[Paper Review] Mini Black Holes at the LHC: Discovery Through Di-Jet Suppression, Mono-Jet Emission and a Supersonic Boom in the Quark-Gluon Plasma in ALICE, ATLAS and CMS

B. Betz, Marcus Bleicher+4 more|ArXiv.org|Jun 19, 2006

Black Holes and Theoretical Physics85 references3 citations

TL;DR

This paper proposes that mini black holes produced in LHC heavy-ion collisions could be detected through di-jet suppression, mono-jet emission, and Mach shock waves in the quark-gluon plasma. It predicts complete suppression of high-$p_T$ back-to-back di-jets above 500 GeV, with subsequent Hawking decay producing hard mono-jets and potential formation of a Heckler-Kapusta-Hawking plasma that generates observable Mach cones.

ABSTRACT

We examine experimental signatures of TeV-mass black hole formation in heavy ion collisions at the LHC. We find that the black hole production results in a complete disappearance of all very high $p_T$ ({$> 500$} GeV) back-to-back correlated di-jets of total mass {$M > M_f \sim 1$}TeV. We show that the subsequent Hawking-decay produces multiple hard mono-jets and discuss their detection. We study the possibility of cold black hole remnant (BHR) formation of mass $\sim M_f$ and the experimental distinguishability of scenarios with BHRs and those with complete black hole decay. Finally we point out that a Heckler-Kapusta-Hawking plasma may form from the emitted mono-jets. In this context we present new simulation data of Mach shocks and of the evolution of initial conditions until the freeze-out.

Motivation & Objective

• To identify experimental signatures of TeV-scale black hole production in heavy-ion collisions at the LHC.
• To distinguish between complete black hole decay and stable black hole remnant (BHR) formation using detector signals.
• To investigate the formation and detectability of a Heckler-Kapusta-Hawking plasma from Hawking-decay products.
• To model hydrodynamic shocks and Mach wave propagation in the quark-gluon plasma induced by mono-jets or BHRs.
• To provide a phenomenological framework for detecting black hole phenomena in ALICE, ATLAS, and CMS experiments.

Proposed method

• Uses the Arkani-Hamed-Dimopoulos-Dvali model with large extra dimensions to estimate black hole production cross sections via classical geometric cross sections.
• Applies parton distribution functions (CTEQ4) and integrates over momentum fractions to compute differential and integrated cross sections for black hole production.
• Models Hawking decay of black holes into multiple hard mono-jets, which can be detected in high-energy collider experiments.
• Simulates hydrodynamic evolution of initial conditions in heavy-ion collisions, including shock wave formation and freeze-out via hadronization criteria.
• Calculates Mach cone angles using the relation $\phi = \arccos(v_s / v_{\text{jet}})$ to predict observable angular correlations in two- and three-particle functions.
• Evaluates BHR propagation through quark-gluon plasma, estimating velocities up to $0.9c$ to assess Mach cone formation.

Experimental results

Research questions

• RQ1 Can the complete suppression of high-$p_T$ back-to-back di-jets ($>500$ GeV) serve as a definitive signature of black hole production in heavy-ion collisions?
• RQ2 How can the presence of a stable black hole remnant (BHR) be experimentally distinguished from complete black hole decay via detector signals in ALICE?
• RQ3 What are the observable hydrodynamic signatures, such as Mach shocks, produced by mono-jets from Hawking decay in the quark-gluon plasma?
• RQ4 Can a Heckler-Kapusta-Hawking plasma form from Hawking radiation and induce detectable blast waves and entropy shifts in the QGP?
• RQ5 Under what conditions can Mach cones be generated by fast-moving black hole remnants or jet-induced shocks in the QGP?

Key findings

• The paper predicts complete suppression of back-to-back di-jets with $p_T > 500$ GeV and invariant mass $M > M_f \sim 1$ TeV, independent of the specific model parameters.
• Black hole decay produces multiple hard mono-jets, which could be detected in ATLAS and CMS, with cross sections ranging from 400 pb to 10 nb for $M_f \sim 1$ TeV and $d = 2$ to $7$ extra dimensions.
• A Heckler-Kapusta-Hawking plasma with initial temperature $500$ GeV can form from Hawking decay and expand into the QGP, increasing entropy and shifting hadronization conditions.
• Hydrodynamic simulations show that jet-induced shocks lead to significant entropy increases, shifting the freeze-out point and reducing baryochemical potential per quark.
• Mach cones are predicted to form with angles $\phi = \arccos(v_s / v_{\text{jet}})$, observable via two- and three-particle correlation functions in ALICE.
• Black hole remnants with mass $M_{\text{BHR}} \sim 1$ TeV can travel at $v_{\text{BHR}} \sim 0.9c$, producing observable Mach cones if moving faster than the QGP sound speed ($c_s \sim 0.57c$).