Measurement of Excited Hyperons in Photoproduction at CLAS

Measurement results of photoproduced excited hyperon states using the CLAS detector at Jefferson Lab are shown. The invariant mass distribution of the Lambda(1405) has recently been shown to be different for each of the three Sigma pi channels that it decays to, showing that there is prominent interference between the isospin I=0 and I=1 isospin amplitudes. Measurements of the differential and total cross sections of the three hyperons Lambda(1405), Sigma0(1385), and Lambda(1520) are presented and compared. Prospects of future studies using a 12 GeV beam with the GlueX detector are briefly given.Comment: 6 pages, 4 figures, proceedings for THE 9th International workshop on the Physics of Excited Nucleons, "NSTAR2013" 9th International workshop on the Physics of Excited Nucleon

Properties of the Lambda(1405) Measured at CLAS

The nature of the Lambda(1405), and its place in the baryon spectrum has remained uncertain for decades. Theoretical studies have shown that it may possess strong dynamical components which are not seen in other well-known baryons. Using the CLAS detector system in Hall B at Jefferson Lab, we have measured the photoproduction reaction gamma+p->K+ Lambda(1405) with high statistics and over different Sigma pi decay channels. The reconstructed invariant mass distribution (lineshape) has been measured, as well as the differential cross sections for the Lambda(1405), Sigma(1385), and Lambda(1520). Our analysis method is discussed and our near-final results for the Lambda(1405) lineshape and differential cross section are presented.Comment: Proceedings for The 8th International Workshop on the Physics of Excited Nucleons (NSTAR11), May 17-20, 2011 held at Thomas Jefferson National Accelerator Facility Newport News, Virginia US

Intersections of ultracold atomic polarons and nuclear clusters: How is a chart of nuclides modified in dilute neutron matter?

Neutron star observations, as well as experiments on neutron-rich nuclei, used to motivate one to look at degenerate nuclear matter from its extreme, namely, pure neutron matter. As an important next step, impurities and clusters in dilute neutron matter have attracted special attention. In this paper, we review in-medium properties of these objects on the basis of the physics of polarons, which have been recently realized in ultracold atomic experiments. We discuss how such atomic and nuclear systems are related to each other in terms of polarons. In addition to the interdisciplinary understanding of in-medium nuclear clusters, it is shown that the quasiparticle energy of a single proton in neutron matter is associated with the symmetry energy, implying a novel route toward the nuclear equation of state from the neutron-rich side.Comment: 28 pages, 2 figure

A case of primary mucosa-associated lymphoid tissue lymphoma of the prostate

We report a case of primary mucosa-associated lymphoid tissue (MALT) lymphoma of the prostate. A 67-year-old man presented with urinary obstruction and an elevated prostate-specific antigen (PSA) level. A physical examination revealed mild prostate enlargement and no lymphadenopathy. A needle biopsy and immunohistochemical studies of the prostate were performed, which revealed marginal zone B-cell MALT-type lymphoma. A bone marrow aspiration and biopsy did not show involvement by lymphoma. Magnetic resonance imaging (MRI) of the abdomen and the pelvis revealed no lymphadenopathy or ascites. There was no involvement of other sites by lymphoma. The patient was diagnosed and staged as extranodal marginal zone B-cell MALT-type lymphoma of the prostate, low grade and stage I. The patient received external beam radiation therapy to the prostate with a total dose of 3600cGy in 22 fractions, and became free of disease within the following 15 months

Discovery of chemosynthesis-based association on the Cretaceous basal leatherback sea turtle from Japan

We report a Late Cretaceous chemosynthetic community fueled by decomposing basal leatherback sea turtle on the ocean floor in the western Pacific. The fossil association representing this community has been recovered from the matrix of a concretion containing a single carapace of Mesodermochelys sp. from Late Cretaceous outer shelf to upper slope deposit of northern Hokkaido, Japan. The carapace displays boreholes most likely performed by boring bivalves, and is associated with molluscan shells, mainly Provanna cf. nakagawensis and Thyasira tanabei. Since this association is similar to fauna already known from Late Cretaceous hydrocarbon seeps, sunken wood, and plesiosaur-falls in Hokkaido, it is suggested that all types of chemosynthesis-based communities in the Late Cretaceous of western Pacific may have belonged to the same regional pool of animals and were not yet fully differentiated into three independent types of communities as it is known today. This finding also indicates that the sulfophilic stage of the vertebrate-fall communities was supported not only by plesiosaur carcasses, which were previously reported, but also by sea turtle carcasses. It highlights the possibility of surviving vertebrate-fall communities through the end-Cretaceous mass extinction event on carcasses of sea turtles which are the only large marine vertebrates surviving this event