Partial Wave Analysis of the Q Region in the Reactions K- p --> K- pi+ pi- p and K- p --> anti-K0 pi- pi0 p at 14.3-GeV/c

Tovey, S.N. ; Hansen, J.D. ; Paler, K. ; et al.
Nucl.Phys.B 95 (1975) 109-129, 1975.
Inspire Record 2363 DOI 10.17182/hepdata.31975

We have studied the reactions K − p → K − π + π − p and K − p → K 0 π − π 0 p at 14.3 GeV/ c using respectively 15 992 and 3723 events. Partial-wave analysis of the region 1.0 < m (K ππ ) < 1.7 GeV have been made using a modified version of the method developed at the University of Illinois.

1 data table match query

No description provided.


Evidence for Different Polarization Properties of the rho K and K* (890) pi States of the 1+ Wave in the Q Region

The Aachen-Berlin-CERN-London-Vienna collaboration Otter, G. ; Rudolph, G. ; Rumph, K. ; et al.
Nucl.Phys.B 93 (1975) 365-386, 1975.
Inspire Record 99251 DOI 10.17182/hepdata.32005

A partial-wave analysis has been performed on the (K − π − π + ) system produced in the reaction K − p → K − π − π + p at 10 and 16 GeV/ c . In the Q mass region it is found that the two dominant states, K ∗ π and Kπ, both in 1 + S wave, are produced with different polarisations, helicity being approximately conserved in the t -channel for K ∗ π and in the s -channel for Kπ. This is in contradiction with the assumption that the amplitude can be factorised into “production” and “decay” parts, and hence that the two amplitudes are fully coherent. The phase variation of the two states do not indicate simple resonance behaviour. It is concluded that the Q-mass enhancement is composite.

1 data table match query

No description provided.


A Comparison of pi pi pi, anti-K pi pi, pi K anti-K, anti-K K anti-K Systems Produced in the Reactions Meson + p --> 3 Mesons + p

The Aachen-Berlin-Bonn-CERN-Heidelberg-London-Vienna collaboration Bosetti, P. ; Otter, G. ; Rudolph, G. ; et al.
Nucl.Phys.B 101 (1975) 304-332, 1975.
Inspire Record 100226 DOI 10.17182/hepdata.36082

A comparison is made of the low-mass three-meson systems (πππ), (Kππ), (π K K ) and ( K K K ) diffractively produced in the reaction meson + proton → three mesons + proton. Several striking similarities and a few important differences are observed: (i) the reactions are consistent with the assumption that the three mesons decay entirely into a 0 − meson and a 0 + , 1 − or 2 + resonance; (ii) the three-meson mass spectra have a peak ≈ 250 MeV above the effective threshold M eff of the dominant decay mode and then fall off approximately as (mass) −3 ;(iii) the average spin 〈 J 〉 = 0.55 + 1.1 Q eff , where Q eff = M - M eff ; (iv) the average orbital angular momentum 〈 l 〉 increases according to 〈 l 〉 = 0.75 Q eff ; (v) the three-meson states are produced dominantly in unnatural spin-parity states and no evidence for their being resonant is found; (vi) the only natural spin-parity states found are the well-established 2 + resonances A 2 and K ∗ (1420); they have similar properties to the non-resonant unnatural parity states except for a dip at t = 0 in the dσ/d t distributions; (vii) both the unnatural and natural spin-parity states are produced mostly by an exchange of natural parity; (viii) there is evidence for two types of production mechanism with different polarization properties, one approximately conserving helicity in the t -channel and the other in the s -channel.

1 data table match query

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Observation of a Dip at /T/ = 1.5-({GeV}/$c$)**2 in $\bar{p} p$ Elastic Scattering at 50-{GeV}/$c$

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Asad, Z. ; Baglin, C. ; Benso, S. ; et al.
Phys.Lett.B 108 (1982) 51, 1982.
Inspire Record 164883 DOI 10.17182/hepdata.31019

The p p elastic differential cross section at 50 GeV/c has been measured in a two-arm spectrometer experiment at the CERN SPS. The | t | range covered extends from 0.7 to 5 (GeV/c. A pronounced dip-bump structure is observed with a sharp minimum at | t | = 1.5 (GeV/ c ) 2 .

1 data table match query

No description provided.


Evidence for Structure in the 1+ State of the Q Region

The Aachen-Berlin-CERN-London-Vienna & Ecole Poly-Rutherford-Saclay collaborations Otter, G. ; Rudolph, G. ; Schmid, P. ; et al.
Nucl.Phys.B 106 (1976) 77-94, 1976.
Inspire Record 3373 DOI 10.17182/hepdata.35803

We have performed a partial-wave analysis of the mainly diffractively produced low-mass (K ππ ) system in the reactions K − p → K − π + π − p and K − p → K 0 π − π 0 p at 10, 14 and 16 GeV /c . We find that the dominant 1 + S ( K ∗ π ) state has possibly a two-peak structure (around 1.27 and 1.37 GeV). In contrast the 1 + S(K ϱ ) state shows one narrow peak near thershold (around 1.27 GeV). These states are found to be of different origin. The results favour the interpretation of the 1 + S(K ϱ ) as a 1 + resonance below the (K ϱ ) threshold. The t ′ pp dependence is found to be different for the 1 + and 0 − states.

1 data table match query

No description provided.


Large Angle Elastic Scattering of Charged Pions on Protons at 20-{GeV}/c and 30-{GeV}/c Incident Momenta

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Almas, R. ; Baglin, C. ; Bock, R. ; et al.
Phys.Lett.B 93 (1980) 199-202, 1980.
Inspire Record 152838 DOI 10.17182/hepdata.27195

Elastic cross-section measurements are presented for π ± −p at 20 GeV/ c and π − −p at 30 GeV/ c incident momenta in the large angle region (50° to 90° in the c.m. system). The data are compared with published lower energy elastic cross sections. A test is made of the dimensional counting rules for π ± −p elastic scattering and some indication of a deviation from this rule is observed in the π − −p case. A comparison is also made with the predictions of the constituent interchange model. Although the broad features of the predictions are confirmed, there are some important discrepancies. Finally, the predictions of the model due to Preparata and Soffer are also compared with the new data.

3 data tables match query

No description provided.

THE UPPER LIMIT QUOTED WHEN NO EVENTS OBSERVED IS THE CROSS SECTION CORRESPONDING TO ONE DETECTED EVENT.

THE UPPER LIMIT QUOTED WHEN NO EVENTS OBSERVED IS THE CROSS SECTION CORRESPONDING TO ONE DETECTED EVENT.


Pion - Proton Elastic Scattering at 20-{GeV}/$c$ and 50-{GeV}/$c$ Incident Momenta in the Momentum Transfer Range 0.7-{GeV}/$c < sqrt{t}< 8$-{GeV}/$c$

The Annecy(Lapp)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Asad, Z. ; Baglin, C. ; Benso, S. ; et al.
Phys.Lett.B 118 (1982) 442, 1982.
Inspire Record 179091 DOI 10.17182/hepdata.30852

Measurements of the differential elastic cross sections for π − p scattering at incident momenta of 20 and 50 GeV c and π + p at 50 GeV c in the momentum transfer range 0.7 < |t|; < 8.0 ( GeV c ) 2 are presented. The data are compared with various models of elastic scattering.

3 data tables match query

No description provided.

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An Experimental Study of Large Angle Elastic Scattering of Charged Mesons and Anti-protons on Protons at 20-{GeV}/$c$ and 30-{GeV}/$c$

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Baglin, C. ; Bock, R. ; Brobakken, K. ; et al.
Nucl.Phys.B 216 (1983) 1-39, 1983.
Inspire Record 180922 DOI 10.17182/hepdata.34020

A description is given of an experiment to study elastic scattering of π ± , K ± and p on protons at c.m. scattering angles from 45° to 100° at incident laboratory momenta 20 GeV/ c and 30 GeV/ c . The corresponding t range is from −6.2 (GeV/ c ) 2 to −28 (GeV/ c ) 2 . There are no previous observations for these reactions in this t range. High intensity and large geometrical acceptance were required in order to measure the low cross sections. The experiment used a double-arm spectrometer. MWPCs were used for reconstruction, and threshold and differential Čerenkov counters for identification. Scintillation counters, Čerenkov counters and a hadron calorimeter were used in the trigger. The trigger logic utilized specially designed matrices and a hard wired microprocessor. The π − p elastic scattering cross sections follow approximately the dimensional counting rule from 3.5 GeV/ c .and up to 30 GeV/ c . The cross sections decrease by seven orders of magnitude in this energy range. The data is compared to quark models. None of these models give a comprehensive description of the results. However, some modifications to these models improve their consistency with the data.

8 data tables match query

EARLIER RESULTS GIVEN IN 'A'.

No description provided.

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NEW RESULTS ON KAON - PROTON ELASTIC SCATTERING AT LARGE MOMENTUM TRANSFERS

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Asad, Z. ; Baglin, C. ; Bock, R. ; et al.
Phys.Lett.B 123 (1983) 265-268, 1983.
Inspire Record 182422 DOI 10.17182/hepdata.30730

Measurements of the K - p and K + p elastic differential cross sections at 20 and 50 GeV/ c , respectively, have been made in the momentum transfer range 0.7 < ∥ t ∥ < 8.0 GeV/ c .

2 data tables match query

No description provided.

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$K^\pm p$ Large Angle Elastic Scattering at 20-{GeV}/$c$ and 30-{GeV}/$c$

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Almas, R. ; Baglin, C. ; Bock, R. ; et al.
CERN-EP/80-79, 1980.
Inspire Record 153574 DOI 10.17182/hepdata.49655

None

3 data tables match query

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$K^- p$ elastic scattering at 10 GeV/c

The Aachen-Berlin-CERN-London (I.C.)-Vienna collaboration Aderholz, M. ; Bartsch, J. ; Keppel, E. ; et al.
Phys.Lett.B 24 (1967) 434-437, 1967.
Inspire Record 1392680 DOI 10.17182/hepdata.29583

K − p elastic scattering at 10 GeV/ c is studied on ∼3600 bubble chamber events. The elastic cross section is found to be σ el = (3.20 ± 0.14)mb and the ratio σ el σ tot = (0.142 ± 0.006) , that is below the upper limit of 0.185 suggested in a model by Van Hove. The value of the forward differential cross section is consistent with zero real part to the scattering amplitude. The slope of d σ d t is similar to that for π ± and greater than that of K + , with no evidence for shrinkage of the diffraction peak. No events of backward scattering were observed. The Regge-pole model of Phillips and Rarita gives a good fit to the data.

1 data table match query

No description provided.


Measurement of the real part of the k- p elastic scattering amplitude at 10 gev/c

Campbell, J.R. ; Cocconi, V.T. ; Duinker, P. ; et al.
Nucl.Phys.B 64 (1973) 1-13, 1973.
Inspire Record 94948 DOI 10.17182/hepdata.32421

Bubble chamber film of 10 GeV/ c K − p interactions was scanned automatically by an H.P.D. to look for small angle scatters in the | t |-range from 0.008 to 0.1 GeV 2 . Combining the 1800 events so obtained with 22 000 elastic events obtained from normal scanning (| t | > 0.06 GeV 2 ), the real part of the elastic scattering amplitude was found to be (+25 ± 10)% of the imaginary part. Evidence is found for a change in slope in the differential cross-section distribution, from 9.8 ± 0.6 GeV −2 in the | t |-range below 0.1 GeV 2 to 7.1 ± 0.2 GeV −2 in the range 0.12 < | t | ⩽ 0.4 GeV 2 .

4 data tables match query

No description provided.

THE 10 PCT ERROR IS THE RESULT OF A 5 PCT ERROR FROM THE FIT AND AN 8 PCT NORMALIZATION UNCERTAINTY.

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K- p elastic scattering at 10-GeV/c

The Aachen-Berlin-CERN-London-Vienna collaboration Bartsch, J. ; Deutschmann, M. ; Kraus, G. ; et al.
Nucl.Phys.B 29 (1971) 398-404, 1971.
Inspire Record 68635 DOI 10.17182/hepdata.33567

Results are presented on elastic scattering of 10.1 GeV/ c K − mesons on protons, based on a sample of 16 261 kinematically-fitted bubble-chamber events. The differential cross section is given over the | t |- range of 0.06 to 2.5 GeV 2 and is fitted with the expressions a e bt , A e Bt + Ct 2 and ( P e Qt + Re St ) over various intervals of t . The results are compared with those of other experiments at nearby energies. Upper limits of | α | < 0.28 and σ B < 0.4 μ b (both at a 90% confidence level) are given for the ratio of real to imaginary part of the forward-scattering amplitude and the backward-elastic-scattering cross section, respectively.

3 data tables match query

No description provided.

ERROR INCLUDES STATISTICAL ERROR AND ERROR IN TOTAL CROSS SECTION USED FOR NORMALIZATION. EXTRAPOLATION OF D(SIG)/DT TO T=0 PROVIDES ABOUT 0.5 PCT UNCERTAINTY.

NO BACKWARD EVENTS OBSERVED. LARGEST ANGLE EVENT SEEN WAS AT 64 DEG (-T = 2.33 GEV**2).


Coherent diffractive photoproduction of $\rho^{0}$ mesons on gold nuclei at RHIC

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.C 96 (2017) 054904, 2017.
Inspire Record 1515028 DOI 10.17182/hepdata.101354

The STAR Collaboration reports on the photoproduction of $\pi^+\pi^-$ pairs in gold-gold collisions at a center-of-mass energy of 200 GeV/nucleon-pair. These pion pairs are produced when a nearly-real photon emitted by one ion scatters from the other ion. We fit the $\pi^+\pi^-$ invariant mass spectrum with a combination of $\rho$ and $\omega$ resonances and a direct $\pi^+\pi^-$ continuum. This is the first observation of the $\omega$ in ultra-peripheral collisions, and the first measurement of $\rho-\omega$ interference at energies where photoproduction is dominated by Pomeron exchange. The $\omega$ amplitude is consistent with the measured $\gamma p\rightarrow \omega p$ cross section, a classical Glauber calculation and the $\omega\rightarrow\pi^+\pi^-$ branching ratio. The $\omega$ phase angle is similar to that observed at much lower energies, showing that the $\rho-\omega$ phase difference does not depend significantly on photon energy. The $\rho^0$ differential cross section $d\sigma/dt$ exhibits a clear diffraction pattern, compatible with scattering from a gold nucleus, with 2 minima visible. The positions of the diffractive minima agree better with the predictions of a quantum Glauber calculation that does not include nuclear shadowing than with a calculation that does include shadowing.

13 data tables match query

The $\pi^+\pi^-$ invariant-mass distribution for all selected $\pi\pi$ candidates with $p_T~<~100~\textrm{MeV}/c$.

The ratio $|B/A|$ of amplitudes of nonresonant $\pi^+\pi^-$ and $\rho^0$ mesons in the present STAR analysis.

The ratio $|B/A|$ of amplitudes of nonresonant $\pi^+\pi^-$ and $\rho^0$ mesons in the previous STAR analysis, Phys. Rev. C 77 034910 (2008).

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Measurement of the t distribution in diffractive photoproduction at HERA.

The ZEUS collaboration Breitweg, J. ; Derrick, M. ; Krakauer, D. ; et al.
Eur.Phys.J.C 2 (1998) 237-246, 1998.
Inspire Record 452355 DOI 10.17182/hepdata.44323

Photon diffractive dissociation, $\gamma p \to Xp$, has been studied at HERA with the ZEUS detector using $ep$ interactions where the virtuality $Q^2$ of the exchanged photon is smaller than 0.02 GeV$^2$. The squared four-momentum $t$ exchanged at the proton vertex was determined in the range $0.073<|t|<0.40$ GeV$^2$ by measuring the scattered proton in the ZEUS Leading Proton Spectrometer. In the photon-proton centre-of-mass energy interval $176<W<225$ GeV and for masses of the dissociated photon system $4<M_X<32$ GeV, the $t$ distribution has an exponential shape, $dN/d|t| \propto \exp{(-b|t|)}$, with a slope parameter $b=6.8 \pm 0.9$~(stat.)~$ ^{+1.2}_{-1.1}$~(syst.)~GeV$^{-2}$.

2 data tables match query

T is the squared four momentum transfer at the proton vertex.

SLOPE of the DN/DT distribution.


Diffraction dissociation in photoproduction at HERA

The H1 collaboration Adloff, C. ; Aid, S. ; Anderson, M. ; et al.
Z.Phys.C 74 (1997) 221-236, 1997.
Inspire Record 440126 DOI 10.17182/hepdata.44667

A study is presented of the process gamma p -->XY, where there is a large rapidity gap between the systems X and Y. Measurements are made of the differential cross section as a function of the invariant mass mx of the system produced at the photon vertex. Results are presented at centre of mass energies of W_gp = 187 GeV and W_gp = 231 GeV, both where the proton dominantly remains intact and, for the first time, where it dissociates. Both the centre of mass energy and the mx~2 dependence of HERA data and those from a fixed target experiment may simultaneously be described in a triple-Regge model. The low mass photon dissociation process is found to be dominated by diffraction, though a sizable subleading contribution is present at larger masses. The pomeron intercept is extracted and found to be alpha_pom(0) = 1.068 \pm 0.016 (stat.) \pm 0.022 (syst.) \pm 0.041 (model), in good agreement with values obtained from total and elastic hadronic and photoproduction cross sections. The diffractive contribution to the process gamma p --> Xp with mx~2 / W_gp~2 < 0.05 is measured to be 22.2 \pm 0.6 (stat.) \pm 2.6 (syst.) \pm 1.7 (model) % of the total gamma p cross section at W_gp = 187 GeV.

2 data tables match query

Data for proton remaining intact.

Data for proton dissociating.


Measurement of anti-p p single diffraction dissociation at s**(1/2) = 546-GeV and 1800-GeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.D 50 (1994) 5535-5549, 1994.
Inspire Record 359393 DOI 10.17182/hepdata.42542

We report a measurement of the diffraction dissociation differential cross section d2σSD/dM2dt for p¯p→p¯X at √s =546 and 1800 GeV, M2/s<0.2 and 0≤-t≤0.4 GeV2. Our results are compared to theoretical predictions and to extrapolations from experimental results at lower energies.

1 data table match query

Single diffraction dissociation cross section.


Double diffraction dissociation at the Fermilab Tevatron collider

The CDF collaboration Affolder, T. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 87 (2001) 141802, 2001.
Inspire Record 557212 DOI 10.17182/hepdata.42921

We present results from a measurement of double diffraction dissociation in $\bar pp$ collisions at the Fermilab Tevatron collider. The production cross section for events with a central pseudorapidity gap of width $\Delta\eta^0>3$ (overlapping $\eta=0$) is found to be $4.43\pm 0.02{(stat)}{\pm 1.18}{(syst) mb}$ [$3.42\pm 0.01{(stat)}{\pm 1.09}{(syst) mb}$] at $\sqrt{s}=1800$ [630] GeV. Our results are compared with previous measurements and with predictions based on Regge theory and factorization.

1 data table match query

Cross sections for double diffractive production.


Observation of diffractive W boson production at the Tevatron

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 78 (1997) 2698-2703, 1997.
Inspire Record 440095 DOI 10.17182/hepdata.42230

We report the first observation of diffractively produced W bosons. In a sample of W -> e nu events produced in p-barp collisions at sqrt{s}=1.8 TeV, we find an excess of events with a forward rapidity gap, which is attributed to diffraction. The probability that this excess is consistent with non-diffractive production is 1.1 10^{-4} (3.8 sigma). The relatively low fraction of W+Jet events observed within this excess implies that mainly quarks from the pomeron, which mediates diffraction, participate in W production. The diffractive to non-diffractive W production ratio is found to be R_W=(1.15 +/- 0.55)%.

1 data table match query

No description provided.


Measurement of the diffractive structure function F2(D(4) ) at HERA

The ZEUS collaboration Breitweg, J. ; Derrick, M. ; Krakauer, D. ; et al.
Eur.Phys.J.C 1 (1998) 81-96, 1998.
Inspire Record 448663 DOI 10.17182/hepdata.44431

This paper presents the first analysis of diffractive photon dissociation events in deep inelastic positron-proton scattering at HERA in which the proton in the final state is detected and its momentum measured. The events are selected by requiring a scattered proton in the ZEUS leading proton spectrometer (LPS) with $\xl>0.97$, where $\xl$ is the fraction of the incoming proton beam momentum carried by the scattered proton. The use of the LPS significantly reduces the contamination from events with diffractive dissociation of the proton into low mass states and allows a direct measurement of $t$, the square of the four-momentum exchanged at the proton vertex. The dependence of the cross section on $t$ is measured in the interval $0.073<|t|<0.4$~$\gevtwo$ and is found to be described by an exponential shape with the slope parameter $b=\tslopeerr$. The diffractive structure function $\ftwodfour$ is presented as a function of $\xpom \simeq 1-\xl$ and $\beta$, the momentum fraction of the struck quark with respect to $\xpom$, and averaged over the $t$ interval $0.073<|t|<\ftwodfourtmax$~$\gevtwo$ and the photon virtuality range $5<Q^2<20~\gevtwo$. In the kinematic range $4 \times 10^{-4} < \xpom < 0.03$ and $0.015<\beta<0.5$, the $\xpom$ dependence of $\ftwodfour$ is fitted with a form $\xpoma$, yielding $a= \ftwodfouraerr$. Upon integration over $t$, the structure function $\ftwod$ is determined in a kinematic range extending to higher $\xpom$ and lower $\beta$ compared to our previous analysis; the results are discussed within the framework of Regge theory.

4 data tables match query

The measured distribution of T, the squared momentum transfer to the virtual pluton.

Slope of the T distribution.

The structure function F2(NAME=D4).

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A Precise Determination of the Number of Families With Light Neutrinos and of the $Z$ Boson Partial Widths

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Lees, J.P. ; et al.
Phys.Lett.B 235 (1990) 399-411, 1990.
Inspire Record 284411 DOI 10.17182/hepdata.29743

More extensive and precise results are reported on the parameters of Z decay. On the basis of 20 000 Z decays collected with the ALEPH detector at LEP we find M z =91.182±0.026 (exp.) ±0.030 (beam) GeV, Γ z =2.541±0.056 GeV and σ had 0 =41.4±0.8 nb. The partial widths for the hadronic and leptonic channels are Γ had =1804±44 MeV, Γ e + e − =82.1±3.4 MeV, Γ μ + μ − =87.9±6.0 MeV and Γ τ + τ − =86.1±5.6 MeV, in good agreement with the standard model. On the basis of the average leptonic width Γ ℓ + ℓ − =83.9±2.2 MeV, the effective weak mixing angle is found to be sin 2 θ w ( M z )=0.231±0.008. Usin g the partial widths calculated in the standard model, the number of light neutrino families is N ν =3.01±0.15 (exp.)±0.05 (theor.).

1 data table match query

No description provided.


Measurement of the diffractive cross-section in deep inelastic scattering using ZEUS 1994 data

The ZEUS collaboration Breitweg, J. ; Derrick, M. ; Krakauer, D. ; et al.
Eur.Phys.J.C 6 (1999) 43-66, 1999.
Inspire Record 473108 DOI 10.17182/hepdata.44224

The DIS diffractive cross section, $d\sigma^{diff}_{\gamma^* p \to XN}/dM_X$, has been measured in the mass range $M_X < 15$ GeV for $\gamma^*p$ c.m. energies $60 < W < 200$ GeV and photon virtualities $Q^2 = 7$ to 140 GeV$^2$. For fixed $Q^2$ and $M_X$, the diffractive cross section rises rapidly with $W$, $d\sigma^{diff}_{\gamma^*p \to XN}(M_X,W,Q^2)/dM_X \propto W^{a^{diff}}$ with $a^{diff} = 0.507 \pm 0.034 (stat)^{+0.155}_{-0.046}(syst)$ corresponding to a $t$-averaged pomeron trajectory of $\bar{\alphapom} = 1.127 \pm 0.009 (stat)^{+0.039}_{-0.012} (syst)$ which is larger than $\bar{\alphapom}$ observed in hadron-hadron scattering. The $W$ dependence of the diffractive cross section is found to be the same as that of the total cross section for scattering of virtual photons on protons. The data are consistent with the assumption that the diffractive structure function $F^{D(3)}_2$ factorizes according to $\xpom F^{D(3)}_2 (\xpom,\beta,Q^2) = (x_0/ \xpom)^n F^{D(2)}_2(\beta,Q^2)$. They are also consistent with QCD based models which incorporate factorization breaking. The rise of $\xpom F^{D(3)}_2$ with decreasing $\xpom$ and the weak dependence of $F^{D(2)}_2$ on $Q^2$ suggest a substantial contribution from partonic interactions.

24 data tables match query

Cross section for diffractive scattering.

Cross section for diffractive scattering.

Cross section for diffracitve scattering.

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Improved measurements of electroweak parameters from Z decays into fermion pairs

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Goy, C. ; et al.
Z.Phys.C 53 (1992) 1-20, 1992.
Inspire Record 317141 DOI 10.17182/hepdata.14857

The properties of theZ resonance are measured on the basis of 190 000Z decays into fermion pairs collected with the ALEPH detector at LEP. Assuming lepton universality,Mz=(91.182±0.009exp±0.020L∶P) GeV,ГZ=(2484±17) MeV, σhad0=(41.44±0.36) nb, andГjad/Гℓℓ=21.00±0.20. The corresponding number of light neutrino species is 2.97±0.07. The forward-back-ward asymmetry in leptonic decays is used to determine the ratio of vector to axial-vector coupling constants of leptons:gv2(MZ2)/gA2(MZ2)=0.0072±0.0027. Combining these results with ALEPH results on quark charge and\(b\bar b\) asymmetries, and τ polarization, sin2θW(MZ2). In the contex of the Minimal Standard Model, limits are placed on the top-quark mass.

2 data tables match query

Statistical errors only.

No description provided.


Update of electroweak parameters from Z decays

The ALEPH collaboration Buskulic, D. ; Decamp, D. ; Goy, C. ; et al.
Z.Phys.C 60 (1993) 71-82, 1993.
Inspire Record 354298 DOI 10.17182/hepdata.47312

Based on 520 000 fermion pairs accumulated during the first three years of data collection by the ALEPH detector at LEP, updated values of the resonance parameters of theZ are determined to beMZ=(91.187±0.009) GeV, ΓZ=(2.501±0.012) GeV, σhad0=(41.60±0.27) nb, andRℓ=20.78±0.13. The corresponding number of light neutrino species isNν=2.97±0.05. The forward-backward asymmetry in lepton-pair decays is used to determine the ratio of vector to axial-vector couplings of leptons:gV2(MZ2)/gA2(MZ2)=0.0052±0.0016. Combining this with ALEPH measurements of theb andc quark asymmetries and τ polarization gives sin2θWeff=0.2326±0.0013. Assuming the minimal Standard Model, and including measurements ofMW/MZ fromp\(\bar p\) colliders and neutrino-nucleon scattering, the mass of the top quark is\(M_{top} = 156 \pm \begin{array}{*{20}c} {22} \\ {25} \\ \end{array} \pm \begin{array}{*{20}c} {17} \\ {22Higgs} \\ \end{array} \) GeV.

3 data tables match query

Data from 1990 running period.

Data from 1991 running period.

Data for 1991 running period.


Measurement of electroweak parameters from Z decays into Fermion pairs

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Goy, C. ; et al.
Z.Phys.C 48 (1990) 365-392, 1990.
Inspire Record 298414 DOI 10.17182/hepdata.47314

We report on the properties of theZ resonance from 62 500Z decays into fermion pairs collected with the ALEPH detector at LEP, the Large Electron-Positron storage ring at CERN. We findMZ=(91.193±0.016exp±0.030LEP) GeV, ΓZ=(2497±31) MeV, σhad0=(41.86±0.66)nb, and for the partial widths Γinv=(489±24) MeV, Γhad(1754±27) MeV, Γee=(85.0±1.6)MeV, Γμμ=(80.0±2.5) MeV, and Γττ=(81.3±2.5) MeV, all in good agreement with the Standard Model. Assuming lepton universality and using a lepton sample without distinction of the final state we measure Γu=(84.3±1.3) MeV. The forward-backward asymmetry in leptonic decays is used to determine the vector and axial-vector weak coupling constants of leptors,gv2(MZ2)=(0.12±0.12)×10−2 andgA2(MZ2)=0.2528±0.0040. The number of light neutrino species isNν=2.91±0.13; the electroweak mixing angle is sin2θW(MZ2)=0.2291±0.0040.

1 data table match query

No description provided.


Analyzing powers for pi p elastic scattering between 57 and 139 MeV

Patterson, J.D. ; Hofman, G.J. ; Brack, J.T. ; et al.
Phys.Rev.C 66 (2002) 025207, 2002.
Inspire Record 594648 DOI 10.17182/hepdata.25268

Analyzing powers for πp elastic scattering at bombarding energies below the Δ(1232) resonance were measured at TRIUMF using the CHAOS spectrometer and a polarized spin target. This work presents π− data at six incident energies of 57, 67, 87, 98, 117, and 139 MeV, and a single π+ data set at 139 MeV. The higher energy measurements cover an angular range of 72°<~θc.m.<~180° while the lower energies were limited to 101°<~θc.m.<~180°. There is a high degree of consistency between this work and the predictions of the VPI/GWU group’s SM95 partial wave analysis.

9 data tables match query

Analysing power measurements for a 139 GeV PI+ beam (standard track).

Analysing power measurements for a 139 GeV PI- beam (standard track).

Analysing power measurements for a 117 GeV PI- beam (standard track).

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Small Angle Elastic Scattering at the {CERN} Proton Anti-proton Collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 121 (1983) 77-82, 1983.
Inspire Record 180683 DOI 10.17182/hepdata.66558

3roton-antiproton elastic scattering at cm energy 540 GeV has been studied in the t range 0.14 ⩽ − t ⩽ 0.26 GeV 2 . The data is well fitted by an exponential form exp( bt ) with b = 13.3 ± 1.5 GeV −2 .

2 data tables match query

Elastic Differentiaol Cross Section (545 events). DATA REQUESTED 21 FEB 1983. Data read from plot in paper (29 JAN 2015).

No description provided.


Measurement of the polarization parameter in k+ p elastic scattering

Barnett, B.A. ; Laasanen, A.T. ; Koehler, P.F.M. ; et al.
Phys.Rev.D 8 (1973) 2751-2764, 1973.
Inspire Record 93326 DOI 10.17182/hepdata.22081

Full angular distributions of the polarization parameter in elastic K+p scattering at 1.37, 1.45, 1.60, 1.71, 1.80, 1.89, 2.11, and 2.31 GeV/c are presented. These data were obtained in an experiment at the Zero Gradient Synchrotron using a polarized proton target with arrays of scintillation and Čerenkov counters to detect the scattered particles.

8 data tables match query

No description provided.

No description provided.

No description provided.

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Measurement of the Spin Parameters a and A(nn) in $p p$ Elastic Scattering in the 1-{GeV}/$c$ to 3-{GeV}/$c$ Region

Bell, D.A. ; Buchanan, J.A. ; Calkin, M.M. ; et al.
Phys.Lett.B 94 (1980) 310-314, 1980.
Inspire Record 153380 DOI 10.17182/hepdata.27194

We have measured the asymmetry parameter A and the spin correlation parameter A nn in pp elastic scattering, using the Argonne ZGS polarized proton beam and a polarized proton target. Angular distributions of A and A nn for | t | ≳ 0.2 (GeV/ c ) 2 were obtained at eight momenta between 1.10 and 2 if 2.75 GeV/ c . We find significant structure in both the energy and t -dependence of A nn at these energies. At p lab ≈ 1.34 GeV/ c A nn reaches a very large value of about 0.8–0.9 near θ cm = 90°.

8 data tables match query

No description provided.

No description provided.

No description provided.

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Measurement of the total photon-proton cross-section and its decomposition at 200-GeV center-of-mass energy

The H1 collaboration Aid, S. ; Andreev, V. ; Andrieu, B. ; et al.
Z.Phys.C 69 (1995) 27-38, 1995.
Inspire Record 399015 DOI 10.17182/hepdata.44969

We present a new measurement of the total photoproduction cross section performed with the H1 detector at HERA. For an average centre of mass energy of 200GeV a value of $\sigma_{tot}~{\gamma{p}}= 165\pm2\pm11\mu$b has been obtained. A detailed analysis of the data in adequate kinematic regions enabled a decomposition of the total cross section in its elastic, single diffractive dissociation and remaining non-diffractive parts, based on safe assumptions on the double diffractive dissociation contribution.

1 data table match query

No description provided.


Hadron production in diffractive deep-inelastic scattering.

The H1 collaboration Adloff, C. ; Aid, S. ; Anderson, M. ; et al.
Phys.Lett.B 428 (1998) 206-220, 1998.
Inspire Record 468748 DOI 10.17182/hepdata.44324

Characteristics of hadron production in diffractive deep-inelastic positron-proton scattering are studied using data collected in 1994 by the H1 experiment at HERA. The following distributions are measured in the centre-of-mass frame of the photon dissociation system: the hadronic energy flow, the Feynman-x (x_F) variable for charged particles, the squared transverse momentum of charged particles (p_T^{*2}), and the mean p_T^{*2} as a function of x_F. These distributions are compared with results in the gamma^* p centre-of-mass frame from inclusive deep-inelastic scattering in the fixed-target experiment EMC, and also with the predictions of several Monte Carlo calculations. The data are consistent with a picture in which the partonic structure of the diffractive exchange is dominated at low Q^2 by hard gluons.

6 data tables match query

Energy flow distributions in the gamma*-pomeron CM frame.. Positive etarap corresponds to the direction of the incoming photon.

Energy flow distributions in the gamma*-pomeron CM frame.. Positive etarap corresponds to the direction of the incoming photon.

Energy flow distributions in the gamma*-pomeron CM frame.. Positive etarap corresponds to the direction of the incoming photon.

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Study of photon dissociation in diffractive photoproduction at HERA

The ZEUS collaboration Breitweg, J. ; Derrick, M. ; Krakauer, D. ; et al.
Z.Phys.C 75 (1997) 421-435, 1997.
Inspire Record 442287 DOI 10.17182/hepdata.10933

Diffractive dissociation of quasi-real photons at a photon-proton centre of mass energy of W 200 GeV is studied with the ZEUS detector at HERA. The process under consideration is gamma p -> X N, where X is the diffractively dissociated photon system of mass M_X and N is either a proton or a nucleonic system with mass M_N < 2GeV. The cross section for this process in the interval 3 < M_X < 24 GeV relative to the total photoproduction cross section was measured to be sigma~partial_D / sigma_tot = 6.2 +- 0.2(stat) +- 1.4(syst)%. After extrapolating this result to the mass interval of m_phi~2 < M_X~2 < 0.05 W~2 and correcting it for proton dissociation, the fraction of the total cross section attributed to single diffractive photon dissociation, gamma p -> X p, is found to be sigma_SD / sigma_tot = 13.3 +- 0.5(stat) +- 3.6(syst)%. The mass spectrum of the dissociated photon system in the interval 8 < M_X < 24 GeV can be described by the triple pomeron (PPP) diagram with an effective pomeron intercept of alpha_P(0) = 1.12 +- 0.04(stat) +- 0.08(syst). The cross section for photon dissociation in the range 3 < M_X < 8 GeV is significantly higher than that expected from the triple pomeron amplitude describing the region 8 < M_X < 24 GeV. Assuming that this discrepancy is due to a pomeron-pomeron-reggeon (PPR) term, its contribution to the diffractive cross section in the interval 3 < M_X < 24 GeV is estimated to be f_PPR = 26 +- 3(stat) +- 12(syst)%.

4 data tables match query

Fraction of the total photoproduction cross section attributed to the photon dissociation.

The fraction of the total photoproduction cross section due to single dif fractive photon dissociation, in the mass range M_phi**2 < M_DD < X >**2 < 0.05 *W**2.

Identification of the diffractive processes was performed on the basis of the shape of reconstructed hadronic mass spectrum. No rapidity-gap was required.

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Pi-minus p elastic scattering at 2.26 gev/c

Reynolds, B.G. ; Kimel, J.D. ; Albright, John R. ; et al.
Phys.Rev. 173 (1968) 1403-1411, 1968.
Inspire Record 55955 DOI 10.17182/hepdata.26498

The elastic scattering of negative pions on protons at 2.26 GeVc has been studied using the Lawrence Radiation Laboratory 72-in. hydrogen-filled bubble chamber. The elastic scattering cross section is found to be 8.91±0.24 mb. The forward diffraction peak is well fitted by an exponential in the square of the four-momentum transfer, and the slope is found to be 8.8±0.1 GeV−2. The differential cross section is parametrized in terms of three models: optical, strong-absorption, and two-slope. It is found that the two-slope model affords the best description of the data and also does very well in predicting the polarization data of other experiments. The best-fit parameters for all three models are given. In addition, the amplitudes associated with the best fits are given for the strong-absorption and the two-slope models.

1 data table match query

No description provided.


Operation and Performance of a System for $\pi p$ and $\pi D$ Backward Scattering

Stanovnik, A. ; Kernel, G. ; Tanner, N.W. ; et al.
Nucl.Instrum.Meth. 177 (1980) 369, 1980.
Inspire Record 152948 DOI 10.17182/hepdata.41451

A simple, large-solid-angle apparatus, specially suited for the measurement of backward elastic scattering of medium-energy pions on protons and deuterons, is described. The method of analysis which reduces background and determines elastic events from a data sample of 185 MeV negative pions incident on a D 2 O target is discussed. Results for 141 MeV π + p and 185 MeV π − p backward cross-sections are also presented and compared with cross-sections calculated from known phase shifts.

2 data tables match query

pi+- p differential cross sections at low energies.

Denz, H. ; Amaudruz, P. ; Brack, J.T. ; et al.
Phys.Lett.B 633 (2006) 209-213, 2006.
Inspire Record 699647 DOI 10.17182/hepdata.31620

Differential cross sections for pi- p and pi+ p elastic scattering were measured at five energies between 19.9 and 43.3 MeV. The use of the CHAOS magnetic spectrometer at TRIUMF, supplemented by a range telescope for muon background suppression, provided simultaneous coverage of a large part of the full angular range, thus allowing very precise relative cross section measurements. The absolute normalisation was determined with a typical accuracy of 5 %. This was verified in a simultaneous measurement of muon proton elastic scattering. The measured cross sections show some deviations from phase shift analysis predictions, in particular at large angles and low energies. From the new data we determine the real part of the isospin forward scattering amplitude.

12 data tables match query

Elastic PI- P cross section for incident kinetic energy 43.3 MeV for the rotated target data. Errors shown are statistical only.

Elastic PI- P cross section for incident kinetic energy 43.3 MeV. Errors shown are statistical only.

Elastic PI- P cross section for incident kinetic energy 37.1 MeV. Errors shown are statistical only.

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The n n scattering amplitude at 845 mev/c

Dutton, L.M.C. ; Howells, R.J.W. ; Jafar, J.D. ; et al.
Nucl.Phys.B 78 (1974) 484-492, 1974.
Inspire Record 94570 DOI 10.17182/hepdata.32243

Experimental data on dd small-angle elastic scattering in the Coulomb interference region are analysed to yield the dd scattering amplitude. This amplitude is then expressed in terms of the nucleon-nucleon scattering amplitudes and the Glauber correction. The value for the nn scattering amplitude found is shown to be in good agreement with the pp amplitude.

1 data table match query

No description provided.


Backward $\pi d$ Scattering Between 140-{MeV} and 260-{MeV}

The OMICRON collaboration Stanovnik, A. ; Kernel, G. ; Tanner, N.W. ; et al.
Phys.Lett.B 94 (1980) 323-326, 1980.
Inspire Record 153157 DOI 10.17182/hepdata.27191

Differential cross sections for elastic scattering of pions by deuterons have been measured for centre-of-mass angles between 130° and 175°, and at laboratory energies 141, 177, and 260 MeV for π + , and at 151, 185, and 189 MeV for π − . At 177 and 260 MeV the cross sections are a factor of 2 lower than the predictions of three-body theories.

6 data tables match query

No description provided.

No description provided.

No description provided.

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Measurement of hadron and lepton pair production from e+ e- annihilation at center-of-mass energies of 130-GeV and 136-GeV

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.
Phys.Lett.B 378 (1996) 373-384, 1996.
Inspire Record 421552 DOI 10.17182/hepdata.47801

Hadronic and leptonic cross-sections and forward-backward asymmetries are measured using 5.7 pb −1 of data taken with the ALEPH detector at LEP at centre-of-mass energies of 130 and 136 GeV. The results agree with Standard Model expectations. The measurement of hadronic cross-sections far away from the Z resonance improves the determination of the interference between photon and Z exchange. Constraints on models with extra Z bosons are presented.

2 data tables match query

Data with tight SPRIME cut.

Forward-Backward Asymmetry for tight SPRIME cuts.


Measurement of small angle anti-proton - proton elastic scattering at S**(1/2) = 546-GeV and 1800-GeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.D 50 (1994) 5518-5534, 1994.
Inspire Record 359411 DOI 10.17182/hepdata.22369

Antiproton-proton elastic scattering was measured at c.m.s. energies √s =546 and 1800 GeV in the range of four-momentum transfer squared 0.025<-t<0.29 GeV2. The data are well described by the exponential form ebt with a slope b=15.28±0.58 (16.98±0.25) GeV−2 at √s =546 (1800) GeV. The elastic scattering cross sections are, respectively, σel=12.87±0.30 and 19.70±0.85 mb.

4 data tables match query

Final results (systematic errors included).

Final results (systematic errors included).

Statistical errors only. Data supplied by S. Belforte.

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D*+- meson production in deep-inelastic diffractive interactions at HERA.

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Phys.Lett.B 520 (2001) 191-203, 2001.
Inspire Record 562188 DOI 10.17182/hepdata.46767

A measurement is presented of the cross section for D* meson production in diffractive deep-inelastic scattering for the first time at HERA. The cross section is given for the process ep -> eXY, where the system X contains at least one D* meson and is separated by a large rapidity gap from a low mass proton remnant system Y. The cross section is presented in the diffractive deep-inelastic region defined by 2< Q^2 < 100 GeV^2, 0.05 < y < 0.7, x_pom < 0.04, M_Y < 1.6 GeV and |t| < 1 GeV^2. The D* mesons are restricted to the range ptD* > 2 GeV and |\eta_D* | < 1.5. The cross section is found to be 246+-54+-56 pb and forms about 6% of the corresponding inclusive D* cross section. The cross section is presented as a function of various kinematic variables, including z_pom^obs which is an estimate of the fraction of the momentum of the diffractive exchange carried by the parton entering the hard-subprocess. The data show a large component of the cross section at low z_pom^obs where the contribution of the Boson-Gluon-Fusion process is expected to dominate. The data are compared with several QCD--based calculations.

7 data tables match query

The total D*+- production cross section for the given kinematic region. Also given is the ratio to the DIS*+- production cross section in the samekinematic region.

Cross section as a function of X(NAME=POMERON).

Cross section as a function of LOG10(BETA). BETA = X/X(NAME=POMERON).

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K+ n Elastic and Charge Exchange Scattering Between 430-MeV/c and 940-MeV/c

Damerell, C.J.S. ; Hotchkiss, M.J. ; Wickens, F. ; et al.
Nucl.Phys.B 94 (1975) 374-412, 1975.
Inspire Record 98726 DOI 10.17182/hepdata.31976

Elastic and charge-exchange K + n differential cross sections have been measured from K + d interactions from 430 to 940 MeV/ c using spark chambers and scintillation counters. The data have been compared with existing results and in an accompanying paper have been included with other measurements in a phase-shift analysis.

3 data tables match query

NOTE COHERENT ELASTIC SCATTERING ON DEUTERIUM AT FORWARD ANGLES (-T < 0.13 GEV**2) REDUCES THE CROSS SECTION COMPARED WITH FREE NUCLEON ELASTIC SCATTERING.

NOTE COHERENT ELASTIC SCATTERING ON DEUTERIUM AT FORWARD ANGLES (-T < 0.13 GEV**2) REDUCES THE CROSS SECTION COMPARED WITH FREE NUCLEON ELASTIC SCATTERING.

SUM OF BREAK-UP AND COHERENT ELASTIC REACTIONS.


Deep inelastic inclusive and diffractive scattering at $Q^2$ values from 25 to 320 GeV$^2$ with the ZEUS forward plug calorimeter

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Nucl.Phys.B 800 (2008) 1-76, 2008.
Inspire Record 779854 DOI 10.17182/hepdata.11639

Deep inelastic scattering and its diffractive component, $ep \to e^{\prime}\gamma^* p \to e^{\prime}XN$, have been studied at HERA with the ZEUS detector using an integrated luminosity of 52.4 pb$^{-1}$. The $M_X$ method has been used to extract the diffractive contribution. A wide range in the centre-of-mass energy $W$ (37 -- 245 GeV), photon virtuality $Q^2$ (20 -- 450 GeV$^2$) and mass $M_X$ (0.28 -- 35 GeV) is covered. The diffractive cross section for $2 < M_X < 15$ GeV rises strongly with $W$, the rise becoming steeper as $Q^2$ increases. The data are also presented in terms of the diffractive structure function, $F^{\rm D(3)}_2$, of the proton. For fixed $Q^2$ and fixed $M_X$, $\xpom F^{\rm D(3)}_2$ shows a strong rise as $\xpom \to 0$, where $\xpom$ is the fraction of the proton momentum carried by the Pomeron. For Bjorken-$x < 1 \cdot 10^{-3}$, $\xpom F^{\rm D(3)}_2$ shows positive $\log Q^2$ scaling violations, while for $x \ge 5 \cdot 10^{-3}$ negative scaling violations are observed. The diffractive structure function is compatible with being leading twist. The data show that Regge factorisation is broken.

208 data tables match query

Cross section for diffractive scattering GAMMA* P --> DD X where M(DD) < 2.3 GeV and M(X) = 1.2 GeV for Q**2 = 25 GeV**2.

Cross section for diffractive scattering GAMMA* P --> DD X where M(DD) < 2.3 GeV and M(X) = 1.2 GeV for Q**2 = 35 GeV**2.

Cross section for diffractive scattering GAMMA* P --> DD X where M(DD) < 2.3 GeV and M(X) = 1.2 GeV for Q**2 = 45 GeV**2.

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Measurement of K- p Elastic Differential Cross-Sections Between 610-MeV/c and 943-MeV/c

Adams, C.J. ; Davies, J.D. ; Dowell, J.D. ; et al.
Nucl.Phys.B 96 (1975) 54-66, 1975.
Inspire Record 2402 DOI 10.17182/hepdata.31930

Measurements of K − p elastic scattering have been carried out at 14 momenta between 610 MeV/ c and 943 MeV/ c over the angular range −0.9 < cos θ < 0.9. The results agree well with the best existing data and have significantly smaller errors.

4 data tables match query

No description provided.

DIFFERENTIAL CROSS SECTION AT 0 DEG CALCULATED FROM DISPERSION RELATIONS AND AT 180 DEG INTERPOLATED FROM BUBBLE CHAMBER MEASUREMENTS.

LEGENDRE POLYNOMIAL FIT, INCLUDING FORWARD AND BACKWARD POINTS.

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Diffractive Photoproduction of D*+/-(2010) at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Eur.Phys.J.C 51 (2007) 301-315, 2007.
Inspire Record 747652 DOI 10.17182/hepdata.45627

Diffractive photoproduction of D*+/-(2010) mesons was measured with the ZEUS detector at the ep collider HERA, using an integrated luminosity of 78.6 pb^{-1}. The D* mesons were reconstructed in the kinematic range: transverse momentum p_T(D*) > 1.9 GeV and pseudorapidity |eta(D*)| < 1.6, using the decay D*+ -> D0 pi+_s followed by D0 -> K- pi+ (+c.c.). Diffractive events were identified by a large gap in pseudorapidity between the produced hadronic state and the outgoing proton. Cross sections are reported for photon-proton centre-of-mass energies in the range 130 < W < 300 GeV and for photon virtualities Q^2 < 1 GeV^2, in two ranges of the Pomeron fractional momentum x_pom < 0.035 and x_pom < 0.01. The relative contribution of diffractive events to the inclusive D*+/-(2010) photoproduction cross section is about 6%. The data are in agreement with perturbative QCD calculations based on various parameterisations of diffractive parton distribution functions. The results are consistent with diffractive QCD factorisation.

12 data tables match query

Total cross section integrated over the given kinematic range.

Ratio of diffractive to inclusive D* cross section.

Differential cross sections for diffractive photoproduction of D*+- mesons as a function of X(NAME=POMERON).

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Compton scattering by the proton through Theta(CMS) = 75-degrees and 90-degrees in the Delta resonance region

Hünger, A ; Peise, J ; Robbiano, A ; et al.
Nucl.Phys.A 620 (1997) 385-416, 1997.
Inspire Record 458618 DOI 10.17182/hepdata.36349

Differential cross sections for Compton scattering by the proton have been measured in the energy interval between 200 and 500 MeV at scattering angles of θ cms = 75° and θ cms = 90° using the CATS, the CATS/TRAJAN, and the COPP setups with the Glasgow Tagger at MAMI (Mainz). The data are compared with predictions from dispersion theory using photo-meson amplitudes from the recent VPI solution SM95. The experiment and the theoretical procedure are described in detail. It is found that the experiment and predictions are in agreement as far as the energy dependence of the differential cross sections in the Δ-range is concerned. However, there is evidence that a scaling down of the resonance part of the M 1+ 3 2 photo-meson amplitude by (2.8 ± 0.9)% is required in comparison with the VPI analysis. The deduced value of the M 1+ 3 2 - photoproduction amplitude at the resonance energy of 320 MeV is: |M 1+ 3 2 | = (39.6 ± 0.4) × 10 −3 m π + −1 .

2 data tables match query

No description provided.

No description provided.


K- n Elastic Scattering Between 610-MeV/c and 840-MeV/c

Damerell, C.J.S. ; Hotchkiss, M.J. ; Wickens, F. ; et al.
Nucl.Phys.B 129 (1977) 397-414, 1977.
Inspire Record 126184 DOI 10.17182/hepdata.35225

Elastik K − n ( I = 1) differential cross sections have been measured at 14 momenta between 610 and 940 MeV/ c , over the c.m. angular range −0.7 < cos θ ∗ < 0.8 . The results, which cover the c.m. energy range 1610–1765 MeV, have been fitted with Legendre polynomials and compared with some existing predictions from a partial-wave analysis.

6 data tables match query

No description provided.

No description provided.

SEMI-INCLUSIVE CROSS SECTION.

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Spin Effects in $p p$ Elastic Scattering at 28-{GeV}/$c$

Hansen, P.H. ; O'Fallon, J.R. ; Danby, G.T. ; et al.
Phys.Rev.Lett. 50 (1983) 802, 1983.
Inspire Record 182130 DOI 10.17182/hepdata.20535

The analyzing power, A, was measured in proton-proton elastic scattering with use of a polarized proton target and 28-GeV/c primary protons from the alternating-gradient synchrotron. Over the P⊥2 range of 0.5 to 2.8 (GeV/c)2, the data show interesting structure. There is a rather sharp dip at P⊥2=0.8 (GeV/c)2 corresponding to the break in the elastic differential cross section at the end of the diffraction peak.

1 data table match query

No description provided.


Diffractive jet production in deep inelastic e+ p collisions at HERA

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Eur.Phys.J.C 20 (2001) 29-49, 2001.
Inspire Record 539087 DOI 10.17182/hepdata.46939

A measurement is presented of dijet and 3-jet cross sections in low-|t| diffractive deep-inelastic scattering interactions of the type ep -> eXY, where the system X is separated by a large rapidity gap from a low-mass baryonic system Y. Data taken with the H1 detector at HERA, corresponding to an integrated luminosity of 18.0 pb^(-1), are used to measure hadron level single and double differential cross sections for 4<Q^2<80 GeV^2, x_pom<0.05 and p_(T,jet)>4 GeV. The energy flow not attributed to jets is also investigated. The measurements are consistent with a factorising diffractive exchange with trajectory intercept close to 1.2 and tightly constrain the dominating diffractive gluon distribution. Viewed in terms of the diffractive scattering of partonic fluctuations of the photon, the data require the dominance of qqbarg over qqbar states. Soft colour neutralisation models in their present form cannot simultaneously reproduce the shapes and the normalisations of the differential cross sections. Models based on 2-gluon exchange are able to reproduce the shapes of the cross sections at low x_pom values.

24 data tables match query

Average values, over the specified interval, of the differential hadron level dijet cross section as a function of Q**2.

Average values, over the specified interval, of the differential hadron level dijet cross section as a function of the average transverse momentum of the two jets in the c.m.frame.

Average values, over the specified interval, of the differential hadron level dijet cross section as a function of the average pseudorapidity of the two jets in the lab frame.

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K+ p elastic scattering between 432 and 939 mev/c and phase shift analysis

Adams, C.J. ; Cox, G.F. ; Davies, J.D. ; et al.
Nucl.Phys.B 66 (1973) 36-77, 1973.
Inspire Record 94900 DOI 10.17182/hepdata.32390

Measurements of K + p elastic scattering have been carried out at 13 momenta between 432 MeV/ c and 939 MeV/ c using spark chambers. The data establish unambiguously the constructive interference of the Coulomb and nuclear amplitudes at 432 MeV/ c . The elastic cross section is found to be independent of momentum through the range covered. The phase shifts for S, P, D and F waves are obtained in an energy dependent analysis in which higher waves are held at theoretical values. The initial behaviour ofthe P, D and F amplitudes is quite close to that predicted by the calculation of the peripheral partial waves. Only the P3 and D5 amplitudes become strikingly different with increasing momentum.

14 data tables match query

COULOMB INTERFERENCE EFFECT SEEN AT SMALL ANGLES.

No description provided.

No description provided.

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K+ p elastic scattering between 432 and 939 mev/c

Adams, C.J. ; Davies, J.D. ; Dowell, J.D. ; et al.
Phys.Rev.D 4 (1971) 2637-2641, 1971.
Inspire Record 74758 DOI 10.17182/hepdata.23177

We present data from a spark-chamber study of K+p elastic scattering between 432 and 939 MeV/c, over the range −0.6<cosθc.m.<+0.7. With measurements at 13 momenta, and between 2000 events at the lowest momentum and 5000 events at the highest momentum, there is a major improvement over previous data. The elastic cross sections deduced from the differential cross sections are almost independent of momentum through the range covered. The data are inconsistent with counter measurements of the total cross section which suggest a sharp shoulder in the cross section at about 700 MeV/c.

14 data tables match query

No description provided.

No description provided.

No description provided.

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