Tagged Neutron candidates observed in MIPP data

T racking D isp lay C alorim eter d isp lay

T agged neu tra l cand idate 2 --58 G eVpp in teraction

4 November 2010 Rajendran Raja, Fermilab PAC 1

Rajendran Raja, Presentation to the Fermilab PAC 2October 19 ,2006

Neutron spectra for various beam momenta

Rajendran Raja, Presentation to the Fermilab PAC 3October 19 ,2006

Proton spectra for various beam momenta

Rajendran Raja, Presentation to the Fermilab PAC 4October 19 ,2006

Pion spectra for various beam momenta

Rajendran Raja, Presentation to the Fermilab PAC 5October 19 ,2006

Expected tagged neutral beam rates

Beam Mom entum Proton Beam K+ beam K- beam Antiproton beamGeV/c n/day K-Long/day K-Long/day anti-n/day

10 20532 4400 4425 665020 52581 9000 9400 1145030 66511 12375 14175 1350060 47069 15750 14125 1355090 37600

Rajendran Raja, Presentation to the Fermilab PAC 6October 19 ,2006

General scaling law of particle fragmentation

• States that the ratio of a semi-inclusive cross section to an inclusive cross section

• where M2,s and t are the Mandelstam variables for the missing mass squared, CMS energy squared and the momentum transfer squared between the particles a and c. PRD18(1978)204.

• Using EHS data, we have tested and verified the law in 12 reactions (DPF92) but only at fixed s.

• MIPP will test this in 36 reactions. MIPP upgrade can extend these scaling relation tests to two particle inclusive reactions which requires more statistics.

f a b c Xf a b c X

f M s tf M s t

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Rajendran Raja, Presentation to the Fermilab PAC 7October 19 ,2006

Other physics interests

High Multiplicity excess due to Bose- Einstein effects in pion emission?

GSI Darmstadt/ KVI are interested in measuring anti-proton cross sections for helping them design the PANDA detector better.

Nuclear physics- y scaling, propagation of strangeness through nuclei. Measure spallation products.

Rajendran Raja, Presentation to the Fermilab PAC 8October 19 ,2006

Missing baryon Resonances• Partial wave analyses of pN scattering have

yielded some of the most reliable information of masses, total widths and pN branching fractions. In order to determine couplings to other channels, it is necessary to study in elastics such as

• All of the known baryon resonances can be described by quark-diquark states. Quark models predict a much richer spectrum. Where are the missing resonances? F.Wilczek, A. Selem

• “..this could form the quantitative foundation for an effective theory of hadrons based on flux tubes”– F.Wilczek

0;; Kpnpnp ppppp

ppKppp ppp ;;0

Rajendran Raja, Presentation to the Fermilab PAC 9October 19 ,2006

Missing Baryon Resonances• Resonances fall into four well defined regions.

» P33(1232) region» c.m energy ~1.5GeV P11(1440)/Roper Resonance,

D13(1520),S11(1535)» c.m. energy of 1.7GeV Nine resonances

S11(1650),D15(1675),F15(1680),D33(1700), P11(1710),P33(1600),S31(1620),D33(1700)» c.m.energy 1.9-2.0GeV. Includes contributions from 7

resonances, most importantly F37(1950). There are approximately nine missing positive-parity resonances in this N=2 band.

• Not much is known above this region. One expects the region near 2.2 GeV to be populated by several N=3 negative parity states and some N=4. MIPP upgrade can explore these regions.

Rajendran Raja, Presentation to the Fermilab PAC 10October 19 ,2006

Missing Baryon Resonances• Reactions which permit coupled

channel partial wave analyses but which need much higher statistics.

• Entire data set for above consist of 241,000 events. Above 1600 MeV PWA becomes noisy, due to low statistics. MIPP will produce an order of magnitude more statistics

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Cascade resonances- MIPP missing mass resolution

MIPP missing mass resolution for the

3/2)(I resonances and