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The energy levels and γ-ray decay scheme of the positive-parity states in the Tz=12 nucleus As67 have been studied by using the Ca40(Ar36,2αp)As67 reaction at a beam energy of 145 MeV. Two new band structures have been identified which can be connected to the previously known levels. The results for these bands are compared with configuration-dependent cranked Nilsson-Strutinsky calculations. The good level of agreement between theory and experiment suggests that these structures can be interpreted in terms of configurations that involve three g92 particles and that both possess noncollective terminating states.

The transitional nuclei Xe132 and Xe133 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+Pb208 MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the Xe136+Pt198 MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a Te130(α,xn)Xe134-xn fusion-evaporation reaction employing the HORUS γ-ray array at the University of Cologne. The high-spin level schemes are considerably extended above the Jπ=(7-) and (10+) isomers in Xe132 and above the 11/2- isomer in Xe133. The results are compared to the high-spin systematics of the Z=54 as well as the N=78 and N=79 chains. Furthermore, evidence is found for a long-lived (T1/2â‰1μs) isomer in Xe133 which closes a gap along the N=79 isotones. Shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.

The transitional nuclei Xe132 and Xe133 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+Pb208 MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the Xe136+Pt198 MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a Te130(α,xn)Xe134-xn fusion-evaporation reaction employing the HORUS γ-ray array at the University of Cologne. The high-spin level schemes are considerably extended above the Jπ=(7-) and (10+) isomers in Xe132 and above the 11/2- isomer in Xe133. The results are compared to the high-spin systematics of the Z=54 as well as the N=78 and N=79 chains. Furthermore, evidence is found for a long-lived (T1/2â‰1μs) isomer in Xe133 which closes a gap along the N=79 isotones. Shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.

The high-spin structures and isomers of the N=81 isotones Xe135 and Ba137 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+U238 and (ii) Xe136+Pb208 MNT reactions employing the high-resolution Advanced Gamma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (iii) in the Xe136+Pt198 MNT reaction employing the γ-ray array GAMMASPHERE in combination with the gas-detector array CHICO, and (iv) via a B11+Te130 fusion-evaporation reaction with the HORUS γ-ray array at the University of Cologne. The high-spin level schemesof Xe135 and Ba137 are considerably extended to higher energies. The 2058-keV (19/2-) state in Xe135 is identified as an isomer, closing a gap in the systematics along the N=81 isotones. Its half-life is measured to be 9.0(9) ns, corresponding to a reduced transition probability of B(E2,19/2-→15/2-)=0.52(6) W.u. The experimentally deduced reduced transition probabilities of the isomeric states are compared to shell-model predictions. Latest shell-model calculations reproduce the experimental findings generally well and provide guidance to the interpretation of the new levels.

The high-spin structures and isomers of the N=81 isotones Xe135 and Ba137 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+U238 and (ii) Xe136+Pb208 MNT reactions employing the high-resolution Advanced Gamma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (iii) in the Xe136+Pt198 MNT reaction employing the γ-ray array GAMMASPHERE in combination with the gas-detector array CHICO, and (iv) via a B11+Te130 fusion-evaporation reaction with the HORUS γ-ray array at the University of Cologne. The high-spin level schemesof Xe135 and Ba137 are considerably extended to higher energies. The 2058-keV (19/2-) state in Xe135 is identified as an isomer, closing a gap in the systematics along the N=81 isotones. Its half-life is measured to be 9.0(9) ns, corresponding to a reduced transition probability of B(E2,19/2-→15/2-)=0.52(6) W.u. The experimentally deduced reduced transition probabilities of the isomeric states are compared to shell-model predictions. Latest shell-model calculations reproduce the experimental findings generally well and provide guidance to the interpretation of the new levels.

Detailed spectroscopic information on the N∼82 nuclei is necessary to benchmark shell-model calculations in the region. The nuclear structure above long-lived isomers in Xe134 is investigated after multinucleon transfer (MNT) and actinide fission. Xenon-134 was populated as (i) a transfer product in Xe136+U238 and Xe136+Pb208 MNT reactions and (ii) as a fission product in the Xe136+U238 reaction employing the high-resolution Advanced Gamma Tracking Array (AGATA). Trajectory reconstruction has been applied for the complete identification of beamlike transfer products with the magnetic spectrometer PRISMA. The Xe136+Pt198 MNT reaction was studied with the γ-ray spectrometer GAMMASPHERE in combination with the gas detector array Compact Heavy Ion Counter (CHICO). Several high-spin states in Xe134 on top of the two long-lived isomers are discovered based on γγ-coincidence relationships and information on the γ-ray angular distributions as well as excitation energies from the total kinetic energy loss and fission fragments. The revised level scheme of Xe134 is extended up to an excitation energy of 5.832 MeV with tentative spin-parity assignments up to 16+. Previous assignments of states above the 7- isomer are revised. Latest shell-model calculations employing two different effective interactions reproduce the experimental findings and support the new spin and parity assignments.

The study of transfer reactions in inverse kinematics is a major focus of existing and future radioactive-ion-beam facilities. One of the obstacles in such measurements is poor Q-value resolution, often several hundred keV, which can prevent the extraction of useful information. At Argonne National Laboratory, it has recently been demonstrated that good Q-value resolution can be achieved by transporting the outgoing ions through a high-field solenoid, measuring their position as a function of energy. This provides several advantages over conventional Si arrays, such as large acceptance, good particle identification, and most importantly a Q-value resolution of better than 100 keV in most cases, including reactions with moderately heavy beams. In this paper, the concept of the solenoidal spectrometer, called HELIOS, will be discussed along with highlights of recent results.

The two-proton knockout reaction Be9(Ti54,Ca52+γ) has been studied at 72 MeV/nucleon. Besides the strong feeding of the Ca52 ground state, the only other sizeable cross section proceeds to a 3- level at 3.9 MeV. There is no measurable direct yield to the first excited 2+ state at 2.6 MeV. The results illustrate the potential of such direct reactions for exploring cross-shell proton excitations in neutron-rich nuclei and confirms the doubly-magic nature of Ca52. © 2006 The American Physical Society.

The odd-odd fp-shell nucleus Sc52 was investigated using in-beam γ-ray spectroscopy following secondary fragmentation of a V55 and Cr57 cocktail beam. Aside from the known γ-ray transition at 674(5) keV, a new decay at Eγ=212(3) keV was observed. It is attributed to the depopulation of a low-lying excited level. This new state is discussed in the framework of shell-model calculations with the GXPF1, GXPF1A, and KB3G effective interactions. These calculations are found to be fairly robust for the low-lying level scheme of Sc52 irrespective of the choice of the effective interaction. In addition, the frequency of spin values predicted by the shell model is successfully modeled by a spin distribution formulated in a statistical approach with an empirical, energy-independent spin-cutoff parameter. © 2006 The American Physical Society.

The near-yrast states of 42101Mo59 and 44103,4Ru59,60 have been studied following their population via heavy-ion multinucleon transfer reactions between a 136Xe beam and a thin, self-supporting 100Mo target. The ground state sequence in 104Ru can be understood as demonstrating a simple evolution from a quasi-vibrational structure at lower spins to statically deformed, quasi-rotational excitation involving the population of a pair of low-Ω h11/2 neutron orbitals. The effect of the decoupled h11/2 orbital on this vibration-to-rotational evolution is demonstrated by an extension of the "E-GOS" prescription to include odd-A nuclei. The experimental results are also compared with self-consistent Total Routhian Surface calculations which also highlight the polarising role of the highly aligned neutron h11/2 orbital in these nuclei.

The near-yrast states of 42101Mo59 and 44103,4Ru59,60 have been studied following their population via heavy-ion multinucleon transfer reactions between a 136Xe beam and a thin, self-supporting 100Mo target. The ground state sequence in 104Ru can be understood as demonstrating a simple evolution from a quasi-vibrational structure at lower spins to statically deformed, quasi-rotational excitation involving the population of a pair of low-Ω h11/2 neutron orbitals. The effect of the decoupled h11/2 orbital on this vibration-to-rotational evolution is demonstrated by an extension of the "E-GOS" prescription to include odd-A nuclei. The experimental results are also compared with self-consistent Total Routhian Surface calculations which also highlight the polarising role of the highly aligned neutron h11/2 orbital in these nuclei.

The 'Lyre' sign describes the characteristic splaying of the carotid artery bifurcation due to a carotid body tumour (paraganglioma) on conventional carotid angiography. In this pictorial review, we describe and illustrate two cases demonstrating the equivalent Lyre sign on multi-detector computed tomography (MDCT) and ultrasound resulting from carotid body tumour and extra-cranial internal carotid artery pseudoaneurysm. Both of these pathologies can manifest acutely and warrant accurate diagnosis to prevent potential catastrophic consequences. We also emphasise the added value of MDCT in making a definitive diagnosis and discuss other differential considerations splaying the carotid bifurcation. [ABSTRACT FROM AUTHOR]

In patients with suspected advanced ovarian carcinoma, a precise histological diagnosis is required before commencing neo-adjuvant chemotherapy. This study aims to determine the diagnostic accuracy and complication rate of percutaneous biopsies performed under ultrasound or computed tomography guidance. Between 2002 to 2007, 60 consecutive image-guided percutaneous biopsies were performed in patients with suspected ovarian cancer. The following variables were recorded: tissue biopsied, imaging technique, experience of operator, biopsy needle gauge, number of passes, complications, and final histology. Forty-seven patients had omental biopsies, 12 pelvic mass biopsies, and 1 para-aortic lymph node biopsy. Thirty-five biopsies were performed under ultrasound, 25 under computed tomography guidance. Biopsy needle gauges ranged from 14-20 swg with two to five passes for each patient. There were no complications. Histology was obtained in 52 (87%) patients. Percutaneous image-guided biopsy of peritoneal disease or pelvic mass is safe with high diagnostic accuracy. The large-gauge biopsy needle is as safe as the small gauge needle, but has the added value of obtaining tissue samples for immunohistochemistry and genomic studies. [ABSTRACT FROM AUTHOR]

The main objective of this study was to assess the quality of CT pulmonary angiography (CTPA) for suspected pulmonary embolus (PE) in the pregnant population. We retrospectively identified 40 consecutive pregnant patients who underwent CTPA from January 2005 to December 2006. Forty consecutive age-matched non-pregnant women were used as a control group. Studies were subjectively graded according to overall image quality by two readers in consensus, in randomised and blinded manner. Moreover, contrast enhancement of pulmonary arteries was subjectively and objectively evaluated. The proportion of sub-optimal studies was more than three times higher in the pregnant group (27.5%, n = 11) compared with the non-pregnant group (7.5%, n = 3; p = 0.015). Mean contrast enhancement was consistently higher in the non-pregnant group compared with pregnant group, both subjectively and objectively. The percentage of inadequately opacified vascular segments was more than two times higher in the pregnant group (28.7%, n = 264) than in the non-pregnant group (13.3%, n = 122; p = 0.0001). The incidence of sub-optimal CTPA studies is higher in pregnancy when compared with an age-matched non-pregnant control group. In addition to radiation issues, this should also be considered when implementing diagnostic strategies for suspected PE in pregnancy. [ABSTRACT FROM AUTHOR]

Acute idiopathic scrotal oedema is an uncommon cause of acute painless scrotal swelling that is usually seen in children. Traditionally, ultrasound has been used to help establish the diagnosis in the appropriate clinical setting. We report the MRI appearances of acute idiopathic scrotal oedema in a 51-year-old male with associated involvement of the penis. [ABSTRACT FROM AUTHOR]