638 research outputs found
DAMA/NaI results
The DAMA/NaI set-up of the DAMA experiment has been operative during seven
annual cycles and has investigated several rare processes. In particular, it
has been realised in order to investigate the model independent annual
modulation signature for Dark Matter particles in the galactic halo. With the
total exposure collected in the seven annual cycles (107731 kg day) a model
independent evidence for the presence of a Dark Matter particle component in
the galactic halo has been pointed out at 6.3 sigma C.L.. Some of the many
possible corollary model dependent quests for the candidate particle have been
presented as well.Comment: Contributed paper to the Rencontres de Moriond "Electroweak
Interactions and Unified Theories", La Thuile, Aosta Valley, Italy, March
200
A novel integral representation for the Adler function
New integral representations for the Adler D-function and the R-ratio of the
electron-positron annihilation into hadrons are derived in the general
framework of the analytic approach to QCD. These representations capture the
nonperturbative information encoded in the dispersion relation for the
D-function, the effects due to the interrelation between spacelike and timelike
domains, and the effects due to the nonvanishing pion mass. The latter plays a
crucial role in this analysis, forcing the Adler function to vanish in the
infrared limit. Within the developed approach the D-function is calculated by
employing its perturbative approximation as the only additional input. The
obtained result is found to be in reasonable agreement with the experimental
prediction for the Adler function in the entire range of momenta .Comment: 11 pages, 3 figure
QTLs for Morphogenetic Traits in Medicago Truncatula
Plant morphogenesis that includes growth, development and flowering date, drives a large number of agronomical important traits in both grain and forage crops. Quantitative trait locus (QTL) mapping is a way to locate zones of the genome that are involved in the variations observed in a segregating population. Co-location of QTLs and candidate genes is an indication of the involvement of the genes in the variation. The objective of this study was to analyse segregation of aerial morphogenetic traits in a mapping population of recombinant inbred lines of the model legume species M. truncatula , to locate QTLs and candidate genes
Investigating halo substructures with annual modulation signature
Galaxy hierarchical formation theories, numerical simulations, the discovery
of the Sagittarius Dwarf Elliptical Galaxy (SagDEG) in 1994 and more recent
investigations suggest that the dark halo of the Milky Way can have a rich
phenomenology containing non thermalized substructures. In the present
preliminary study, we investigate the case of the SagDEG (the best known
satellite galaxy in the Milky Way crossing the solar neighbourhood) analyzing
the consequences of its dark matter stream contribution to the galactic halo on
the basis of the DAMA/NaI annual modulation data. The present analysis is
restricted to some WIMP candidates and to some of the astrophysical, nuclear
and particle Physics scenarios. Other candidates such as e.g. the light bosonic
ones, we discussed elsewhere, and other non thermalized substructures are not
yet addressed here.Comment: 17 pages, 10 figures, to appear in Eur. Phys. J.
Investigating pseudoscalar and scalar dark matter
In this paper another class of Dark Matter candidate particles: the
pseudoscalar and scalar light bosonic candidates, is discussed. Particular care
is devoted to the study of the processes for their detection (which only
involves electrons and photons/X-rays) in a suitable underground experimental
set-up. For this purpose the needed calculations are developed and various
related aspects and phenomenologies are discussed. In particular, it is shown
that - in addition to the WIMP cases already discussed elsewhere - there is
also possibility for a bosonic candidate to account for the 6.3 sigma C.L.
model independent evidence for the presence of a particle DM component in the
galactic halo observed by DAMA/NaI. Allowed regions in these scenarios are
presented also paying particular care on the cosmological interest of the
bosonic candidate.Comment: 23 pages, 6 figures, 1 table, Int. J. Mod. Phys. A (in press
Investigating electron interacting dark matter
Some extensions of the Standard Model provide Dark Matter candidate particles
which can have a dominant coupling with the lepton sector of the ordinary
matter. Thus, such Dark Matter candidate particles () can be directly
detected only through their interaction with electrons in the detectors of a
suitable experiment, while they are lost by experiments based on the rejection
of the electromagnetic component of the experimental counting rate. These
candidates can also offer a possible source of the 511 keV photons observed
from the galactic bulge. In this paper this scenario is investigated. Some
theoretical arguments are developed and related phenomenological aspects are
discussed. Allowed intervals and regions for the characteristic
phenomenological parameters of the considered model and of the possible
mediator of the interaction are also derived considering the DAMA/NaI data.Comment: 16 pages, 6 figures. Accepted for publication in PRD. One typo
correcte
The DAMA/LIBRA apparatus
The 250 kg highly radiopure NaI(Tl) DAMA/LIBRA apparatus, running at
the Gran Sasso National Laboratory (LNGS) of the I.N.F.N., is described.Comment: 37 pages, 27 figure
Sincronização do estro de cabras com protocolos de curta duração utilizando CIDR-G e esponja intravaginal.
- …