125220211
Vanishing Dimensions and Planar Events at the LHC
We present a paradigm in which the effective dimensionality of space depends on the length scale we are probing. At short scales the space is lower dimensional; at the intermediate scales the space is three-dimensional; and at large scales, the space is effectively higher dimensional. This setup allows for some fundamental problems in cosmology, gravity, and particle physics to be approached from a new perspective and results in striking collider phenomenology. It may also explain elongated jets observed in cosmic-ray data.
119251173
Vanishing Dimensions and Planar Events at the LHC
We propose that the effective dimensionality of the space we live in depends on the length scale we are probing. As the length scale increases, new dimensions open up. At short scales the space is lower dimensional; at the intermediate scales the space is three-dimensional; and at large scales, the space is effectively higher dimensional. This setup allows for some fundamental problems in cosmology, gravity, and particle physics to be attacked from a new perspective. The proposed framework, among the other things, offers a new approach to the cosmological constant problem and results in striking collider phenomenology and may explain elongated jets observed in cosmic-ray data.
11502002
Discovering a light Higgs boson with light
We evaluate the prospects for detecting a non-standard light Higgs boson with a significant branching ratio to two photons, in run II of the Fermilab Tevatron. We derive the reach for several channels: 2{gamma} inclusive, 2{gamma}+1 jet, and 2{gamma}+2 jets. We present the expected run II limits on the branching ratio of h{yields}{gamma}{gamma} as a function of the Higgs boson mass, for the case of ''bosonic,'' as well as ''top-color'' Higgs bosons. (c) 2000 The American Physical Society.
119087457
Rapidity correlations in W gamma production at the tevatron
We study the correlation of photon and charged lepton pseudorapidities, $\eta(\gamma)$ and $\eta(\ell)$, $\ell=e,\,\mu$, in $p\bar p\rightarrow W^\pm\gamma+X\rightarrow \ell^\pm p\llap/_T\gamma+X$ at the Tevatron. In the Standard Model, the $\Delta\eta(\gamma,\ell)= \eta(\gamma) - \eta(\ell)$ differential cross section is found to exhibit a pronounced dip at $\Delta\eta(\gamma,\ell) \approx \mp 0.4$, which originates from the radiation zero present in $q\bar q'\rightarrow W\gamma$. The sensitivity of the $\Delta\eta(\gamma,\ell)$ distribution to higher order QCD corrections, non-standard $WW\gamma$ couplings, and the cuts imposed is explored. The $\Delta\eta(\gamma,\ell)$ distribution is compared with other quantities which are sensitive to the radiation zero.
119417371
Black holes at future colliders and beyond
One of the most dramatic consequences of low-scale (~1 TeV) quantum gravity in models with large or warped extra dimension(s) is copious production of mini-black holes at future colliders and in ultra-high-energy cosmic ray collisions. Hawking radiation of these black holes is expected to be constrained mainly to our three-dimensional world and results in rich phenomenology. In this topical review we discuss the current status of astrophysical observations of black holes and selected aspects of mini-black-hole phenomenology, such as production at colliders and in cosmic rays, and black-hole decay properties, Hawking radiation as a sensitive probe of the dimensionality of extra space, as well as an exciting possibility of finding new physics in the decays of black holes.
16891404
Drell-Yan and diphoton production at hadron colliders and low scale gravity model
In the model of Arkani-Hamed, Dimopoulos, and Dvali where gravity is allowed to propagate in the extra dimensions of very large size, virtual graviton exchange between the standard model particles can give rise to signatures that can be tested in collider experiments. We study these effects in dilepton and diphoton production at hadron colliders. Specifically, we examine the double differential cross section in the invariant mass and scattering angle, which is found to be useful in separating the gravity effects from the standard model. In this work, sensitivity obtained using the double differential cross section is higher than that in previous studies based on single differential distributions. Assuming no excess of events over the standard model predictions, we obtain the following 95% confidence level lower limits on the effective Planck scale: 0.9\char21{}1.5 TeV in the Fermilab Tevatron run I, 1.3\char21{}2.5 TeV in run IIa, 1.7\char21{}3.5 TeV in run IIb, and 6.5\char21{}12.8 TeV at the CERN LHC. The range of numbers corresponds to the number of extra dimensions $n=7\ensuremath{-}2.$
115236552
Searches for exotic pentaquark baryons with hidden strangeness in experiments at the SPHINX facility