Status of 2D hadron attenuation paper

1. Status of 2D hadron attenuation paper Z. Akopov for DC_73

2. Motivation/Results In addition to Long paper, performed 2D analysis for Neon, Krypton and Xenon for all charged hadrons separately: • Nu, Q2, pt2 and Lc in 3 z-ranges • Z,Q2,pt2 and Lc in 3 nu-ranges • Nu,z,Q2 and Lc in 2 pt2-ranges • 1D Lc dependence

3. Results overview • Normally attenuation goes to 1; for proton in heavier targets – different behavior – slope changes. • Should be reflected/accounted for in model calculations

4. Results overview • Tendency seen for pions, remains for K,p • At leading z, little to no broadening

5. Results overview • Nu-dependency • As opposed to pions, amplification at high pt2 on heavier targets • Rescattering, more protons. • Models have to explain

6. Results overview • When divide in z-ranges, no more scaling for proton! • Slopes different

7. Results overview • Anti-protons – similar to pions and co.

8. Results overview • Different hN x-section for K+/K- and p/anti-p, well reflected • Otherwise, for each charge scaling remains.

9. Questions imposed to paper • Are we able to explain the features of 2d-dependencies just based on published 1d data? • What can be achieved using the 2d-data for all charged hadrons and how useful is that for theory?

10. Arguments • Clear difference between super-ratio for positive/negative hadrons, i.e. kaons and protons • Lc dependence data for various kinematic ranges, gives solid experimental proof of different production mechanisms of proton as opposed to other hadrons • Important: such behavior is not possible to predict based on the published data: interpretation of these new data should motivate new approaches to theoretical threatment of hadronization

11. Conclusion • HERMES possesses new set of results that are clearly needed on the market. • Either separate paper to present these results, or an addendum to the Long NA paper.