E+ P --> E+ X
[301.0]
Max results
Sort by Reverse order

Showing 3 of 3 results

Measurement of the Proton Structure Function $F_L$ at Low x

The H1 collaboration Aaron, F.D. ; Alexa, C. ; Andreev, V. ; et al.
Phys.Lett.B 665 (2008) 139-146, 2008.
Inspire Record 786161 DOI 10.17182/hepdata.45340

A first measurement is reported of the longitudinal proton structure function F_L(x,Q^2) at the ep collider HERA. It is based on inclusive deep inelastic e^+p scattering cross section measurements with a positron beam energy of 27.5 GeV and proton beam energies of 920, 575 and 460 GeV. Employing the energy dependence of the cross section, F_L is measured in a range of squared four-momentum transfers 12 < Q^2 < 90 GeV^2 and low Bjorken x 0.00024 < x < 0.0036. The F_L values agree with higher order QCD calculations based on parton densities obtained using cross section data previously measured at HERA.

9 data tables
Table 1

The measured longitudinal proton structure function FL at Q**2 = 12 GeV**2 extracted from the combined 920,575 and 450 GeV proton energy data.

Table 2

The measured longitudinal proton structure function FL at Q**2 = 15 GeV**2 extracted from the combined 920,575 and 450 GeV proton energy data.

Table 3

The measured longitudinal proton structure function FL at Q**2 = 20 GeV**2 extracted from the combined 920,575 and 450 GeV proton energy data.

More…

On the rise of the proton structure function F2 towards low x.

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Phys.Lett.B 520 (2001) 183-190, 2001.
Inspire Record 561805 DOI 10.17182/hepdata.46780

A measurement of the derivative (d ln F_2 / d lnx)_(Q^2)= -lambda(x,Q^2) of the proton structure function F_2 is presented in the low x domain of deeply inelastic positron-proton scattering. For 5*10^(-5)<=x<=0.01 and Q^2>=1.5 GeV^2, lambda(x,Q^2) is found to be independent of x and to increase linearly with ln(Q^2).

17 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Determination of the longitudinal proton structure function F(L)(x,Q**2) at low x.

The H1 collaboration Adloff, C. ; Aid, S. ; Anderson, M. ; et al.
Phys.Lett.B 393 (1997) 452-464, 1997.
Inspire Record 426362 DOI 10.17182/hepdata.44694

A measurement of the inclusive cross section for the deep-inelastic scattering of positrons off protons at HERA is presented at momentum transfers $8.5 \leq Q~2 \leq 35 GeV~2$ and large inelasticity $y = 0.7$, i.e. for the Bjorken-x range $0.00013 \leq x \leq 0.00055$. Using a next-to-leading order QCD fit to the structure function F_2 at lower y values, the contribution of F_2 to the measured cross section at high y is calculated and, by subtraction, the longitudinal structure function F_{L} is determined for the first time with an average value of $F_L=0.52 \pm 0.03 (stat)$~ {+0.25}_{-0.22}$ (syst) at $Q~2=15.4 GeV~2$ and $x=0.000243$.

3 data tables
Table 1

Inclusive cross section scaled by the kinematic factor K given by:. X*Q**4/((2*PI*ALPHA**2)*Y+). Y+=2(1-Y)+Y**2.

Table 2

F2 values corresponding to the cross section measurements. X*Q**4/((2*PI*ALPHA**2)*Y+). Y+=2(1-Y)+Y**2.

Table 3

Longitudinal structure function measurements.