Sub Threshold strange hadron production in UrQMD

Sub Threshold strange hadron production in UrQMD Jan Steinheimer and Marcus Bleicher 10.05.2016 Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 1 / 26

Motivation Recent measurements on near and below threshold production. 0.8 0.6 HADES preliminary production threshold in elementary p+p UrQMD, Au+Au, central, y <0.5 Data φ production HADES and FOPI reported unexpected large φ contribution to the K yield. /K - 0.4 FOPI HADES 0.2 E917 NA49 0.0 2 10 s NN [GeV] G. Agakishiev et al. [HADES Collaboration], Phys. Rev. C 80, 025209 (2009) an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 2 / 26

Motivation Recent measurements on near and below threshold production. φ production HADES and FOPI reported unexpected large φ contribution to the K yield. Ξ production Ξ yield, measured in Ar+KCl much larger than thermal model. Confirmed in p+nb No Y+Y exchange!! G. Agakishiev et al. [HADES Collaboration], Phys. Rev. Lett. 103, 132301 (2009) an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 2 / 26

Motivation Recent measurements on near and below threshold production. φ production HADES and FOPI reported unexpected large φ contribution to the K yield. Ξ production Ξ yield, measured in Ar+KCl much larger than thermal model. Confirmed in p+nb No Y+Y exchange!! Both particles are not well described in microscopic transport models and thermal fits are also not convincing. G. Agakishiev et al. [HADES Collaboration], Phys. Rev. Lett. 103, 132301 (2009) Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 2 / 26

The notorious φ + N cross section Does the φ have a small hadronic cross section? The idea that the φ has a small hadronic cross section is not new. A. Shor, Phys. Rev. Lett. 54, 1122 (1985). The φ would be an important probe of hadronization. COSY and LEPS experiments have found large nuclear absorption cross sections ANKE SPring-8 14-21 mb 35 mb M. Hartmann et al., Phys. Rev. C 85, 035206 (2012) T. Ishikawa et al., Phys. Lett. B 608, 215 (2005) an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 3 / 26

The extracted cross sections depend on model assumptions SPring-8 Used a Glauber model for the absorption. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 4 / 26

The extracted cross sections depend on model assumptions SPring-8 Used a Glauber model for the absorption. ANKE 1: The eikonal approximation of the Valencia group. 2: Paryev developed the spectral function approach for φ production in both the primary proton- nucleon and secondary pion nucleon channels. BUU transport calculation of the Rossendorf group. Accounts for baryon baryon and meson baryon φ production processes. R=(12/A)(σ A φ /σ C φ ) 0.8 0.6 0.4 0.6 0.4 0.2 0.4 0.2 Cu/C Ag/C Au/C 0.5 1 2 4 0.5 1 2 4 0.5 1 2 4 0.4 0.2 Cu/C Ag/C Au/C 300.6 73 120 200 0.4 30 0.8 0.6 730.4 120 200 0.2 30 0.4 73 120 0.2 Cu/C Ag/C Au/C 10 20 30 10 15 30 10 15 25 0.5 1.0 1.5 0.5 1.0 1.5 p [GeV/c] φ 0.5 1.0 1.5 an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 4 / 26

The Kaon-Nuclear potential 5 4 a) b) Al+Al 1.9A GeV K - /K + (%) 3 2 1 0 U K +(ρ 0 )=40 MeV U K -(ρ 0,p=0) -50 MeV NO Pot. 0.1 0.15 0.2 U K +(ρ 0 )=40 MeV, no K - Pot. 0.1 0.15 0.2 An example E kin (GeV) CM P. Gasik et al. [FOPI Collaboration], arxiv:1512.06988 [nucl-ex]. The K /K + ratio is used to determine the Kaon nuclear potentials. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 5 / 26

The Kaon-Nuclear potential 5 4 a) b) Al+Al 1.9A GeV K - /K + (%) 3 2 1 0 U K +(ρ 0 )=40 MeV U K -(ρ 0,p=0) -50 MeV NO Pot. 0.1 0.15 0.2 U K +(ρ 0 )=40 MeV, no K - Pot. 0.1 0.15 0.2 An example E kin (GeV) CM P. Gasik et al. [FOPI Collaboration], arxiv:1512.06988 [nucl-ex]. The K /K + ratio is used to determine the Kaon nuclear potentials. Quantitative result relies on the baseline of non-potential case. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 5 / 26

The Kaon-Nuclear potential 5 4 a) b) Al+Al 1.9A GeV K - /K + (%) 3 2 1 0 U K +(ρ 0 )=40 MeV U K -(ρ 0,p=0) -50 MeV NO Pot. 0.1 0.15 0.2 U K +(ρ 0 )=40 MeV, no K - Pot. 0.1 0.15 0.2 An example E kin (GeV) CM P. Gasik et al. [FOPI Collaboration], arxiv:1512.06988 [nucl-ex]. The K /K + ratio is used to determine the Kaon nuclear potentials. Quantitative result relies on the baseline of non-potential case. φ contribution to the K found to be important. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 5 / 26

Why is a sub threshold charm prediction interesting? Charm at high baryon densities Study properties of charmed hadrons in dense nuclear matter. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 6 / 26

Why is a sub threshold charm prediction interesting? Charm at high baryon densities Study properties of charmed hadrons in dense nuclear matter. Study hadronic charm rescattering. Study charm in cold nuclear matter. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 6 / 26

Why is a sub threshold charm prediction interesting? Charm at high baryon densities Study properties of charmed hadrons in dense nuclear matter. Study hadronic charm rescattering. Study charm in cold nuclear matter. Big part of CBM program...but that was SIS300! Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 6 / 26

Why is a sub threshold charm prediction interesting? Charm at high baryon densities Study properties of charmed hadrons in dense nuclear matter. Study hadronic charm rescattering. Study charm in cold nuclear matter. Big part of CBM program...but that was SIS300! SIS100 p+p->j/ +X p+p-> C +D+X p+p->d+d+x tot [nb] s NN [GeV] Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 6 / 26

UrQMD UrQMD is a microscopic transport model We will use it in cascade mode. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 7 / 26

UrQMD UrQMD is a microscopic transport model We will use it in cascade mode. Particles follow a straight line until they scatter. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 7 / 26

UrQMD UrQMD is a microscopic transport model We will use it in cascade mode. Particles follow a straight line until they scatter. No long range interactions like potentials. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 7 / 26

Strangeness Production in UrQMD UrQMD is a microscopic transport model Only 2 2, 2 1, 2 N and 1 N interactions allowed. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 8 / 26

Strangeness Production in UrQMD UrQMD is a microscopic transport model Only 2 2, 2 1, 2 N and 1 N interactions allowed. Resonance decays according to PDG values + guesstimates. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 8 / 26

Strangeness Production in UrQMD UrQMD is a microscopic transport model Only 2 2, 2 1, 2 N and 1 N interactions allowed. Resonance decays according to PDG values + guesstimates. Detailed balance. (Violated in string excitations, annihilations and some dacays) an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 8 / 26

Strangeness Production in UrQMD Relevant channels: Strange particle production goes ONLY via Resonance excitation: N+N X N+M X M+M X 1 NN N 1232 2 NN NN 3 NN N 4 NN 1232 1232 5 NN 1232 N 6 NN 1232 7 NN R R an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 9 / 26

Strangeness Production in UrQMD Strange particle production goes ONLY via Resonance excitation: N+N X N+M X M+M X N*(1650) N*(1710) N*(1720) N*(1875) N*(1900) N*(1990) N*(2080) N*(2190) N*(2220) N*(2250) N*(2600) N*(2700) N*(3100) N*(3500) N*(3800) N*(4200) (1232) (1600) (1620) (1700) (1900) (1905) (1910) (1920) (1930) (1950) (2440) (2750) (2950) (3300) (3500) (4200) an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 9 / 26

Strangeness Production in UrQMD Strange particle production goes ONLY via Resonance excitation: N+N X N+M X M+M X [mb] 80 10 1 PDG elastic PDG total UrQMD total elastic inelastic string double resonance p+p 2 3 4 5 6 7 8 9 10 s NN [GeV] N+N Cross section with σ 1,2 3,4( s) (2S 3 + 1)(2S 4 + 1) p3,4 M(m3, m4) 2 p 1,2 M(m3, m4) 2 = A (m 4 m 3) 2 (m 4 + m 3) 2 an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 9 / 26

Strangeness exchange reactions In addition Strange hadrons may be created in strangeness exchange reactions. 100 p+k - + + - p+k - ( 0 + )+ 0 80 p+k - - + + [mb] 60 40 20 0 0.00 0.02 0.04 0.06 s- s 0 [GeV] Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 10 / 26

First the φ Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 11 / 26

On the probability of sub threshold production Sub-threshold production in UrQMD Fermi momenta lift the collision energy above the threshold. Secondary interactions accumulate energy. dn/dm (normalized) (a) Ca+Ca, E lab =1.76 A GeV, b>9 fm (b) Ca+Ca, E lab =1.76 A GeV, b=0 fm (c) Be+Be, E lab =1.76 A GeV, b=0 fm 10 1 Maximal available Mass from initial scatterings Actual Mass of N* from initial scatterings Mass of all N* decaying 10 0 10-1 N* N+ N* + + N* N+ N* + + N* N+ N* + + 10 1 10 0 10-1 10-2 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 Invariant mass M [GeV] 10-2 an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 12 / 26

On the probability of sub threshold production Sub-threshold production in UrQMD Fermi momenta lift the collision energy above the threshold. Secondary interactions accumulate energy. dn/dm (normalized) (a) Ca+Ca, E lab =1.76 A GeV, b>9 fm (b) Ca+Ca, E lab =1.76 A GeV, b=0 fm (c) Be+Be, E lab =1.76 A GeV, b=0 fm 10 1 Maximal available Mass from initial scatterings Actual Mass of N* from initial scatterings Mass of all N* decaying 10 0 10-1 N* N+ N* + + N* N+ N* + + N* N+ N* + + 10 1 10 0 10-1 10-2 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 Invariant mass M [GeV] 10-2 Why not introduce these decays for the less known resonances? an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 12 / 26

Fixing the N φ + N decay with p+p data We use ANKE data on the φ production cross section to fix the N N + φ branching fraction. ANKE data UrQMD p+p p+p+ [nb] production threshold Only 1 parameter Γ N Nφ/Γ tot = 0.2% Fits all 3 points! E lab [GeV] A. Sibirtsev, J. Haidenbauer and U. G. Meissner, Eur. Phys. J. A 27, 263 (2006) [arxiv:nucl-th/0512055]. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 13 / 26

Fixing the N φ + N decay with p+p data We use ANKE data on the φ production cross section to fix the N N + φ branching fraction. ANKE data UrQMD p+p p+p+ [nb] production threshold Only 1 parameter Γ N Nφ/Γ tot = 0.2% Fits all 3 points! E lab [GeV] Branching fraction consistent with extracted OZI suppression (from ω/φ) Y. Maeda et al. [ANKE Collaboration], Phys. Rev. C 77, 015204 (2008) [arxiv:0710.1755 [nucl-ex]]. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 13 / 26

φ suppression in nuclear medium Detailed balance absorption cross section dσ b a p 2 dω = a (2S 1 + 1)(2S 2 + 1) p 2 b (2S 3 + 1)(2S 4 + 1) J + j 1m 1j 2m 2 JM dσ a b j J=J 3m 3j 4m 4 JM 2 dω 2 φ + p cross section from detailed balance is very small. inel [mb] 100 10 1 +p K - +p 0.1 0.00 0.05 0.10 0.15 s- s [GeV] 0.20 0.25 Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 14 / 26

φ suppression in nuclear medium 0.6 φ + p cross section from detailed balance is very small. Still the transparency ratio is well reproduced. Remember: this is what lead to the 20 mb cross section from ANKE. R=(12/A) ( A / C ) 0.5 0.4 0.3 0.2 0.1 Au/C Ag/C Cu/C 0.0 0.6 0.8 1.0 1.2 1.4 1.6 p [GeV/c] Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 14 / 26

φ suppression in nuclear medium 0.6 0.5 φ + p cross section from detailed balance is very small. Still the transparency ratio is well reproduced. Remember: this is what lead to the 20 mb cross section from ANKE. Even the shape of the spectra looks good. R=(12/A) ( A / C ) d 2 /dp d [ b/(sr GeV/c)] 0.4 0.3 0.2 0.1 Au/C Ag/C Cu/C 0.0 0.6 0.8 1.0 1.2 1.4 1.6 p [GeV/c] 100 80 60 40 20 p+c p+cu p+ag p+au 0 0.0 0.4 0.8 1.2 1.6 p [GeV/c] Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 14 / 26

φ suppression in nuclear medium 0.6 φ + p cross section from detailed balance is very small. Still the transparency ratio is well reproduced. Remember: this is what lead to the 20 mb cross section from ANKE. Even the shape of the spectra looks good. Not absorption of the φ, but of the mother resonance. Reactions of the type: N + N N + N N + N N + N where the mass of N < N so no φ can be produced. R=(12/A) ( A / C ) d 2 /dp d [ b/(sr GeV/c)] 0.5 0.4 0.3 0.2 0.1 Au/C Ag/C Cu/C 0.0 0.6 0.8 1.0 1.2 1.4 1.6 p [GeV/c] 100 80 60 40 20 p+c p+cu p+ag p+au 0 0.0 0.4 0.8 1.2 1.6 p [GeV/c] Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 14 / 26

φ production in nuclear collisions below the p+p threshold When applied to nuclear collisions: HADES preliminary production threshold in elementary p+p UrQMD, Au+Au, central, y <0.5 Data /K - FOPI HADES E917 NA49 s NN [GeV] an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 15 / 26

φ production in nuclear collisions below the p+p threshold When applied to nuclear collisions: /K - HADES preliminary production threshold in elementary p+p FOPI HADES UrQMD, Au+Au, central, y <0.5 Data Qualitative behavior nicely reproduced Predicted maximum at 1.25 A GeV E917 NA49 s NN [GeV] an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 15 / 26

φ production in nuclear collisions below the p+p threshold When applied to nuclear collisions: /K - HADES preliminary production threshold in elementary p+p FOPI HADES E917 UrQMD, Au+Au, central, y <0.5 Data NA49 Qualitative behavior nicely reproduced Predicted maximum at 1.25 A GeV High energies: too low due to string production s NN [GeV] HADES preliminary results for 1.23 A GeV, see HADES DPG talk. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 15 / 26

φ production in nuclear collisions below the p+p threshold Even centrality dependence works well: /K - E lab =1.93 A GeV Ni+Ni UrQMD FOPI Data (a) (b) / + x 1000 <A part > Data from: K. Piasecki et al., arxiv:1602.04378 [nucl-ex]. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 16 / 26

φ production in nuclear collisions below the p+p threshold Even centrality dependence works well: /K - / + x 1000 E lab =1.93 A GeV Ni+Ni UrQMD FOPI Data (a) (b) Centrality dependence nicely reproduced. Good indicator for multi step production. <A part > Data from: K. Piasecki et al., arxiv:1602.04378 [nucl-ex]. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 16 / 26

About the Kaon potential Kaon Potentials To constrain the Kaon potentials from kaon spectra one needs to understand the baseline For example the φ contribution to the K. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 17 / 26

About the Kaon potential Kaon Potentials To constrain the Kaon potentials from kaon spectra one needs to understand the baseline For example the φ contribution to the K. But also the general shape of the spectra may depend on the model. K - /K + [%] FOPI data with FOPI data w/o UrQMD with UrQMD w/o E kin CM [GeV] Al+Al, E lab =1.93 A GeV UrQMD results K /K + ratio as function of Kaon energy. With and without the φ the ratio is much closer to the data already as in a comparable study with K potential. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 17 / 26

About the Kaon potential Kaon Potentials To constrain the Kaon potentials from kaon spectra one needs to understand the baseline For example the φ contribution to the K. But also the general shape of the spectra may depend on the model. K - /K + [%] FOPI data with FOPI data w/o UrQMD with UrQMD w/o E kin CM [GeV] Al+Al, E lab =1.93 A GeV UrQMD results K /K + ratio as function of Kaon energy. With and without the φ the ratio is much closer to the data already as in a comparable study with K potential. Can we make robust quantitative statements? an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 17 / 26

Now the Ξ Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 18 / 26

How to fix the N Ξ + K + K decay? No elementary measurements near threshold. We use p+nb at E lab = 3.5 GeV data Γ N Ξ+K+K/Γ tot = 3.0% Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 19 / 26

How to fix the N Ξ + K + K decay? No elementary measurements near threshold. We use p+nb at E lab = 3.5 GeV data Γ N Ξ+K+K/Γ tot = 3.0% HADES data Ξ Ξ /Λ (2.0 ± 0.3 ± 0.4) 10 4 (1.2 ± 0.3 ± 0.4) 10 2 UrQMD Ξ Ξ /Λ (1.44 ± 0.05) 10 4 (0.71 ± 0.03) 10 2 Table: Ξ production yield and Ξ /Λ ratio for minimum bias p + Nb collision at a beam energy of E lab = 3.5 GeV, compared with recent HADES results Note: G. Agakishiev et al., arxiv:1501.03894 [nucl-ex]. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 19 / 26

How to fix the N Ξ + K + K decay? No elementary measurements near threshold. We use p+nb at E lab = 3.5 GeV data Γ N Ξ+K+K/Γ tot = 3.0% HADES data Ξ Ξ /Λ (2.0 ± 0.3 ± 0.4) 10 4 (1.2 ± 0.3 ± 0.4) 10 2 UrQMD Ξ Ξ /Λ (1.44 ± 0.05) 10 4 (0.71 ± 0.03) 10 2 Table: Ξ production yield and Ξ /Λ ratio for minimum bias p + Nb collision at a beam energy of E lab = 3.5 GeV, compared with recent HADES results Note: Branching ratio seems large, however may be contributed to the limited number of heavy states in the model. G. Agakishiev et al., arxiv:1501.03894 [nucl-ex]. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 19 / 26

Ξ production in nuclear collisions below the p+p threshold 10 0 10-1 10-2 10-3 10-4 10-5 10-6 10-7 Ca+Ca E lab = 1.76 A GeV, b<5 fm; full acceptance K + / + K - / - K - /K + HADES data UrQMD with Y+Y exchange UrQMD with new decays - / / - / / 10 0 10-1 10-2 10-3 10-4 10-5 10-6 10-7 Ξ yield in Ar+KCl collisions is nicely reproduced Consistent with the p+nb data. Indication for Ξ production from non-thermal tails of particle production. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 20 / 26

Ξ production in nuclear collisions below the p+p threshold 10 0 10-1 10-2 10-3 10-4 10-5 10-6 10-7 Ca+Ca E lab = 1.76 A GeV, b<5 fm; full acceptance K + / + K - / - K - /K + HADES data UrQMD with Y+Y exchange UrQMD with new decays - / / - / / 10 0 10-1 10-2 10-3 10-4 10-5 10-6 10-7 Ξ yield in Ar+KCl collisions is nicely reproduced Consistent with the p+nb data. Indication for Ξ production from non-thermal tails of particle production. All other strange particle ratios are also in line with experiment an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 20 / 26

Predictions for Au+Au at E lab = 1.23 A GeV 10 0 Au+Au E lab = 1.23 A GeV, K + / + K - / - K - /K + - / / - / 10 0 10-1 / 10-1 10-2 10-2 10-3 10-4 10-3 10-4 Ξ /Λ does not decrease much. 10-5 10-6 10-7 1.23 A GeV Au+Au: HADES - PRELIMINARY, mid-y UrQMD with new decays: E lab = 1.23 A GeV Au+Au, y <0.1, b<9.5 fm E lab = 1.76 A GeV Ca+Ca, all-y, b<5 fm 10-5 10-6 10-7 Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 21 / 26

Can we make predictions about sub threshold charm production? Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 22 / 26

Fixing the N J/Ψ + N decay with p+p data We use data from p+p at s = 6.7 GeV to fix the N N + J/Ψ branching fraction. SIS100 p+p->j/ +X p+p-> C +D+X p+p->d+d+x Assumptions tot [nb] p+p->j/ +X UrQMD Data p+p-> C +D+X UrQMD Only 1 parameter s NN [GeV] Γ N NJΨ/Γ tot = 2.5 10 5 Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 23 / 26

Fixing the N J/Ψ + N decay with p+p data We use data from p+p at s = 6.7 GeV to fix the N N + J/Ψ branching fraction. Assumptions tot [nb] SIS100 p+p->j/ +X UrQMD Data p+p-> C +D+X UrQMD p+p->j/ +X p+p-> C +D+X p+p->d+d+x We assume the associated production of N Λ c + D to be a factor 15 larger at that beam energy and to contribute about the half of the total charm production. Only 1 parameter s NN [GeV] Γ N NJΨ/Γ tot = 2.5 10 5 Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 23 / 26

Fixing the N J/Ψ + N decay with p+p data We use data from p+p at s = 6.7 GeV to fix the N N + J/Ψ branching fraction. tot [nb] SIS100 p+p->j/ +X UrQMD Data p+p-> C +D+X UrQMD p+p->j/ +X p+p-> C +D+X Only 1 parameter p+p->d+d+x s NN [GeV] Γ N NJΨ/Γ tot = 2.5 10 5 Assumptions We assume the associated production of N Λ c + D to be a factor 15 larger at that beam energy and to contribute about the half of the total charm production. We neglect D + D pair production as it has a significantly higher threshold Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 23 / 26

Fixing the N J/Ψ + N decay with p+p data We use data from p+p at s = 6.7 GeV to fix the N N + J/Ψ branching fraction. tot [nb] SIS100 p+p->j/ +X UrQMD Data p+p-> C +D+X UrQMD p+p->j/ +X p+p-> C +D+X Only 1 parameter p+p->d+d+x s NN [GeV] Γ N NJΨ/Γ tot = 2.5 10 5 Assumptions We assume the associated production of N Λ c + D to be a factor 15 larger at that beam energy and to contribute about the half of the total charm production. We neglect D + D pair production as it has a significantly higher threshold We neglect string production Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 23 / 26

Fixing the N J/Ψ + N decay with p+p data We use data from p+p at s = 6.7 GeV to fix the N N + J/Ψ branching fraction. tot [nb] SIS100 p+p->j/ +X UrQMD Data p+p-> C +D+X UrQMD p+p->j/ +X p+p-> C +D+X Only 1 parameter p+p->d+d+x s NN [GeV] Γ N NJΨ/Γ tot = 2.5 10 5 Assumptions We assume the associated production of N Λ c + D to be a factor 15 larger at that beam energy and to contribute about the half of the total charm production. We neglect D + D pair production as it has a significantly higher threshold We neglect string production All the contributions should even increase the expected yield. Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 23 / 26

J/Ψ suppression in nuclear medium Detailed balance absorption cross section J/Ψ + p cross section from detailed balance is very small. inel [mb] 100 10 1 0.1 0.01 1E-3 K - +p +p J/ +p 1E-4 0.00 0.05 0.10 0.15 0.20 0.25 s- s [GeV] Comparable to: D. Kharzeev and H. Satz, Phys. Lett. B 334, 155 (1994). an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 24 / 26

J/Ψ suppression in nuclear medium Detailed balance absorption cross section J/Ψ + p cross section from detailed balance is very small. Not absorption of the J/Ψ, but of the mother resonance. Reactions of the type: N + N N + N N + N N + N where the mass of N < N so no J/Ψ can be produced. inel [mb] 100 10 1 0.1 0.01 1E-3 K - +p +p J/ +p 1E-4 0.00 0.05 0.10 0.15 0.20 0.25 s- s [GeV] Comparable to: D. Kharzeev and H. Satz, Phys. Lett. B 334, 155 (1994). an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 24 / 26

J/Ψ and open charm production in nuclear collisions below the p+p threshold When applied to central nuclear collisions (min. bias: divide by 5): Total Multiplicity SIS100 p+p->j/ +X p+p-> C +D+X p+p->d+d+x p+p J/ C Au+Au central J/ C E lab = 6 A GeV 3 10 7 J/Ψ per event or 3 10 4 in 10 weeks 4 10 6 Λ c per event or 121 in 10 weeks 6 8 10 6 D per event s NN [GeV] Measured yields are according to specifications in The CBM physics book Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 25 / 26

J/Ψ and open charm production in nuclear collisions below the p+p threshold When applied to central nuclear collisions (min. bias: divide by 5): Total Multiplicity SIS100 p+p->j/ +X p+p-> C +D+X p+p->d+d+x p+p J/ C Au+Au central J/ C E lab = 11 A GeV 1.5 10 6 J/Ψ per event or 1.5 10 5 in 10 weeks 2 10 5 Λ c per event or 600 in 10 weeks 3 4 10 5 D per event s NN [GeV] Measured yields are according to specifications in The CBM physics book Jan Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 25 / 26

Summary We introduced a new mechanism of φ and Ξ production in elementary and nuclear collisions, through the decay of heavy resonances. We can nicely describe the φ and Ξ production in elementary and nuclear collisions near and below the φ production threshold. To successfully describe Ξ production in p+pb and Ar+KCl reactions a large branching fraction of 10% is required. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 26 / 26

Summary We introduced a new mechanism of φ and Ξ production in elementary and nuclear collisions, through the decay of heavy resonances. We can nicely describe the φ and Ξ production in elementary and nuclear collisions near and below the φ production threshold. To successfully describe Ξ production in p+pb and Ar+KCl reactions a large branching fraction of 10% is required. For the first time we made predictions for sub threshold J/Ψ, Λ c and D production in sub threshold collisions at the SIS100. an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 26 / 26

Backup dn/de kin /dcos( ) x CM CM 10-2 [1/GeV] 10 8 6 4 K + Al+Al, E lab =1.93 A GeV 2 UrQMD with UrQMD w/o FOPI data 0 0.00 0.05 0.10 0.15 0.20 0.25 0.30 E kin CM [GeV] dn/de kin /dcos( ) x CM CM 10-3 [1/GeV] UrQMD with UrQMD w/o FOPI data E kin CM [GeV] Al+Al, E lab =1.93 A GeV K - an Steinheimer and Marcus Bleicher (FIAS) 10.05.2016 26 / 26