Holmgren, S.-O.
DSIG/DU
Max results
Sort by Reverse order

Showing 10 of 31 results

Date

Measurement of Differential Cross-Section and Polarization in the Backward Peak of the Reactions pi- p --> Lambda K0 and pi- p --> Lambda K* (890) at 8-GeV/c

Brundiers, H. ; Hartung, R. ; Runge, K. ; et al.
Nucl.Phys.B 119 (1977) 349-361, 1977.
Inspire Record 123952 DOI 10.17182/hepdata.35527

Differential cross sections and polarizations have been measured for the backward peaks in the reactions π − p →Λ K 0 and π − p →Λ K ∗ (890) at 8 GeV/c. The experiment was performed with a liquid hydrogen target at the ω spectrometer. The cross sections for u′>−2 ( GeV /c) 2 are 0.27 ± 0.03 μ b for π − p →Λ+ K 0 and 0.55±0.07 μ b for π − p →Λ K ∗0 . Large positive Λ polarization was observed in both reactions for u ′>−0.5 (GeV/ c ) 2 . The dominant production mechanism was found to be unnatural baryon exchange.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////).

Table 3

No description provided.


The Reactions K- p --> pi-+ Sigma+- at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Massaro, G.G.G. ; Barlag, S. ; de Groot, A.J. ; et al.
Phys.Lett.B 66 (1977) 385-389, 1977.
Inspire Record 110532 DOI 10.17182/hepdata.27595

We present differential cross sections and the Σ + polarization for the reactions K − p → π ∓ Σ ± using data from a high statistics bubble chamber experiment at 4.2 GeV/ c incident momentum. The statistical level allows a detailed analysis of these reactions over the whole t range. Several significant structures are observed. Comparisons are made with SU(3)-related reactions; for backward production of π − Σ + such a comparison shows good evidence for Δ exchange. The exotic forward peak in K − p → π + Σ − is definitely confirmed.

7 data tables
Table 1

Axis error includes +- 5/5 contribution.

Table 2

Axis error includes +- 5/5 contribution.

Table 3

Axis error includes +- 5/5 contribution.

More…

A Study of the Final States anti-K0 n, Lambda pi0 and anti-K0 Delta0 in K- p Interactions at 5-GeV/c and 8-GeV/c

Gallivan, J. ; Astbury, P. ; Jafar, J. ; et al.
Nucl.Phys.B 117 (1976) 269-292, 1976.
Inspire Record 110114 DOI 10.17182/hepdata.35539

We present results on three reactions involving neutral final states which were studied in a magnet spark chamber system. These results are: (a) differential cross section with high statistics for K − p → K 0 n at 5 GeV /c (24 000 events) and at 8 GeV/ c (11 000 events) for t′ <2.0 (GeV/ c ) 2 ; (b) differential cross section and polarization for K − p → Λπ 0 (backward peak) at 5 GeV/ c for u ′ < 1.4 GeV/ c ) 2 ; and (c) differential cross section for K − p → K 0 Δ 0 (1232) at 5 GeV /c for t′ < 1.2 ( GeV /c) 2 . We compare our results with existing data and draw some phenomenological conclusions.

7 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////TP INDEPENDENT CORRECTIONS AT 5 AND 8 GEV ARE 5.143 +- 0.418 AND 4.981 +- 0.436 RESPECTIVELY).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////TP INDEPENDENT CORRECTIONS AT 5 AND 8 GEV ARE 5.143 +- 0.418 AND 4.981 +- 0.436 RESPECTIVELY).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////UP INDEPENDENT CORRECTION FACTOR IS 3.840 +- 0.323).

More…

The Reactions K- p --> pi-+ Sigma+- (1385) at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Holmgren, S.O. ; Aguilar-Benitez, M. ; Barreiro, F. ; et al.
Nucl.Phys.B 119 (1977) 261-291, 1977.
Inspire Record 110408 DOI 10.17182/hepdata.35566

The reactions K − p→ π − Σ + (1385) and K − p→ π + Σ − (1385) are studied at 4.2 GeV c incident momentum using data from a high statistics bubble chamber experiment corresponding to ∼80 events/μb. The total and differential cross sections are presented. Amplitude analyses are performed and the complete Σ ± (1385) helicity spin density matrices are extracted. The results are compared with the predictions of the additive quark model and exchange degeneracy. A substantial cross section is observed for the reaction K − p→ π + Σ − (1385) in the forward direction, which implies exotic meson quantum numbers in the t -channel. One possible interpretation of this process provides an explanation for the small but significant violations of the additive quark model predictions observed in the reaction K − p→ π − Σ + (1385) at low four-momentum transfer. In the backward direction unnatural parity exchange is shown to give a larger contribution to K − p→ Σ − (1385) π + than natural parity exchange.

11 data tables
Table 1

Axis error includes +- 5/5 contribution.

Table 2

Axis error includes +- 5/5 contribution.

Table 3

Axis error includes +- 5/5 contribution.

More…

Elastic Backward Scattering of Negative Pions on Protons at 25-GeV/c and 38-GeV/c

Babaev, A. ; Brakhman, E. ; Danilov, M. ; et al.
Phys.Lett.B 67 (1977) 351, 1977.
Inspire Record 109000 DOI 10.17182/hepdata.39798

The backward elastic scattering reaction π − p → p π − at momenta 25 and 38 GeV/ c have been measured using a magnetic spectrometer with hybrid chambers. The experimental data on the dependence of the cross section d σ /d u on the momentum transfer u as well as the energy dependence d σ /d u at u = 0 are given.

2 data tables

Measurement of the Reactions K- p --> Sigma+ pi- and pi- p --> p pi- Near the Backward Direction at 3.0-GeV/c and 5.1-GeV/c

Hoffman, E.W. ; Dixon, Roger L. ; Fletcher, J.M. ; et al.
Phys.Rev.Lett. 35 (1975) 138-141, 1975.
Inspire Record 2233 DOI 10.17182/hepdata.21176

We have measured differential cross sections for K−p→Σ+π− and π−p→pπ− at 3.0 and 5.1 GeV/c near the backward direction. At 3.0 GeV/c both have a dip near −u∼0.1 (GeV/c)2. At 5.1 GeV/c, dσdu for π−p→pπ− falls exponentially with slope 3.8±0.1 (GeV/c)−2 whereas dudσ for K−p→Σ+π− exhibits a decreasing slope for larger |u|. These data are discussed in terms of SU(3), and the relative importance of the helicity-flip and -non-flip amplitudes is investigated.

1 data table
Table 1

No description provided.


Measurement of the Differential Cross-Section and the Spin-Correlation Parameters P,A, and R in the Backward Peak of pi- p --> K0 Lambda at 5-GeV/c

Astbury, P. ; Gallivan, J. ; Jafar, J. ; et al.
Nucl.Phys.B 99 (1975) 30-52, 1975.
Inspire Record 98667 DOI 10.17182/hepdata.31861

We present measurements for the baryon-exchange reaction π − p→ Λ K 0 at 5 GeV/ c over the range − u <2(GeV/ c ) 2 . The differential cross section is obtained from events produced on a liquid hydrogen target. These data are combined with events produced on a butanol polarized target and the parameters P , A , and R are then determined from an analysis of the decay angular distribution of the forward-going Λ. From our data it is possible to determine the magnitudes and the relative phase of the two invariant amplitudes A ′ and B . The consequences for the ratio B / A ′ are discussed in detail.

4 data tables
Table 1

No description provided.

Table 2

THE ERRORS QUOTED IN D(SIG)/DU DO NOT INCLUDE THE ERROR ASSIGNED TO THE OVERALL U-INDEPENDENT CORRECTIONS FACTOR (4.62 +- 0.36), OR OTHER POSSIBLE NORMALIZATION ERRORS.

Table 3

No description provided.

More…

Study of Hypercharge Exchange Reactions of the Type K- p --> 1- 3/2+- at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Aguilar-Benitez, M. ; Barreiro, F. ; Hemingway, R.J. ; et al.
Nucl.Phys.B 124 (1977) 189-228, 1977.
Inspire Record 101289 DOI 10.17182/hepdata.50024

Results are presented for the quasi two-body hypercharge exchange reactions of the type using data from a high statistics bubble chamber experiment. Total and differential cross sections and the momentum transfer dependence of the meson and hyperon resonance single density matrix elements are discussed. Amplitude analyses are performed for the first two reactions. The results are compared with quark model and duality predictions and with those from other related reactions.

20 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Measurement of the Backward Peaks in the Reactions pi- p --> K0 Lambda and pi- p --> K*0 (890) Lambda

Foley, K.J. ; Love, W.A. ; Ozaki, S. ; et al.
Phys.Rev.D 10 (1974) 2763, 1974.
Inspire Record 1420 DOI 10.17182/hepdata.24944

We present the differential cross sections near u=0 for the reactions π−p→K0Λ and π−p→K*0(890)Λ at incident pion momenta of 8 and 10.7 GeV/c. The differential cross section for the first reaction follows the exponential dependence on u previously observed, while the second shows a dip in the backward direction.

3 data tables
Table 1

Axis error includes +- 25/25 contribution.

Table 2

Axis error includes +- 25/25 contribution.

Table 3

Axis error includes +- 25/25 contribution.


Backward production of rho0 and f0 mesons in pi+ n interactions at 6 gev/c

Dado, S. ; Engler, A. ; Kraemer, R.W. ; et al.
Phys.Lett.B 50 (1974) 275-279, 1974.
Inspire Record 95262 DOI 10.17182/hepdata.27950

Backward production of ϱ 0 and f 0 mesons in π + n interactions at 6 GeV/ c is presented. Total and differential cross sections are reported along with spin density matrix elements.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

JACKSON (U) FRAME (Z=2).

More…