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B. Badełek J. Kwiecinski B. Ziaja 《The European Physical Journal C - Particles and Fields》2002,26(1):45-49
Theoretical predictions for the polarized nucleon structure function g
1
(x, Q
2
) at low Q2 are obtained in the framework of the generalized vector meson dominance model. Contributions from both light and heavy vector
mesons are evaluated. In the photoproduction limit the first moment of g1 is related to the static properties of the nucleon via the Drell-Hearn-Gerasimov-Hosoda-Yamamoto sum rule. This property
is employed to fix the magnitude of the light vector meson contribution to g1, using the recent measurements in the region of baryonic resonances. The results are compared to the data on g
1
(x, Q
2
). Finally, the DHGHY moment function I(Q
2
) is calculated, and our theoretical predictions are confronted with the recent preliminary data obtained at the Jefferson
Laboratory.
Received: 9 July 2002 / Published online: 7 October 2002
RID="a"
ID="a" e-mail: badelek@fuw.edu.pl
RID="b"
ID="b" e-mail: jan.kwiecinski@ifj.edu.pl
RID="c"
ID="c" e-mail: ziaja@tsl.uu.se 相似文献
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Fatemi R Skabelin AV Burkert VD Crabb D De Vita R Kuhn SE Minehart R Adams G Anciant E Anghinolfi M Asavapibhop B Audit G Auger T Avakian H Bagdasaryan H Ball JP Barrow S Battaglieri M Beard K Bektasoglu M Bellis M Bertozzi W Bianchi N Biselli AS Boiarinov S Bonner BE Bosted PE Bouchigny S Bradford R Branford D Brooks WK Butuceanu C Calarco JR Carman DS Carnahan B Cetina C Ciciani L Clark R Cole PL Coleman A Connelly J Cords D Corvisiero P Crannell H Cummings JP De Sanctis E Degtyarenko PV 《Physical review letters》2003,91(22):222002
Double-polarization asymmetries for inclusive ep scattering were measured at Jefferson Lab using 2.6 and 4.3 GeV longitudinally polarized electrons incident on a longitudinally polarized NH3 target in the CLAS detector. The polarized structure function g(1)(x,Q2) was extracted throughout the nucleon resonance region and into the deep inelastic regime, for Q(2)=0.15-1.64 GeV2. The contributions to the first moment Gamma(1)(Q2)= integral g(1)(x,Q2) dx were determined up to Q(2)=1.2 GeV2. Using a parametrization for g(1) in the unmeasured low x regions, the complete first moment was estimated over this Q2 region. A rapid change in Gamma(1) is observed for Q2<1 GeV2, with a sign change near Q(2)=0.3 GeV2, indicating dominant contributions from the resonance region. At Q(2)=1.2 GeV2 our data are below the perturbative QCD evolved scaling value. 相似文献
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《Zeitschrift fur Physik C Particles and Fields》1996,69(4):607-620
We report on a measurement of the proton structure function F 2 in the range 3.5 × 10?5 ≤ x ≤ 4 × 10?3 and 1.5 GeV2 ≤ Q 2 ≤ 15 GeV2 at the ep collider HERA operating at a centre-of-mass energy of ${sqrt s} = 300 {? GeV}$. The rise of F 2 with decreasing x observed in the previous HERA measurements persists in this lower x and Q 2 range. The Q 2 evolution of F 2, even at the lowest Q 2 and x measured, is consistent with perturbative QCD. 相似文献
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Anthony PL Arnold RG Band HR Borel H Bosted PE Breton V Cates GD Chupp TE Dietrich FS Dunne J Erbacher R Fellbaum J Fonvieille H Gearhart R Holmes R Hughes EW Johnson JR Kawall D Keppel C Kuhn SE Lombard-Nelsen RM Marroncle J Maruyama T Meyer W Meziani Z Middleton H Morgenstern J Newbury NR Petratos GG Pitthan R Prepost R Roblin Y Rock SE Rokni SH Shapiro G Smith T Souder PA Spengos M Staley F Stuart LM Szalata ZM Terrien Y Thompson AK White JL Woods M Xu J Young CC Zapalac G 《Physical review letters》1993,71(7):959-962
8.
We obtain a relation between the longitudinal structure function F
L(x, Q
2), F
2(x, Q
2) and G(x, Q
2) at small x, using the formalism recently reported by one of the authors [2]. We also obtain a relation between F
L(x, Q
2), F
2(x, Q
2) and its slope (dF
2(x, Q
2))/(dlnQ
2). This provides us with the determination of the longitudinal structure function F
L(x, Q
2) from F
2(x, Q
2) data and hence extract the gluon distribution G(x, Q
2). 相似文献
9.
B.I. Ermolaev M. Greco S.I. Troyan 《The European Physical Journal C - Particles and Fields》2007,51(4):859-866
We show that (∼1/(Q2)k) power corrections to the spin structure function g1 at small x are generated perturbatively from the regulated infrared divergencies. We present the explicit series of such
terms as well as the formulae for their resummation. These contributions are not included in the standard analysis of the
experimental data. We argue that accounting for such terms can sizably change the impact of the power corrections conventionally
attributed to the higher twists.
PACS 12.38.Cy 相似文献
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Amarian M Auerbach L Averett T Berthot J Bertin P Bertozzi B Black T Brash E Brown D Burtin E Calarco J Cates G Chai Z Chen JP Choi S Chudakov E Cisbani E De Jager CW Deur A DiSalvo R Dieterich S Djawotho P Finn M Fissum K Fonvieille H Frullani S Gao H Gao J Garibaldi F Gasparian A Gilad S Gilman R Glamazdin A Glashausser C Goldberg E Gomez J Gorbenko V Hansen JO Hersman B Holmes R Huber GM Hughes E Humensky B Incerti S Iodice M Jensen S Jiang X Jones C Jones G Jones M Jutier C Ketikyan A 《Physical review letters》2004,92(2):022301
We have measured the spin structure functions g(1) and g(2) of 3He in a double-spin experiment by inclusively scattering polarized electrons at energies ranging from 0.862 to 5.058 GeV off a polarized 3He target at a 15.5 degrees scattering angle. Excitation energies covered the resonance and the onset of the deep inelastic regions. We have determined for the first time the Q2 evolution of Gamma(1)(Q2)= integral (1)(0)g(1)(x,Q2)dx, Gamma(2)(Q2)= integral (1)(0)g(2)(x,Q2)dx, and d(2)(Q2)= integral (1)(0)x(2)[2g(1)(x,Q2)+3g(2)(x,Q2)]dx for the neutron in the range 0.1< or =Q2< or =0.9 GeV2 with good precision. Gamma(1)(Q2) displays a smooth variation from high to low Q2. The Burkhardt-Cottingham sum rule holds within uncertainties and d(2) is nonzero over the measured range. 相似文献
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Aihara H Alston-Garnjost M Avery RE Barbaro-Galtieri A Barker AR Barnes AV Barnett BA Bauer DA Bengtsson pH Bintinger DL Bobbink GJ Bolognese TS Bross AD Buchanan CD Buijs A Caldwell DO Clark AR Cowan GD Crane DA Dahl OI Derby KA Eastman JJ Eberhard PH Edberg TK Eisner AM Enomoto R Erné FC Fujii T Gary JW Gorn W Hauptman JM Hofmann W Huth JE Hylen J Kamae T Kaye HS Kees KH Kenney RW Kerth LT Ko W Koda RI Kofler RR Kwong KK Lander RL Langeveld WG Layter JG Linde FL Lindsey CS Loken SC Lu A Lu XQ 《Physical review letters》1987,58(2):97-100
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Abe K Akagi T Anthony PL Antonov R Arnold RG Averett T Band HR Bauer JM Borel H Bosted PE Breton V Button-Shafer J Chen JP Chupp TE Clendenin J Comptour C Coulter KP Court G Crabb D Daoudi M Day D Dietrich FS Dunne J Dutz H Erbacher R Fellbaum J Feltham A Fonvieille H Frlez E Garvey D Gearhart R Gomez J Grenier P Griffioen KA Hoibraten S Hughes EW Hyde-Wright C Johnson JR Kawall D Klein A Kuhn SE Kuriki M Lindgren R Liu TJ Lombard-Nelsen RM Marroncle J Maruyama T Maruyama XK McCarthy J Meyer W 《Physical review letters》1996,76(4):587-591
13.
The polarized 3He program of Hall A at Jefferson Lab will be described. Results on the generalized Gerasimov-Drell-Hearn integral for the neutron in a Q2 range between 0.02 GeV2/c2 < Q2 < 0.9 GeV2/c2 will be presented. Preliminary results of the virtual photon asymmetry A1n(x, Q2) and the spin structure function g2n(x, Q2) at large values of Bjorken x and low Q2, respectively, will be discussed.Received: 1 November 2002, Published online: 15 July 2003PACS:
11.55.Hx Sum rules - 13.40.Gp Electromagnetic form factors - 13.88.+e Polarization in interactions and scattering - 29.25.Pj Polarized and other targets 相似文献
14.
Cross-section measurement for the ~(93)Nb(n,2n)~(92g)Nb reaction at the neutron energy of 14.6 MeV by the AMS method 下载免费PDF全文
The cross-section for the~(93)Nb(n,2n)~(92g)Nb reaction has been measured at the neutron energy of 14.6 Me V using neutron activation and accelerator mass spectrometry(AMS)determination of the long-lived product nuclide~(92g)Nb.The neutron energy was generated from the D+T neutron source at the China Institute of Atomic Energy(CIAE).The neutron flux was monitored by measuring the activity of~(92m)Nb produced in the competing reaction channel of~(93)Nb(n,2n)~(92m)Nb.At the neutron energy of 14.6 MeV,the~(93)Nb(n,2n)~(92g)Nb reaction cross-section of(736±220)mb was obtained for the first time. 相似文献
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Solvignon P Liyanage N Chen JP Choi S Aniol K Averett T Boeglin W Camsonne A Cates GD Chang CC Chudakov E Craver B Cusanno F Deur A Dutta D Ent R Feuerbach R Frullani S Gao H Garibaldi F Gilman R Glashausser C Gorbenko V Hansen O Higinbotham DW Ibrahim H Jiang X Jones M Kelleher A Kelly J Keppel C Kim W Korsch W Kramer K Kumbartzki G Lerose JJ Lindgren R Ma B Margaziotis DJ Markowitz P McCormick K Meziani ZE Michaels R Moffit B Monaghan P Munoz Camacho C Paschke K Reitz B Saha A Sheyor R 《Physical review letters》2008,101(18):182502
We present experimental results of the first high-precision test of quark-hadron duality in the spin-structure function g_{1} of the neutron and 3He using a polarized 3He target in the four-momentum-transfer-squared range from 0.7 to 4.0 (GeV/c);{2}. Global duality is observed for the spin-structure function g_{1} down to at least Q;{2}=1.8 (GeV/c);{2} in both targets. We have also formed the photon-nucleon asymmetry A1 in the resonance region for 3He and found no strong Q2 dependence above 2.2 (GeV/c);{2}. 相似文献
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D. Allasia C. Angelini A. Baldini L. Bertanza A. Bigi V. Bisi F. Bobisut T. Bolognese A. Borg E. Calimani P. Capiluppi R. Casali S. Ciampolillo R. Cirio J. Derkaoui M. L. Faccini-Turluer V. Flaminio A. G. Frodesen D. Gamba G. Giacomelli H. Huzita B. Iongejans I. Lippi M. Loreti C. Louedec G. Mandrioli A. Margiotta A. Marzari-Chiesa A. Nappi R. Pazzi L. Riccati A. Romero A. M. Rossi A. Sconza P. Serra-Lugaresi A. Tenner G. W. van Apeldoorn P. van Dam N. van Eijndhoven D. Vignaud C. Visser R. Wigmans 《Zeitschrift fur Physik C Particles and Fields》1985,28(3):321-333
18.
N.G. Antoniou C. Chiou-Lahanas S.D.P. Vlassopulos E. Zevgolatakos 《Physics letters. [Part B]》1980,93(4):472-476
A particular j-plane singularity, leading to long-range effects in hadron scattering, is attributed to hard constituent quark interactions. A definite prediction for the nucleon structure function, including scaling violations consistent with QCD. is obtained, which is confronted with the available data. 相似文献
19.
D. Indumathi 《Zeitschrift fur Physik C Particles and Fields》1997,76(1):91-97
The recent high statistics NMC data on the Tin to Carbon structure function ratio seems to indicate, for the first time, a significant Q 2 dependence, especially at small values of Bjorken x, x < 0.05, and Q 2 > 1 GeV2. A purely log(Q 2)-type dependence of the structure functions, which is consistent with the free nucleon data, yields a fairly flat ratio with little or no Q 2 dependence. In view of this seeming contradiction, we re-examine the applicability of such a model to nuclear structure functions in such a kinematical regime. We find that the model is consistent with all data, within experimental errors, without any need for introducing additional Q 2 dependences or higher twist contributions. The model correctly reproduces the Q 2 dependence of the Carbon structure function as well. We also critically examine the Q 2 dependence of the corresponding spin dependent structure functions. 相似文献
20.
《Nuclear Physics B》1995,439(3):471-502
A measurement of the proton structure function F2(x, Q2) is reported for momentum transfers squared Q2 between 4.5 GeV2 and 1600 GeV2 and for Bjorken x between 1.8 × 10−14 and 0.13 using data collected by the HERA experiment H1 in 1993. It is observed that F2 increases significantly with decreasing x, confirming our previous measurement made with one tenth of the data available in this analysis. The Q2 dependence is approximately logarithmic over the full kinematic range covered. The subsample of deep inelastic events with a large pseudo-rapidity gap in the hadronic energy flow close to the proton remnant is used to measure the “diffractive” contribution to F2. 相似文献