55333370
The Annual Modulation Signature for Dark Matter: DAMA/LIBRA-Phase1 Results and Perspectives
The results obtained with the total exposure of 1.04 ton x yr collected by deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are summarized. The DAMA/LIBRA-phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton x yr, corresponding to 14 annual cycles) give evidence at 9.3 sigma C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radiopure NaI(Tl) target. The modulation amplitude of the single-hit events in the (2-6) keV energy interval is (0.0112 +/- 0.0012) cpd/kg/keV; the measured phase is (144 +/- 7) days and the measured period is (0.998 +/- 0.002) yr; values are in a good well in agreement with those expected for DM particles. No systematic or side reactions able to mimic the exploited DM signature have been found or suggested by anyone over more than a decade. Some of the perspectives of the presently running DAMA/LIBRA-phase2 are outlined.
124862840
DIRECT DETECTION OF DARK MATTER PARTICLES
117048271
First DAMA/LIBRA Results and Beyond
The DAMA project is an observatory for rare processes and it is operative deep underground at the Gran Sasso National Laboratory of the I.N.F.N. Its main apparatus is the DAMA/LIBRA set-up, consisting of ≃250 kg highly radiopure NaI(Tl) detectors. Its first results — obtained by exploiting over four annual cycles the model independent annual modulation signature for Dark Matter (DM) particles — confirm by those of the former DAMA/NaI, supporting the evidence for Dark Matter presence in the galactic halo at 8.2 σ C.L.. The DAMA/NaI and DAMA/LIBRA data, in fact, satisfy all the many peculiarities of the DM annual modulation signature. Neither systematic effects nor side reactions able to account for the observed modulation amplitude and to contemporaneously satisfy all the several requirements of the DM signature are available. Future perspectives are also addressed.
119701812
Signals from dark Universe: DAMA/LIBRA at LNGS
The DAMA/LIBRA set-up (about 250 kg highly radiopure NaI(Tl) sensitive mass) is running at the Gran Sasso National Laboratory of the INFN. The first DAMA/LIBRA results point out the presence of a dark matter particle component in the galactic halo, as well as the former DAMA/NaI set-up; cumulatively the data support such evidence at 8.2σ CL and satisfy all the peculiarities of the dark matter annual modulation signature.
17766827
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 (chi(0)) 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.
118311956
DAMA investigations on Dark Matter at Gran Sasso: results and perspectives
The DAMA/NaI experiment (≃ 100 kg highly radiopure NaI(Tl)) at the Gran Sasso National Laboratory of the I.N.F.N. had the unique feature to effectively investigate the presence of Dark Matter particles in the galactic halo by exploiting the model independent annual modulation signature. A total exposure of more than 105 kg × day, collected over seven annual cycles, has pointed out at 6.3 σ C.L. an effect which satisfies all the many peculiarities of the signature. Neither systematics nor side reactions able to account for the observed effect were found. No experiment whose result can be directly compared in a model independent way with the experimental one of DAMA/NaI is available so far. Searches in space experiments are not in contradiction with DAMA/NaI. Several (but still few with respect to the possibilities) corollary model dependent quests for the candidate particle have also been carried out; others are in progress. At present the second generation DAMA/LIBRA set‐up (≃ 250 kg highly radiopure NaI(...
125847794
Soft supersymmetry breaking and radiative Higgs signatures
I review our recent formulation of the minimal FCNC schemes of the soft supersymmetry breaking via the squark mass-terms and scalar trilinear interactions, where the large O(1) mixings among scalar-tops and -charms are found to be consistent with all existing theoretical and experimental bounds. Such a feature is demonstrated in a class of attractive new models with horizontal U(1) symmetry which also explain the observed quark-mass pattern and solve the SUSY μ-problem. The soft SUSY breaking induced radiative H±bc and h0tc Higgs couplings are analyzed and are shown to provide exciting new discovery Higgs signatures at the Tevatron and LHC.
209997379
Soft SUSY Breaking, Stop-Scharm Mixing and Higgs Signatures
119267356
Extending Higgs inflation with TeV scale new physics
Higgs inflation is among the most economical and predictive inflation models, although the original Higgs inflation requires tuning the Higgs or top mass away from its current experimental value by more than 2 sigma deviations, and generally gives a negligible tensor-to-scalar ratio r similar to 10(-3) (if away from the vicinity of critical point). In this work, we construct a minimal extension of Higgs inflation, by adding only two new weak-singlet particles at TeV scale, a vector-quark T and a real scalar S. The presence of singlets (T, S) significantly impact the renormalization group running of the Higgs boson self-coupling. With this, our model provides a wider range of the tensor-to-scalar ratio r = O(0.1) - O(10(-3)) consistent with the favored r values by either BICEP2 or Planck data, while keeping the successful prediction of the spectral index n(s) similar or equal to 0.96. It allows the Higgs and top masses to fully fit the collider measurements. We also discuss implications for searching the predicted TeV-scale vector-quark T and scalar S at the LHC and future high energy pp colliders.
55815188
Probing Gravitational Dark Matter
So far all evidences of dark matter (DM) come from astrophysical and cosmological observations, due to gravitational interactions of the DM. It is possible that the true DM particle in the universe joins gravitational interactions only, but nothing else. Such a Gravitational DM (GDM) may act as a weakly interacting massive particle (WIMP), which is conceptually simple and attractive. In this work, we explore this direction by constructing the simplest scalar GDM particle s . It is a Z 2 odd singlet under the standard model (SM) gauge group, and naturally joins the unique dimension-4 interaction with Ricci curvature, s 2 R , where s is the dimensionless nonminimal coupling. We demonstrate that this gravitational interaction s 2 R , together with Higgs-curvature nonminimal coupling term h H y HR , induces eective couplings between 2 and SM elds, and can account for the observed DM thermal relic abundance. We analyze the annihilation cross sections of GDM particles and derive the viable parameter space for realizing the DM thermal relic density. We further study the direct/indirect detections and the collider signatures of such a scalar GDM. These turn out to be highly predictive and testable.
888469
Ideal fermion delocalization in five dimensional gauge theories
We discuss ideal delocalization of fermions in a bulk $SU(2)\ifmmode\times\else\texttimes\fi{}SU(2)\ifmmode\times\else\texttimes\fi{}U(1)$ Higgsless model with a flat or warped extra dimension. So as to make an extra dimensional interpretation possible, both the weak and hypercharge properties of the fermions are delocalized, with the $U(1{)}_{Y}$ current of left-handed fermions being correlated with the $SU(2{)}_{W}$ current. We find that (to subleading order) ideal fermion delocalization yields vanishing precision electroweak corrections in this continuum model, as found in corresponding theory-space models based on deconstruction. In addition to explicit calculations, we present an intuitive argument for our results based on Georgi's spring analogy. We also discuss the conditions under which the essential features of an $SU(2)\ifmmode\times\else\texttimes\fi{}SU(2)\ifmmode\times\else\texttimes\fi{}U(1)$ bulk gauge theory can be captured by a simpler $SU(2)\ifmmode\times\else\texttimes\fi{}SU(2)$ model.