Haim Goldberg

Black Holes from Cosmic Rays: Probes of Extra Dimensions and New Limits on TeV-Scale Gravity

If extra spacetime dimensions and low-scale gravity exist, black holes will be produced in observable collisions of elementary particles. For the next several years, ultrahigh-energy cosmic rays provide the most promising window on this phenomenon. In particular, cosmic neutrinos can produce black holes deep in the Earths atmosphere, leading to quasihorizontal giant air showers. We determine the sensitivity of cosmic ray detectors to black hole production and compare the results to other probes of extra dimensions. With

Dijet Signals for Low Mass Strings at the Large Hadron Collider

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Experimental signature for black hole production in neutrino air showers

extra dimensions, current bounds on deeply penetrating showers from AGASA already provide the most stringent bound on low-scale gravity, requiring a fundamental Planck scale

Cosmic neutrino pevatrons: A brand new pathway to astronomy, astrophysics, and particle physics

{M}_{D}g1.3\char21{}1.8 \mathrm{TeV}.

LHC Phenomenology for String Hunters

The Auger Observatory will probe

Neutrino Bounds on Astrophysical Sources and New Physics

{M}_{D}

A new candidate for dark matter

as large as 4 TeV and may observe on the order of a hundred black holes in 5 years. We also consider the implications of angular momentum and possible exponentially suppressed parton cross sections; including these effects, large black hole rates are still possible. Finally, we demonstrate that even if only a few black hole events are observed, a standard model interpretation may be excluded by comparison with Earth-skimming neutrino rates.

Anomalous baryon number nonconservation in pp collisions at 40 TeV

Assuming that the fundamental string mass scale is in the TeV range and the theory is weakly coupled, we discuss possible signals of string physics at the Large Hadron Collider (LHC). In D-brane constructions, the dominant contributions to full-fledged string amplitudes for all the common QCD parton subprocesses leading to dijets are completely independent of the details of compactification, and can be evaluated in a parameter-free manner. We make use of these amplitudes evaluated near the first resonant pole to determine the discovery potential of LHC for the first Regge excitations of the quark and gluon. Remarkably, the reach of LHC after a few years of running can be as high as 6.8 TeV. Even after the first 100 pb(-1) of integrated luminosity, string scales as high as 4.0 TeV can be discovered. Data on pp-->directgamma + jet can provide corroboration for string physics at scales as high as 5 TeV.

750 GeV diphotons from closed string states

The existence of extra degrees of freedom beyond the electroweak scale may allow the formation of black holes in nearly horizontal neutrino air showers. In this paper we examine the average properties of the light descendants of these black holes. Our analysis indicates that black hole decay gives rise to deeply penetrating showers with an electromagnetic component which differs substantially from that in conventional neutrino interactions, allowing a good characterization of the phenomenon against background. Naturally occurring black holes in horizontal neutrino showers could be detected and studied with the Auger air shower array. Since the expected black hole production rate at Auger is

Breakdown of perturbation theory at tree level in theories with scalars

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