The inert doublet model (IDM), a two Higgs extension of the standard with an unbroken Z 2 symmetry, is simple and yet rich dark matter. We present systematic analysis matter abundance investigate potentialities for direct gamma indirect detection. show that should be within range future experiments, like GLAST ZEPLIN. lightest stable scalar in IDM perfect example, or archetype weakly interacting massive particle.

We consider the possibility that along thermal history of Universe, dark matter (DM) would have been created from Standard Model particles, either through a kinetic mixing portal to an extra U(1) gauge field, or Higgs portal. Depending solely on DM particle mass, and hidden sector interaction, we show how observed relic density can be obtained. There are four possible freeze-in/reannihilation/freeze-out regimes, which together result in simple characteristic phase diagram, with shape...

The mechanism behind Electroweak Symmetry Breaking (EWSB) and the nature of dark matter (DM) are currently among most important issues in high energy physics. Since a natural candidate is weakly interacting massive particle or WIMP, with mass around electroweak scale, it clearly interest to investigate possibility that DM EWSB closely related. In context very simple extension Standard Model, Inert Doublet we show could play crucial role breaking symmetry. this model, lightest component an...

In the WIMP scenario, there is a one-to-one relation between dark matter (DM) relic density and spin-independent direct detection rate if both annihilation of DM its elastic scattering on nuclei go dominantly through Higgs exchange. particular, for masses much smaller than boson mass, ratio relevant cross sections depends only mass. Assuming mass within ranges allowed by recent DAMA collaboration results—taking account channelling effect energy threshold null results other experiments—gives...

If dark matter (DM) simply consists in a scalar particle interacting dominantly with the Higgs boson, ratio of its annihilation cross section ---which is relevant both for relic abundance and indirect detection--- spin-independent scattering on nuclei depends only DM mass. It an intriguing result that, fixing mass direct detection rate to fit annual modulation observed by DAMA experiment, one obtains density perfect agreement value. In this short letter we update confront model recent CoGeNT...

Abstract We study a scenario in which the expansion of Early Universe is driven by hot hidden sector (HS) with an initial temperature T ' that significantly higher than visible (VS), ≫ . The latter assumed to be made Standard Model (SM) particles and our main focus on possibility dark matter (DM) part dominant HS its abundance set secluded freeze-out. In particular, we subsequent evolution fate DM companion particle after freeze-out all way toward reheating VS. To make this more concrete,...

We investigate the signatures of neutrinos produced in annihilation WIMP dark matter Earth, Sun and at Galactic centre within framework Inert Doublet Model extensions. consider a candidate, that we take to be one neutral components an extra Higgs doublet, three distinct mass ranges, which have all been shown previously consistent with both WMAP abundance direct detection experiments exclusion limits. Specifically, light between 4 8 GeV (low), around 60-70 (middle) heavy above 500 (high). In...

In the framework of Inert Doublet Model, a very simple extension Standard we study production and propagation antimatter in cosmic rays coming from annihilation scalar dark matter particle. We consider three benchmark candidates, all consistent with WMAP abundance existing direct detection experiments, confront predictions model recent PAMELA, ATIC HESS data. For light candidate, MDM ∼ 10 GeV, argue that positron anti-proton fluxes may be large, but still expected backgrounds, unless there...

In dark matter (DM) models, the production of a gamma line (or "box-shaped" gamma-ray spectrum) from DM annihilation proceeds in general loop diagram involving heavy charged particle. If particle carries also color charge, this leads inevitably to gluons, with naturally larger rate. We consider scenario which candidates annihilate dominantly into gluon pairs, and determine (as far as possible, model-independent) constraints variety observables: a) relic density, b) anti-protons, c) direct...

Dark matter (DM) may belong to a hidden sector (HS) that is only feebly interacting with the standard model (SM) and have never been in thermal equilibrium early Universe. In this case, observed abundance of dark particles could built up through process known as freeze-in. We show that, for first time, direct detection experiments are testing DM production mechanism. This applies scenarios where SM HS communicate light mediator mass less than few MeV. Through exchange such mediator, very...

We propose a mechanism that can convert sizeable fraction of neutron stars into black holes with mass $\sim 1M_\odot$, too light to be produced via standard stellar evolution. show asymmetric fermionic dark matter $\sim$ TeV, attractive self-interaction within the range alleviates problems collisionless cold matter, accumulate in star and collapse, forming seed hole converts rest solar hole. estimate become without contradicting existing observations. Like stars, such could binary systems,...

We analyze how dark matter (DM) can be produced in the early Universe, working framework of a hidden sector charged under $U(1{)}^{\ensuremath{'}}$ gauge symmetry and interacting with Standard Model through kinetic mixing. Depending on masses particle photon, as well coupling mixing parameter, we classify all distinct regimes along which observed relic density accounted for. find that nine are potentially operative to produce DM particles, these operate five dynamical mechanisms. Among...

A bstract Future dark matter (DM) direct detection searches will be subject to irreducible neutrino backgrounds that challenge the identification of an actual WIMP signal in experiments without directionality sensitivity. We study impact neutrino-quark non-standard interactions (NSI) on this background, assuming constraints from oscillations and recent COHERENT experiment data, which are relevant for NSI mediated by light mediators, $$ {m}_{\mathrm{med}}\lesssim...

The annual modulation observed by DAMA/NaI and DAMA/Libra may be interpreted in terms of elastic or inelastic scattering dark matter particles. In this paper we confront these two scenarios within the framework a very simple extension Standard Model, Inert Doublet Model (IDM). model candidate is scalar, lightest component an extra Higgs doublet. We first revisit case for light scalar WIMP, MDM ∼ 10 GeV, scenario which requires that fraction events DAMA are channelled. Second consider...

There has been interest recently on particle physics models that may give rise to sharp gamma ray spectral features from dark matter annihilation. Because is supposed be electrically neutral, it challenging build weakly interacting massive accommodate both a large cross section into rays at, say, the Galactic center, and right abundance. In this work, we consider signatures of class scalar interact with Standard Model dominantly through heavy vector-like fermions (the portal). We focus real...

We consider the annihilation into gamma rays of Minimal Dark Matter candidates in fermionic 5-plet and scalar 7-plet representations $SU(2)_L$, taking account both Sommerfeld effect internal bremsstrahlung. Assuming Einasto profile, we show that present measurements Galactic Center by H.E.S.S. instrument exclude as dominant form dark matter for masses between 1 TeV 20 TeV, particular, mass leading to observed density via thermal freeze-out. also discuss prospects upcoming Cherenkov Telescope...

We investigate the phenomenology of scalar singlet dark matter candidates that couple dominantly to Standard Model via a Yukawa interaction with top quark and colored vector-like fermion. estimate viability this portal scenario respect most recent bounds from direct indirect detection, as well mediator searches at colliders. Moreover, we take QCD radiative corrections into account in all our theoretical calculations. This work complements analyses related both models featuring coupled...

The existence of Dark Matter (DM) in the form Strongly Interacting Massive Particles (SIMPs) may be motivated by astrophysical observations that challenge classical Cold DM scenario. Other greatly constrain, but do not completely exclude, SIMP alternative. signature SIMPs at LHC consist neutral, hadron-like, trackless jets produced pairs. We show absence charged content can provide a very efficient tool to suppress dijet backgrounds LHC, thus enhancing sensitivity potential signal....

We embed a thermal dark matter (DM) candidate within the clockwork framework. This mechanism allows to stabilize DM particle over cosmological time because it suppresses its decay into Standard Model (SM) particles. At same time, pair annihilations are unsuppressed, so that relic density is set by usual freeze-out of from bath. The slow induced "clockwork" particles can be quite light (rather than at some GUT or Planck scale) and could searched for current future colliders. According...

The fraction of primordial black holes (PBHs) masses ${10}^{17}--{10}^{26}\text{ }\text{ }\mathrm{g}$ in the total amount dark matter may be constrained by considering their capture neutron stars (NSs), which leads to rapid destruction latter. constraints depend crucially on rate which, turn, is determined energy loss a PBH passing through NS. Two alternative approaches estimate have been used literature: one based dynamical friction mechanism, and another tidal deformations NS PBH. second...

Motivated by the measurements reported direct detection experiments, most notably DAMA, CDMS-II, CoGeNT and Xenon10/100, we study further constraints that might be set on some light dark matter candidates, MDM ∼ few GeV, using Fermi-LAT data isotropic gamma-ray diffuse emission. In particular, consider a Dirac fermion singlet interacting through new Z' gauge boson, scalar S Higgs portal. Both candidates are WIMP (Weakly Interacting Massive Particles), i.e. they have an annihilation...

The grand-unification gauge group SO(10) contains matter parity as a discrete subgroup. This symmetry could be at the origin of dark stability. properties candidates depend on path along which is broken, in particular through Pati-Salam or left-right symmetric subgroups. We systematically determine non-supersymmetric scenarios that can realized various paths. emphasize may have colored electrically charged partners low scale belong to same multiplet. These states, many cases are important...