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DOE OSTI2012

"DIAGNOSTIC" PULSE FOR SINGLE-PARTICLE-LIKE BEAM POSITION MEASUREMENTS DURING ACCUMULATION/PRODUCTION MODE IN THE LOS ALAMOS PROTON STORAGE RING

Beam position monitors (BPMs) are the primary diagnostic in the Los Alamos Proton Storage Ring (PSR). When injecting one turn, the transversemotion is approximated as a single particle with initial betatron position and angle {rvec x}{sub 0} and {rvec x}'{sub 0}. With single-turn injection, we fit the betatron tune, closed orbit (CO), and injection offset ({rvec x}{sub 0} and {rvec x}'{sub 0} at the injection point) to the turn-by-turn beam position. In production mode, we accumulate multiple turns, the transverse phase space fills after 5 injections (horizontal and vertical fractional betatron tunes {approx}0.2) resulting in no coherent betatron motion, and only the CO may be measured. The injection offset, which determines the accumulated beam size and is very sensitive to steering upstream of the ring, is not measurable in production mode. We describe our approach and ongoing efforts to measure the injection offset during production mode by injecting a 'diagnostic' pulse {approx}50 {micro}s after the accumulated beam is extracted. We also study the effects of increasing the linac RF gate length to accommodate the diagnostic pulse on the production beam position, transverse size, and loss.

43 PARTICLE ACCELERATORS↗

DOE OSTI2019

Superconducting Properties of LaSn{sub 3} Under Positive Hydrostatic Pressure

Superconducting properties of LaSn{sub 3} were calculated at ambient and applied positive hydrostatic pressure. The lattice structure of LaSn{sub 3} remained stable at ambient and all applied positive hydrostatic pressures due to the positive frequency of phonon dispersion plots for all modes of vibrations. The electron-phonon coupling constant (λ{sub ep}) and superconducting transition temperature (T{sub c}) show an almost linear decrease with positive hydrostatic pressure. The majority of electron‑electron interaction is mediated by acoustic modes of vibration in comparison to optical modes of vibrations.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2019

Effects of Nozzle Radial Position, Separation Angle, and Gas Flow Partitioning on the Mixing, Eye Area, and Wall Shear Stress in Ladles Fitted with Dual Plugs

Mixing time, slag eye area, and wall shear stress in a ladle fitted with dual plugs have been studied as a function of operating variables, namely, gas flow rate, radial nozzle position, separation angle between nozzles and flow rate partitioning. While the mixing time and slag eye area have been experimentally investigated in a scaled water model (with and without a top slag layer), the shear stress on the vessel wall has been studied computationally via a RANS-based turbulent, three-dimensional coupled Eulerian–Lagrangian (VOF-DPM), multiphase flow model. Experimental and computational results have indicated that the mixing, eye area, and wall shear stress depend on the gas flow rate, i.e., while mixing efficiency increases with the increasing gas flow rate, the slag eye area, and wall shear stress, in contrast, become more pronounced with the increasing gas flow, leading to an undesirable operating regime. The radial nozzle position, separation angle between the nozzles and flow rate partitioning at any given flow rate also influence the ladle process performance, influencing the mixing, eye area, and wall shear stress, albeit to a varied degree. Within the range of operating conditions studied, an expected inverse correspondence between mixing time and shear behavior was observed. Experimental and computational results in conjunction have indicated that the best arrangement of porous plugs or gas injection nozzles for superior ladle process performance is dependent on the gas flow rate and is specific to the desired objective (i.e., decreasing the mixing time, or slag eye area and wall shear stress). Hence, a unique gas injection practice cannot and should not be suggested as the optimum for ladle metallurgy in steelmaking. Nevertheless, if the mixing time is the parameter of primary interest, a nozzle configuration with equal flow partitioning (1:1) between the nozzles and identical nozzle radial positions (0.7R/0.7R, 45 deg) should suffice for both low and high gas flow rates. In contrast, a nonidentical nozzle radial position (0.7R/0.5R, 90 deg) and an unequal gas flow rate per nozzle (1:3) appear preferable if both ladle eye and shear stresses, rather than mixing, are the issues of concern.

36 MATERIALS SCIENCE↗

DOE OSTI2015

Entanglement and the process of measuring the position of a quantum particle

We explore the entanglement-related features exhibited by the dynamics of a composite quantum system consisting of a particle and an apparatus (here referred to as the “pointer”) that measures the position of the particle. We consider measurements of finite duration, and also the limit case of instantaneous measurements. We investigate the time evolution of the quantum entanglement between the particle and the pointer, with special emphasis on the final entanglement associated with the limit case of an impulsive interaction. We consider entanglement indicators based on the expectation values of an appropriate family of observables, and also an entanglement measure computed on particular exact analytical solutions of the particle–pointer Schrödinger equation. The general behavior exhibited by the entanglement indicators is consistent with that shown by the entanglement measure evaluated on particular analytical solutions of the Schrödinger equation. In the limit of instantaneous measurements the system’s entanglement dynamics corresponds to that of an ideal quantum measurement process. On the contrary, we show that the entanglement evolution corresponding to measurements of finite duration departs in important ways from the behavior associated with ideal measurements. In particular, highly localized initial states of the particle lead to highly entangled final states of the particle–pointer system. This indicates that the above mentioned initial states, in spite of having an arbitrarily small position uncertainty, are not left unchanged by a finite-duration position measurement process. - Highlights: • We explore entanglement features of a quantum position measurement. • We consider instantaneous and finite-duration measurements. • We evaluate the entanglement of exact time-dependent particle–pointer states.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2018

Maximally-localized position, Euclidean path-integral, and thermodynamics in GUP quantum mechanics

In dealing with quantum mechanics at very high energies, it is essential to adapt to a quasiposition representation using the maximally-localized states because of the generalized uncertainty principle. In this paper, we look at maximally-localized states as eigenstates of the operator ξ=X+iβP that we refer to as the maximally-localized position. We calculate the overlap between maximally-localized states and show that the identity operator can be expressed in terms of the maximally-localized states. Furthermore, we show that the maximally-localized position is diagonal in momentum-space and that the maximally-localized position and its adjoint satisfy commutation and anti-commutation relations reminiscent of the harmonic oscillator commutation and anti-commutation relations. As application, we use the maximally-localized position in developing the Euclidean path-integral and introduce the compact form of the propagator for maximal localization. The free particle momentum-space propagator and the propagator for maximal localization are analytically evaluated up to quadratic-order in β. Finally, we obtain a path-integral expression for the partition function of a thermodynamic system using the maximally-localized states. The partition function of a gas of noninteracting particles is evaluated. At temperatures exceeding the Planck energy, we obtain the gas’ maximum internal energy N∕2β and recover the zero heat capacity of an ideal gas.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2013

Dissect Kif5b in nuclear positioning during myogenesis: The light chain binding domain and the autoinhibitory peptide are both indispensable

Highlights: ► Kif5b localizes at myonuclear membrane and is responsible for nuclear dispersion. ► Kif5b stalk/tail domain contains signal for nuclear membrane targeting. ► Kif5b stalk/tail domain directly binds to a nesprin 4 in vitro. ► KLC binding domain and autoinhibitory peptide are both functionally indispensable. -- Abstract: The microtubule motor kinesin-1 is responsible for the nuclear positioning during myogenesis. Here we show that the coiled-coil stalk/tail domain containing the kinesin light chain (KLC) binding sites targets to the perinuclear region like endogenous Kif5b, while the globular tail domain cannot. To investigate which fragments of kinesin heavy chain (Kif5b) is responsible for the myonuclear positioning, we transfect Kif5b expression constructs into Kif5b deficient myoblasts and test their ability to rescue the myonuclear phenotype. We find that the KLC binding domain and the autoinhibitory peptide in the globular tail region are both indispensable for the nuclear membrane localization of Kif5b and the kinesin-1-mediated myonuclear positioning. These results suggest that while the KLC binding domain may directly targets Kif5b to the myonuclear membrane, the autoinhibitory peptide may play an indirect role in regulating the kinesin-1-mediated myonuclear positioning.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2021

Position-specific isotope effects during alkaline hydrolysis of 2,4-dinitroanisole resolved by compound-specific isotope analysis, 13 C NMR, and density-functional theory

Compound-specific isotope analysis (CSIA), position-specific isotope analysis (PSIA), and computational modeling (e.g., quantum mechanical models; reactive-transport models) are increasingly being used to monitor and predict biotic and abiotic transformations of organic contaminants in the field. However, identifying the isotope effect(s) associated with a specific transformation remains challenging in many cases. We describe and interpret the position-specific isotope effects of C and N associated with a SN 2 Ar reaction mechanism by a combination of CSIA and PSIA using quantitative 13 C nuclear magnetic resonance spectrometry, and density-functional theory, using 2,4-dinitroanisole (DNAN) as a model compound. The position-specific 13 C enrichment factor of O–C 1 bond at the methoxy group attachment site (ε C1 ) was found to be approximately -41‰, a diagnostic value for transformation of DNAN to its reaction products 2,4-dinitrophenol and methanol. Theoretical kinetic isotope effects calculated for DNAN isotopologues agreed well with the position-specific isotope effects measured by CSIA and PSIA. This combination of measurements and theoretical predictions demonstrates a useful tool for evaluating degradation efficiencies and/or mechanisms of organic contaminants and may promote new and improved applications of isotope analysis in laboratory and field investigations.

13C NMR↗

DOE OSTI2022

Parameterization of generic positive sequence models to represent behavior of inverter based resources in low short circuit scenarios

The connection of large inverter based resources (IBR) in transmission systems is often located geographically and electrically far away from load centers. This, coupled with the displacement of synchronous machine plants, results in a reduction of the network short circuit strength at the point of connection. Under these conditions, state-of-the-art positive sequence simulation platforms and models can have difficulties maintaining numerical stability and/or providing an accurate representation of IBR plant dynamic behavior. As a result, computationally heavy time domain electromagnetic transient (EMT) simulations may be required to evaluate these systems. In this paper, a recently developed improved generic positive sequence model is parameterized to provide a representation of IBR behavior in low short circuit networks. Further, comparisons against generic and detailed EMT models demonstrate the suitability of the improved positive sequence model to study practical stability issues experienced with presently in-service plants. Such a model can provide some of the accuracy of an EMT representation with a much lower computational burden. The performance of the positive sequence model is validated against the behavior shown by both open white box and closed black box EMT domain models from around the world.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2018

Improved sensing of vertical velocity for vertical position control using loop voltage signals on EAST

Vertical position control of shaped plasma is critical for all elongated tokamaks to achieve safe and stable plasma discharge. In EAST, the in-vessel coil (IC) is employed for fast control of plasma vertical motion which power supply capabilities limits the controllability of vertical instability. Moreover, adequate signal-to-noise ratio of vertical position measurement can also realize an improvement in vertical control. In EAST, plasma vertical position Z p is produced nearly by all integrated magnetics, fast Z error signal is obtained by filtering from Zp. Then this fast Z error and its derivative term (dz/dt) are controlled by IC with a separate PD controller. Yet, it has a low signal-to-noise ratio which limits the gains that can be used successfully in the PD control loops. To provide less noisy dz/dt signal, the successful use of multiple up/down loop voltage pairs instead of derivative of z derived from magnetic probe signals will be discussed. Experiment show that even a single pair of loop voltage signal has better signal-to-noise ratio than differentiation of Z p . In addition, flux loop pickup signals from the IC current are also measured with series of positive and negative IC current pulses.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

DOE OSTI2012

Matched Cohort Analysis of Outcomes of Definitive Radiotherapy for Prostate Cancer in Human Immunodeficiency Virus-Positive Patients

Purpose: To compare the biochemical outcome and toxicity scores of men with human immunodeficiency virus (HIV) and prostate cancer with a matched control population with negative or unknown HIV status when treated with external-beam radiotherapy (EBRT). Methods and Materials: A single-institution database of men with prostate cancer treated with EBRT from 1999 to 2009 was reviewed. Thirteen men with HIV were identified and matched to 2 control patients according to age, race, T stage, prostate-specific antigen level, Gleason score, RT dose, intensity-modulated RT vs. three-dimensional conformal RT, and whole-pelvis vs. prostate-only RT, for a total of 39 cases. The median follow-up time was 39 months (range, 3-110 months). Results: The 4-year biochemical failure (BF)-free survival rate was 87% in the HIV-positive group vs. 89% in the controls (p = 0.94). Pre- and post-RT viral loads were found to be predictive of BF (p = 0.04 and p = 0.04, respectively). No men with HIV died, whereas 2 in the control group died of causes unrelated to prostate cancer. Acute and chronic genitourinary and gastrointestinal toxicity were less in the HIV-positive patients than in controls (p < 0.001, p < 0.001, p = 0.003, and p < 0.001, respectively). The HIV-positive men experienced an average decline in CD4 count of 193 cells/mm{sup 3}. Conclusions: Our findings suggest that men with HIV treated with EBRT have a similar risk of BF; however, high viral loads may contribute to an increased risk. This analysis supports that HIV-positive men with prostate cancer can be treated with definitive EBRT with similar disease control and toxicity outcomes as in the general population.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2014

The Impact of Definitive Local Therapy for Lymph Node-Positive Prostate Cancer: A Population-Based Study

Purpose: To evaluate the survival outcomes for patients with lymph node-positive, nonmetastatic prostate cancer undergoing definitive local therapy (radical prostatectomy [RP], external beam radiation therapy [EBRT], or both) versus no local therapy (NLT) in the US population in the modern prostate specific antigen (PSA) era. Methods and Materials: The Surveillance, Epidemiology, and End Results database was queried for patients with T1-4N1M0 prostate cancer diagnosed from 1995 through 2005. To allow comparisons of equivalent datasets, patients were analyzed in separate clinical (cN+) and pathologically confirmed (pN+) lymph node-positive cohorts. Kaplan-Meier overall survival (OS) and prostate cancer-specific survival (PCSS) estimates were generated, with accompanying univariate log-rank and multivariate Cox proportional hazards comparisons. Results: A total of 796 cN+ and 2991 pN+ patients were evaluable. Among cN+ patients, 43% underwent EBRT and 57% had NLT. Outcomes for cN+ patients favored EBRT, with 10-year OS rates of 45% versus 29% (P<.001) and PCSS rates of 67% versus 53% (P<.001). Among pN+ patients, 78% underwent local therapy (RP 57%, EBRT 10%, or both 11%) and 22% had NLT. Outcomes for pN+ also favored local therapy, with 10-year OS rates of 65% versus 42% (P<.001) and PCSS rates of 78% versus 56% (P<.001). On multivariate analysis, local therapy in both the cN+ and pN+ cohorts remained independently associated with improved OS and PCSS (all P<.001). Local therapy was associated with favorable hazard ratios across subgroups, including patients aged ≥70 years and those with multiple positive lymph nodes. Among pN+ patients, no significant differences in survival were observed between RP versus EBRT and RP with or without adjuvant EBRT. Conclusions: In this large, population-based cohort, definitive local therapy was associated with significantly improved survival in patients with lymph node-positive prostate cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2014

Extended Field Intensity Modulated Radiation Therapy With Concomitant Boost for Lymph Node–Positive Cervical Cancer: Analysis of Regional Control and Recurrence Patterns in the Positron Emission Tomography/Computed Tomography Era

Purpose: Positron emission tomography/computed tomography (PET/CT) is commonly used for nodal staging in locally advanced cervical cancer; however the false negative rate for para-aortic disease are 20% to 25% in PET-positive pelvic nodal disease. Unless surgically staged, pelvis-only treatment may undertreat para-aortic disease. We have treated patients with PET-positive nodes with extended field intensity modulated radiation therapy (IMRT) to address the para-aortic region prophylactically with concomitant boost to involved nodes. The purpose of this study was to assess regional control rates and recurrence patterns. Methods and Materials: Sixty-one patients with cervical cancer (stage IBI-IVA) diagnosed from 2003 to 2012 with PET-avid pelvic nodes treated with extended field IMRT (45 Gy in 25 fractions with concomitant boost to involved nodes to a median of 55 Gy in 25 fractions) with concurrent cisplatin and brachytherapy were retrospectively analyzed. The nodal location was pelvis-only in 41 patients (67%) and pelvis + para-aortic in 20 patients (33%). There were a total of 179 nodes, with a median number of positive nodes of 2 (range, 1-16 nodes) per patient and a median nodal size of 1.8 cm (range, 0.7-4.5 cm). Response was assessed by PET/CT at 12 to 16 weeks. Results: Complete clinical and imaging response at the first follow-up visit was seen in 77% of patients. At a mean follow-up time of 29 months (range, 3-116 months), 8 patients experienced recurrence. The sites of persistent/recurrent disease were as follows: cervix 10 (16.3%), regional nodes 3 (4.9%), and distant 14 (23%). The rate of para-aortic failure in patients with pelvic-only nodes was 2.5%. There were no significant differences in recurrence patterns by the number/location of nodes, largest node size, or maximum node standardized uptake value. The rate of late grade 3+ adverse events was 4%. Conclusions: Extended field IMRT was well tolerated and resulted in low regional recurrence in node-positive cervical cancer. The dose of 55 Gy in 25 fractions was effective in eradicating disease in involved nodes, with acceptable late adverse events. Distant metastasis is the predominant mode of failure, and the OUTBACK trial may challenge the presented paradigms.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2016

The Outcome for Patients With Pathologic Node-Positive Prostate Cancer Treated With Intensity Modulated Radiation Therapy and Androgen Deprivation Therapy: A Case-Matched Analysis of pN1 and pN0 Patients

Purpose: Improved outcome is reported after surgery or external beam radiation therapy (EBRT) plus androgen deprivation therapy (ADT) for patients with lymph node (LN) positive (N1) prostate cancer (PC). Surgical series have shown that pathologic (p)N1 PC does not behave the same in all patients. The aim of this study was to perform a matched-case analysis to compare the outcome of pN1 and pN0 PC after high-dose EBRT plus ADT. Methods and Materials: Radiation therapy up to 80 Gy was delivered to the prostate with a minimal dose of 45 Gy to the pelvis for pN1 patients. After matching, Kaplan-Meier statistics were used to compare the 5-year biochemical and clinical relapse-free survival (bRFS and cRFS), prostate cancer–specific survival (PCSS), and overall survival (OS). Acute and late rectal and urinary toxicity was evaluated. Results: Sixty-nine pN1 PC patients were matched 1:1 with pN0 PC patients. The median follow-up time was 60 months. The 5-year bRFS and cRFS for pN1 versus pN0 PC patients were 65% ± 7% versus 79% ± 5% (P=.08) and 70% ± 6% versus 83% ± 5% (P=.04) respectively. No significant difference was found in bRFS or cRFS rates between low volume pN1 (≤2 positive LNs) and pN0 patients. The 5-year PCSS and OS were comparable between pN1 and pN0 PC patients: PCSS: 92% ± 4% versus 93% ± 3% (P=.66); OS: 82% ± 5% versus 80% ± 5% (P=.58). Severe toxicity was rare for both groups, although pN1 patients experienced significantly more acute grade 2 rectal toxicity. Conclusion: Primary EBRT plus 2 to 3 years of ADT is a legitimate treatment option for pN1 PC patients, especially those with ≤2 positive LNs, and this with bRFS and cRFS rates comparable to those in pN0 PC patients. For pN1 PC patients with >2 positive LNs, bRFS and cRFS are worse than in pN0 patients, but even in this subgroup, long-term disease control is obtained.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2017

Favorable Local Control From Consolidative Radiation Therapy in High-Risk Neuroblastoma Despite Gross Residual Disease, Positive Margins, or Nodal Involvement

Purpose: To report the influence of radiation therapy (RT) dose and surgical pathology variables on disease control and overall survival (OS) in patients treated for high-risk neuroblastoma at a single institution. Methods and Materials: We conducted a retrospective study of 67 high-risk neuroblastoma patients who received RT as part of definitive management from January 2003 until May 2014. Results: At a median follow-up of 4.5 years, 26 patients (38.8%) failed distantly; 4 of these patients also failed locally. One patient progressed locally without distant failure. Local control was 92.5%, and total disease control was 59.5%. No benefit was demonstrated for RT doses over 21.6 Gy with respect to local relapse–free survival (P=.55), disease-free survival (P=.22), or OS (P=.72). With respect to local relapse–free survival, disease-free survival, and OS, no disadvantage was seen for positive lymph nodes on surgical pathology, positive surgical margins, or gross residual disease. Of the patients with gross residual disease, 75% (6 of 8) went on to have no evidence of disease at time of last follow-up, and the 2 patients who failed did so distantly. Conclusions: Patients with high-risk neuroblastoma in this series maintained excellent local control, with no benefit demonstrated for radiation doses over 21.6 Gy, and no disadvantage demonstrated for gross residual disease after surgery, positive surgical margins, or pathologic lymph node positivity. Though the limitations of a retrospective review for an uncommon disease must be kept in mind, with small numbers in some of the subgroups, it seems that dose escalation should be considered only in exceptional circumstances.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2017

Postmastectomy Radiation Therapy Is Associated With Improved Survival in Node-Positive Male Breast Cancer: A Population Analysis

Purpose: Because of its rarity, there are no randomized trials investigating postmastectomy radiation therapy (PMRT) in male breast cancer. This study retrospectively examines the impact of PMRT in male breast cancer patients in the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. Methods and Materials: The SEER database 8.3.2 was queried for men ages 20+ with a diagnosis of localized or regional nonmetastatic invasive ductal/lobular carcinoma from 1998 to 2013. Included patients were treated by modified radical mastectomy (MRM), with or without adjuvant external beam radiation. Univariate and multivariate analyses evaluated predictors for PMRT use after MRM. Kaplan-Meier overall survival (OS) curves of the entire cohort and a case-matched cohort were calculated and compared by the log-rank test. Cox regression was used for multivariate survival analyses. Results: A total of 1933 patients were included in the unmatched cohort. There was no difference in 5-year OS between those who received PMRT and those who did not (78% vs 77%, respectively, P=.371); however, in the case-matched analysis, PMRT was associated with improved OS at 5 years (83% vs 54%, P<.001). On subset analysis of the unmatched cohort, PMRT was associated with improved OS in men with 1 to 3 positive nodes (5-year OS 79% vs 72% P=.05) and those with 4+ positive nodes (5-year OS 73% vs 53% P<.001). On multivariate analysis of the unmatched cohort, independent predictors for improved OS were use of PMRT: HR=0.551 (0.412-0.737) and estrogen receptor–positive disease: HR=0.577 (0.339-0.983). Predictors for a survival detriment were higher grade 3/4: HR=1.825 (1.105-3.015), larger tumor T2: HR=1.783 (1.357-2.342), T3/T4: HR=2.683 (1.809-3.978), higher N-stage: N1 HR=1.574 (1.184-2.091), N2/N3: HR=2.328 (1.684-3.218), black race: HR=1.689 (1.222-2.336), and older age 81+: HR=4.164 (1.497-11.582). Conclusions: There may be a survival benefit with the addition of PMRT for male breast cancer with node-positive disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2018

A composite position independent monitor of reactor fuel irradiation using Pu, Cs, and Ba isotope ratios

When post-irradiation materials from the nuclear fuel cycle are released to the environment, certain isotopes of actinides and fission products carry signatures of irradiation history that can potentially aid a nuclear forensic investigation into the material's provenance. In this study, combinations of Pu, Cs, and Ba isotope ratios that produce position (in the reactor core) independent monitors of irradiation history in spent light water reactor fuel are identified and explored. These position independent monitors (PIMs) are modeled for various irradiation scenarios using automated depletion codes as well as ordinary differential equation solutions to approximate nuclear physics models. Experimental validation was performed using irradiated low enriched uranium oxide fuel from a light water reactor, which was sampled at 8 axial positions from a single rod. Plutonium, barium and cesium were chemically separated and isotope ratio measurements of the separated solutions were made by quadrupole and multi-collector inductively coupled mass spectrometry (Cs and Pu, respectively) and thermal ionization mass spectrometry (Ba). The effect of axial variations in neutron fluence and energy spectrum are evident in the measured isotope ratios. Furthermore, two versions of a combined Pu and Cs based PIM are developed. A linear PIM model, which can be used to solve for irradiation time is found to work well for natural U fuel with <10% 240 Pu and known or short cooling times. A non-linear PIM model, which cannot be solved explicitly for irradiation time without additional information, can nonetheless still group samples by irradiation history, including high burnup LEU fuel with unknown cooling time. 137 Ba/ 138 Ba is also observed to act as a position independent monitor; it is nearly single valued across the sampled fuel rod, indicating that samples sharing an irradiation history (same irradiation time and cooling time) in a reactor despite experiencing different neutron fluxes will have a common 137 Ba/ 138 Ba ratio. Modeling of this Ba PIM shows it increases monotonically with irradiation and cooling time, and a confirmatory first order analytical solution is also presented.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2014

Line positions and intensities of the phosphine (PH 3 ) Pentad near 4.5μm

In order to improve the spectroscopic database for remote sensing of the giant planets, line positions and intensities are determined for the five bands (2ν 2 , ν 2 + ν 4 , 2ν 4 , ν 1 and ν 3 ) that comprise the Pentad of PH 3 between 1950 and 2450 cm -1 . Knowledge of PH 3 spectral line parameters in this region is important for the exploration of dynamics and chemistry on Saturn, (using existing Cassini/VIMS observations) and future near-IR data of Jupiter from Juno and ESA’s Jupiter Icy Moons Explorer (JUICE). For this study, spectra of pure PH 3 from two Fourier transform spectrometers were obtained: (a) five high-resolution (0.00223 cm -1 ), high signal-to-noise (~1800) spectra recorded at room temperature (298.2 K) with the Bruker IFS 125HR Fourier transform spectrometer (FTS) at the Pacific Northwest National Laboratory (PNNL), Richland, Washington and (b) four high-resolution (at 0.0115 cm -1 resolution), high signal-to-noise (~700) spectra recorded at room temperature in the region 1800–5200 cm -1 using the McMath-Pierce Fourier transform spectrometer located at the National Solar Observatory (NSO) on Kitt Peak. Individual line parameters above 2150 cm -1 were retrieved by simultaneous multispectrum fittings of all five Bruker spectra, while retrievals with the four Kitt Peak spectra were done in the 1938–2168 cm -1 range spectrum by spectrum and averaged. In all, positions and intensities were obtained for more than 4400 lines. These included 53 A+A- split pairs of transitions (arising due to vibration–rotation interactions (Coriolis-type interaction) between the ν 3 and ν 1 fundamental bands) for K" = 3, 6, and 9. Over 3400 positions and 1750 intensities of these lines were ultimately identified as relatively unblended and modeled up to J = 14 and K = 12 with rms values of 0.00133 cm -1 and 7.7%, respectively. The PH 3 line parameters (observed positions and measured intensities with known quantum assignments) and Hamiltonian constants are reported. Finally, comparisons with other recent studies are discussed.

Environmental Molecular Sciences Laboratory↗

DOE OSTI2015

Effect of intrafractional prostate motion on simultaneous boost intensity-modulated radiotherapy to the prostate: A simulation study based on intrafractional motion in the prone position

Although the prostate displacement of patients in the prone position is affected by respiration-induced motion, the effect of intrafractional prostate motion in the prone position during “simultaneous integrated boost intensity-modulated radiotherapy” (SIB-IMRT) is unclear. The purpose of this study was to evaluate the dosimetric effects of intrafractional motion on SIB-IMRT to a dominant intraprostatic lesion (IPL) using measured motion data of patients in a prone position, fixed with a thermoplastic shell. We obtained 2 orthogonal x-ray fluoroscopic images at the same moment every 0.2 seconds for 30 seconds before and after treatment, once weekly, from 7 patients with localized prostate cancer with detectable prostatic calcification. Prostate displacements in the left-right (LR), anteroposterior (AP), and superoinferior (SI) directions were calculated using the prostatic calcification as a fiducial marker. We defined the displacement between pretreatment and posttreatment as baseline drift (BD). An SIB-IMRT plan was generated in which each IPL + 3 mm received a dose of 94.5 Gy, whereas the remainder of the prostate + 7 mm received a dose of 75.6 Gy in 9 fields. A simulated plan of dose blurring was generated by the convolution of isocenter-shifted plans using measured motion data in 30 seconds and motion in 30 seconds + distance between pretreatment and posttreatment position (BD) for each of the 7 patients. The motion in 30 seconds mainly reflected respiration-induced motion. The mean displacements of BD were 1.4 mm (− 3.1 to 8.2 mm), − 2.2 mm (− 9.1 to 1.5 mm), and − 0.3 mm (− 5.0 to 1.8 mm) in the AP, SI, and LR directions, respectively. The differences in the target coverage with V{sub 90%} of the IPL and V{sub 100%} of the prostate between the simulated plan and original plan were − 3.9% to − 0.3% and − 0.6% to 1.1% for respiration-induced motion and 3.1% to − 67.8% and 3.6% to − 13.3% for BD with respiration-induced motion, respectively. The large motion of BD resulted in an inadequate coverage by the prescribed dose of the SIB-IMRT to the IPL. A 7-mm margin is recommended when real-time tracking techniques are not applied. The effect of respiration-induced motion was small, so long as a 3-mm margin was added.

61 RADIATION PROTECTION AND DOSIMETRY↗