5141632
Ordinary atom mirror atom bound states: A New window on the mirror world
Mirror symmetry is a plausible candidate for a fundamental symmetry of particle interactions which can be exactly conserved if a set of mirror particles exist. The properties of the mirror particles seem to provide an excellent candidate to explain the inferred dark matter of the Universe and might also be responsible for a variety of other puzzles in particle physics, astrophysics, meteoritics and planetary science. One such puzzle\char22{}the orthopositronium lifetime problem\char22{}can be explained if there is a small kinetic mixing of ordinary and mirror photons. We show that this kinetic mixing implies the existence of ordinary atom\char21{}mirror-atom bound states with interesting terrestrial and astrophysical implications. We suggest that sensitive mass spectroscopic studies of ordinary samples containing heavy elements such as lead might reveal the presence of these bound states, as they would appear as anomalously heavy elements. In addition to the effects of single mirror atoms, collective effects from embedded fragments of mirror matter (such as mirror iron microparticles) are also possible. We speculate that such mirror matter fragments might explain a mysterious UV photon burst observed coming from a laser irradiated lead target in a recent experiment.
14009133
Detecting mirror matter on Earth via its thermal imprint on ordinary matter
Mirror matter type dark matter can exist on the Earth's surface, potentially in enhanced concentrations at various anomalous impact sites. Mirror matter fragments can draw in heat from the ordinary matter environment, radiate mirror photons and thereby cool the surrounding ordinary matter. We quantify this effect and suggest that it could be used to help locate mirror matter deposits. This method, together with the centrifuge technique, seems to provide the most promising means to experimentally detect mirror matter type dark matter in the Earth.
16700064
Detecting Dark Matter using Centrifuging Techniques
Abstract A new and inexpensive technique for detecting self interacting dark matter in the form of small grains in bulk matter is proposed. Depending on the interactions with ordinary matter, dark matter grains in bulk matter may be isolated by using a centrifuge and using ordinary matter as a filter. The case of mirror matter interacting with ordinary matter via photon–mirror photon kinetic mixing provides a concrete example of this type of dark matter candidate.
17578958
Mirror matter in the solar system: New evidence for mirror matter from Eros
Abstract Mirror matter is an entirely new form of matter predicted to exist if mirror symmetry is a fundamental symmetry of nature. Mirror matter has the right broad properties to explain the inferred dark matter of the Universe and might also be responsible for a variety of other puzzles in particle physics, astrophysics, meteoritics and planetary science. It is known that mirror matter can interact with ordinary matter non-gravitationally via photon-mirror photon kinetic mixing. The strength of this possibly fundamental interaction depends on the (theoretically) free parameter ϵ . We consider various proposed manifestations of mirror matter in our solar system examining in particular how the physics changes for different possible values of ϵ . We find new evidence for mirror matter in the solar system coming from the observed sharp reduction in crater rates (for craters less than about 100 m in diameter) on the asteroid 433 Eros. We also re-examine various existing ideas including the mirror matter explanation for the anomalous meteorite events, anomalous slow-down of Pioneer spacecraft etc.
53636995
LHC signatures of warped-space vectorlike quarks
A bstractWe study the LHC signatures of TeV scale vectorlike quarks b′, t′ and χ with electromagnetic charges −1/3, 2/3 and 5/3 that appear in many beyond the standard model (BSM) extensions. We consider warped extra-dimensional models and analyze the phenomenology of such vectorlike quarks that are the custodial partners of third generation quarks. In addition to the usually studied pair-production channels which depend on the strong coupling, we put equal emphasis on single production channels that depend on electroweak couplings and on electroweak symmetry breaking induced mixing effects between the heavy vectorlike quarks and standard model quarks. We identify new promising gg-initiated pair and single production channels and find the luminosity required for discovering these states at the LHC. For these channels, we propose a cut that allows one to extract the relevant electroweak couplings. Although the motivation is from warped models, we present many of our results model-independently.
118683255
LHC signatures of a vectorlikeb
Many beyond the standard model extensions predict the existence of heavy vector-like fermions. We study the LHC signatures of one such heavy vector-like fermion, called b', with electromagnetic charge -1/3 like the SM b-quark, but which could generically have different SU(2)_L and U(1)_Y quantum numbers. Our emphasis will be on the phenomenology due to b b' mass-mixing, present after electroweak symmetry breaking. We focus on aspects which distinguish a vector-like b' from a chiral b' and include tree-level decays of the b' into t W, b Z and b h final states. While our analysis is largely model-independent, we take as a motivating example warped-space models in which a vector-like b' appears as the custodial partner of the top-quark.
119291062
Effect of anomalous couplings on the associated production of a single top quark and a Higgs boson at the LHC
A bstractWe consider the production of a single top quark in association with a Higgs boson at the LHC. In particular, we compute the cross sections for the processes pp → thj, thb, thW , thjj, thjb, thW j, thW b in the presence of the anomalous W tb, W W h and tth couplings. We find that the anomalous W tb and tth couplings can enhance the cross sections significantly. We also analyze a few signatures and show that, if these couplings are indeed anomalous, then with enough data, one should be able to observe the production of the Higgs boson in association with single top quark.
53357358
Astrophysical motivation for directed searches for a stochastic gravitational wave background
The nearby Universe is expected to create an anisotropic stochastic gravitational-wave background (SGWB). Different algorithms have been developed and implemented to search for isotropic and anisotropic SGWBs. The aim of this paper is to quantify the advantage of an optimal anisotropic search, specifically comparing a point source with an isotropic background. Clusters of galaxies appear as point sources to a network of ground-based laser-interferometric detectors. The optimal search strategy for these sources is a ``directed radiometer search.'' We show that the flux of SGWBs created by the millisecond pulsars in the Virgo cluster produces a significantly stronger signal than the nearly isotropic background of unresolved sources of the same kind. We compute their strain power spectra for different cosmologies and the distribution of populations over redshifts. We conclude that a localized source, like the Virgo cluster, can be resolved from the isotropic background with very high significance using the directed-search algorithm. For backgrounds dominated by nearby sources, up to a redshift of about 3, we show that the directed search for a localized source can have a signal-to-noise ratio that is greater than that for the all-sky integrated isotropic search.
119239891
Vector meson fragmentation using a model with broken SU(3) at the next-to-leading order
A detailed study of fragmentation of vector mesons at the next-to-leading order (NLO) in QCD is given for e+e- scattering. A model with broken SU(3) symmetry using three input fragmentation functions α(x, Q2), β(x, Q2) and γ(x, Q2) and a strangeness suppression parameter λ describes all the light quark fragmentation functions for the entire vector meson octet. At a starting low energy scale of for three light quarks (u, d, s) along with initial parametrization, the fragmentation functions are evolved through DGLAP evolution equations at NLO and the cross-section is calculated. The heavy quarks contribution are added in appropriate thresholds during evolution. The results obtained are fitted at the momentum scale of for LEP and SLD data. Good-quality fits are obtained for ρ, K*, ω and ϕ mesons, implying the consistency and efficiency of this model. Strangeness suppression in this model is understood both in terms of ratios of quark fragmentation functions alone as well as in terms of observables; the latter yield a suppression through the K*/ρ multiplicity ratio of about 0.23 while the x dependence of this suppression is also parametrized through the cross-section ratios.