Allen, D.D.
Pion-Proton Scattering
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Negative pion-proton elastic scattering at 1.7 GeV/c

Allen, D.D. ; Fisher, G.P. ; Godden, G. ; et al.
Phys.Lett. 21 (1966) 468-470, 1966.
Inspire Record 1385170 DOI 10.17182/hepdata.29931

The differential elastic scattering cross section for 1.7 GeV/c pion- on protons is evaluated by analysis of Brookhaven 20" bubble chamber film. Primary and secondary diffraction peaks are evident. These are discussed in terms of optical model parameters.

1 data table
Table 1

No description provided.


Measurement of pi- p ---> pi0 n in the vicinity of the eta threshold

Starostin, A. ; Prakhov, S. ; Nefkens, B.M.K. ; et al.
Phys.Rev.C 72 (2005) 015205, 2005.
Inspire Record 688197 DOI 10.17182/hepdata.25171

We report a new measurement of the differential cross section for π−p→π0n from pπ=649 to 752 MeV/c, which is around the opening of the η channel (685 MeV/c). Our data support the main features of the π−p charge-exchange differential cross sections generated by the SAID πN partial-wave analysis. The opening of the η channel has a clear effect on the shape of the excitation function for dσ(π−p→π0n), which is most noticeable in the backward direction.

9 data tables
Table 1

Differential cross section for incident pion momentum 649, 654 and 657 MeV.

Table 2

Differential cross section for incident pion momentum 661, 666 and 669 MeV.

Table 3

Differential cross section for incident pion momentum 673, 678 and 681 MeV.

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Differential cross section of the pion nucleon charge-exchange reaction pi- p --> pi0 n in the momentum range from 148-MeV/c to 323-MeV/c.

The Crystal Ball collaboration Sadler, M.E. ; Kulbardis, A. ; Abaev, V. ; et al.
Phys.Rev.C 69 (2004) 055206, 2004.
Inspire Record 646714 DOI 10.17182/hepdata.31725

Measured values of the differential cross section for pion-nucleon charge exchange are presented at momenta 148, 174, 188, 212, 238, 271, 298, and 323 MeV/c, a region dominated by the Delta resonance. Complete angular distributions were obtained using the Crystal Ball detector at the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL). Statistical uncertainties of the differential cross sections are typically 2-6%, exceptions being the results at the lowest momentum and at the most forward measurements of the five lowest momenta. We estimate the systematic uncertainties to be 3-6%.

3 data tables
Table 1

The errors shown are statistical only.

Table 2

The errors shown are statistical only.

Table 3

The total charge-exchange reaction cross section as a function of pion momentum obtained by integrating the differential cross sections. The errors shown are the total and statistical errors.


Measurement of the pi- p ---> 3 pi0 n total cross section from threshold to 0.75 GeV/c

Starostin, A. ; Nefkens, B.M.K. ; Manley, D.M. ; et al.
Phys.Rev.C 67 (2003) 068201, 2003.
Inspire Record 620818 DOI 10.17182/hepdata.25279

We report a new measurement of the π−p→3π0n total cross section from threshold to pπ=0.75GeV/c. The cross section near the N(1535)12− resonance is only a few μb after subtracting the large η→3π0 background associated with π−p→ηn. A simple analysis of our data results in the estimated branching fraction B[S11→πN(1440)12+]=(8±2)%. This is the first such estimate obtained with a three-pion production reaction.

1 data table
Table 1

Total cross section from threshold to 750 MeV. Only statistical errors are given in the table.


Study of the reactions pi+ p ---> k+ sigma+ and pi+ p ---> k+ y*+(1385) between 3.5 and 14 gev/c

Bashian, A. ; Finocchiaro, G. ; Good, M.L. ; et al.
Phys.Rev.D 4 (1971) 2667-2679, 1971.
Inspire Record 74763 DOI 10.17182/hepdata.23097

Measurements of the differential cross section for the reactions π+p→K+Σ+ and π+p→K+Y*+(1385) are reported at 3.5, 3.75, 4.0, 4.25, 4.5, 4.75, 5.0, 6.0, 10.0, and 14.0 GeV/c. Polarization in π+p→K+Σ+ is also reported at 6.0, 10.0, and 14.0 GeV/c. At small |t|, the cross section for π+p→K+Σ+ is well described by an exponential Aebt with slopes in the range b≈8−10 (GeV/c)−2; for |t|>0.5 (GeV/c)2 this slope decreases considerably. The cross section for π+p→K+Y*+(1385) is well described for |t|>0.2 (GeV/c)2 by a single exponential of slope about half that for π+p→K+Σ+; there is no break near |t|>0.5 (GeV/c)2. We observe a dip in this cross section near t=0. The polarization in π+p→K+Σ+ is consistent with zero for |t|<0.4 (GeV/c)2 and becomes large and positive for larger |t|.

22 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Pi+- p elastic scattering and pi+ p ---> k+ sigma+ at 5.0 gev/c near -t=3.0(gev/c)-squared

Akerlof, C.W. ; Caldwell, P.K. ; Kalbaci, P. ; et al.
Phys.Rev.Lett. 27 (1971) 219-222, 1971.
Inspire Record 68949 DOI 10.17182/hepdata.21476

We have measured the reactions π±p→π±p and π+p→K+Σ+ at 5.0 GeV/c in the region 2.2<−t<3.5 (GeV/c)2. We find the minimum cross section of the dip at −t=2.8 (GeV/c)2 in π+p elastic scattering to be 0.16 ± 0.05 μb/GeV2. The π−p differential cross section exhibits similar structure, while the π+p→K+Σ+ channel shows a steady decline in cross section as |t| increases. The polarization of the Σ+ remains large and positive to at least −t=2.8 (GeV/c)2.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Search for peripheral k+ production in pi- p interactions from 2.75 to 10 gev/c

Bashian, A. ; Finocchiaro, G. ; Good, M.L. ; et al.
Phys.Rev.D 4 (1971) 2680-2683, 1971.
Inspire Record 74755 DOI 10.17182/hepdata.23181

Upper limits are presented for the differential cross section in the reactions π−p→K+Σ− and π−p→K+Y*−(1385) with small momentum transfer from π− to K+.

2 data tables
Table 1

EXTRAPOLATED TO T=0 ASSUMING SLOPE IS 5 GEV**-2.

Table 2

ISOTROPIC ANGULAR DISTRIBUTION ASSUMED IN GIVEN T-RANGE.


Differential cross-sections in pi- p ---> k0 lambda0 and pi- p ---> k0 sigma0 from 3 to 6 gev/c

Ward, C.E.W. ; Ambats, I. ; Lesnik, A. ; et al.
Phys.Rev.Lett. 31 (1973) 1149-1152, 1973.
Inspire Record 83757 DOI 10.17182/hepdata.21372

We have measured the differential cross sections for the associated-production reactions π−p→K0Λ0 and π−p→K0Σ0 at 3, 4, 5, and 6 GeV/c, with a total of over 40 000 events. We find that both reactions have exponential forward peaks for −t≲0.4 (GeV/c)2, with no indication of forward-direction flattening or turnover; the slopes of the forward peaks show little if any variation with momentum; and the two cross sections are equal within experimental error from −t=1.2 (GeV/c)2 out to at least −t=2.0 (GeV/c)2.

5 data tables
Table 1

INTERCEPT AND SLOPE FROM FIT TO D(SIG)/DT (PRESUMABLY FOR -TP < ABOUT 0.4 GEV**2).

Table 2

No description provided.

Table 3

No description provided.

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A MEASUREMENT OF POLARIZATION IN pi- p ---> K0 LAMBDA0 AT 5-GeV/c

Ward, C.E.W. ; Ambats, I. ; Lesnik, A. ; et al.
Phys.Lett.B 48 (1974) 471-473, 1974.
Inspire Record 80559 DOI 10.17182/hepdata.27997

We have measured the Λ° polarization in π − p→ K°Λ° at 5 GeV / c , using a data sample of 3709 events. The polarization is positive for small t , passes through zero near t = −0.3 (GeV/ c ) 2 , and becomes large and negative at larger t , consistent with a value of −1.0 for t between −0.7 and −1.6(GeV/ c ) 2 .

1 data table
Table 1

THE AUTHORS FEEL THAT THE POLARIZATIONS > 1 IN ABSOLUTE VALUE ARE PROBABLY DUE TO STATISTICS RATHER THAN SYSTEMATIC ERRORS.


Differential cross-section for backward pi+ p scattering from 3.25 to 10 gev/c

Bashian, A. ; Finocchiaro, G. ; Good, M.L. ; et al.
Phys.Rev.D 9 (1974) 3193-3196, 1974.
Inspire Record 94286 DOI 10.17182/hepdata.21973

We present differential cross-section data for the reaction π+p→π+p near 180° in the center-of-mass system at beam momenta between 3.25 GeVc and 10 GeVc.

2 data tables
Table 1

No description provided.

Table 2

No description provided.