Low scale gravity black holes at LHC Enikő Regős ( CERN )
Search for Extra Dimensions LHC : Quantum Gravity & Extra Dims LHC : Quantum Gravity & Extra Dims Stringy Quantum Black Holes Stringy Quantum Black Holes Low-scale Gravity Black Holes at LHC Low-scale Gravity Black Holes at LHC Comparison of Black Hole Generators Comparison of Black Hole Generators w De Roeck Gamsizkan Trocsanyi De Roeck Gamsizkan Trocsanyi
Quantum gravity and accelerator physics Obtain limits from collider experiments Obtain limits from collider experiments Graviton interference effects at Large Hadron Collider, CERN Graviton interference effects at Large Hadron Collider, CERN Decay modes of particles with mass in TeV range Decay modes of particles with mass in TeV range Hadron/lepton scatterings and Hadron/lepton scatterings and decays in extra-dimensional models decays in extra-dimensional models Black holes at LHC, CMS Black holes at LHC, CMS Limits from cosmology and astrophysics: cosmic rays and supernovae Limits from cosmology and astrophysics: cosmic rays and supernovae Particle astrophysics Particle astrophysics Dark matter mass of particles, Ex: Axions Ex: Axions Evidence from Evidence from observations for extra D observations for extra D Quantum black holes: energy spectrum, depend on parameters of space times, strings
Cosmic rays and supernovae ; Cosmic rays : Nature’s free collider SN cores emit large fluxes of KK gravitons producing a cosmic background -> radiative decays : diffuse γ – ray background SN cores emit large fluxes of KK gravitons producing a cosmic background -> radiative decays : diffuse γ – ray background Cooling limit from SN 1987A neutrino burst -> bound on radius of extra dimensions Cooling limit from SN 1987A neutrino burst -> bound on radius of extra dimensions Cosmic neutrinos produce black holes, energy loss from graviton mediated interactions cannot explain cosmic ray events above a limit Cosmic neutrinos produce black holes, energy loss from graviton mediated interactions cannot explain cosmic ray events above a limit BH’s in observable collisions of elementary particles if ED BH’s in observable collisions of elementary particles if ED CR signals from mini BH’s in ED, evaporation of mini BHs CR signals from mini BH’s in ED, evaporation of mini BHs
Hierarchy problem & ED Fundamental scales in nature : Fundamental scales in nature : Planck mass : E19 GeV Planck mass : E19 GeV Electroweak scale : 240 GeV Electroweak scale : 240 GeV Supersymmetry : fundamental theory at M_Pl, Supersymmetry : fundamental theory at M_Pl, EW derived ( small #) from dynamics EW derived ( small #) from dynamics Broken ( particle mass ) : gravity mediated Broken ( particle mass ) : gravity mediated gravitino mass determines partner masses gravitino mass determines partner masses EW breaking induced by radiative corrections EW breaking induced by radiative corrections
Extra dimensions EW scale fundamental, M_Pl derived EW scale fundamental, M_Pl derived Compact ED ( radius R ) Compact ED ( radius R ) Matter confined in 4D Matter confined in 4D Gravity : propagates in all D, Gravity : propagates in all D, weak : compact space dimensions large compared to electroweak scale weak : compact space dimensions large compared to electroweak scale G = G_D / (2 π R)^ (D-4) G = G_D / (2 π R)^ (D-4)
Black holes at LHC Event generator for ED BHs : BlackMax I-II Event generator for ED BHs : BlackMax I-II Rotation, fermion splitting, brane tension Rotation, fermion splitting, brane tension Experimental signatures, particle decay Experimental signatures, particle decay CMSSW analysis CMSSW analysis Comparison with Charybdis I-II Comparison with Charybdis I-II Further models of Dvali suggest Black Hole detection even more likely Further models of Dvali suggest Black Hole detection even more likely
Distribution of black hole mass Rotating and non-rotating, 2 ED, 1-5 TeV Rotating and non-rotating, 2 ED, 1-5 TeV
Mass function Log Φ ~ M - M_min Log Φ ~ M - M_min for various models of for various models of Planck mass, ED, M_min, Planck mass, ED, M_min, rotation, brane tension rotation, brane tension
Distribution of BH color (red – blue - green) Rotating and non-rotating, 2 ED, 1-5 TeV Rotating and non-rotating, 2 ED, 1-5 TeV
Distribution of BH charge / 3q / Rotating and non-rotating, 2 ED, 1-5 TeV Rotating and non-rotating, 2 ED, 1-5 TeV
of emitted particles vs. BH mass of emitted particles vs. BH mass Rotating and non-rotating, 2 ED, 5-14 TeV Rotating and non-rotating, 2 ED, 5-14 TeV
Number of emitted particles vs. BH mass during Hawking phase Rotating and non-rotating, 2 ED, 5-14 TeV Rotating and non-rotating, 2 ED, 5-14 TeV
Number of emitted particles vs. # extra dimensions and # fermion splitting dimensions rotating and non-rotating ED = 7 rotating and non-rotating ED = 7
Number of emitted particles / BH vs. brane tension B non-rotating non-rotating ED = 2 ED = TeV 5-14 TeV Hawking phase Hawking phase M_Pl = 1 TeV M_Pl = 1 TeV
Pseudorapidity with final burst Non-rotating and rotating, 2 ED, 1-5 TeV, quarks, anti-quarks, leptons, anti-leptons Non-rotating and rotating, 2 ED, 1-5 TeV, quarks, anti-quarks, leptons, anti-leptons
Lepton transverse momentum : models Planck mass : 2 TeV Planck mass : 2 TeV ED = 3 ED = 3 5 – 14 TeV 5 – 14 TeV Minimum black hole Minimum black hole mass (non-rot) mass (non-rot) Multiplicity decreases w Planck mass Multiplicity decreases w Planck mass Energy & momentum increase Energy & momentum increase
Electrons/positrons, (anti)muons, photons : Transverse momentum & energy spectrum
Pseudorapidity : e - μ - γ Ratio of 0 < ή < 0.5 Ratio of 0 < ή < 0.5 & 0.5 < ή < 1 & 0.5 < ή < 1 distinguishes among beyond standard models distinguishes among beyond standard models All models and species All models and species have values very different from QCD have values very different from QCD
Model comparisons Further models : Planck mass : 2, 5 TeV ED = 5, 3 Minimum mass : 4, 7 TeV Vs. Standard Model top quark transv. momentum /GeV
Analysis at CMS Missing Transverse Energy : Missing Transverse Energy : graviton + neutrino : model dependent graviton + neutrino : model dependent Lepton transverse momentum : Lepton transverse momentum : easy to identify, cuts off for Standard Model easy to identify, cuts off for Standard Model Combined cuts : ή, p_T distribution Combined cuts : ή, p_T distribution
Model settings for detector which have different signature Angular cut for detector acceptance Angular cut for detector acceptance ή_lepton < 2.5 Jets, q, W, Z < 5 ή_lepton < 2.5 Jets, q, W, Z < 5 t, b t, b Implementation of generators in CMSSW Implementation of generators in CMSSW Interface BlackMax II Interface BlackMax II CMSSW : signal and SM background CMSSW : signal and SM background
Comparison of BlackMax with Charybdis BlackMax has higher multiplicity & BlackMax has higher multiplicity & lower momenta lower momenta Missing ET : Missing ET : gravitons only in BlackMax gravitons only in BlackMax BlackMax-II : gravitons in final burst too BlackMax-II : gravitons in final burst too Higher MET Higher MET Apart from cross sections good agreement Apart from cross sections good agreement Yoshino – Rychkov suppression decreases σ Yoshino – Rychkov suppression decreases σ
Multiplicity in BlackMax & Charybdis
Transverse momentum of emitted electrons
Transverse momentum of all particles
Spectrum of emitted electrons
Spectrum of emitted particles
Pseudorapidity of electrons
Pseudorapidity of emitted particles
Missing Transverse Energy with Gravitons
Further models to test at LHC : BHs in Dvali model for SM copies : BHs in Dvali model for SM copies : BH -> SM particle rates different, BH -> SM particle rates different, difference in particle decay difference in particle decay non-integer extra dimension non-integer extra dimension pT, MET pT, MET Dark Matter Dark Matter Even more likely for BHs w ADD & finding them Even more likely for BHs w ADD & finding them
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