Spin transfer in inclusive Lambda0 production by transversely polarized protons at 200-GeV/c.

The E704 collaboration Bravar, A. ; Adams, D.L. ; Akchurin, N. ; et al.
Phys.Rev.Lett. 78 (1997) 4003-4006, 1997.
Inspire Record 449327 DOI 10.17182/hepdata.19560

Surprisingly large polarizations in hyperon production by unpolarized protons have been known for a long time. The spin dynamics of the production process can be further investigated with polarized beams. Recently, a negative asymmetry AN was found in inclusive Λ0 production with a 200GeV/c transversely polarized proton beam. The depolarization DNN in p↑+p→Λ0+X has been measured with the same beam over a wide xF range and at moderate pT. DNN reaches positive values of about 30% at high xF and pT∼1.0GeV/c. This result shows a sizable spin transfer from the incident polarized proton to the outgoing Λ0.

6 data tables

Errors are statistical only. The systematic errors are estimated to be negligible.

Errors are statistical only. The systematic errors are estimated to be negligible.

Errors are statistical only. The systematic errors are estimated to be negligible.

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Measurement of the double spin asymmetry A-LL for inclusive multi gamma pair production with 200-GeV/c polarized proton beam and polarized proton target

The FNAL E581/704 collaboration Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.
Phys.Lett.B 336 (1994) 269-274, 1994.
Inspire Record 378852 DOI 10.17182/hepdata.28569

The invariant double-differential cross section, E 1 E 2 d 6 σ / d p 3 1 d p 3 2 , and the double-spin asymmetry, A LL , for inclusive multi-γ pair production in which γ-rays came from neutral mesons were measured with a 200 GeV / c longitudinally-polarized proton beam and a longitudinally-polarized proton target. Most of the multi-γ pairs comes from two-jet type events which are sensitive to partonic interaction. The A LL values were found to be consistent with zero. The invariant double-differential cross section for inclusive π 0 π 0 production was also measured. These measured cross sections are consistent with LUND Monte Carlo simulations. Using the LUND Monte Carlo simulation package with the Carlitz-Kaur model of spin dependent distribution functions of valence quarks, the A LL values have been compared with theoretical predictions of gluon polarization, ΔG / G . The results put restrictions on the size of ΔG / G in the region of 0.05 ⪅ x ⪅ 0.35.

3 data tables

No description provided.

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MEASUREMENTS OF SPIN CORRELATION PARAMETER A(NN) AND ANALYZING POWER AT 90-degrees FOR P (polarized) P (polarized) ---> D PI+ BETWEEN 500-MEV AND 800-MEV

Glass, G. ; Bhatia, T.S. ; Hiebert, J.C. ; et al.
Phys.Rev.Lett. 53 (1984) 1984-1987, 1984.
Inspire Record 214991 DOI 10.17182/hepdata.20423

Measurements of the spin observables ANN(90∘) and AN0(90∘) for the reaction pp→dπ+ between 500 and 800 MeV are presented and compared with previous measurements and with predictions from theories and a partial-wave analysis. These are the first available measurements of ANN above 590 MeV.

1 data table

ANALYSING POWER IS POL.POL(NAME=AN0).