1,157 research outputs found
X-ray view of four high-luminosity Swift/BAT AGN: Unveiling obscuration and reflection with Suzaku
The Swift/BAT nine-month survey observed 153 AGN, all with ultra-hard X-ray
BAT fluxes in excess of 10^-11 erg cm^-2 s^-1 and an average redshift of 0.03.
Among them, four of the most luminous BAT AGN (44.73 < Log L(BAT) < 45.31) were
selected as targets of Suzaku follow-up observations: J2246.0+3941 (3C 452),
J0407.4+0339 (3C 105), J0318.7+6828, and J0918.5+0425. The column density,
scattered/reflected emission, the properties of the Fe K line, and a possible
variability are fully analyzed. For the latter, the spectral properties from
Chandra, XMM-Newton and Swift/XRT public observations were compared with the
present Suzaku analysis. Of our sample, 3C 452 is the only certain
Compton-thick AGN candidate because of i) the high absorption and strong
Compton reflection; ii) the lack of variability; iii) the "buried" nature, i.e.
the low scattering fraction (<0.5%) and the extremely low relative [OIII]
luminosity. In contrast 3C 105 is not reflection-dominated, despite the
comparable column density, X-ray luminosity and radio morphology, but shows a
strong long-term variability in flux and scattering fraction, consistent with
the soft emission being scattered from a distant region (e.g., the narrow
emission line region). The sample presents high (>100) X-to-[OIII] luminosity
ratios, confirming the [OIII] luminosity to be affected by residual extinction
in presence of mild absorption, especially for "buried" AGN such as 3C 452.
Three of our targets are powerful FRII radio galaxies, making them the most
luminous and absorbed AGN of the BAT Seyfert survey despite the inversely
proportional N_H - L_X relation.Comment: A&A paper in press, 17 page
Methodological and terminological issues in animal-assisted interventions: An umbrella review of systematic reviews
Recently, animal-assisted interventions (AAIs), which are defined as psychological, educational, and rehabilitation support activities, have become widespread in different contexts. For many years, they have been a subject of interest in the international scientific community and are at the center of an important discussion regarding their effectiveness and the most appropriate practices for their realization. We carried out an umbrella review (UR) of systematic reviews (SRs), created for the purpose of exploring the literature and aimed at deepening the terminological and methodological aspects of AAIs. It is created by exploring the online databases PubMed, Google Scholar, and Cochrane Library. The SRs present in the high-impact indexed search engines Web of Sciences and Scopus are selected. After screening, we selected 15 SRs that met the inclusion criteria. All papers complained of the poor quality of AAIs; some considered articles containing interventions that did not always correspond to the terminology they have explored and whose operating practices were not always comparable. This stresses the need for the development and consequent diffusion of not only operational protocols, but also research protocols which provide for the homogeneous use of universally recognized terminologies, thus facilitating the study, deepening, and comparison between the numerous experiences described
Photoassociation inside an optical dipole trap: absolute rate coefficients and Franck-Condon factors
We present quantitative measurements of the photoassociation of cesium
molecules inside a far-detuned optical dipole trap. A model of the trap
depletion dynamics is derived which allows to extract absolute photoassociation
rate coefficients for the initial single-photon photoassociation step from
measured trap-loss spectra. The sensitivity of this approach is demonstrated by
measuring the Franck-Condon modulation of the weak photoassociation transitions
into the low vibrational levels of the outer well of the 0g- state that
correlates to the 6s+6p3/2 asymptote. The measurements are compared to
theoretical predictions. In a magneto-optical trap these transitions have
previously only been observed indirectly through ionization of ground state
molecules
Yield and Forage Quality in Alfalfa-Weeping Lovegrass Mixtures
Little is known about the relative performance of weeping lovegrass in mixtures with alfalfa. Our objective was to compare the productivity and forage quality of monocultures and binary mixtures of the species. Mixtures always gave higher yields than any of the monocultures and the highest was obtained in the mixture with the largest proportion of alfalfa. In the second year weeping lovegrass N concentration in the mixtures were higher than in monoculture. Weeping lovegrass did not affect the alfalfa N concentration. There was not differences in the NDF, for between these species
Sustainable landscape in arid zones : useful ornamental xeric species
Se analiza el valor económico,
ecológico y paisajístico de especies vegetales,
pertenecientes a la flora espontánea de
Mendoza (Argentina), resistentes a la sequía
y que pueden alcanzar porte arbóreo. Su empleo
ahorra agua de riego en espacios verdes
ornamentales y de protección ambiental.
Se sugiere medidas de conservación de
las especies espontáneas más útiles
paisajísticamente, así como normas generales
sobre métodos de plantación y mantenimiento.
Se recomiendan especies leñosas
espontáneas de la provincia, de bajo requerimiento
hídrico, utilizables paisajísticamente.This paper analyzes the economic,
ecological and landscape value of drought
resistant species from the spontaneous flora
of Mendoza (Argentina). Some of such
species could reach tree size and its use
might save the irrigation water used for ornamental
and environmental protection
areas.
Actions to protect the most useful
spontaneous species, as well as general
rules for plantation and maintenance are
suggested. Spontaneous wooden species of
low water requirements, to use in different
landscape objectives, are recommended.Fil: Codina, Ramón A..
Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Producción AgropecuariaFil: Manzano, Enrique R..
Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Producción AgropecuariaFil: Carrieri, Sergio A..
Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Producción AgropecuariaFil: Fioretti, Sonia B..
Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Producción Agropecuari
Data model issues in the Cherenkov Telescope Array project
The planned Cherenkov Telescope Array (CTA), a future ground-based
Very-High-Energy (VHE) gamma-ray observatory, will be the largest project of
its kind. It aims to provide an order of magnitude increase in sensitivity
compared to currently operating VHE experiments and open access to guest
observers. These features, together with the thirty years lifetime planned for
the installation, impose severe constraints on the data model currently being
developed for the project.
In this contribution we analyze the challenges faced by the CTA data model
development and present the requirements imposed to face them. While the full
data model is still not completed we show the organization of the work, status
of the design, and an overview of the prototyping efforts carried out so far.
We also show examples of specific aspects of the data model currently under
development.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherlands. All CTA contributions at
arXiv:1508.0589
Formation of ultracold LiCs molecules
We present the first observation of ultracold LiCs molecules. The molecules
are formed in a two-species magneto-optical trap and detected by two-photon
ionization and time-of-flight mass spectrometry. The production rate
coefficient is found to be in the range 10^{-18}\unit{cm^3s^{-1}} to
10^{-16}\unit{cm^3s^{-1}}, at least an order of magnitude smaller than for
other heteronuclear diatomic molecules directly formed in a magneto-optical
trap.Comment: 8 pages, 2 figure
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