currently assigned to this SEG.

61 RADIATION PROTECTION AND DOSIMETRY↗

Data Validation Package October 2015 Groundwater and Surface Water Sampling at the Monticello, Utah, Processing Site January 2016

Sampling Period: October 12–14, 2015. This semiannual event includes sampling groundwater and surface water at the Monticello Mill Tailings Site. Sampling and analyses were conducted as specified in the 2004 Monticello Mill Tailings Site Operable Unit III Post-Record of Decision Monitoring Plan, Draft Final and Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). Samples were collected from 52 of 61 planned locations (15 of 17 former mill site wells, 17 of 18 downgradient wells, 9 of 9 downgradient permeable reactive barrier wells, 2 of 7 seeps and wetlands, and 9 of 10 surface water locations). Locations MW00-07, Seep 1, Seep 2, Seep 3, Seep 5, Seep 6, SW00-01, T01-13, and T01-19 were not sampled because of insufficient water availability. All samples were filtered as specified in the monitoring plan. Duplicate samples were collected from surface water location W3-04 and from monitoring wells 82-08, 92-09, and 92-10. Water levels were measured at all but one sampled well and an additional set of wells. The contaminants of concern (COCs) for the Monticello Mill Tailings Site are arsenic, manganese, molybdenum, nitrate + nitrite as nitrogen (nitrate + nitrite as N), selenium, uranium, and vanadium. Time-concentration graphs of the COCs for all groundwater and surface water locations are included in this report. Locations with COCs that exceeded remediation goals are listed.

2015 Monticello↗

Final report for project "Effects of Low-Dose Irradiation on NFkB Signaling Networks and Mitochondria"

Low dose ionizing radiation effects are difficult to study in human population because of the numerous confounding factors such as genetic and lifestyle differences. Research in mammalian model systems and in vitro is generally used in order to overcome this difficulty. In this program project three projects have joined together to investigate effects of low doses of ionizing radiation. These are doses at and below 10 cGy of low linear energy transfer ionizing radiation such as X-ray and gamma rays. This project was focused on cellular signaling associated with nuclear factor kappa B (NFkB) and mitochondria - subcellular organelles critical for cell aging and aging-like changes induced by ionizing radiation. In addition to cells in culture this project utilized animal tissues accumulated in a radiation biology tissue archive housed at Northwestern University (http://janus.northwestern.edu/janus2/index.php). Major trust of Project 1 was to gather all of the DoE sponsored irradiated animal (mouse, rat and dog) data and tissues under one roof and investigate mitochondrial DNA changes and micro RNA changes in these samples. Through comparison of different samples we were trying to delineate mitochondrial DNA quantity alterations and micro RNA expression differences associated with different doses and dose rates of radiation. Historic animal irradiation experiments sponsored by DoE were done in several national laboratories and universities between 1950’s and 1990’s; while these experiments were closed data and tissues were released to Project 1. Project 2 used cells in culture to investigate effects that low doses or radiation have on NFκB and its target genes manganese superoxide dismutase (MnSOD) and genes involved in cell cycle: Cyclins (B1 and D1) and cyclin dependent kinases (CDKs). Project 3 used cells in culture such as “normal” human cells (breast epithelial cell line MCF10A cells and skin keratinocyte cells HK18) and mouse embryo fibroblast (mef) cells to focus on role of NFkB protein and several other proteins such as survivin (BIRC5) in radiation dependent regulation of tumor necrosis factor alpha (TNFα) and its downstream signaling.

59 BASIC BIOLOGICAL SCIENCES↗

Unusual magnetodielectric effects in La2CuMnO6 induced by a dynamic crossover in dielectric relaxation at TC

Highlights: • Ferromagnetic short-range correlations above T{sub C} = 72 K and a sign reversal of magnetoresistance around T{sub C}. • Dielectric relaxation in La{sub 2}CuMnO{sub 6}, with a dynamic (Arrhenius to Arrhenius) crossover at T{sub C}. • An unusual trend in the magnetodielectric coupling around T{sub C}. • A large magnetodielectric coupling of 55% at 68 K for 4 kHz and 61% at 105 K for 285.8 kHz under a magnetic field of 5 kOe. • Both the magnetic ordering and the external magnetic field control the electric dipole relaxation in the material. - Abstract: A series of fixed frequency dielectric measurements shows dielectric relaxation in La{sub 2}CuMnO{sub 6}, with a dynamic (Arrhenius to Arrhenius) crossover at T{sub C}. The external magnetic field alters the relaxation parameters in the vicinity of crossover and induces an unusual trend in the magnetodielectric coupling around T{sub C}. A large magnetodielectric coupling of 55% (at 68 K, 4 kHz) and 61% (at 105 K, 285.8 kHz) under a small magnetic field of 5 kOe is discovered. Presence of ferromagnetic short-range correlations above T{sub C} and a sign reversal of magnetoresistance around T{sub C} are observed. Specific heat analysis revealed the presence of ferromagnetic, variable range hopping active charge localized state. The presence of ferromagnetic short-range correlations and the influence of a core-grain dominated magnetoresistance on the Maxwell-Wagner interfacial polarization are responsible for the observed large magnetodielectric effect. Both the magnetic ordering and external magnetic field control the electric dipole relaxation in the material.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Intrinsic and extrinsic defects in a family of coal-derived graphene quantum dots

In this letter, we report on the high frequency (239.2 and 336 GHz) electron spin resonance (ESR) studies performed on graphene quantum dots (GQDs), prepared through a wet chemistry route from three types of coal: (a) bituminous, (b) anthracite, and (c) coke; and from non-coal derived GQDs. The microwave frequency-, power-, and temperature-dependent ESR spectra coupled with computer-aided simulations reveal four distinct magnetic defect centers. In bituminous- and anthracite-derived GQDs, we have identified two of them as intrinsic carbon-centered magnetic defect centers (a broad signal of peak to peak width = 697 (10{sup −4} T), g = 2.0023; and a narrow signal of peak to peak width = 60 (10{sup −4} T), g = 2.003). The third defect center is Mn{sup 2+} ({sup 6}S{sub 5/2}, 3d{sup 5}) (signal width = 61 (10{sup −4} T), g = 2.0023, A{sub iso} = 93(10{sup −4} T)), and the fourth defect is identified as Cu{sup 2+} ({sup 2}D{sub 5/2}, 3d{sup 9}) (g{sub ⊥} = 2.048 and g{sub ‖} = 2.279), previously undetected. Coke-derived and non-coal derived GQDs show Mn{sup 2+} and two-carbon related signals, and no Cu{sup 2+} signal. The extrinsic impurities most likely originate from the starting coal. Furthermore, Raman, photoluminescence, and ESR measurements detected no noticeable changes in the properties of the bituminous GQDs after one year. This study highlights the importance of employing high frequency ESR spectroscopy in identifying the (magnetic) defects, which are roadblocks for spin relaxation times of graphene-based materials. These defects would not have been possible to probe by other spin transport measurements.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

A data base of crop nutrient use, water use, and carbon dioxide exchange in a 2O square meter growth chamber: I. Wheat as a case study

A data set is given describing the daily nutrient uptake, gas exchange, environmental conditions, and carbon (C), and nutrient partitioning at harvest for the entire canopy and root system of a wheat crop (Triticum aestivum, cv. Yecora Rojo). The data were obtained from a 20 m2 stand of wheat plants grown from planting to maturity in a closed, controlled environment, and include daily nutrient uptake [macronutrients, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S); and micronutrients, iron (Fe), boron (B), manganese (Mn), zinc (Zn), copper (Cu), and molybdenum (Mo)], canopy carbon dioxide (CO2) exchange rates, and transpiration. Environmental factors such as relative humidity, air temperature, nutrient solution temperature, pH and electrical conductivity, and photoperiod were controlled in the chamber to specific set points. A detailed description of biomass yield for each of the 64 plant growth trays comprising the 20 m2 of growth area is also provided, and includes dry weights of grain, straw, chaff, and roots, along with the concentration of nutrients in different plant tissues and the percent carbohydrate, fat, and protein. To our knowledge, this information represents one of the most extensive data sets available for a canopy of wheat grown from seed to maturity under controlled environmental and nutritional conditions, and thus may provide useful information for model development and validation. A methods section is included to qualify any assumptions that might be required for the use of the data in plant growth models, along with a daily event calendar indicating when adjustments in set points and occasional equipment or sensor failures occurred.

NASA Discipline Number 61-20↗