225 research outputs found
Dirac Gauginos in General Gauge Mediation
We extend the formulation by Meade, Seiberg and Shih of general gauge
mediation of supersymmetry breaking to include Dirac masses for the gauginos.
These appear through mixing of the visible sector gauginos with additional
states in adjoint representations. We illustrate the method by reproducing the
existing results in the literature for the gaugino and sfermion masses when
preserving R-symmetry. We then explain how the generation of same sign masses
for the two propagating degrees of freedom in the adjoint scalars can be
achieved. We end by commenting on the use of the formalism for describing U(1)
mixing.Comment: 22 pages, no figures. V2: minor corrections
First identification of excited states in Ba 117 using the recoil- ÎČ -delayed proton tagging technique
Excited states have been observed for the first time in the neutron-deficient nucleus Ba117 using the recoil-decay tagging technique following the heavy-ion fusion-evaporation reaction Zn64(Ni58, 2p3n)Ba117. Prompt Îł rays have been assigned to Ba117 through correlations with ÎČ-delayed protons following the decay of A=117 recoils. Through the analysis of the Îł-Îł coincidence relationships, a high-spin level scheme consisting of two bands has been established in Ba117. Based on the systematics of the level spacings in the neighboring barium isotopes, the two bands are proposed to have Îœh11/2[532]5/2- and Îœd5/2[413]5/2+ configurations, respectively. The observed band-crossing properties are interpreted in the framework of cranked shell model
Quadrupole and octupole collectivity in Ba 143
The neutron-rich barium nuclei have been the subject of intense interest due to the enhanced octupole correlations they are predicted to exhibit. The observation of enhanced octupole collectivity in Ba144,146 as measured in sub-barrier Coulomb excitation, consistent with static octupole deformation, has further heightened this interest. In the present work, these studies are extended to the neighboring odd-mass Ba143 to investigate the interplay between single-particle and collective octupole degrees of freedom. A new measurement of the first 92 - state lifetime is also presented. Reflection-Asymmetric Triaxial Particle Rotor Model calculations indicate that the negative-parity bands in Ba143 can be understood as a decoupled structure of Îœh9/2 parentage, while the positive-parity bands are built on a decoupled octupole phonon. No evidence for E3 excitation is observed in this work, but an upper limit is placed on the E3 matrix element to the lowest octupole band
Examination of the low-energy enhancement of the Îł -ray strength function of Fe 56
A model-independent technique was used to determine the Îł-ray strength function (ÎłSF) of Fe56 down to Îł-ray energies less than 1 MeV for the first time with GRETINA using the (p,pâČ) reaction at 16 MeV. No difference was observed in the energy dependence of the ÎłSF built on 2+ and 4+ final states, supporting the Brink hypothesis. In addition, angular distribution and polarization measurements were performed. The angular distributions are consistent with dipole radiation. The polarization results show a small bias towards magnetic character in the region of the enhancement
Examination of the low-energy enhancement of the Îł -ray strength function of Fe 56
A model-independent technique was used to determine the Îł-ray strength function (ÎłSF) of Fe56 down to Îł-ray energies less than 1 MeV for the first time with GRETINA using the (p,pâČ) reaction at 16 MeV. No difference was observed in the energy dependence of the ÎłSF built on 2+ and 4+ final states, supporting the Brink hypothesis. In addition, angular distribution and polarization measurements were performed. The angular distributions are consistent with dipole radiation. The polarization results show a small bias towards magnetic character in the region of the enhancement
Paleobiology of titanosaurs: reproduction, development, histology, pneumaticity, locomotion and neuroanatomy from the South American fossil record
Fil: GarcĂa, Rodolfo A.. Instituto de InvestigaciĂłn en PaleobiologĂa y GeologĂa. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Salgado, Leonardo. Instituto de InvestigaciĂłn en PaleobiologĂa y GeologĂa. General Roca. RĂo Negro; ArgentinaFil: FernĂĄndez, Mariela. Inibioma-Centro Regional Universitario Bariloche. Bariloche. RĂo Negro; ArgentinaFil: Cerda, Ignacio A.. Instituto de InvestigaciĂłn en PaleobiologĂa y GeologĂa. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Carabajal, Ariana Paulina. Museo Carmen Funes. Plaza Huincul. NeuquĂ©n; ArgentinaFil: Otero, Alejandro. Museo de La Plata. Universidad Nacional de La Plata; ArgentinaFil: Coria, Rodolfo A.. Instituto de PaleobiologĂa y GeologĂa. Universidad Nacional de RĂo Negro. NeuquĂ©n; ArgentinaFil: Fiorelli, Lucas E.. Centro Regional de Investigaciones CientĂficas y Transferencia TecnolĂłgica. Anillaco. La Rioja; Argentin
The APEX Large CO Heterodyne Orion Legacy Survey (ALCOHOLS): I. Survey overview
Context: The Orion molecular cloud complex harbours the nearest Giant Molecular Clouds (GMCs) and the nearest site of high-mass star formation. Its young star and protostar populations are thoroughly characterized. The region is therefore a prime target for the study of star formation. Aims: Here, we verify the performance of the SuperCAM 64 pixel heterodyne array on the Atacama Pathfinder Experiment (APEX). We give a descriptive overview of a set of wide-field CO(3-2) spectral line cubes obtained towards the Orion GMC complex, aimed at characterizing the dynamics and structure of the extended molecular gas in diverse regions of the clouds, ranging from very active sites of clustered star formation in Orion B to comparatively quiet regions in southern Orion A. In a future publication, we will characterize the full population of protostellar outflows and their feedback over an entire GMC. Methods: We present a 2.7 square degree (130 pc2) mapping survey in the 12CO(3-2) transition, obtained using SuperCAM on APEX at an angular resolution of 1900 (7600 AU or 0.037 pc at a distance of 400 pc), covering the main sites of star formation in the Orion B cloud (L 1622, NGC 2071, NGC 2068, Ori B9, NGC 2024, and NGC 2023), and a large patch in the southern part of the L 1641 cloud in Orion A. Results: We describe CO integrated line emission and line moment maps and position-velocity diagrams for all survey fields and discuss a few subregions in some detail. Evidence for expanding bubbles is seen with lines splitting into double components, often in areas of optical nebulosities, most prominently in the NGC 2024 H ii region, where we argue that the bulk of the molecular gas is in the foreground of the H ii region. High CO(3-2)/CO(1-0) line ratios reveal warm CO along the western edge of the Orion B cloud in the NGC 2023/NGC 2024 region facing the IC 434 H ii region. We see multiple, well separated radial velocity cloud components towards several fields and propose that L 1641-S consists of a sequence of clouds at increasingly larger distances. We find a small, seemingly spherical cloud, which we term âCow Nebulaâ globule, north of NGC 2071. We confirm that we can trace high velocity line wings out to the âextremely high velocityâ regime in protostellar molecular outflows for the NGC 2071-IR outflow and the NGC 2024 CO jet, and identify the protostellar dust core FIR4 (rather than FIR5) as the true driving source of the NGC 2024 monopolar outflow
Mating behavior and female accompaniment in the whiptail lizard Cnemidophorus ocellifer (Squamata, Teiidae) in the Caatinga region of northeastern Brazil
Search for dark matter produced in association with a hadronically decaying vector boson in pp collisions at sqrt (s) = 13 TeV with the ATLAS detector
A search is presented for dark matter produced in association with a hadronically decaying W or Z boson using 3.2 fbâ1 of pp collisions at View the MathML sources=13 TeV recorded by the ATLAS detector at the Large Hadron Collider. Events with a hadronic jet compatible with a W or Z boson and with large missing transverse momentum are analysed. The data are consistent with the Standard Model predictions and are interpreted in terms of both an effective field theory and a simplified model containing dark matter
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