Recent results on diffraction from the H1 and ZEUS experiments at HERA are presented. Measurement of open charm production in diffractive DIS has been performed by the H1 experiment using the event topology, given by ep → eXY, where the system X, containing at least one D*(2010) meson, is separated from a leading low-mass proton dissociative system Y by a large rapidity gap. The photoproduction of isolated photons is measured using diffractive events recorded by the ZEUS experiment. Cross sections are evaluated in the photon transverse-energy and pseudorapidity ranges 5 < EγT < 15 GeV and -0:7 < ηγ < 0:9, inclusively and with a jet with transverse-energy and pseudorapidity in the ranges 4 < EjetT < 35 GeV and -1:5 < ηjet < 1:8. The exclusive deep inelastic electroproduction and photoproduction of Ψ(2S ) and J=Ψ(1S) mesons has been also studied by ZEUS. The cross-section ratio σ(Ψ(2S))=σ(J=Ψ(1S)) has been measured as a function of Q2, W and t. The results are compared to several predictions of QCD-inspired models, providing tests of the models in a region of soft to hard diffraction.

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New cross sections for the27Al(p,x)7Be nuclear process: Monitoring proton beam energy via the22Na/7Be cross-section ratio between 45 and 200 MeV

EPJ Web of Conferences ◽

10.1051/epjconf/201714608011 ◽

2017 ◽

Vol 146 ◽

pp. 08011 ◽

Cited By ~ 1

Author(s):

Ferenc Szelecsényi ◽

Gideon Francois Steyn ◽

Francois Meiring Nortier ◽

Zoltán Kovács

Keyword(s):

Proton Beam ◽

Cross Section ◽

Process Monitoring ◽

Cross Sections ◽

Beam Energy ◽

Cross Section Ratio ◽

Section Ratio ◽

Nuclear Process ◽

Proton Beam Energy

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Total-to-K-shell photoelectric cross-section ratios in some rare-earth and high-Z elements

Canadian Journal of Physics ◽

10.1139/p89-022 ◽

1989 ◽

Vol 67 (2-3) ◽

pp. 139-142 ◽

Cited By ~ 1

Author(s):

S. Chandra Lingam ◽

K. Suresh Babu ◽

V. Prakash Kumar ◽

D. V. Krishna Reddy

Keyword(s):

Rare Earth ◽

Cross Section ◽

Atomic Number ◽

Cross Sections ◽

Cross Section Ratio ◽

Section Ratio ◽

Photoelectric Cross Section ◽

Normal Transmission ◽

Experimental Values ◽

Good Agreement

The total photoelectric cross-sections in the elements gadolinium, dysprosium, erbium, lutetium, tantalum, tungsten, gold, and lead have been obtained by using the normal transmission experiments, and the results are reported. Using these total photoelectric cross sections, we have found the K-shell photoelectric cross sections, the K-jump ratios, and the total-to-K-shell photoelectric cross-section ratios at the K edges for the above elements. These values are compared with the available theoretical and experimental values. The results are in good agreement with the Storm and Israel results and the Scofield theoretical values, within the limits of experimental uncertainties. Furthermore, the variation of the total-to-K-shell photoelectric cross-section ratio with energy and atomic number is discussed.

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Activation cross section and isomeric cross-section ratio for the (n,2n) reaction on 132,134Ba

Radiochimica Acta ◽

10.1515/ract-2017-2768 ◽

2017 ◽

Vol 105 (10) ◽

Cited By ~ 6

Author(s):

Junhua Luo ◽

Chunlei Wu ◽

Li Jiang ◽

Suyuan Li

Keyword(s):

Cross Section ◽

Cross Sections ◽

Cross Section Ratio ◽

Activation Cross Section ◽

Section Ratio ◽

Isomeric Cross Section Ratio

AbstractCross sections of the

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STUDY OF ISOMERIC CROSS-SECTION RATIO AND PRE-EQUILIBRIUM FRACTION IN PROTON AND ALPHA PARTICLE INDUCED NUCLEAR REACTIONS ON 197Au

International Journal of Modern Physics E ◽

10.1142/s0218301312500590 ◽

2012 ◽

Vol 21 (06) ◽

pp. 1250059 ◽

Cited By ~ 7

Author(s):

B. SATHEESH ◽

M. M. MUSTHAFA ◽

B. P. SINGH ◽

R. PRASAD

Keyword(s):

Cross Section ◽

Cross Sections ◽

Nuclear Reactions ◽

Energy Difference ◽

Activation Technique ◽

Cross Section Ratio ◽

Excitation Functions ◽

Section Ratio ◽

Isomeric Cross Section Ratio ◽

Equilibrium Emission

Excitation functions for the reactions 197 Au(p,n) 197g Hg and 197 Au(p,n) 197m Hg have been measured over the energy ranges from threshold up to 20 MeV using stacked foil activation technique. The isomeric cross-section ratio σm/(σm+σg) for the formation of 197g, m Hg was determined. The excitation functions and isomeric cross-section ratios were calculated for the reactions 197 Au(p,n) 197g,m Hg , 197 Au(p,2n) 196 Hg , 197 Au(p,3n) 195g,m Hg , 197 Au(p,4n) 194 Hg , 197 Au(p,5n) 193g,m Hg , 197 Au (α, n )200 Tl , 197 Au (α, 2n )199 Tl , 197 Au (α, 3n )198g,m Tl , 197 Au (α, 4n )197 Tl and 197 Au (α, 5n )196g,m Tl from reaction threshold up to 40 MeV for proton induced reactions and 80 MeV for alpha induced reactions. The results were compared with the theoretical cross-sections calculated by means of the code EMPIRE-II and with the available literature data, which makes use of the Hauser Feshbach model for the compound nuclear calculations and the exciton model for the pre-equilibrium emission part. The isomeric cross-section ratio is found to depend strongly on the relative spins of the isomeric and ground state, energy difference between the levels, presence of intermediate states and some dependence on decay modes and on the onset of pre-equilibrium emission.

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