Weygand, D.P.
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Search for $D^*$- Production With a 16-{GeV}/$c \pi^-$ Beam

Chung, S.U. ; Etkin, A. ; Fernow, Richard C. ; et al.
Phys.Rev.Lett. 48 (1982) 785, 1982.
Inspire Record 170568 DOI 10.17182/hepdata.20594

A search for production of D*−'s using the decay chain D0π−, D0→K+π−, was carried out at the Brookhaven National Laboratory multiparticle spectrometer with a 16-GeV/c π− beam and a hydrogen target. At 95% confidence level the upper limits for the product of peripheral production cross section by branching ratio are 2.4 nb for inclusive D*− production and 1.3 nb for the exclusive channel π−p→D*−Λc.

1 data table match query
Table 1

UPPER LIMIT TO CROSS SECTIONS.


Near-threshold Photoproduction of Phi Mesons from Deuterium

Qian, X. ; Chen, W. ; Gao, H. ; et al.
Phys.Lett.B 696 (2011) 338-342, 2011.
Inspire Record 875788 DOI 10.17182/hepdata.56870

We report the first measurement of the differential cross section on $\phi$-meson photoproduction from deuterium near the production threshold for a proton using the CLAS detector and a tagged-photon beam in Hall B at Jefferson Lab. The measurement was carried out by a triple coincidence detection of a proton, $K^+$ and $K^-$ near the theoretical production threshold of 1.57 GeV. The extracted differential cross sections $\frac{d\sigma}{dt}$ for the initial photon energy from 1.65-1.75 GeV are consistent with predictions based on a quasifree mechanism. This experiment establishes a baseline for a future experimental search for an exotic $\phi$-N bound state from heavier nuclear targets utilizing subthreshold/near-threshold production of $\phi$ mesons.

1 data table match query
Table 1

Differential cross section as a function of ABS(T-TMIN).


EXISTENCE OF XI RESONANCES ABOVE 2-GEV

Jenkins, Charles M. ; Albright, John R. ; Diamond, R.N. ; et al.
Phys.Rev.Lett. 51 (1983) 951-954, 1983.
Inspire Record 195471 DOI 10.17182/hepdata.20475

Ξ*− production was studied in the reaction K−+p→K+slow+X− at 5 GeV/c. The slow K+ was electronically detected, while the X− was observed as a missing mass, thus allowing for observation of all Ξ* independent of decay mode. The observed Ξ states were Ξ(1320), Ξ(1530), Ξ(1820), Ξ(2030), Ξ(2250), Ξ(2370), and Ξ(2500). These data establish and confirm the existence of Ξ(2250) and indicate a peculiar production-cross-section behavior for the Ξ*(2370).

1 data table match query
Table 1

UPPER LIMITS ARE 95 PCT CL.


Neutral Strange Particle Production in anti-Proton-Proton Reactions at 3.0-GeV/c

Jacobs, S.M. ; Kirsch, L.E. ; Moore, S.C. ; et al.
Phys.Rev.D 17 (1978) 1187, 1978.
Inspire Record 5857 DOI 10.17182/hepdata.24452

The reactions p¯p→V0+neutrals were studied in a multiparticle spectrometer at 3.0 GeV/c incident momentum, with a sensitivity of about 150 events/μb. Differential cross sections and polarization of the Λ¯ for the final states Λ¯(Λ) and Λ¯(Σ0) are reported and compared with theoretical models. Differential cross sections of the K0 in K0[K*(890)] and the Λ in Λ(Λ¯+Σ¯0) are also measured. Upper limits of a few μb MeV are obtained for the formation of narrow resonances decaying into V0+neutrals in the mass interval 2.74-2.80 GeV/c2.

5 data tables match query
Table 1

FORWARD HEMISPHERE TOTAL CROSS SECTIONS NOT INCLUDING CHARGE CONJUGATE REACTIONS. CORRECTED FOR DECAY BRANCHING RATIOS AND FOR BACKGROUNDS.

Table 2

No description provided.

Table 3

No description provided.

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Differential cross section and recoil polarization measurements for the gamma p to K+ Lambda reaction using CLAS at Jefferson Lab

The CLAS collaboration McCracken, M.E. ; Bellis, M. ; Meyer, C.A. ; et al.
Phys.Rev.C 81 (2010) 025201, 2010.
Inspire Record 840934 DOI 10.17182/hepdata.54967

We present measurements of the differential cross section and Lambda recoil polarization for the gamma p to K+ Lambda reaction made using the CLAS detector at Jefferson Lab. These measurements cover the center-of-mass energy range from 1.62 to 2.84 GeV and a wide range of center-of-mass K+ production angles. Independent analyses were performed using the K+ p pi- and K+ p (missing pi -) final-state topologies/ results from these analyses were found to exhibit good agreement. These differential cross section measurements show excellent agreement with previous CLAS and LEPS results and offer increased precision and a 300 MeV increase in energy coverage. The recoil polarization data agree well with previous results and offer a large increase in precision and a 500 MeV extension in energy range. The increased center-of-mass energy range that these data represent will allow for independent study of non-resonant K+ Lambda photoproduction mechanisms at all production angles.

241 data tables match query
Table 1

Differential cross section as a function of COS(THETA(K)) for the centre-of-mass range 1.62-1.63 GeV.

Table 2

Differential cross section as a function of COS(THETA(K)) for the centre-of-mass range 1.63-1.64 GeV.

Table 3

Differential cross section as a function of COS(THETA(K)) for the centre-of-mass range 1.64-1.65 GeV.

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Exclusive photoproduction of the Cascade (Xi) hyperons.

The CLAS collaboration Price, J.W. ; Nefkens, B.M.K. ; Ducote, J.L. ; et al.
Phys.Rev.C 71 (2005) 058201, 2005.
Inspire Record 660705 DOI 10.17182/hepdata.25222

We report on the first measurement of exclusive Xi-(1321) hyperon photoproduction in gamma p --> K+ K+ Xi- for 3.2 < E(gamma) < 3.9 GeV. The final state is identified by the missing mass in p(gamma,K+ K+)X measured with the CLAS detector at Jefferson Laboratory. We have detected a significant number of the ground-state Xi-(1321)1/2+, and have estimated the total cross section for its production. We have also observed the first excited state Xi-(1530)3/2+. Photoproduction provides a copious source of Xi's. We discuss the possibilities of a search for the recently proposed Xi5-- and Xi5+ pentaquarks.

1 data table match query
Table 1

Cross section averaged over the energy range 3.2 to 3.9 GeV.


Exclusive electroproduction of Phi mesons at 4.2-GeV.

The CLAS collaboration Lukashin, K. ; Smith, E.S. ; Adams, G.S. ; et al.
Phys.Rev.C 64 (2001) 059901, 2001.
Inspire Record 552246 DOI 10.17182/hepdata.38589

We studied the exclusive reaction e p --> e' p' phi using the phi --> K^+ K^- decay mode. The data were collected using a 4.2 GeV incident electron beam and the CLAS detector at Jefferson Lab. Our experiment covers the range in Q^2 from 0.7 to 2.2 GeV^2, and W from 2.0 to 2.6 GeV. Taken together with all previous data, we find a consistent picture of phi production on the proton. Our measurement shows the expected decrease of the t-slope with the vector meson formation time c Delta tau below 2 fm. At = 0.6 fm, we measure b_phi = 2.27 +- 0.42 GeV^-2. The cross section dependence on W as W^{0.2+-0.1} at Q^2 = 1.3 GeV^2 was determined by comparison with phi production at HERA after correcting for threshold effects. This is the same dependence as observed in photoproduction.

3 data tables match query
Table 1

Slope of the DSIG/DT distribution in different Q**2 regions.

Table 2

Cross section as a function of Q**2 and W.

Table 3

The differential cross section for exclusive PHI electroproduction off the photon, (TP=T-TMIN).


Eta photoproduction on the proton for photon energies from 0.75-GeV to 1.95-GeV

The CLAS collaboration Dugger, M. ; Ritchie, B.G. ; Ball, J. ; et al.
Phys.Rev.Lett. 89 (2002) 222002, 2002.
Inspire Record 603904 DOI 10.17182/hepdata.19406

Differential cross sections for γp→ηp have been measured with tagged real photons for incident photon energies from 0.75 to 1.95 GeV. Mesons were identified by missing mass reconstruction using kinematical information for protons scattered in the production process. The data provide the first extensive angular distribution measurements for the process above W=1.75  GeV. Comparison with preliminary results from a constituent quark model support the suggestion that a third S11 resonance with mass ∼1.8  GeV couples to the ηN channel.

6 data tables match query
Table 1

Cross sections for photon energies 0.775 to 0.925 GeV.

Table 2

Cross sections for photon energies 0.975 to 1.125 GeV.

Table 3

Cross sections for photon energies 1.175 to 1.325 GeV.

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eta' photoproduction on the proton for photon energies from 1.527-GeV to 2.227-GeV.

The CLAS collaboration Dugger, M. ; Ball, J.P. ; Collins, P. ; et al.
Phys.Rev.Lett. 96 (2006) 062001, 2006.
Inspire Record 700399 DOI 10.17182/hepdata.31553

Differential cross sections for the reaction gamma p -> eta-prime p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data indicate for the first time the coupling of the etaprime N channel to both the S_11(1535) and P_11(1710) resonances, known to couple strongly to the eta N channel in photoproduction on the proton, and the importance of j=3/2 resonances in the process.

5 data tables match query
Table 1

Differential cross sections for ETAPRIME photoproduction on the proton at photon energies 1.527, 1.577 and 1.627 GeV. The errors shown are combined statistical and systematic.

Table 2

Differential cross sections for ETAPRIME photoproduction on the proton at photon energies 1.677, 1.728 and 1.779 GeV. The errors shown are combined statistical and systematic.

Table 3

Differential cross sections for ETAPRIME photoproduction on the proton at photon energies 1.829, 1.879 and 1.930 GeV. The errors shown are combined statistical and systematic.

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Measurement of the polarized structure function sigma(LT') for pion electroproduction in the Roper resonance region.

The CLAS collaboration Joo, K. ; Smith, L.C. ; Aznauryan, I.G. ; et al.
Phys.Rev.C 72 (2005) 058202, 2005.
Inspire Record 681275 DOI 10.17182/hepdata.25214

The polarized longitudinal-transverse structure function $\sigma_{LT^\prime}$ measures the interference between real and imaginary amplitudes in pion electroproduction and can be used to probe the coupling between resonant and non-resonant processes. We report new measurements of $\sigma_{LT^\prime}$ in the $N(1440){1/2}^+$ (Roper) resonance region at $Q^2=0.40$ and 0.65 GeV$^2$ for both the $\pi^0 p$ and $\pi^+ n$ channels. The experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at a beam energy of 1.515 GeV. Complete angular distributions were obtained and are compared to recent phenomenological models. The $\sigma_{LT^\prime}(\pi^+ n)$ channel shows a large sensitivity to the Roper resonance multipoles $M_{1-}$ and $S_{1-}$ and provides new constraints on models of resonance formation.

58 data tables match query
Table 1

Polarized structure function of the reaction E- P --> E- PI0 P for Q**2 = 0.40 and W = 1.1 GeV.

Table 2

Polarized structure function of the reaction E- P --> E- PI0 P for Q**2 = 0.40 and W = 1.14 GeV.

Table 3

Polarized structure function of the reaction E- P --> E- PI0 P for Q**2 = 0.40 and W = 1.18 GeV.

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