3,840 research outputs found
New model for the neutrino mass matrix
I suggest a model based on a softly broken symmetry L_e - L_mu - L_tau and on
Babu's mechanism for two-loops radiative generation of the neutrino masses. The
model predicts that one of the physical neutrinos (nu_3) is massless and that
its component along the nu_e direction (U_e3) is zero. Moreover, if the
soft-breaking term is assumed to be very small, then the vacuum oscillations of
nu_e have almost maximal amplitude and solve the solar-neutrino problem. New
scalars are predicted in the 10 TeV energy range, and a breakdown of e-mu-tau
universality should not be far from existing experimental bounds.Comment: 7 pages including 3 figure
Model for Small neutrino masses at the TeV Scale
We propose a model for neutrino mass generation in wich no physics beyond a
TeV is required. We extend the standard model by adding two charged singlet
fields with lepton number two. Dirac neutrino masses are
generated at the one loop level. Small left handed majorana neutrino masses can
be generated via the seesaw mechanism with right handed neutrino masses
are of order TeV scale.Comment: 13 pages, 2 figure
Protective or harmful? Exploring the ambivalent role of social identification as a moderator of intergroup stress in sojourners
Living outside one's home country may be stressful, and having strong social ties should help deal with this stress. However, social ties may be protective or harmful depending on whether the social group they evoke belongs to the host- or the home country context. The current study examines how social identification with different groups may either buffer or aggravate the negative effects of two stressors (perceived discrimination and symbolic threat) on sojourner adaptation. Two hundred and twenty international students sojourning in nine different countries responded to an online questionnaire. As expected, adaptation was negatively predicted by both stressors. Moreover, high identification with the group of international students attenuated the negative effects of perceived discrimination on psychological adaptation, while home country identification aggravated the negative effects of symbolic threat on sociocultural adaptation.info:eu-repo/semantics/acceptedVersio
The neglected C of intercultural relations. Cross-cultural adaptation shapes sojourner representations of locals
We investigated, by means of the Reverse Correlation Task (RCT), visual representations of the culturally dominating group of local people held by sojourners as a function of their degree of cross-cultural adaptation. In three studies, using three different methods (reduced RCT, full RCT, conceptual replication) with three independent samples of sojourners and seven independent samples of Portuguese and US-American raters, we gathered clear evidence that poor adaptation goes along with more negative representations of locals. This indicates that sojourner adaptation is reflected, at a social-cognitive level, in the valence of outgroup representationsinfo:eu-repo/semantics/publishedVersio
Giant Magnetic Moments of Nitrogen Stabilized Mn Clusters and Their Relevance to Ferromagnetism in Mn Doped GaN
Using first principles calculations based on density functional theory, we
show that the stability and magnetic properties of small Mn clusters can be
fundamentally altered by the presence of nitrogen. Not only are their binding
energies substantially enhanced, but also the coupling between the magnetic
moments at Mn sites remains ferromagnetic irrespective of their size or shape.
In addition, these nitrogen stabilized Mn clusters carry giant magnetic moments
ranging from 4 Bohr magnetons in MnN to 22 Bohr magnetons in Mn_5N. It is
suggested that the giant magnetic moments of Mn_xN clusters may play a key role
in the ferromagnetism of Mn doped GaN which exhibit a wide range (10K - 940K)
of Curie temperatures
Acculturation strategies among ethnic minority workers and the role of intercultural personality traits
International audienceIn an increasingly diverse work context minority employees strive to place and define themselves in terms of work and cultural identities. Based on Berry's acculturation model (1990), we defined and tested preferred acculturation strategies at work. It was predicted that , reflecting strong cultural identity maintenance combined with strong team identity adoption, is the most preferred strategy at work. The present study among non-Dutch employees working in The Netherlands ( = 108) showed that the dual identity is indeed preferred over strong team identity adoption, but solely among minority members who are emotionally stable. It is argued that these people are competent in dealing with the extra conflict and diversity-related stress that this acculturation strategy produces
Can the Zee Model Explain the Observed Neutrino Data?
The eigenvalues and mixing angles in the Zee model are investigated
parameter-independently. When we require |\Delta m^2_{12}/\Delta m^2_{23}| \ll
1 in order to understand the solar and atmospheric data simultaneously, the
only solution is one which gives bi-maximal mixing. It is pointed out that the
observed values \sin^2 2\theta_{solar} \simeq 0.66 in the MSW LMA solution
cannot be explained within the framework of the Zee model, because we derive a
severe constraint on the value of \sin^2 2 \theta_{solar}, \sin^2 2
\theta_{solar} \geq 1 -(1/16)(\Delta m^2_{solar}/\Delta m^2_{atm})^2.Comment: Latex file, 10 pages, 1 figure, explanations and references added,
typos corrected, to be published in Phys.Rev.
- …