Chiral spin-orbital liquids with nodal lines

Strongly correlated materials with strong spin-orbit coupling hold promise for realizing topological phases with fractionalized excitations. Here we propose a chiral spin-orbital liquid as a stable phase of a realistic model for heavy-element double perovskites. This spin liquid state has Majorana fermion excitations with a gapless spectrum characterized by nodal lines along the edges of the Brillouin zone. We show that the nodal lines are topological defects of a non-Abelian Berry connection and that the system exhibits dispersing surface states. We discuss some experimental signatures of this state and compare them with properties of the spin liquid candidate Ba_2YMoO_6.Comment: 5 pages + supplementary materia

Enological potential of grapes produced in different periods in a tropical region of Northeast Brazil.

The Lower-Middle São Francisco river Valley is a new vitivinicultural region located in northeast Brazil, between 8° and 9° S latitude. ln this region 11's possible to have two-three harvests a year, mainly due to an annual average temperature of 26.4°C, with about 567 mm of rainfall between January and April, altitude of 350 m above sea leveI and use of drip irrigation. There is';a. continuous vegetative developrnent and grapevine growth occurs throughout the whole year. Grap~ composition can vary strongly according to harvest time of the year due to different climatic conditions. Wineries harvest grapes for winemaking between May and December. The aim of t4~~ study was to compare Tempranillo grapes composition harvested in two periods: June and December 2007, to best understand the influence ofharvest date on grape quality.Resumo

Enological potential of grapes produced in different periods in a tropical region of Northeast Brazil.

The lower-middle São Francisco river Valley is a new viticultural region located in northeast Brazil, between 8° and 90 Slatitude. ln this region it is possible to have two-three harvests a year, mainly due to an annual average temperature of 26.4°C, with about 567 mm of rainfall between Decem- berto March plus supplemental drip irrigation and altitude of 350m above sea leveI. A continuous vegetative development and grapevine growth occurs throughout the whole year. Grape composition can vary strongly according to harvest time of the year due to different c1imatic conditions.Suplemento S1

Estimation of phenolic compounds in tropical red wines from Northeast Brazil.

Suplemento S1

A Herschel Study of 24 micron-Selected AGNs and Their Host Galaxies

We present a sample of 290 24-micron-selected active galactic nuclei (AGNs) mostly at z ~ 0.3 -- 2.5, within 5.2 square degrees distributed as 25' X 25' fields around each of 30 galaxy clusters in the Local Cluster Substructure Survey (LoCuSS). The sample is nearly complete to 1 mJy at 24 microns, and has a rich multi-wavelength set of ancillary data; 162 are detected by Herschel. We use spectral templates for AGNs, stellar populations, and infrared emission by star forming galaxies to decompose the spectral energy distributions (SEDs) of these AGNs and their host galaxies, and estimate their star formation rates (SFRs), AGN luminosities, and host galaxy stellar masses. The set of templates is relatively simple: a standard Type-1 quasar template; another for the photospheric output of the stellar population; and a far infrared star-forming template. For the Type-2 AGN SEDs, we substitute templates including internal obscuration, and some Type-1 objects require a warm component (T > 50 K). The individually Herschel- detected Type-1 AGNs and a subset of 17 Type-2 ones typically have luminosities > 10^{45} ergs/s, and supermassive black holes of ~ 3 X 10^8 Msun emitting at ~ 10% of the Eddington rate. We find them in about twice the numbers of AGN identified in SDSS data in the same fields, i.e., they represent typical high luminosity AGN, not an infrared-selected minority. These AGNs and their host galaxies are studied further in an accompanying paper

All-sky Relative Opacity Mapping Using Night Time Panoramic Images

An all-sky cloud monitoring system that generates relative opacity maps over many of the world's premier astronomical observatories is described. Photometric measurements of numerous background stars are combined with simultaneous sky brightness measurements to differentiate thin clouds from sky glow sources such as air glow and zodiacal light. The system takes a continuous pipeline of all-sky images, and compares them to canonical images taken on other nights at the same sidereal time. Data interpolation then yields transmission maps covering almost the entire sky. An implementation of this system is currently operating through the Night Sky Live network of CONCAM3s located at Cerro Pachon (Chile), Mauna Kea (Hawaii), Haleakala (Hawaii), SALT (South Africa) and the Canary Islands (Northwestern Africa).Comment: Accepted for publication in PAS

Características sensoriais de vinhos tropicais.

Resumo também em inglês: Sensorial characteristics of tropical wines

Magnetically-controlled impurities in quantum wires with strong Rashba coupling

We investigate the effect of strong spin-orbit interaction on the electronic transport through non-magnetic impurities in one-dimensional systems. When a perpendicular magnetic field is applied, the electron spin polarization becomes momentum-dependent and spin-flip scattering appears, to first order in the applied field, in addition to the usual potential scattering. We analyze a situation in which, by tuning the Fermi level and the Rashba coupling, the magnetic field can suppress the potential scattering. This mechanism should give rise to a significant negative magnetoresistance in the limit of large barriers.Comment: 4 pages, 2 figure

Avaliação da composição da uva e do vinho varietal 'Tempranillo' segundo a época de produção, na região do Vale do Submédio São Francisco.

O Vale do Submédio do São Francisco é a segunda região produtora de vinhos finos do Brasil, sendo responsável por 15% da produção nacional, com oito milhões de litros/ano