17 pages, 5 figures, 1 table. One high-energy control bin added to the fit, results of Table 1 updated accordingly, no change in the conclusions with the exception of model c5. Some references added and more details provided in the discussion. Updated to published version
The DAMA/LIBRA collaboration has recently released updated results from their search for the annual modulation signal expected from Dark Matter (DM) scattering in their NaI detectors. We have fitted the updated DAMA result for the modulation amplitudes in terms of a Weakly Interacting Massive Particle (WIMP) signal, parameterizing the interaction with nuclei in terms of the most general effective Lagrangian for a WIMP particle spin up to 1/2, systematically assuming dominance of one of the 14 possible interaction terms, and assuming for the WIMP velocity distribution a standard Maxwellian. We find that most of the couplings of the non-relativistic effective Hamiltonian can provide a better fit compared to the standard Spin Independent interaction case, and with a reduced fine-tuning of the three parameters (WIMP mass, WIMP-nucleon effective cross-section and ratio between the WIMP-neutron and the WIMP-proton couplings). Moreover, effective models for which the cross section depends explicitly on the WIMP incoming velocity can provide a better fit of the DAMA data at large values of $m_χ$ compared to the standard velocity-independent cross-section due to a different phase of the modulation amplitudes. All the best fit solutions are in tension with exclusion plots of both XENON1T and PICO60.
We analyze the DAMA/Libra-phase2 modulation result using a basis of 16 effective operators describing the WIMP interaction with photons, gluons and quarks up to mass dimension seven. For each operator we fix the effective theory at the scale of 2 GeV and parametrize WIMP-quark interactions in terms of two independent couplings for up-type and down-type quarks. We discuss the connection with the non-relativistic limit of the effective theory in terms of operators invariant by Galilean transformations, and the impact of the ensuing momentum-dependent Wilson coefficients due to long-range interac…
We show that the weakly interacting massive particle (WIMP) scenario of proton-philic spin-dependent inelastic dark matter can still provide a viable explanation of the observed DAMA effect in compliance with the constraints from other experiments. We also show that, although the COSINE-100 collaboration has recently tested the DAMA effect using the same target material, for the time being the comparison between DAMA and COSINE-100 still depends on the particle-physics model.
Guided by non-relativistic Effective Field Theory (EFT) we classify the most general spin-dependent interactions between a fermionic Weakly Interacting Massive Particle (WIMP) and nuclei, and within this class of models we discuss the viability of an interpretation of the DAMA modulation result in terms of a signal from WIMP elastic scatterings using a halo-independent approach. We find that, although several relativistic EFT's can lead to a spin-dependent cross section, in some cases with an explicit, non-negligible dependence on the WIMP incoming velocity, three main scenarios can be singled…
We present a halo-independent determination of the unmodulated signal corresponding to the DAMA modulation if interpreted as due to dark matter weakly interacting massive particles (WIMPs). First we show how a modulated signal gives information on the WIMP velocity distribution function in the Galactic rest frame, from which the unmodulated signal descends. Then we perform a mathematically-sound profile likelihood analysis in which we profile the likelihood over a continuum of nuisance parameters (namely, the WIMP velocity distribution). As a first application of the method, which is very gene…
We discuss a scenario where the DAMA modulation effect is explained by a Weakly Interacting Massive Particle (WIMP) which upscatters inelastically to a heavier state and predominantly couples to the spin of protons. In this scenario constraints from xenon and germanium targets are evaded dynamically, due to the suppression of the WIMP coupling to neutrons, while those from fluorine targets are evaded kinematically, because the minimal WIMP incoming speed required to trigger upscatters off fluorine exceeds the maximal WIMP velocity in the Galaxy, or is very close to it. In this scenario WIMP sc…
In the presence of OH impurities in the DAMA crystals, GeV-scale WIMPs elastically scattering off of hydrogen nuclei with a spin independent cross section of $\sim 10^{-33}\ {\rm cm}^2$ might explain the annual modulation observed by the DAMA experiment, while being consistent with other direct dark matter searches, as scattering would occur at energies below the energy threshold of other detectors. In this work we examine this possibility and show that, independent of the level of OH impurities in the DAMA crystals, for several reasons this scenario does not provide a viable explanation to th…
We show that the Weakly Interacting Massive Particle scenario of proton-philic spin-dependent inelastic Dark Matter (pSIDM) can still provide a viable explanation of the observed DAMA modulation amplitude in compliance with the constraints from other experiments after the release of the DAMA/LIBRA-phase2 data and including the recent bound from COSINE-100, that uses the same $NaI$ target of DAMA. The pSIDM scenario provided a viable explanation of DAMA/LIBRA--phase1 both for a Maxwellian WIMP velocity distribution and in a halo-independent approach. At variance with DAMA/LIBRA-phase1, for whic…
We investigate whether the annual modulation observed in the DAMA experiment can be due to a weakly-interacting massive particle (WIMP) with an axial-vector (spin-dependent; SD) coupling to nuclei. We evaluate the SD WIMP-proton cross section under the assumption that such scattering accounts for the DAMA modulation, and we do the same for a SD WIMP-neutron cross section. We show that SD WIMP-proton scattering is ruled out in a model-independent fashion by null searches for energetic neutrinos from WIMP annihilation in the Sun, and that SD WIMP-neutron scattering is ruled out for WIMP masses >…
In these proceedings, we report on the possible signatures of a light scalar WIMP, a dark matter candidate with M_DM ~ few GeV, which is supposed to interact with the Standard Model particles through the Higgs, and which might be related to the annual modulation observed by DAMA.
We reexamine the interpretation of the annual modulation signal observed by the DAMA experiment as due to WIMPs with a spin-dependent coupling mostly to protons. We consider both axial-vector and pseudo-scalar couplings, and elastic as well as endothermic and exothermic inelastic scattering. We conclude that the DAMA signal is in strong tension with null results of other direct detection experiments, particularly PICASSO and KIMS.
Since the DAMA/LIBRA collaboration released updated results from their search for the annual modulation signal expected from Dark Matter (DM) scattering in their NaI detectors, we have fitted the updated DAMA result for the modulation amplitudes for a Weakly Interacting Massive Particle (WIMP) signal, parameterizing the interaction with nuclei in terms of the most general effective Lagrangian for a WIMP particle spin 1/2, systematically assuming dominance of one of the 14 possible interaction terms and a standard Maxwellian for the WIMP velocity distribution. We find that most of the couplings…
The signals observed at the direct detection experiments DAMA, CoGeNT and CRESST could be explained by light WIMPs with sizeable spin-independent cross sections with nucleons. The capture and subsequent annihilation of such particles in the sun would induce neutrino signals in the GeV range which may be observed at Super-Kamiokande. We determine the rate of upward stopping muons and fully contained events at Super-Kamiokande for various possible WIMP annihilation channels. This allows us to provide strong constraints on the cross section of WIMPs with nucleons. We find that the DAMA and CoGeNT…
We examine whether the annual modulation found by the DAMA dark matter experiment can be explained by Weakly Interacting Massive Particles (WIMPs), in light of new null results from other experiments. CDMS II has already ruled out most WIMP-nucleus spin-independent couplings as an explanation for DAMA data. Hence we here focus on spin-dependent (axial vector; SD) couplings of WIMPs to nuclei. We expand upon previous work by (i) considering the general case of coupling to both protons and neutrons and (ii) incorporating bounds from all existing experiments. We note the surprising fact that CMDS…
Direct detection of Weakly Interacting Massive Particle (WIMP) candidates of Dark Matter (DM) is studied within the context of a self-consistent truncated isothermal model of the finite-size dark halo of the Galaxy based on the "King model" of the phase space distribution function of collisionless DM particles. Our halo model takes into account the modifications of the phase-space structure of the halo due to the gravitational influence of the observed visible matter in a self-consistent manner. The parameters of the halo model are determined by a fit to a recently determined circular rotation…
Recent results of the DAMA/NaI experiment for WIMP direct detection point to a possible annual modulation effect in the detection rate. We show that these results, when interpreted in terms of a relic neutralino, are compatible with supergravity models. Together with the universal SUGRA scheme, we also consider SUGRA models where the unification condition in the Higgs mass parameters at GUT scale is relaxed.
DAMA is searching for rare processes by developing and using several kinds of radiopure scintillators: in particular, NaI(Tl), liquid Xenon and CaF$_2$(Eu). The main results are here summarized with particular attention to the investigation of the WIMP annual modulation signature.
We investigate the possibility for the direct detection of low mass (GeV scale) WIMP dark matter in scintillation experiments. Such WIMPs are typically too light to leave appreciable nuclear recoils, but may be detected via their scattering off atomic electrons. In particular, the DAMA Collaboration [R. Bernabei et al., Nucl. Phys. At. Energy 19, 307 (2018)] has recently presented strong evidence of an annual modulation in the scintillation rate observed at energies as low as 1 keV. Despite a strong enhancement in the calculated event rate at low energies, we find that an interpretation in ter…
We discuss the interpretation of the annual modulation signal seen in the DAMA experiment in terms of spin-independent elastic WIMP scattering. Taking into account channeling in the crystal as well as the spectral signature of the modulation signal we find that the low-mass WIMP region consistent with DAMA data is confined to WIMP masses close to $m_χ\simeq 12$ GeV, in disagreement with the constraints from CDMS and XENON. We conclude that even if channeling is taken into account this interpretation of the DAMA modulation signal is disfavoured. There are no overlap regions in the parameter spa…
We study whether spin-independent scattering of weakly-interacting massive particles (WIMPs) with nuclei can account for the annual modulation signal reported by DAMA. We consider both elastic and inelastic scattering processes. We find that there is a region of WIMP parameter space which can simultaneously accommodate DAMA and the null results of CDMS, CRESST, and XENON. This region corresponds to an ordinary, elastically-scattering WIMP with a standard Maxwell-Boltzmann distribution, a mass 3 GeV < m_{DM} <8 GeV, and a spin-independent cross section with nucleons 3 \times 10^{-41} cm^2 < σ_p…
The DAMA experiment searches for Weakly Interacting Massive Particle (WIMP) dark matter via its expected but rare interactions within the detector, where the interaction rates will modulate throughout the year due to the orbital motion of the Earth. Over the course of more than 10 years of operation, DAMA has indeed detected a strong modulation in the event rate above the detector threshold of 2 keVee. Under standard assumptions regarding the dark matter halo and WIMP interactions, this signal is consistent with that expected of WIMPs of two different approximate masses: ~ 10 GeV and ~ 70 GeV.…
The DAMA/Libra experiment has recently confirmed the annual modulation signal obtained in the earlier DAMA/NaI experiment, providing strong evidence that they have actually detected dark matter. We examine the implications of this experiment for the mirror dark matter candidate. We show that mirror dark matter successfully explains the latest DAMA/Libra data, whilst also being consistent with the null results of other direct detection experiments.
A light scalar WIMP is studied in view of the recent results of the DAMA collaboration. In a scenario where both the WIMP's annihilation and its elastic scattering on nuclei occur dominantly through Higgs exchange, a one-to-one relation between the WIMP's relic density and its spin-independent direct detection rate is established. The ratio of the relevant cross sections depends only on the dark matter mass if the range allowed by the DAMA results (m < 10 GeV) is considered. We show that if such a light scalar WIMP possesses a direct detection rate compatible with DAMA, it naturally obtains a …
We discuss the compatibility of the combined annual modulation effect measured by DAMA/LIBRA-phase1 and DAMA/LIBRA-phase2 with an explanation in terms of inelastic scattering events induced by the most general Galilean-invariant effective contact interaction of a Weakly Interacting Massive Particle (WIMP) dark matter particle of spin 0, 1/2 or 1. We take into account all the possible interferences among operators by studying the intersections among the ellipsoidal surfaces of constant signal of DAMA and other experiments in the space of the coupling constants of the effective theory. In our an…
Assuming a standard Maxwellian for the WIMP velocity distribution, we obtain the bounds from null WIMP search results of 59.5 days of COSINE-100 data on the DAMA/LIBRA-phase2 modulation effect within the context of the non-relativistic effective theory of WIMP-nucleus scattering. Here, we systematically assume that one of the effective operators allowed by Galilean invariance dominates in the effective Hamiltonian of a spin-1/2 dark matter (DM) particle. We find that, although DAMA/LIBRA and COSINE-100 use the same sodium-iodide target, the comparison of the two results still depends on the pa…
We examine the effect of some uncertainties in the input astrophysical parameters on direct detection searches for WIMPs in the Galactic halo. We concentrate on the possible WIMP annual modulation signal recently reported by the DAMA Collaboration. We find that allowing for a reasonable uncertainty in a WIMP Maxwellian velocity distribution leads to significantly relaxed constraints on the WIMP mass as compared to the original DAMA analysis.
In the WIMP scenario, there is a one-to-one relation between the dark matter (DM) relic density and spin independent direct detection rate if both the annihilation of DM and its elastic scattering on nuclei go dominantly through Higgs exchange. In particular, for DM masses much smaller than the Higgs boson mass, the ratio of the relevant cross sections depends only on the DM mass. Assuming DM mass and direct detection rate within the ranges allowed by the recent DAMA collaboration results -taking account of the channelling effect on energy threshold and the null results of the other direct det…
We re-examine the case of anapole dark matter as an explanation for the DAMA annual modulation in light of the DAMA/LIBRA-phase2 results and improved upper limits from other DM searches. If the WIMP velocity distribution is assumed to be a Maxwellian, anapole dark matter is unable to provide an explanation of the DAMA modulation compatible with the other searches. Nevertheless, anapole dark matter provides a better fit to the DAMA-phase2 modulation data than an isoscalar spin-independent interaction, due to its magnetic coupling with sodium targets. A halo-independent analysis shows that expla…
Upper limits on the spin-independent (SI) as well as spin-dependent (SD) elastic scattering cross sections of WIMPs with protons, imposed by the Super-Kamiokande (S-K) upper limit on the neutrino flux from WIMP annihilation in the Sun, and their compatibility with the "DAMA-compatible" regions of the WIMP parameter space within which the annual modulation signal observed by the DAMA/LIBRA experiment is compatible with the null results of other direct detection experiments, are studied within the frame work of a self-consistent model of the finite-size dark matter (DM) halo of the Galaxy, the p…
In these proceedings, I report on the status of a simple singlet scalar dark matter model in the light of recent results from both direct detection experiments, in particular DAMA, CoGeNT, CDMS-II and Xenon10/100, and indirect searches, in particular Fermi-LAT. Specifically, I confront the light scalar WIMP candidates, M_DM ~ few GeV, that are consistent with CoGeNT and/or DAMA, to constraints that may be set using the recent Fermi-LAT data on Milky Way dwarf spheroidal galaxies (dSphs) and the isotropic diffuse gamma-ray emission. I show that the latter observations set relevant exclusion lim…
A weakly interacting massive particle (WIMP) weighing only a few GeV has been invoked as an explanation for the signal from the DAMA/LIBRA experiment. We show that the data from DAMA/LIBRA are now powerful enough to strongly constrain the properties of any putative WIMP. Accounting for the detailed recoil spectrum, a light WIMP with a Maxwellian velocity distribution and a spin-independent (SI) interaction cannot account for the data. Even neglecting the spectrum, much of the parameter space is excluded by limits from the DAMA unmodulated signal at low energies. Significant modifications to th…
The present DAMA/LIBRA experiment and the former DAMA/NaI have cumulatively released so far the results obtained with the data collected over 13 annual cycles (total exposure: 1.17 ton $\times$ yr). They give a model independent evidence of the presence of DM particles in the galactic halo on the basis of the DM annual modulation signature at 8.9 $σ$ C.L. for the cumulative exposure.
In this paper, we study the recent excess of low energy events observed by the CoGeNT collaboration, and discuss the possibility that these events originate from the elastic scattering of a light (m_DM ~ 5-10 GeV) dark matter particle. We find that such a dark matter candidate may also be capable of generating the annual modulation reported by DAMA, as well as the small excess recently reported by CDMS, without conflicting with the null results from other experiments, such as XENON10. A dark matter interpretation of the CoGeNT and DAMA observations favors a region of parameter space that is es…
Recently, the DAMA/LIBRA collaboration has repeated and reinforced their claim to have detected an annual modulation in their signal rate, and have interpreted this observation as evidence for dark-matter particles at the 8.2 sigma confidence level. Furthermore, it has also been noted that the effects of channeling may enable a WIMP that scatters elastically via spin-independent interactions from nuclei to produce the signal observed by DAMA/LIBRA without exceeding the limits placed by CDMS, XENON, CRESST, CoGeNT and other direct-detection experiments. To accommodate this signal, however, the …
We analyze the properties of neutralino under the hypothesis that some preliminary experimental results of the DAMA/NaI Collaboration may be indicative of a yearly modulation effect. We examine which supersymmetric configurations would be singled out by the DAMA/NaI data. We also discuss the possibility to investigate these configurations by means of experimental searches for relic neutralinos other than direct searches. We finally discuss the possibility to probe these configurations by accelerator searches.
The annual modulation in the rate of WIMP recoils observed by the DAMA collaboration at high significance is often analyzed in the context of an isothermal Maxwell-Boltzmann velocity distribution. While this is the simplest model, there is a need to consider other well motivated theories of halo formation. In this paper, we study a different halo model, that of self similar infall which is characterized by the presence of a number of cold streams and caustics, not seen in simulations. It is shown that the self similar infall model is consistent with the DAMA result both in amplitude and in pha…
We compute the primordial mirror helium He' mass fraction emerging from Big Bang nucleosynthesis in the mirror sector of particles in the presence of kinetic mixing between photons and mirror photons. We explore the kinetic mixing parameter (epsilon) values relevant for cosmology and which are also currently probed by the dark matter direct detection experiments. In particular, we find that for epsilon \sim 10^{-9}, as suggested by the DAMA/Libra and other experiments, a large He' mass fraction (Y_{He'} \approx 90%) is produced. Such a large value of the primordial He' mass fraction will have …
The DAMA/NaI Collaboration has observed a 4-sigma C.L. model independent effect investigating the annual modulation signature in the counting rate of an NaI(Tl) set-up (total exposure of 57986 kg day) and the implications of this effect have been studied under different model-dependent assumptions. In this paper we extend one of the previous analyses, the case of a WIMP with a purely spin-independent coupling, by discussing in detail the implications on the results of the uncertainties on the dark matter galactic velocity distribution. We study in a systematic way possible departures from the …
The Weakly Interacting Massive Particle (WIMP) is one of the main candidates for the relic dark matter (DM).In the effective low-energy minimal supersymmetric standard model (effMSSM) the neutralino-nucleon spin and scalar cross sections in the low-mass regime were calculated. The calculated cross sections are compared with almost all experimental currently available exclusion curves for spin-dependent WIMP-proton and WIMP-neutron cross sections. It is demonstrated that in general about two-orders-of-magnitude improvement of the current DM experiment sensitivities is needed to reach the (effMS…
Using the DAMA/LIBRA anomaly as an example, we formalise the notion of halo-independence in the context of Bayesian statistics and quantified maximum entropy. We consider an infinite set of possible profiles, weighted by an entropic prior and constrained by a likelihood describing noisy measurements of modulated moments by DAMA/LIBRA. Assuming an isotropic dark matter (DM) profile in the galactic rest frame, we find the most plausible DM profiles and predictions for unmodulated signal rates at DAMA/LIBRA. The entropic prior contains an a priori unknown regularisation factor, $β$, that describe…
The current paradigm for dark matter direct detection is to assume that the dark sector is solely composed of a single particle species. In this short paper, we make the observation that dark matter comprising both a light and a heavy component that modulate out of phase leads to interesting phenomenology in annual modulation experiments. For an illustrative example, we use the recently released DAMA/LIBRA phase-2 results with a lower energy threshold. Immediately after, it was argued that a one-component spin-independent dark matter explanation of the observed annual modulation is strongly di…
The GENIUS proposal is described and some of it's physics potential is outlined. Also in the light of the contradictive results from the DAMA and CDMS experiments the Genius TF, a new experimental setup is proposed. The Genius TF could probe the DAMA evidence region using the WIMP nucleus recoil signal and WIMP annual modulation signature simultaneously. Besides that it can prove the long term feasibility of the detector technique to be implemented into the GENIUS setup and will in this sense be a first step towards the realization of the GENIUS experiment.
An analysis is given of the annual modulation signal for the direct detection of relic neutralinos within the framework of supergravity unified models. It is shown that both the minimal and the non-minimal SUGRA models can generate neutralino-proton cross-sections at the level compatible with the signals reported in the DAMA experiment at the Gran Sasso National Laboratory. Effects of proton stability on the analysis of the DAMA data in the minimal and the non-minimal SUGRA models are also discussed.
Models of dark matter with ~ GeV scale force mediators provide attractive explanations of many high energy anomalies, including PAMELA, ATIC, and the WMAP haze. At the same time, by exploiting the ~ MeV scale excited states that are automatically present in such theories, these models naturally explain the DAMA/LIBRA and INTEGRAL signals through the inelastic dark matter (iDM) and exciting dark matter (XDM) scenarios, respectively. Interestingly, with only weak kinetic mixing to hypercharge to mediate decays, the lifetime of excited states with delta < 2 m_e is longer than the age of the unive…
Many experiments seek dark matter by detecting relatively low energy nuclear recoils. Yet since events from ordinary physics with energies in the 1-100 KeV range are commonplace, all claims of signals or their absence hinge on exhaustive calibrations and background rejection. We document many curious and consistent discrepancies between the backgrounds which neutrons can produce versus the picture of neutrons and claims of neutron calibration found in dark matter literature. Much of the actual physics of neutrons is either under-recognized or under-reported, opening up new interpretations of c…
The DAMA/NaI and DAMA/LIBRA annual modulation data, which may be interpreted as a signal for the existence of weakly interacting dark matter (WIMPs) in our galactic halo, are examined in light of null results from other experiments. We use the energy spectrum of the combined DAMA modulation data given in 36 bins, and include the effect of channeling. Several statistical tools are implemented in our study: likelihood ratio with a global fit and with raster scans in the WIMP mass and goodness-of-fit (g.o.f.). These approaches allow us to differentiate between the preferred (global best fit) and …
We argue that current neutron star observations exclude asymmetric bosonic non-interacting dark matter in the range from 2 keV to 16 GeV, including the 5-15 GeV range favored by DAMA and CoGeNT. If bosonic WIMPs are composite of fermions, the same limits apply provided the compositeness scale is higher than ~10^12 GeV (for WIMP mass ~1 GeV). In case of repulsive self-interactions, we exclude large range of WIMP masses and interaction cross sections which complements the constraints imposed by observations of the Bullet Cluster.
There is a long standing debate about whether or not the annual modulation signal reported by the DAMA/LIBRA collaboration is induced by Weakly Interacting Massive Particles~(WIMP) in the galaxy's dark matter halo scattering from nuclides in their NaI(Tl) crystal target/detector. This is because regions of WIMP-mass vs. WIMP-nucleon cross-section parameter space that can accommodate the DAMA/LIBRA-phase1 modulation signal in the context of the standard WIMP dark matter galactic halo and isospin-conserving~(canonical), spin-independent~(SI) WIMP-nucleon interactions have been excluded by many o…
We consider the compatibility of DAMA/LIBRA, CoGeNT, XENON10 and XENON100 results for spin-independent (SI) dark matter Weakly Interacting Massive Particles (WIMPs), particularly at low masses (~ 10 GeV), assuming a standard dark matter halo. The XENON bounds depend on the scintillation efficiency factor Leff for which there is considerable uncertainty. Thus we consider various extrapolations for Leff at low energy. With the Leff measurements we consider, XENON100 results are found to be insensitive to the low energy extrapolation. We find the strongest bounds are from XENON10, rather than XEN…
We consider the hypothesis that Dark Matter (DM) has tree-level interactions only with leptons. Such a framework, where DM recoils against electrons bound in atoms, has been proposed as an explanation for the annually modulated scintillation signal in DAMA/LIBRA versus the absence of a signal for nuclear recoils in experiments like CDMS or XENON10. However, even in such a leptophilic DM scenario there are loop induced DM-hadron interactions, where the photons emitted from virtual leptons couple to the charge of a nucleus. Using a general effective field theory approach we show that, if such an…
Recently, the DAMA/LIBRA collaboration released updated results from their search for the annual modulation signal from Dark Matter (DM) scattering in the detector. Besides approximately doubling the exposure of the DAMA/LIBRA data set, the updated photomultiplier tubes of the experiment allow a lower recoil energy threshold of 1\,keV electron equivalent compared to the previous threshold of 2 keV electron equivalent. We study the compatibility of the observed modulation signal with DM scattering. Due to a conspiracy of multiple effects, the new data at low recoil energies is very powerful for…
We investigate the interactions of Weakly Interacting Massive Particles (WIMPs) with nuclei in the human body. We are motivated by the fact that WIMPs are excellent candidates for the dark matter in the Universe. Our estimates use a 70 kg human and a variety of WIMP masses and cross-sections. The contributions from individual elements in the body are presented and it is found that the dominant contribution is from scattering off of oxygen (hydrogen) nuclei for the spin-independent (spin-dependent) interactions. For the case of 60 GeV WIMPs, we find that, of the billions of WIMPs passing throug…
In this note we present an extension of our previous analysis of some preliminary experimental results of the DAMA/NaI Collaboration which might be indicative of a yearly modulation effect. Here we present a direct way for obtaining from the experimental data the relevant cosmological implications for relic neutralinos. We find that some of the configurations singled out by the DAMA/NaI results would have cosmological properties compatible with a neutralino as a dominant component of cold dark matter (on the average in the Universe and in our galactic halo).
We consider the prospects for probing low-mass dark matter with the Super-Kamiokande experiment. We show that upcoming analyses including fully-contained events with sensitivity to dark matter masses from 5 to 10 GeV can test the dark matter interpretation of the DAMA/LIBRA signal. We consider prospects of this analysis for two light dark matter candidates: neutralinos and WIMPless dark matter.
Measurements from the Gaia satellite have greatly increased our knowledge of the dark matter velocity distributions in the Solar neighborhood. There is evidence for multiple cold structures nearby, including a high-velocity stream counterrotating relative to the Sun. This stream could significantly alter the spectrum of recoil energies and increase the annual modulation of dark matter in direct detection experiments such as DAMA/Libra. We reanalyze the experimental limits from Xenon1T, CDMSlite, PICO-60 and COSINE-100, and compare them to the results of the DAMA/Libra experiment. While we find…
The long-standing model-independent annual modulation effect measured by DAMA deep underground at Gran Sasso Laboratory with different experimental configurations is summarized and perspectives will be highlighted. DAMA/LIBRA-phase2 set-up, $\simeq$ 250 kg highly radio-pure NaI(Tl) confirms the evidence of a signal that meets all the requirements of the model independent Dark Matter annual modulation signature at high C.L.; the full exposure is 2.86 ton $\times$ yr over 22 annual cycles. The experiment is currently collecting data in the DAMA/LIBRA-phase2 empowered configuration with an even l…
We study the details of the DAMA/LIBRA results and compare those with the recent published DM Ice results of ICE Cube. In various recent papers, it was shown that the 40K peak on DAMA/LIBRA data leaves no room for a Dark Matter signal in the bulk of the data. Using Information Theory for the different types of detection environments, we show that annual variation calculations and the DM Ice data reinforce the claims that the DAMA/LIBRA detector is not observing Dark Matter WIMPs.
In this paper, we study the recent excess of low energy events observed by the CoGeNT collaboration and the annual modulation reported by the DAMA/LIBRA collaboration, and discuss whether these signals could both be the result of the same elastically scattering dark matter particle. We find that, without channeling but when taking into account uncertainties in the relevant quenching factors, a dark matter candidate with a mass of approximately ~7.0 GeV and a cross section with nucleons of sigma_{DM-N} ~2x10^-4 pb (2x10^-40 cm^2) could account for both of these observations. We also comment on …
Several of the many proposed Dark Matter candidate particles, already investigated with lower exposure and a higher software energy threshold, are further analyzed including the first DAMA/LIBRA--phase2 data release, with an exposure of 1.13 ton $\times$ yr and a lower software energy threshold (1 keV). The cumulative exposure above 2 keV considering also DAMA/NaI and DAMA/LIBRA--phase1 results is now 2.46 ton $\times$ yr. The analysis permits to constraint the parameters' space of the considered candidates restricting their values -- with respect to previous analyses -- thanks to the increase…
We consider the prospects for testing the dark matter interpretation of the DAMA/LIBRA signal with the Super-Kamiokande experiment. The DAMA/LIBRA signal favors dark matter with low mass and high scattering cross section. We show that these characteristics imply that the scattering cross section that enters the DAMA/LIBRA event rate determines the annihilation rate probed by Super-Kamiokande. Current limits from Super-Kamiokande through-going events do not test the DAMA/LIBRA favored region. We show, however, that upcoming analyses including fully-contained events with sensitivity to dark matt…
Inelastic dark matter, in which WIMP-nucleus scatterings occur through a transition to an excited WIMP state ~ 100 keV above the ground state, provides a compelling explanation of the DAMA annual modulation signal. We demonstrate that the relative sensitivities of various dark matter direct detection experiments are modified such that the DAMA annual modulation signal can be reconciled with the absence of a reported signal at CDMS-Soudan, XENON10, ZEPLIN, CRESST, and KIMS for inelastic WIMPs with masses O(100 GeV). We review the status of these experiments, and make predictions for upcoming on…
