A New Family of N-fold Supersymmetry: Type B

We construct a new family of N-fold supersymmetric systems which is referred to as ``type B''. A higher derivative representation of the N-fold supercharge for this new family is given by a deformation of the type A N-fold supercharge. By utilizing the same method as in the sl(2) construction of type A N-fold supersymmetry, we show that this family includes two of the quasi-solvable models of Post-Turbiner type.Comment: 12 pages, minor types corrected, references updated, DOI adde

RADIAL MOTIONS in DISK STARS: ELLIPTICITY or SECULAR FLOWS?

© 2016. The American Astronomical Society. All rights reserved.. Average stellar orbits of the Galactic disk may have some small intrinsic ellipticity which breaks the exact axisymmetry and there may also be some migration of stars inwards or outwards. Both phenomena can be detected through kinematic analyses. We use the red clump stars selected spectroscopically from the APO Galactic Evolution Experiment, with known distances and radial velocities, to measure the radial component of the Galactocentric velocities within 5 kpc < R < 16 kpc, , and within 20° from the Sun-Galactic center line. The average Galactocentric radial velocity is VR = (1.48 ± 0.35)[R(kpc) - (8.8 ± 2.7)] km s-1 outwards in the explored range, with a higher contribution from stars below the Galactic plane. Two possible explanations can be given for this result: (i) the mean orbit of the disk stars is intrinsically elliptical with a Galactocentric radial gradient of eccentricity around 0.01 kpc-1; or (ii) there is a net secular expansion of the disk, in which stars within R ≈ 9-11 kpc are migrating to the region R 11 kpc at the rate of ∼2 Mo yr-1, and stars with R ≲ 9 kpc are falling toward the center of the Galaxy. This migration ratio would be unattainable for a long time and should decelerate, otherwise the Galaxy would fade away in around 1 Gyr. At present, both hypotheses are speculative and one would need data on the Galactocentric radial velocities for other azimuths different to the center or anticenter in order to confirm one of the scenarios

Las imágenes de la historia en la obra de Stanley Kubrick.

Sin resume

The red supergiant population in the Perseus arm

We present a new catalogue of cool supergiants in a section of the Perseus arm, most of which had not been previously identified. To generate it, we have used a set of well-defined photometric criteria to select a large number of candidates (637) that were later observed at intermediate resolution in the the Infrared Calcium Triplet spectral range, using a long-slit spectrograph. To separate red supergiants from luminous red giants, we used a statistical method, developed in previous works and improved in the present paper. We present a method to assign probabilities of being a red supergiant to a given spectrum and use the properties of a population to generate clean samples, without contamination from lower-luminosity stars. We compare our identification with a classification done using classical criteria and discuss their respective efficiencies and contaminations as identification methods. We confirm that our method is as efficient at finding supergiants as the best classical methods, but with a far lower contamination by red giants than any other method. The result is a catalogue with 197 cool supergiants, 191 of which did not appear in previous lists of red supergiants. This is the largest coherent catalogue of cool supergiants in the Galaxy

Characterisation of red supergiants in the Gaia spectral range

The infrared Calcium Triplet and its nearby spectral region have been used for spectral and luminosity classification of late-type stars, but the samples of cool supergiants (CSGs) used have been very limited (in size, metallicity range, and spectral types covered). The spectral range of the Gaia Radial Velocity Spectrograph (RVS) covers most of this region but does not reach the main TiO bands in this region, whose depths define the M sequence. We study the behaviour of spectral features around the Calcium Triplet and develop effective criteria to identify and classify CSGs, comparing their efficiency with other methods previously proposed. We measure the main spectral features in a large sample (almost 600) of CSGs from three different galaxies, and we analyse their behaviour through a principal component analysis. Using the principal components, we develop an automatised method to differentiate CSGs from other bright late-type stars, and to classify them. The proposed method identifies a high fraction of the supergiants (SGs) in our test sample, which cover a wide metallicity range (SGs from the SMC, the LMC, and the Milky Way) and with spectral types from G0 up to late-M. In addition, it is capable to separate most of the non-SGs in the sample, identifying as SGs only a very small fraction of them. A comparison of this method with other previously proposed shows that it is more efficient and selects less interlopers. A way to automatically assign a spectral type to the SGs is also developed. We apply this study to spectra at the resolution and spectral range of the Gaia RVS, with a similar success rate. The method developed identifies and classifies CSGs in large samples, with high efficiency and low contamination, even in conditions of wide metallicity and spectral-type ranges

Homeownership as a Sign of Immigrants\u27 Consumer Acculturation: The Role of Region of Origin

One of the limitations highlighted by the consumer acculturation literature is the lack of empirical research to identify better constructs or indicators of consumer acculturation. In this article, the use of homeownership by immigrants in the host society is proposed as an indicator of advanced consumer acculturation. The decision to own a home by a minority group, such as immigrants, represents a key landmark in the process of adaptation to the new culture and a commitment with the host country\u27s values and culture. The empirical case used is the immigrant population of Spain. The sharp rise in its foreign-born population during the last decade and the significantly higher homeownership rates of natives in comparison with other countries makes the Spanish scenario a relevant case study. The results obtained show homeownership is linked to features associated with highly acculturated consumers. Moreover, the analysis conducted reveals important differences in the way immigrants from different origins advance in their consumer acculturation processes and suggest distinct approaches when marketing to these groups

Effect of adhesive thickness and concrete strength on FRP-Concrete Bonds

The use of fiber-reinforced polymer (FRP) composites for strengthening, repairing, or rehabilitating concrete structures has become more and more popular in the last 10 years. Irrespective of the type of strengthening used, design is conditioned, among others, by concrete-composite bond failure, normally attributed to stress at the interface between these two materials. Single shear, double shear, and notched beam tests are the bond tests most commonly used by the scientific community to estimate bond strength, effective length, and the bond stress-slip relationship. The present paper discusses the effect of concrete strength and adhesive thickness on the results of beam tests, which reproduce debonding conditions around bending cracks much more accurately. The bond stress-slip relationship was analyzed in a cross section near the inner edge, where stress was observed to concentrate. The ultimate load and the bond stress-slip relationship were visibly affected by concrete strength. Adhesive thickness, in turn, was found to have no significant impact on low-strength concrete but a somewhat greater effect on higher strength materials

Fluid--Gravity Correspondence under the presence of viscosity

The present work addresses the analogy between the speed of sound of a viscous, barotropic, and irrotational fluid and the equation of motion for a non--massive field in a curved manifold. It will be shown that the presence of viscosity implies the introduction, into the equation of motion of the gravitational analogue, of a source term which entails the flow of energy from the non--massive field to the curvature of the spacetime manifold. The stress-energy tensor is also computed and it is found not to be constant, which is consistent with such energy interchange

Estimation of the reference points for the different OMs in the Cod 3M MSE

This paper presents different methods to estimate the reference points (Blim, Bmsy and Fmsy) to be used in the 3M NAFO cod MSE. Reference points should be specific for each of the possible realities, what defines the different possible realities are the different OMs and, within each OM, the different iterations. The methods presented here try to estimate the reference points by iteration for the different OMs since it is assuming that the reference points will be interpreted as a characteristic of the “real” population. The results of some of the methods proposed to estimate the management reference points (limit and target) seem to be not consistent between them. The results show that in this case the proxy used as Fmsy (F30%SpR) seems quite reasonable