1 / 26

Heavy quark nuclear modification factor: more baryons, less mesons, less energy loss

Heavy quark nuclear modification factor: more baryons, less mesons, less energy loss. Alejandro Ayala Instituto de Ciencias Nucleares UNAM. STAR non-photonic electrons R AA Phys. Rev. Lett. 98 , 192301. Nuclear modification factor R AA. R AA = d 2 N AA /dp  d 

cosima
Download Presentation

Heavy quark nuclear modification factor: more baryons, less mesons, less energy loss

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Heavy quark nuclear modification factor: more baryons, less mesons, less energy loss Alejandro Ayala Instituto de Ciencias Nucleares UNAM

  2. STAR non-photonic electrons RAAPhys. Rev. Lett. 98, 192301

  3. Nuclear modification factor RAA RAA = d2NAA/dpd <Nb> d2Npp/dpd RAA should be ~1 in the absence of medium effects

  4. ALICE non-photonic electrons RAAarXiv:1106.4042 [nucl-ex]

  5. ALICE heavy flavorsarXiv:1106.4042 [nucl-ex]

  6. ALICE heavy flavor RAAarXiv:1106.4042 [nucl-ex] Suppression as strong as for light flavors

  7. STAR proton to pion ratiosnucl-ex/0703040

  8. STAR lambda to kaon ratiosnucl-ex/0601042

  9. RecombinationarXiv:1102.5723 [nucl-th] Low to intermediate pt, falling off exponential Large pt power law fall off

  10. Recombination/coalescence meson momentum p p p1+p2 Parton pt distribution (log scale) (recombination)

  11. baryon momentum p p p1+ p2 + p3 Recombination/coalescence Parton pt distribution (log scale) (recombination) higher yield

  12. Features • quark momenta add to produce a given pT hadrons • soft parton density depends on medium • more quarks for baryons than for mesons • enhanced dependence on centrality for baryons when thermal partons are involved

  13. Is there a relation between the properties of RAA and baryon/meson enhancement? Number of hadrons containing charm in either AA or pp collisions Energy loss

  14. RAA and baryon/meson enhancement relation If heavy flavor baryon/meson is enhanced in AA with respect to pp then there is a source of RAA other than just energy loss Neglectng one gets

  15. Same effect for non-photonic electrons : branching ratio for the decay of heavy flavor meson and baryon into electrons < 1

  16. Same effect for non-photonic electrons < 1 for x < 1 provided baryon/meson is enhanced in AA with respect to pp

  17. Dynamical Recombination Model

  18. Probabilities from dynamical heavy-quark recombination baryons mesons

  19. Charm meson/baryon

  20. D mesons RAA

  21. Non-photonic single electrons RAA

  22. Conclusions • Accounting for medium’s quark momentum redistribution (recombination/coalescence) heavy flavor nuclear modification factors well described without the need of large energy loss in the intermediate pt region. • Overall results independent of model as long as the enhancement of baryon/meson exists in AA with respecto to pp (even for high momentum)

  23. Backup slides

  24. Momentum distributions speed of sound vs2 =1/3, critical temperature Tc = 175 MeV, initial time 0=1 fm, finite transverse expansion velocity vT=0 - 0.4 finial temperature T=100 MeV, initial temperature T=200 MeV.

  25. Momentum distributions

  26. Branching ratios Average between masses of B0 and D0 Average between masses of c and b

More Related