15785910
The DAMA/LIBRA apparatus
The similar or equal to 250 kg highly radiopure NaI(Tl) DAMA/LIBRA apparatus, running at the Gran Sasso National Laboratory (LNGS) of the INFN, is described. (C) 2008 Elsevier B.V. All rights reserved.
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.
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.
124862840
DIRECT DETECTION OF DARK MATTER PARTICLES
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.
17529257
Direct detection of dark-matter particles
In this conference the model-independent result on the presence of 
dark-matter particles in the galactic halo obtained over seven annual cycles by the 
 100 kg highly radiopure NaI(Tl) DAMA/NaI has been presented and several corollary 
investigations have also been discussed. More recently the model-independent 
result obtained over the first four annual cycles by the second generation 250 kg 
highly radiopure NaI(Tl) DAMA/LIBRA set-up at the Gran Sasso National Laboratory 
of the INFN has also been released. Both the experiments have the unique 
feature to effectively investigate the presence of dark-matter particles in the galactic 
halo by exploiting the model-independent annual modulation signature. The 
data collected by the two experiments over eleven annual cycles for a total exposure 
of 0.82 ton × y have pointed out at 8.2σ CL a positive result; several corollary 
model-dependent quests for the candidate particle(s) and related astrophysical, nuclear 
and particle physics scenarios are under updating. The future experimental 
activity can give rise to many new interesting results.
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.
119074305
LHC Higgs signatures from topflavor seesaw mechanism
We study LHC Higgs signatures from topflavor seesaw realization of electroweak symmetry breaking with a minimal gauge extension SU(2) circle times SU(2) circle times U(1). This elegant renormalizable construction singles out top quark sector (instead of all other light fermions) to join the new SU(2) gauge force. It predicts extra vector-like spectator quarks (T, B), new gauge bosons (W', Z'), and a pair of neutral Higgs bosons (h, H). We demonstrate that for the lighter Higgs boson h of mass 125 GeV, this model predicts modified Higgs signal rates in h -> gamma gamma, WW*, ZZ* channels via gluon fusions, in h -> tau(tau) over bar mode via vector boson fusions, and in h -> b (b) over bar mode via gauge boson associate productions. We perform a global fit for our theory by including both direct search data (LHC and Tevatron) and indirect precision constraints. We further analyze the LHC discovery potential for detecting the heavier Higgs state H. (C) 2013 Elsevier B.V. All rights reserved.
1310354
Unitarity of compactified five-dimensional Yang-Mills theory
Abstract Compactified five-dimensional Yang–Mills theory results in an effective four-dimensional theory with a Kaluza–Klein (KK) tower of massive vector bosons. We explicitly demonstrate that the scattering of the massive vector bosons is unitary at tree-level for low energies, and analyze the relationship between the unitarity violation scale in the KK theory and the nonrenormalizability scale in the five-dimensional gauge theory. In the compactified theory, low-energy unitarity is ensured through an interlacing cancellation among contributions from the relevant KK levels. Such cancellations can be understood using a Kaluza–Klein equivalence theorem which results from the geometric “Higgs” mechanism of compactification. In these theories, the unitarity violation is delayed to energy scales higher than the customary limit through the introduction of additional vector bosons rather than Higgs scalars.
119177190
Probing LHC Higgs Signals from Extended Electroweak Gauge Group
We study the effects of the extended electroweak gauge sector on the signal strengths of the Higgs boson at the LHC. Extension of the Higgs sector associate with the extension of the electroweak gauge symmetry. In our setup, there are two neutral Higgs states ($h$, $H$) and three new gauge bosons ($W'^{\pm}$, $Z'$). We assume the lightest scalar, $h$, is what LHC found and its mass is 125 GeV. We find the enhancement of $\mu(gg \to h \to \gamma \gamma)$. On the other hand, other decay processes are same as or smaller than the SM expectation.
15162547
Quartic gauge boson couplings at linear colliders: Interplay of WWZ / ZZZ production and WW fusion
Abstract We study new physics effects to the quartic gauge boson couplings formulated by the electroweak chiral Lagrangian. Five next-to-leading order operators characterize the anomalous quartic gauge interactions which involve pure Goldstone boson dynamics for the electroweak symmetry breaking. We estimate the typical size of these couplings in different strongly-interacting models and examine the sensitivity to directly probing them via the WWZ / ZZZ triple gauge boson production at the high energy linear colliders. The important roles of polarized e − and e + beams are stressed. We then compare the results with those from the W -pair production of the WW -fusion processes, and analyze the interplay of these two production mechanisms for an improved probe of the quartic gauge boson interactions.