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Bottomonia in AA collisions…

Bottomonia in AA collisions…. Raphaël Granier de Cassagnac LLR – École polytechnique / IN2P3 ERC grant “ QuarkGluonPlasmaCMS ” SaporeGravi (s) , Dec . 3 rd 2013, Nantes. Quarkonium suppression. Matsui & Satz , PLB168 (1986) 415. Old predicted signature of the QGP

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Bottomonia in AA collisions…

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  1. Bottomonia in AA collisions… Raphaël Granier de Cassagnac LLR – École polytechnique / IN2P3 ERC grant “QuarkGluonPlasmaCMS” SaporeGravi(s), Dec. 3rd2013, Nantes

  2. Quarkonium suppression Matsui & Satz, PLB168 (1986) 415 • Old predicted signature of the QGP • Quarkonia should melt one after the other, depending on their binding energy • Recent example of melting temperatures  • In an ideal world, they could serve as a thermometer of the plasma • With one grade per measured quarkonium… • Potentially five at LHC: ψ, ψ’, Y(1S), Y(2S), Y(3S) ϒ(1S) χb J/ψ, ϒ(2S) χc, χ’b, ψ', ϒ(3S) Mocsy, EPJC61 (2009) 705 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  3. BottomoniavsCharmonia Numbers extracted from various ALICE, CMS and LHCb publications raphael@in2p3.fr - Bottomonia - SaporeGravi(s) • One major drawback • About 200 times less Y(1S)μμ than J/ψμμ • A few advantages, in the thermometer context • Theorists prefer heavier stuff • Less regeneration • More than 100 charm pairs in central PbPb @ 2.76 TeV • Typically 20 times less beauty (was 200 at RHIC) • Y(1S) should be the most plasmaproof (lowest grade) • No feed-down from open flavours, only from higher bottomonia (in particular χb) • Three states close in production x branching ratio • 7 / 2 / 1 (in pp collisions at 7 TeV) • While ψ/ψ’ is more like 50 / 1

  4. BottomoniavsCharmonia Just an illustration… CMS, JHEP 02 (2012) 011 & Phys.Rev.D83:112004,2011 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  5. Feed-down contributions CDF, PRL84 (2000) 2094 LHCb, JHEP11 (2012) 031 raphael@in2p3.fr - Bottomonia - SaporeGravi(s) • Not well known, two measurements at high pT: • CDF @ 1.8 TeV, pT > 8 GeV, |η| < 0.7 (50.9 ± 8.2 ± 9.0)% of Y(1S) coming from feeddown • (27.1 ± 6.9 ± 4.4)% from χb(1P)  ϒ(1S) γ(measured) • (10.5 ± 4.4 ± 1.4)% from χb(2P) ϒ(1S) γ(measured) • (10.7 +7.7–4.8 )% from ϒ(2S)  ϒ(1S) ππ (σ x BR) • (0.8 +0.6–0.4 )% from ϒ(3S) ϒ(1S) ππ(σ x BR) • < 6% from χb(3P) (then unobserved)  ϒ(1S) γ • LHCb @ 7.0 TeV, 6 < pT < 15 GeV, 2.5 < y < 4.0 • (20.7 ± 5.7 ± 2.5 –5.4+2.7)% from χb(1P)  ϒ(1S) γ

  6. Feed-down contributions CDF, PRL84 (2000) 2094 LHCb, JHEP11 (2012) 031 raphael@in2p3.fr - Bottomonia - SaporeGravi(s) • Not well known, two measurements at high pT: • CDF @ 1.8 TeV, pT > 8 GeV, |η| < 0.7 (50.9 ± 8.2 ± 9.0)% of Y(1S) coming from feeddown • (27.1 ± 6.9 ± 4.4)% from χb(1P)  ϒ(1S) γ • (10.5 ± 4.4 ± 1.4)% from χb(2P) ϒ(1S) γ • (10.7 +7.7–4.8 )% from ϒ(2S)  ϒ(1S) ππ • (0.8 +0.6–0.4 )% from ϒ(3S) ϒ(1S) ππ • < 6% from unobserved χb(3P) • LHCb @ 7.0 TeV, 6 < pT < 15 GeV, 2.5 < y < 4.0 • (20.7 ± 5.7 ± 2.5 –5.4+2.7)% from χb(1P)  ϒ(1S) γ

  7. The last feed-down All three χb(1P),(2P)and (3P) ϒ(1S) γ (aka the χb(3P) discovery) DimuonpT > 12 GeV and |y|<2.0 The last contribute less than the two first ATLAS, PRL108 (2012) 341 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  8. Early pA measurements E772, PRL66 (1991) 2285, plots from M. Leitch (Y(1S) also NA50 with less statistics and α ~ 1) raphael@in2p3.fr - Bottomonia - SaporeGravi(s) • E772, Y(1S) & Y(2S+3S) in p+d, C, Ca, Fe & W collisions @ 39 GeV • Less suppression than charmonia • Compatible for 1S and 2S+3S • Including large xF domain • (reminder: σA= σN x Aα) • (warning: the pd reference was not confirmed by E866, but nuclear dependence should be Ok)

  9. A first (preliminary) AA measurement @ RHIC raphael@in2p3.fr - Bottomonia - SaporeGravi(s) • RAA< 0.64 @ 90% • In [9.5;11.5] GeV/c2 • Whatever it was…

  10. Mixed Y(1S+2S+3S) at RHIC in dAu from PHENIX rapidity, d-going side PHENIX, dAu: PRC87 (2013) 044909 raphael@in2p3.fr - Bottomonia - SaporeGravi(s) Statistically very limited…

  11. Mixed Y(1S+2S+3S) at RHIC in AuAu from STAR Also preliminary is RdA(1S+2S+3S) = 0.78 ± 0.28 ± 0.20 Roughly a 50% suppression, that could reflect the melting of the excited states only… STAR preliminary, paper to appear tomorrow on arXiv on AuAu and dAu raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  12. Now, let’s move to the LHC and change the name of the workshop to… raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  13. Now, let’s move to the LHC and change the name of the workshop to… SAPORIBUS GRAVIBUS raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  14. First, an “indication” of Y(2S+3S) suppression The first published paper already had the three states thanks to the first pp run @ 2.76 TeV CMS, PRL107 (2011) 052302 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  15. First, an “indication” of Y(2S+3S) suppression About 2.4σ away from 1 CMS, PRL107 (2011) 052302 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  16. Then, the “observation” Second PbPb run, 20 x more statistics  1S and 2S vs centrality  3S upper limit CMS, PRL109 (2012) 222301 But forget double ratio… raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  17. Nuclear modification factors of 1S, 2S & 3S Sequential disappearance of the 3 states For minimum bias RAA (Y(1S)) = 0.56 ± 0.08 ± 0.07 RAA (Y(2S)) = 0.12 ± 0.04 ± 0.02 RAA (Y(3S)) < 0.10 @ 95% CL Here also, this is not inconsistent with the melting of only the excited states… Nowlet’s look at the kinematics… CMS, PRL109 (2012) 222301 + ALICE, preliminary raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  18. Y(1S) vs y and pT from CMS From CMS results based on the firstPbPb and pp @ 2.76 TeV, I once said: - Need more statistics, but suppression may be localised towards lower pT and y The second PbPb and pp @ 2.76 TeV runs have 20 x more, analysis underway… CMS, JHEP05 (2012) 063 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  19. Y(1S) vs y and pT from CMS+ALICE From ALICE preliminary result, based on the second PbPb run and ppintrapolation: The suppression is not localised at midrapidity CMS, JHEP05 (2012) 063 ALICE, preliminary raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  20. Comparison with theory (1/2) • Multicomponent model: • Proxy for nuclear effect: 0 to 2 mb absorption cross section • Rate equation in the fireball with suppression and regeneration • Reproduce both 1S & 2S • Funny enough a significant part of the very few remaining 2S is attributed to regeneration • Very few Y vs open flavour CMS, PRL109 (2012) 222301 vs. Emerick, Zhao, Rapp, EPJA48 (2012) 72 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  21. Comparison with theory (1/2) • Pure thermal suppression in anisotropic hydro, using CDF feeddowns (51% direct Y(1S)…), no cold effects… Works well for CMS and ALICE separately But predict lower suppression at forward rapidity… CMS, PRL109 (2012) 222301 and ALICE preliminary vs. Strickland, 1205.5327 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  22. Conclusions raphael@in2p3.fr - Bottomonia - SaporeGravi(s) • Just the beginning of bottomonium studies… • At first sight, compatible with maximum melting of excited states, and resilience of the ground state… More PbPb data is needed (so far 50 – 100% centrality) • Kinematical dependencies from existing pp data analysis • But what’s going on in pPb?, see Nicolas’ & Igor’s talks this afternoon… A preview: • A mild suppression (much less than in PbPb) • But a multiplicity dependence, also seen in pp! … that could be due to more activity produced with the ground states  More study vspp multiplicity is needed (e.g., at 7 TeV)

  23. Five grades? Forgetting low pT J/ψand ψ’ (regeneration?) for a while… RAA(MB) vs binding energy looks ordered… TBD with more data vs centrality and unfolding cold effects (pA) & feeddown Could they start acting as a thermometer? Watch out for pT… CMS @ QM’12 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  24. An epitaph for our review? Causaplasma, ad dirumpendo et mutandosaporemgravem raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  25. Back up raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  26. Some xsections raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  27. E772, kinematics raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  28. Upsilon in Au+Au raphael@in2p3.fr - Bottomonia - SaporeGravi(s) • RAA < 0.64 @ 90% • In [9.5;11.5]GeV/c2 • Whatever it is…

  29. The “indication” raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

  30. Alice pp interpolation Bossù @ hard probes 2013 raphael@in2p3.fr - Bottomonia - SaporeGravi(s)

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