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All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Technical Solutions to Ensure Safe Yttrium-90 Radioembolization in Patients With Initial Extrahepatic Deposition of {sup 99m}Technetium-Albumin Macroaggregates

Purpose: To evaluate the incidence of extrahepatic deposition of technetium-99m-labeled albumin macroaggregates ({sup 99m}Tc-MAA) after pretreatment angiography, before yttrium-90 radioembolizaton ({sup 90}Y-RE), and to report on technical solutions that can be used to ensure safe delivery of {sup 90}Y-microspheres in patients with initial extrahepatic deposition. Materials and Methods: A retrospective analysis of 26 patients with primary and secondary liver malignancies, who were scheduled for treatment with {sup 90}Y-RE in our institution in 2009, was performed. The angiograms and single-photon emission computed tomography images of all patients were reviewed by an interventional radiologist and a nuclear medicine physician, respectively, to identify and localize extrahepatic deposition of {sup 99m}Tc-MAA when present. Subsequently, the technical solutions were used to successfully perform {sup 90}Y-RE in these patients were evaluated and described. Results: Extrahepatic deposition of {sup 99m}Tc-MAA was observed in 8 of 26 patients (31%). In 7 of 8 patients, a second pretreatment angiography was performed to detect the cause of extrahepatic deposition. The technical solutions to enable safe {sup 90}Y microspheres delivery included more distal placement of the microcatheter in the proper/right hepatic artery in 4 of 7 (57%) patients; (super)selective catheterization of multiple segmental branches in 2 of 7 (29%); and additional coiling of a newly detected branch in the remaining patient (14%). This was confirmed by a second MAA procedure. {sup 90}Y-RE was eventually performed in 25 of 26 (96%) patients. No procedure-related complications (<30 days) were observed. Conclusion: Extrahepatic deposition of {sup 99m}Tc-MAA after pretreatment angiography did occur in 8 of 26 (31%) patients. The technical solutions as presented allowed safe {sup 90}Y-RE delivery in 25 of 26 (96%) patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Transarterial Hepatic Yttrium-90 Radioembolization in Patients with Unresectable Intrahepatic Cholangiocarcinoma: Factors Associated with Prolonged Survival

Introduction: In unresectable intrahepatic cholangiocarcinoma (ICC), systemic chemotherapy often is viewed as the only option, although efficacy is limited. Radioembolization (RE) using yttrium-90 ({sup 90}Y) microspheres is an accepted therapy for patients with hepatocellular-carcinoma or metastatic liver tumors. However, there are limited data on the value of RE in patients with ICC and few data on factors influencing prognosis. The purpose of our retrospective analysis was to establish which factors influenced time-to-progression (TTP) and overall survival (OS). Methods: Patients with unresectable ICC were treated with {sup 90}Y resin-microspheres and assessed at 3-monthly intervals. Radiologic response was evaluated by using Response Criteria in Solid Tumors (RECIST). Baseline characteristics, biochemical/clinical toxicities, and response were examined for impact on TTP and OS. Results: Thirty-four treatments were administered to 33 patients without major complications. By RECIST, 12 patients had a partial response, 17 had stable disease, and 5 had progressive disease after 3 months. The median OS was 22 months posttreatment and 43.7 months postdiagnosis. Median TTP was 9.8 months. Survival and TTP were significantly prolonged in patients with ECOG 0 (vs. ECOG 1 or 2; median OS: 29.4, 10, and 5.1 months; TTP: 17.5, 6.9, and 2.4 months), tumor burden {<=}25% (OS: 26.7 vs. 6 months; TTP: 17.5 vs. 2.3 months), or tumor response (PR or SD vs. PD; OS: 35.5, 17.7 vs. 5.7 months; TTP: 31.9, 9.8 vs. 2.5 months), respectively (P < 0.001). Conclusions: Radioembolization is an effective and safe option for patients with unresectable ICC. Predictors for prolonged survival are performance status, tumor burden, and RECIST response.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Practical Vascular Anatomy in the Preparation of Radioembolization

As the incidence of primary and metastatic liver cancer continues to increase, the use of minimally invasive techniques as a treatment option is becoming more common. Radioembolization, a form of intra-arterial brachytherapy, is a technique where particles of glass or resin, impregnated with the isotope {sup 90}yttrium ({sup 90}Y), are infused through a catheter directly into the hepatic arteries. This modality is based on the fact that hepatic malignancies receive their blood supply from the hepatic artery, whereas normal hepatocytes are perfused mostly from the portal circulation, which allows delivery of high doses to the tumor vasculature with relative sparing of normal liver tissue. This has been shown to be effective for both primary and metastatic tumors. A variety of complications may be related to hepatic intra-arterial treatments, especially to the gastroduodenal region. These complications are known to come from inadvertent extrahepatic infusion of {sup 90}Y particles, through arteries originating from the hepatic arterial branches such as the falciform artery, cystic artery, arteries from the pancreaticoduodenal arcade, gastroduodenal artery, or right gastric artery. Surgeons and interventional radiologists rely on accurate imaging and assessment of the hepatic arterial supply. It is important to know the common anatomic variations and technical considerations before radioembolization. We recommend an aggressive occlusion of all the above-mentioned arteries; further, clinicians should watch out for any other aberrant branches, and if in doubt, they ought to be coiled.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Changes in Normal Liver and Spleen Volume after Radioembolization with {sup 90}Y-Resin Microspheres in Metastatic Breast Cancer Patients: Findings and Clinical Significance

Purpose: In clinical trials with yttrium-90-resin-microspheres for the management of colorectal cancer liver metastases, it was observed that radioembolization might result in splenomegaly and an increase in portal vein size. Subclinical hepatitis in normal liver tissue as well as the effects of radioembolization and prior chemotherapy are suspected to be responsible for this phenomenon. The purpose of this study was to quantify the changes in liver and spleen volume and portal vein diameter after radioembolization. Methods: Twenty-seven patients with liver-dominant metastatic disease from breast cancer who had not responded to chemotherapy or had to abandon chemotherapy because of its toxic effects were evaluated. Changes in liver and spleen volume and portal vein diameter as well as liver tumor volume and diameter were quantified using computed tomography scans. Results: Radioembolization was associated with a significant mean decrease in the whole liver volume of 10.2% (median 16.7%; P = 0.0024), mainly caused by a reduction in the right lobe volume (mean 16.0%; P < 0.0001). These changes were accompanied by a significant increase in the diameter of the main portal vein (mean 6.8%; P < 0.0001) as well as splenic volume (mean 50.4%; P < 0.0001). Liver-tumor volume and diameter decreased by a median of 24 and 39.7%. Conclusions: Radioembolization is an effective treatment for tumor size reduction in patients with breast cancer liver metastases. Treatment is associated with changes of hepatic parenchymal volume, splenic volume, and portal vein size that appear not to represent clinically important sequelae in this patient cohort.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Superselective Internal Radiation With Yttrium-90 Microspheres in the Management of a Chemorefractory Testicular Liver Metastasis

We treated a patient with biopsy-proven, chemotherapy-resistant testicular cancer liver metastasis using Y-90 selective internal radiation treatment. We chose yttrium-90 rather than surgery and ablation due to tumor location and size as well as the patient's clinical history. The result was marked tumor response by positron emission tomography and computed tomography as well as significant improvement of the patient's quality of life accompanied by a substantial decrease of his tumor markers.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Radioembolization of Symptomatic, Unresectable Neuroendocrine Hepatic Metastases Using Yttrium-90 Microspheres

Purpose: To evaluate safety, efficacy, and symptom-control of radioembolization in patients with unresectable liver metastases from neuroendocrine tumors (NETLMs). Materials and Methods: Forty-two patients (mean age of 62 years) with treatment-refractory NETLMs underwent radioembolization using yttrium-90 ({sup 90}Y) resin microspheres. Posttreatment tumor response was assessed by cross-sectional imaging using the Response Evaluation Criteria in Solid Tumors (RECIST) and tumor-marker levels. Laboratory and clinical toxicities and clinical symptoms were monitored. Results: The median activity delivered was 1.63 GBq (range 0.63-2.36). Imaging follow-up using RECIST at 3-month follow-up demonstrated partial response, stable disease, and progressive disease in 22.5, 75.0, and 2.5% of patients, respectively. In 97.5% of patients, the liver lesions appeared hypovascular or partially necrotic. The mean follow-up was 16.2 months with 40 patients (95.2%) remaining alive. The median decrease in tumor-marker levels at 3 months was 54.8% (chromogranin A) and 37.3% (serotonin), respectively. There were no acute or delayed toxicities greater than grade 2 according to Common Terminology Criteria for Adverse Events [CTCAE (v3.0)]. No radiation-induced liver disease was noted. Improvement of clinical symptoms 3 months after treatment was observed in 36 of 38 symptomatic patients. Conclusion: Radioembolization with {sup 90}Y-microspheres is a safe and effective treatment option in patients with otherwise treatment-refractory NETLMs. Antitumoral effect is supported by good local tumor control, decreased tumor-marker levels, and improved clinical symptoms. Further investigation is warranted to define the role of radioembolization in the treatment paradigm for NETLMs.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Computed Tomography-Guided Interstitial HDR Brachytherapy (CT-HDRBT) of the Liver in Patients with Irresectable Intrahepatic Cholangiocarcinoma

Purpose: This study was designed to investigate the clinical outcome of patients with irresectable, intrahepatic cholangiocarcinoma (IHC) treated with computed tomography (CT)-guided HDR-brachytherapy (CT-HDRBT) for local tumor ablation.MethodFifteen consecutive patients with histologically proven cholangiocarcinoma were selected for this retrospective study. Patients were treated by high-dose-rate internal brachytherapy (HDRBT) using an Iridium-192 source in afterloading technique through CT-guided percutaneous placed catheters. A total of 27 brachytherapy treatments were performed in these patients between 2006 and 2009. Median tumor enclosing target dose was 20 Gy, and mean target volume of the radiated tumors was 131 ({+-} 90) ml (range, 10-257 ml). Follow-up consisted of clinical visits and magnetic resonance imaging of the liver every third month. Statistical evaluation included survival analysis using the Kaplan-Meier method. Results: After a median follow-up of 18 (range, 1-27) months after local ablation, 6 of the 15 patients are still alive; 4 of them did not get further chemotherapy and are regarded as disease-free. The reached median local tumor control was 10 months; median local tumor control, including repetitive local ablation, was 11 months. Median survival after local ablation was 14 months and after primary diagnosis 21 months. Conclusion: In view of current clinical data on the clinical outcome of cholangiocarcinoma, locally ablative treatment with CT-HDRBT represents a promising and safe technique for patients who are not eligible for tumor resection.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Uptake of chloride and carbonate ions by calcium monosulfoaluminate hydrate

Decommissioning of old nuclear reactors may produce waste streams containing chlorides and carbonates, including radioactive {sup 36}Cl{sup -} and {sup 14}CO{sub 3}{sup 2-}. Their insolubilization by calcium monosulfoaluminate hydrate was investigated. Carbonates were readily depleted from the solution, giving at thermodynamic equilibrium monocarboaluminate, monocarboaluminate + calcite, or calcite only, depending on the initial ratio between the anion and calcium monosulfoaluminate hydrate. Chloride ions reacted more slowly and were precipitated as Kuzel's salt, Kuzel's and Friedel's salts, or Friedel's salt only. Rietveld refinement of X-Ray powder diffraction patterns was successfully used to quantify the phase distributions, which were compared to thermodynamic calculations. Moreover, analysing the lattice parameters of Kuzel's salt as a function of its chloride content showed the occurrence of a restricted solid solution towards the sulfate side with general formula 3CaO{center_dot}Al{sub 2}O{sub 3}{center_dot}xCaCl{sub 2}{center_dot}(1 - x)CaSO{sub 4}{center_dot}(12 - 2x){center_dot}H{sub 2}O (0.36 {<=} x {<=} 0.50).

36 MATERIALS SCIENCE↗
DOE OSTI2011

Retrospective Analysis of Local Control and Cosmetic Outcome of 147 Periorificial Carcinomas of the Face Treated With Low-Dose Rate Interstitial Brachytherapy

Purpose: Skin cancer is the most common malignancy in white populations. We evaluated the local cure rate and cosmetic outcome of patients with basal cell carcinoma (BCC) or squamous cell carcinoma (SCC) of the face treated with low-dose rate brachytherapy. Methods and Materials: Between February 1990 and May 2000, 147 facial carcinomas in 132 patients were treated by {sup 192}Ir wire implantation. Side effects of brachytherapy were noted. Follow-up was 2 years or more. Locoregional recurrence-free survival (LRFS) and overall survival were recorded. Group A included patients treated by primary brachytherapy, and Group B included those treated after recurrence. Results: A total of 121 carcinomas were BCCs (82.3%) and 26 were SCCs (17.7%); the median tumor size was 10 mm. Of the tumors, 86 (58.5%) were in men and 61 (41.5%) were in women; the median age was 71 years. Group A comprised 116 lesions (78.9%), and Group B, 31 (21.1%). There were 17 relapses (11.6%) after a median follow-up of 72 months: 12 local, 4 nodal, and 1 local and nodal. Locoregional-free survival was 96.6% at 2 years and 87.3% at 5 years. Five-year LRFS was 82.6% in men and 93.3% in women (p = 0.027). After adjustment for gender, LRFS was better after primary treatment than after recurrence (hasard ratio HR, 2.91; 95% confidence interval, 1.06-8.03; p = 0.039). Five-year LRFS was 90.4% for BCC and 70.8% for SCC (p = 0.03). There were no Grade 3 complications. Conclusions: Low-dose rate brachytherapy offers good local control and cosmetic outcome in patients with periorificial skin carcinomas, with no Grade 3 complications. Brchytherapy is more efficient when used as primary treatment.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Model-Based Radiation Dose Correction for Yttrium-90 Microsphere Treatment of Liver Tumors With Central Necrosis

Purpose: The objectives of this study were to model and calculate the absorbed fraction {phi} of energy emitted from yttrium-90 ({sup 90}Y) microsphere treatment of necrotic liver tumors. Methods and Materials: The tumor necrosis model was proposed for the calculation of {phi} over the spherical shell region. Two approaches, the semianalytic method and the probabilistic method, were adopted. In the former method, the range--energy relationship and the sampling of electron paths were applied to calculate the energy deposition within the target region, using the straight-ahead and continuous-slowing-down approximation (CSDA) method. In the latter method, the Monte Carlo PENELOPE code was used to verify results from the first method. Results: The fraction of energy, {phi}, absorbed from {sup 90}Y by 1-cm thickness of tumor shell from microsphere distribution by CSDA with complete beta spectrum was 0.832 {+-} 0.001 and 0.833 {+-} 0.001 for smaller (r{sub T} = 5 cm) and larger (r{sub T} = 10 cm) tumors (where r is the radii of the tumor [T] and necrosis [N]). The fraction absorbed depended mainly on the thickness of the tumor necrosis configuration, rather than on tumor necrosis size. The maximal absorbed fraction {phi} that occurred in tumors without central necrosis for each size of tumor was different: 0.950 {+-} 0.000, and 0.975 {+-} 0.000 for smaller (r{sub T} = 5 cm) and larger (r{sub T} = 10 cm) tumors, respectively (p < 0.0001). Conclusions: The tumor necrosis model was developed for dose calculation of {sup 90}Y microsphere treatment of hepatic tumors with central necrosis. With this model, important information is provided regarding the absorbed fraction applicable to clinical {sup 90}Y microsphere treatment.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Disease Control and Ototoxicity Using Intensity-Modulated Radiation Therapy Tumor-Bed Boost for Medulloblastoma

Purpose: We previously reported excellent local control for treating medulloblastoma with a limited boost to the tumor bed. In order to decrease ototoxicity, we subsequently implemented a tumor-bed boost using intensity-modulated radiation therapy (IMRT), the clinical results of which we report here. Patients and Methods: A total of 33 patients with newly diagnosed medulloblastoma, 25 with standard risk, and 8 with high risk, were treated on an IMRT tumor-bed boost following craniospinal irradiation (CSI). Six standard-risk patients were treated with an institutional protocol with 18 Gy CSI in conjunction with intrathecal iodine-131-labeled monoclonal antibody. The majority of patients received concurrent vincristine and standard adjuvant chemotherapy. Pure-tone audiograms were graded according to National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. Results: Median age was 9 years old (range, 4-46 years old). Median follow-up was 63 months. Kaplan-Meier estimates of progression-free survival (PFS) and overall survival (OS) rates for standard-risk patients who received 23.4 or 36 Gy CSI (not including those who received 18 Gy CSI with radioimmunotherapy) were 81.4% and 88.4%, respectively, at 5 years; 5-year PFS and OS rates for high-risk patients were both 87.5%. There were no isolated posterior fossa failures outside of the boost volume. Posttreatment audiograms were available for 31 patients, of whom 6%, at a median follow-up of 19 months, had developed Grade 3 hearing loss. Conclusion: An IMRT tumor-bed boost results in excellent local control while delivering a low mean dose to the cochlea, resulting in a low rate of ototoxicity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Fossil and biogenic CO{sub 2} from waste incineration based on a yearlong radiocarbon study

Highlights: Black-Right-Pointing-Pointer Yearlong radiocarbon study on the share of biogenic CO{sub 2} from waste incineration. Black-Right-Pointing-Pointer Direct approach combining temporal integrating gas sampling and {sup 14}CO{sub 2} analysis by AMS. Black-Right-Pointing-Pointer Significant differences between incinerators with 43% and 54%Fos C. Black-Right-Pointing-Pointer No annual cycle of fossil CO{sub 2} for all, except one, of the included incinerators. - Abstract: We describe the first long-term implementation of the radiocarbon ({sup 14}C) method to study the share of biogenic (%Bio C) and fossil (%Fos C) carbon in combustion CO{sub 2}. At five Swiss incinerators, a total of 24 three-week measurement campaigns were performed over 1 year. Temporally averaged bag samples were analyzed for {sup 14}CO{sub 2} by accelerator mass spectrometry. Significant differences between the plants in the share of fossil CO{sub 2} were observed, with annual mean values from 43.4 {+-} 3.9% to 54.5 {+-} 3.1%. Variations can be explained by the waste composition of the respective plant. Based on our dataset, an average value of 48 {+-} 4%Fos C was determined for waste incineration in Switzerland. No clear annual trend in %Fos C was observed for four of the monitored incinerators, while one incinerator showed considerable variations, which are likely due to the separation and temporary storage of bulky goods.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

Spectroscopy of Neutron-rich Pu Nuclei

Spectroscopic studies of nuclei in the A{approx}250, Z{approx}100 region provide critical input to theoretical models that attempt to describe the structure and stability of the heaviest elements. We report here on new spectroscopic studies in the N = 150,151 nuclei {sup 244,245}Pu. (Z = 94). Excitations in these nuclei on the neutron-rich side of the valley of stability, accessed via inelastic and transfer reactions, complement fusion-evaporation studies of Z{>=}100 nuclei. States in {sup 244,245}Pu were populated using {sup 47}Ti and {sup 208}Pb beams incident on a {sup 244}Pu target, with delayed and prompt gamma rays detected by the Gammasphere array. The new results are discussed in the context of emerging systematics of one- and two-quasiparticle excitations in N{>=}150 nuclei.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2011

Laser spectroscopy-present and future at ISOLDE

Laser spectroscopy experiments at the ISOLDE facility have a venerable history which now spans more than 30 years. This period has seen the development of a remarkable variety of laser techniques in order to study rare isotopes far from stability, which include in-source, collinear and {beta}-NMR/{beta}-NQR spectroscopy. The propensity for innovation in laser spectroscopy at ISOLDE has continued in the last three years, helped in part by synergies with laboratories across Europe. Highlights of this work include bunched-beam spectroscopy of the neutron-rich copper and gallium isotope chains and collinear-anticollinear spectroscopy of the Be isotope chain. New ionization schemes have been developed for the Po atom crucial for the successful in-source laser spectroscopy campaign. The future HIE-ISOLDE facility will provide experimentalists with improved ion-beam quality, increased yields and a larger number of accessible elements. Several new experiments are now in preparation to maximise the reach of laser spectroscopy at HIE-ISOLDE, which include collinear resonance ionization spectroscopy and in-cooler optical pumping.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2011

The r-process nucleosynthesis during the decompression of neutronised matter

The rapid neutron-capture process, or r-process, is known to be of fundamental importance for explaining the origin of approximately half of the A>60 stable nuclei observed in nature. In recent years nuclear astrophysicists have developed more and more sophisticated r-process models, eagerly trying to add new astrophysical or nuclear physics ingredients to explain the solar system composition in a satisfactory way.We show here that the decompression of the neutron star matter may provide suitable conditions for a robust r-processing. After decompression, the inner crust material gives rise to an abundance distribution for A>130 nuclei similar to the one observed in the solar system. Similarly, the outer crust if heated at a temperature of about 8 10{sup 9} K before decompression is made of exotic neutron-rich nuclei with a mass distribution close to the 80{<=}A{<=}130 solar one. During the decompression, the free neutrons (initially liberated by the high temperatures) are re-captured leading to a final pattern similar to the solar system distribution.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2011

Fission-Fusion: A new reaction mechanism for nuclear astrophysics based on laser-ion acceleration

We propose to produce neutron-rich nuclei in the range of the astrophysical r-process around the waiting point N = 126 by fissioning a dense laser-accelerated thorium ion bunch in a thorium target (covered by a CH{sub 2} layer), where the light fission fragments of the beam fuse with the light fission fragments of the target. Via the 'hole-boring' mode of laser Radiation Pressure Acceleration using a high-intensity, short pulse laser, very efficiently bunches of {sup 232}Th with solid-state density can be generated from a Th target and a deuterated CD{sub 2} foil, both forming the production target assembly. Laser-accelerated Th ions with about 7 MeV/u will pass through a thin CH{sub 2} layer placed in front of a thicker second Th foil (both forming the reaction target) closely behind the production target and disintegrate into light and heavy fission fragments. In addition, light ions (d,C) from the CD{sub 2} layer of the production target will be accelerated as well, inducing the fission process of {sup 232}Th also in the second Th layer. The laser-accelerated ion bunches with solid-state density, which are about 10{sup 14} times more dense than classically accelerated ion bunches, allow for a high probability that generated fission products can fuse again. The high ion beam density may lead to a strong collective modification of the stopping power, leading to significant range and thus yield enhancement. Using a high-intensity laser as envisaged for the ELI-Nuclear Physics project in Bucharest (ELI-NP), order-of-magnitude estimates promise a fusion yield of about 10{sup 3} ions per laser pulse in the mass range of A = 180-190, thus enabling to approach the r-process waiting point at N = 126.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2011

Neutron-Rich {sup 62,64,64}Fe Show Enhanced Collectivity: The Washout of N = 40 in Terms of Experiment, Valence Proton Symmetry and Shell Model

Probing shell structure at a large neutron excess has been of particular interest in recent times. Neutron-rich nuclei between the proton shell closures Z = 20 and Z = 28 offer an exotic testing ground for shell evolution. The development of the N = 40gap between neutron fp and lg{sub 9/2} shells gives rise to highly interesting variations of collectivity for nuclei in this region. While {sup 68}Ni shows doubly magic properties in level energies and transition strengths, this was not observed in neighbouring nuclei. Especially neutron-rich Fe isotopes proved particularly resistant to calculational approaches using the canonical valence space (fpg) resulting in important deviations of the predicted collectivity. Only an inclusion of the d{sub 5/2}-orbital could solve the problem [1]. Hitherto no transition strengths for {sup 66}Fe have been reported. We determined B(E2,2{sup +}{sub 1}{yields}0{sup +}{sub 1}) values from lifetimes measured with the recoil distance Doppler-shift method using the Cologne plunger for radioactive beams at National Superconducting Cyclotron Laboratory at Michigan State University. Excited states were populated by projectile Coulomb excitation for {sup 62,64,66}Fe. The data show a rise in collectivity for Fe isotopes towards N = 40. Results [2] are interpreted by means of a modified version of the Valence Proton Symmetry [3] and compared to shell model calculations using a new effective interaction recently developed for the fpgd valence space [4].

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2011

Elastic scattering of Beryllium isotopes near the Coulomb barrier

In this contribution, results of experiments performed with the three Beryllium isotopes {sup 9,10,11}Be on a medium mass {sup 64}Zn target, at a center of mass energy of {approx_equal}1.4 the Coulomb barrier, will be discussed. Elastic scattering angular distributions have been measured for the {sup 9,10}Be reactions. In the {sup 11}Be case the quasielastic scattering angular distribution was obtained. In the halo nucleus case, the angular distribution exhibit a non-Fresnel-type pattern with a strong damping of the Coulomb-nuclear interference peak. Moreover, it is found that the total reaction cross-section for the halo nucleus induced collision is more than double the ones extracted in the collisions induced by the non-halo Beryllium isotopes. A large contribution to the total-reaction cross-section in the {sup 11}Be case could be attributed to transfer and/or break-up events.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗