Secondary beams Bound-free pair prod. Double bound-free pair prod. A trigger Constrained luminosity Physics interest Bound-free pair production in heavy-ion collisions at high energies Rainer Schicker Phys. Inst., Heidelberg Juni 19, 2015 Rainer Schicker (Heidelberg) Bound-free pair production Juni 19, 2015 1 / 8
Secondary beams Bound-free pair prod. Double bound-free pair prod. A trigger Constrained luminosity Physics interest Secondary ion beams by electromagnetic interactions Bound-free pair production Double bound-free pair production A trigger on electromagnetic processes The bound-free pair constrained photon-photon luminosity Physics interest Rainer Schicker (Heidelberg) Bound-free pair production Juni 19, 2015 2 / 8
Secondary beams Bound-free pair prod. Double bound-free pair prod. A trigger Constrained luminosity Physics interest Secondary Pb-beams at hadron colliders magn. rigidity: Pb 80+ B ρ = Z p 208 A q sec. Pb-beams: Pb 81+ 208 Z 82 A � = 208 Pb 82+ 207 Pb 82+ 206 ✲ cold section: dipoles active collimators: John Jowett, Workshop on photon-induced collisions at the LHC, ◮ at LHC: not possible CERN, june 2-4, 2014 (no space) ◮ at FCC: up for discussion Active collimators - detectors ? Rainer Schicker (Heidelberg) Bound-free pair production Juni 19, 2015 3 / 8
Secondary beams Bound-free pair prod. Double bound-free pair prod. A trigger Constrained luminosity Physics interest Single and multiple pair production single pair production: free e + e − bound-free e + e − σ Born (e + e − ,PbPb,LHC) ∼ 200 kb σ BFPP (PbPb,LHC) ∼ 270 b per beam double bound-free pair production σ 2 xBFPP (PbPb,LHC) > 6 mb (priv. comm. V.Serbo) Rainer Schicker (Heidelberg) Bound-free pair production Juni 19, 2015 4 / 8
Secondary beams Bound-free pair prod. Double bound-free pair prod. A trigger Constrained luminosity Physics interest Multiple pair production production of bound-free pair with a free pair Rainer Schicker (Heidelberg) Bound-free pair production Juni 19, 2015 5 / 8
Secondary beams Bound-free pair prod. Double bound-free pair prod. A trigger Constrained luminosity Physics interest Trigger on electromagnetic processes ☛ ✟ ☛ ✟ ✡ ✠ ✡ ✠ ❈ ❖ ❈ ❖ ✄ � ❈ ❈ ✄ � ❈ ❈ ✂ ✁ ✂ ✁ ✗ ✄ ✄ ✗ ❈ ✄ ❈ ✄ ❈ .. ✄ ❈ .. ✄ .. .. trigger Pb 81+ trigger Pb 81+ central barrel central barrel Forward trigger on Pb 81+ with measurement in central barrel free e + e − , µ + µ − , τ + τ − - pairs π + π − and K + K − - pairs γγ → X → Bound-free pair constrained photon-photon luminosity Rainer Schicker (Heidelberg) Bound-free pair production Juni 19, 2015 6 / 8
Secondary beams Bound-free pair prod. Double bound-free pair prod. A trigger Constrained luminosity Physics interest Bound-free pair constrained photon-photon luminosity Free muon pair production d 2 L ( st ) d ω 1 d ω 2 σ γγ → µµ = dn ( ω 1 ) d σ AA → AA µµ dn ( ω 2 ) d ω 2 = 4 Z 4 α 2 d ω 1 d ω 2 = π 2 ω 1 ω 2 log γ R ω 1 log γ d ω 1 R ω 2 Free muon pair plus bound-free pair production d 2 L bfree dP µµ ( b ) Z 4 α 2 d ω 1 d ω 2 σ γγ → µµ P ee ( b , Z 1 , Z 2 ) d 2 b = π 4 ω 1 ω 2 F ( b ) P ee ( b , Z 1 , Z 2 ) d 2 b d ω 1 d ω 2 = � ∞ d 2 b 1 d 2 b 2 δ ( b 1 − b 2 − b ) ≈ 4 π b 2 log b with F ( b ) = b 2 1 b 2 2 R R 1 integration over b: main contribution from 2 R < b < 1 / m e , where P ee ( b , Z 1 , Z 2 ) ∼ A = 1 . 65 · 10 − 3 (Art. et al) ∗ � 2 � d 2 L bfree d ω 1 d ω 2 = A 4 Z 4 α 2 d 2 L bfree d 2 L st d ω 1 d ω 2 ∼ O (10 − 3 ) 1 log , π 2 ω 1 ω 2 2 Rm e d ω 1 d ω 2 (Art. et al) ∗ : A.N. Artemyev, V.G. Serbo, A. Surzhykov, European Physical Journal C74 (2014), 2829. Rainer Schicker (Heidelberg) Bound-free pair production Juni 19, 2015 7 / 8
Secondary beams Bound-free pair prod. Double bound-free pair prod. A trigger Constrained luminosity Physics interest Physics topics in tagging bound-free secondary beam cross section bound-free pair production ◮ unitarity, Coulomb corrections ? cross section double bound-free pair production ◮ σ (Pb 81+ Pb 81+ ) = 2 x σ (Pb 82+ Pb 80+ ) ? ◮ unitarity, Coulomb corrections ? Multiple lepton pair production Pion/Kaon pair photoproduction γγ → low mass resonances Total γγ -hadronic cross section beyond resonance region γγ → γγ : light-by-light scattering by lepton loops, quark loops or monopole loop. Rainer Schicker (Heidelberg) Bound-free pair production Juni 19, 2015 8 / 8
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