Using the latest AMS-02 cosmic ray antiproton flux data, we search for potential dark matter annihilation signal. The background parameters about the propagation, source injection, and solar modulation are not assumed a priori, but based on the results inferred from the recent B/C ratio and proton data measurements instead. The possible dark matter signal is incorporated into the model self-consistently under a Bayesian framework. Compared with the astrophysical background only hypothesis, we find that a dark matter signal is favored. The rest mass of the dark matter particles is ∼ 20 − 80 GeV and the velocity-averaged hadronic annihilation cross section is about (0.2 − 5) × 10 −26 cm 3 s −1 , in agreement with that needed to account for the Galactic center GeV excess and/or the weak GeV emission from dwarf spheroidal galaxies Reticulum 2 and Tucana III. Tight constraints on the dark matter annihilation models are also set in a wide mass region. PACS numbers: 95.35.+d,Introduction -The precise measurements of cosmic ray (CR) anti-particle spectra by space-borne instruments, such as PAMELA and AMS-02, provide very good sensitivity to probe the particle dark matter (DM) annihilation or decay in the Milky Way. The CR antiprotons, primarily come from the inelastic collisions between the CR protons (and Helium) and the interstellar medium (ISM), are effective to constrain the DM models [1][2][3]. Recent observations of the antiproton fluxes [4][5][6] are largely consistent with the expectation from the CR propagation model, leaving very limited room for the annihilation or decay of DM [2,[7][8][9][10].There are several sources of uncertainties in using antiprotons to constrain DM models. The largest uncertainty may come from the propagation parameters. Usually the secondary-to-primary ratio of CR nuclei, such as the Boronto-Carbon ratio (B/C), and the radioactive-to-stable isotope ratio of secondary nuclei, such as the Beryllium isotope ratio 10 Be/ 9 Be, are used to determine the propagation parameters [11,12]. Limited by the data quality, the constraints on the propagation parameters are loose [13,14]. Even the effect on the background antiproton flux due to uncertainties of propagation parameters is moderate, the flux from the DM component depends sensitively on propagation parameters [15]. Additional uncertainties include the injection spectrum of the CR nuclei, solar modulation, and hadronic interaction models [8]. Those uncertainties make the DM searches with antiprotons inconclusive [16,17].Given the new measurements of the proton, Helium, and B/C data by , improved constraints on the propagation and source injection parameters can be obtained through global Bayesian approaches [22][23][24][25]. With these data, we conduct a global study to determine the propagation, injection, and solar modulation parameters si- * The corresponding author: yuanq@pmo.ac.cn † The corresponding author: yzfan@pmo.ac.cn multaneously using the Markov Chain Monte Carlo (MCMC) method [26]. These "background" parameters and their like...
In light of the recent discovery by the ATLAS and CMS experiments at the Large Hadron Collider (LHC) of a Higgs-like particle with a narrow mass range of 125–126 GeV, we perform an updated analysis on one of the popular scalar dark matter models, the Inert Higgs Doublet Model (IHDM). We take into account in our likelihood analysis of various experimental constraints, including recent relic density measurement, dark matter direct and indirect detection constraints as well as the latest collider constraints on the invisible decay width of the Higgs boson and monojet search at the LHC. It is shown that if the invisible decay of the standard model Higgs boson is open, LHC as well as direct detection experiments like LUX and XENON100 could put stringent limits on the Higgs boson couplings to dark matter. We find that the most favoured parameter space for IHDM corresponds to dark matter with a mass less than 100 GeV or so. In particular, the best-fit points are at the dark matter mass around 70 GeV where the invisible Higgs decay to dark matter is closed. Scalar dark matter in the higher mass range of 0.5–4 TeV is also explored in our study. Projected sensitivities for the future experiments of monojet at LHC-14, XENON1T and AMS-02 one year antiproton flux are shown to put further constraints on the existing parameter space of IHDM.
We present an updated and extended global analysis of the Constrained MSSM (CMSSM) taking into account new limits on supersymmetry from ∼ 5/fb data sets at the LHC. In particular, in the case of the razor limit obtained by the CMS Collaboration we simulate detector efficiency for the experimental analysis and derive an approximate but accurate likelihood function. We discuss the impact on the global fit of a possible Higgs boson with mass near 125 GeV, as implied by recent data, and of a new improved limit on BR Bs → µ + µ − . We identify high posterior probability regions of the CMSSM parameters as the stau-coannihilation and the A-funnel region, with the importance of the latter now being much larger due to the combined effect of the above three LHC results and of dark matter relic density. We also find that the focus point region is now disfavored. Ensuing implications for superpartner masses favor even larger values than before, and even lower ranges for dark matter spin-independent cross section, σ SI p ∼ < 10 −9 pb. We also find that relatively minor variations in applying experimental constraints can induce a large shift in the location of the best-fit point. This puts into question the robustness of applying the usual χ 2 approach to the CMSSM. We discuss the goodness-of-fit and find that, while it is difficult to calculate a p-value, the (g − 2)µ constraint makes, nevertheless, the overall fit of the CMSSM poor. We consider a scan without this constraint, and we allow µ to be either positive or negative. We find that the global fit improves enormously for both signs of µ, with a slight preference for µ < 0 caused by a better fit to BR (b → sγ) and BR Bs → µ + µ − .
We explore the MSSM with 9 free parameters (p9MSSM) that have been selected as a minimum set that allows an investigation of neutralino dark matter and collider signatures while maintaining consistency with several constraints. These include measurement of the dark matter relic density from PLANCK, main properties of the discovered Higgs boson, LHC direct SUSY searches, recent evidence for a Standard Model-like BR (B s → µ + µ − ), and the measurement of δ (g − 2) µ , plus a number of other electroweak and flavor physics constraints. We perform a simulation of two LHC direct SUSY searches at √ s = 8 TeV: the CMS inclusive α T search for squarks and gluinos and the CMS electroweak production search with 3l+E miss T in the final state. We use the latter to identify the regions of the parameter space, consistent at 2σ with δ (g − 2) µ , that are not excluded by the direct limits from the electroweak production. We find that they correspond to a neutralino mass in the window 200 GeV m χ 500 GeV. We also implement the likelihood for the XENON100 exclusion bound, in which we consider for the first time the impact of a recent determination of the Σ πN term from CHAOS data, Σ πN = 43 ± 12 MeV. We show that in light of this measurement, the present statistical impact of the XENON100 bound is greatly reduced, although future sensitivities of the LUX and XENON1T experiments will have decisive impact on the mixed bino/higgsino composition of the neutralino. We point out some tension between the constraints from δ (g − 2) µ and XENON100. Finally, we present prospects for various indirect searches of dark matter, namely γ-ray fluxes from dSphs and the Galactic Center at Fermi-LAT, and the positron flux at AMS02. We also show the 5-year sensitivity on the spin-dependent neutralino-proton cross section due to neutrino fluxes from the Sun at IceCube. * On leave of absence from the University of Sheffield, U.K.
An effective interaction approach is used to describe the interactions between the spin 0 or spin 1/2 dark matter particle and the degrees of freedom of the standard model. This approach is applicable to those models in which the dark matter particles do not experience the standardmodel interactions, e.g., hidden-sector models. We explore the effects of these effective interaction operators on (i) dark matter relic density, (ii) spin-independent and spin-dependent dark matternucleon scattering cross sections, (iii) cosmic antiproton and gamma ray fluxes from the galactic halo due to dark matter annihilation, and (iv) monojet and monophoton production plus missing energy at the Tevatron and the Large Hadron Collider (LHC). We combine the experimental data of relic density from WMAP7, spin-independent cross section from XENON100, spin-dependent cross section from XENON10, ZEPLIN-III, and SIMPLE, cosmic antiproton flux from PAMELA, cosmic gamma-ray flux from Fermi -LAT, and the monojet and monophoton data from the Tevatron and the LHC, to put the most comprehensive limits on each effective operator.
The lepton-sepcific (or type X) 2HDM (L2HDM) is an attractive new physics candidate explaining the muon g − 2 anomaly requiring a light CP-odd boson A and large tan β. This scenario leads to τ -rich signatures, such as 3τ , 4τ and 4τ + W/Z, which can be readily accessible at the LHC. We first study the whole L2HDM parameter space to identify allowed regions of extra Higgs boson masses as well as two couplings λ hAA and ξ l h which determine the 125 GeV Higgs boson decays h → τ + τ − and h → AA/AA * (τ + τ − ), respectively. This motivates us to set up two regions of interest: (A) m A m H ∼ m H ± , and (B) m A ∼ m H ± ∼ O(100)GeV m H , for which derive the current constraints by adopting the chargino-neutralino search at the LHC8, and then analyze the LHC14 prospects by implementing τ -tagging algorithm. A correlated study of the upcoming precision determination of the 125 GeV Higgs boson decay properties as well as the observation of multi-tau events at the next runs of LHC will be able to shed light on the L2HDM option for the muon g − 2.
The complex scalar dark matter (DM) candidate in the gauged two-Higgs-doublet model, stabilized by a peculiar hidden parity (h parity), is studied in detail. We explore the parameter space for the DM candidate by taking into account the most recent DM constraints from various experiments, in particular, the PLANCK relic density measurement and the current DM direct detection limit from XENON1T. We separate our analysis in three possible compositions for the mixing of the complex scalar. We first constrain our parameter space with the vacuum stability and perturbative unitarity conditions for the scalar potential, LHC Higgs measurements, plus Drell-Yan and electroweak precision test constraints on the gauge sector. We find that DM dominated by composition of the inert doublet scalar is completely excluded by further combining the previous constraints with both the latest results from PLANCK and XENON1T. We also demonstrate that the remaining parameter space with two other DM compositions can be further tested by indirect detection like the future Cherenkov Telescope Array gamma-ray telescope.
Serious searches for the weakly interacting massive particle (WIMP) have now begun. In this context, the most important questions that need to be addressed are: To what extent can we constrain the WIMP models in the future? and What will then be the remaining unexplored regions in the WIMP parameter space for each of these models? In our quest to answer these questions, we classify WIMP in terms of quantum number and study each case adopting minimality as a guiding principle. As a first step, we study one of the simple cases of the minimal composition in the well-tempered fermionic WIMP regime, namely the singlet-doublets WIMP model. We consider all available constraints from direct and indirect searches and also the predicted constraints coming from the near future and the future experiments. We thus obtain the current status, the near future prospects and the future prospects of this model in all its generality. We find that in the future, this model will be constrained almost solely by the future direct dark matter detection experiments (as compared to the weaker indirect and collider constraints) and the cosmological (relic density) constraints and will hence be gradually pushed to the corner of the coannihilation region, if no WIMP signal is detected. Future lepton colliders will then be useful in exploring this region not constrained by any other experiments.
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