Systematics of geometric scaling
نویسندگان
چکیده
منابع مشابه
Geometric scaling and QCD evolution
We study the impact of the QCD DGLAP evolution on the geometric scaling of the gluon distributions which is expected to hold at small x within the saturation models. To this aim we solve the DGLAP evolution equations with the initial conditions provided along the critical line Q2 = Qs(x) with Q 2 s(x) ∼ x and satisfying geometric scaling. Both fixed and running coupling cases are studied. We sh...
متن کاملSome Remarks on Geometric Scaling *
is the so-called saturation scale. This scale is related to the mean transverse momentum of the partons inside the proton. Its growth with 1/x stems from gluon recombination (for a review, see [2]). The fact that geometric scaling holds is often considered a hint for saturation effects in deep-inelastic scattering. Our first remark concerns a point that has not been much commented so far: the a...
متن کاملGeometric Scaling and QCD Dynamics in DIS
DIS data from HERA show a striking regularity as σγ p is a function of the ratio τ = Q/Qs(x) only. The scaling function shows a break at τ ≈ 1, which has been taken as an indication for saturation. However, besides saturation also the transition between dominance of k⊥-ordered (DGLAP) and k⊥-non-ordered (BFKL) evolution contributes to a break around this value of τ , as well as the suppression ...
متن کاملGeometric Scaling above the Saturation Scale
We show that the evolution equations in QCD predict geometric scaling for quark and gluon distribution functions in a large kinematical window, which extends above the saturation scale up to momenta Q of order 100 GeV. For Q < Q s , with Qs the saturation momentum, this is the scaling predicted by the Colour Glass Condensate and by phenomenological saturation models. For 1 <∼ ln(Q/Qs) ≪ ln(Q2s/...
متن کاملGeometric Scaling in a Symmetric Saturation Model∗
We illustrate geometric scaling for the photon-proton cross section with a very simple saturation model. We describe the proton structure function F2 at small-x in a wide kinematical range with an elementary functional form and a small number of free parameters. We speculate that the symmetry between low and high Q2 recently discovered in the data could be related to a well-known symmetry of th...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physics Letters B
سال: 2007
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2007.01.055