Measurement of single spin asymmetry for direct photon production in p p collisions at 200-GeV/c

The E704 collaboration Adams, D.L. ; Achurin, N. ; Belikov, N.I. ; et al.
Phys.Lett.B 345 (1995) 569-575, 1995.
Inspire Record 399938 DOI 10.17182/hepdata.28766

The single spin asymmetry for inclusive direct-photon production has been measured using a polarized proton beam of 200 GeV/c with an unpolarized proton target at −0.15 < xf < 0.15 and 2.5 < pt < 3.1 GeV/c at Fermilab. The data on the cross section for pp → γX at 2.5 < pt < 3.8 GeV/c are also provided. The measurement was done using lead-glass calorimeters and photon detectors which surrounded the fiducial area of the calorimeters. Background rejection has been done using these surrounding photon detectors. The cross section obtained is consistent with the results of previous measurements assuming a nuclear dependence of A 1.0 . The single spin asymmetry, A N , for the direct-photon production is consistent with zero within experimental uncertainty.

2 data tables

No description provided.

No description provided.


Analyzing power measurement in inclusive Lambda0 production with a 200-GeV/c polarized proton beam

The E704 collaboration Bravar, A. ; Adams, D.L. ; Akchurin, N. ; et al.
Phys.Rev.Lett. 75 (1995) 3073-3077, 1995.
Inspire Record 406598 DOI 10.17182/hepdata.19610

The considerable polarization of hyperons produced at high xF has been known for a long time and has been interpreted with various theoretical models in terms of the constituents' spin. Recently, the analyzing power in inclusive Λ0 hyperon production has also been measured using the 200GeV/c Fermilab polarized proton beam. The covered kinematic range is 0.2≤xF≤1.0 and 0.1≤pT≤1.5GeV/c. The data indicate a negative asymmetry at large xF and moderate pT. These results can further test the current ideas on the underlying mechanisms for hyperon polarization.

6 data tables

No description provided.

No description provided.

No description provided.

More…

High $\chi_t$ Single Spin Asymmetry in $\pi^0$ and $\eta$ Production at $\chi_F$ = 0 by 200 GeV Polarized Antiprotons and Protons

The E581 & E704 collaborations Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.
Phys.Lett.B 276 (1992) 531-535, 1992.
Inspire Record 314231 DOI 10.17182/hepdata.29252

A measurement of the single-spin asymmetry A N in p↑ + p→ π 0 + X at 200 GeV with x F = 0 shows a transition in the production process from a “ low -x T ” regime with A N = 0, through an intermediate region of negative asymmetry, to a “ high -x T ” regime with A N > 0.3. This transition occurs at x T ≈ 0.4 and is consistent with x T -scaling of A N in pion production using polarized beams or targets from √− s =5.2 to 19.4 GeV. Results for A N in η production by polarized protons and in π 0 production by polarized antiprotons are also presented.

3 data tables

Statistical errors only.

Statistical errors only.

Statistical errors only.


Comparison of Spin Asymmetries and Cross Sections in $\pi^0$ Production by 200 GeV Polarized Antiprotons and Protons

The E581 & E704 collaborations Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.
Phys.Lett.B 261 (1991) 201-206, 1991.
Inspire Record 314232 DOI 10.17182/hepdata.29396

None

4 data tables

No description provided.

P P data are taken from Adams et al, Fermilab-Pub-91/13-E.

Ratio of the spin averaged invariant cross section for PI0 production in p p and pbar p interactions.

More…

Large $\chi_F$ Spin Asymmetry in $\pi^0$ Production by 200 GeV Polarized Protons

The E581 & E704 collaborations Adams, D.L. ; Akchurin, N. ; Belikov, N.I. ; et al.
Z.Phys.C 56 (1992) 181-184, 1992.
Inspire Record 314230 DOI 10.17182/hepdata.14557

The spin asymmetryAN for inclusive π0 production by 200-GeV transversely-polarized protons on a liquid hydrogen target has been measured at Fermilab over a wide range ofxF, with 0.5<pT<2 GeV/c. AtxF>0.3, the asymmetry rises with increasingxF and reaches a value ofAN=0.15±0.03 in the region 0.6<xF<0.8. This result provides new input regarding the question of the internal spin structure of transversely-polarized protons.

5 data tables

No description provided.

False asymmetry calculated for events with average beam polarization of zero.

No description provided.

More…