Physics Letters B 781 (2018) 155–160
Contents lists available at ScienceDirect
Physics Letters B
www.elsevier.com/locate/physletb
CGC/saturation approach: Soft interaction at the LHC energies
E. Gotsman
a,∗
, E. Levin
a,b
, I. Potashnikova
b
a
Department of Particle Physics, School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Science, Tel Aviv University, Tel Aviv, 69978, Israel
b
Departemento de Física, Universidad Técnica Federico Santa María, and Centro Científico-Tecnológico de Valparaíso, Avda. Espana 1680, Casilla 110-V,
Valparaíso, Chile
a r t i c l e i n f o a b s t r a c t
Article history:
Received
21 December 2017
Received
in revised form 13 March 2018
Accepted
25 March 2018
Available
online 29 March 2018
Editor:
A. Ringwald
Keywords:
BFKL
Pomeron
Soft
interaction
CGC/saturation
approach
Pomeron
structure
In this paper we demonstrate that our model which is based on the CGC/saturation approach, is able to
describe the soft interaction collisions including the new TOTEM preliminary data at 13 TeV. We believe
that this strengthens the argument that the CGC/saturation approach is the only viable candidate for an
effective theory for high energy QCD.
© 2018 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license
(http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP
3
.
1. Introduction
In our recent paper [1]we have constructed a model, which
allows us to discuss soft and hard processes on the same footing, it
is based on the CGC/saturation approach (see Ref. [2]for a review)
and on our previous attempts to build such a model [3–10].
In
the model which we proposed in Ref. [1], we successfully
describe the DIS data from HERA, the total, inelastic, elastic and
diffractive cross sections, the t-dependence of these cross sections,
as well as the inclusive production and rapidity and angular corre-
lations
in a wide range of energies, including that of the LHC.
Since
the main feature, that we discuss in Ref. [1], are the an-
gular
correlations, our progress in describing the soft interaction
data went unnoticed. The representatives of the TOTEM collab-
oration,
reporting on their new preliminary results for energies
W = 2.76 TeV [39] and W = 13 TeV [11], neglected to mention
our model as one that provides a good description of their data
(see Ref. [11]).
The
goal of this letter is to draw the attention of the high en-
ergy
community that our approach is successful in describing the
entire set of data for high energy soft scattering, including the new
experimental data from the LHC.
*
Corresponding author.
E-mail
addresses: gotsman @post .tau .ac .il (E. Gotsman), leving @post .tau .ac .il,
eugeny.levin @usm .cl (E. Levin), irina .potashnikova @usm .cl (I. Potashnikova).
2. The model: theoretical input from the CGC/saturation
approach
Our model incorporates two ingredients: the achievements of
the CGC/saturation approach and the pure phenomenological treat-
ment
of the long distance non-perturbative physics, necessary, due
to the lack of the theoretical understanding of confinement of
quark and gluons.
For
completeness of presentation we initially include a review
of our approach, more details of which can be found in [1].
For
the effective theory for QCD at high energies we have two
different formulations: the CGC/saturation approach [12–15], and
the BFKL Pomeron calculus [16–29]. In Ref. [28]it was shown, that
these two approaches are equivalent for
Y ≤
2
BFKL
ln
1
2
BFKL
(1)
where
BFKL
denotes the intercept of the BFKL Pomeron. In our
model
BFKL
≈ 0.2 −0.25 leading to Y
max
= 20 −30, which covers
all collider energies.
Bearing
this equivalence in mind, in constructing our model we
rely on the BFKL Pomeron calculus, as the relation to diffractive
physics and soft processes, is more transparent in this approach.
In
the framework of the BFKL Pomeron calculus we need
to solve two principle problems: to find the resulting (dressed)
Pomeron Green function and to specify the interaction of the
https://doi.org/10.1016/j.physletb.2018.03.069
0370-2693/
© 2018 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by
SCOAP
3
.