Observation of the Higgs Boson of strong interaction via Compton scattering by the nucleon
Martin Schumacher
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Zweites Physikalisches Institut der Universitt Gttingen
, Friedrich-Hund-Platz 1, 37077 Gttingen,
Germany
It is shown that the Quark-Level Linear Model (QLL M) leads to a prediction for the diamagnetic term of the polarizabilities of the nucleon which is in excellent agreement with experimental data. The bare mass of the meson is predicted to be m = 666 MeV and the twophoton width ( ) = (2.6 0.3) keV. It is argued that the mass predicted by the QLL M corresponds to the N N reaction, i.e. to a t -channel pole of the N N reaction. Large-angle Compton scattering experiments revealing effects of the meson in the differential cross section are discussed. Arguments are presented that these findings may be understood as an observation of the Higgs boson of the strong interaction while being a part of the constituent quark.
1 Introduction
The meson introduced by Schwinger [1] and Gell-Mann
Levy [2] has attracted great interest because there are good
reasons to consider it as the Higgs boson of strong
interaction, an aspect which recently has been emphasized by
several authors [36]. The mass of the meson is predicted
by the Quark-Level Linear Model (QLL M) [7, 8] (see
also [911] and references therein) to be m = 666 MeV,
whereas scattering analyses led to s = M i /2
with M = 441+16 MeV and = 544+1285 MeV in one
re8
cent evaluation (CCL) [12], or s = (476 628) i(226
346) MeV when tests of the stability of fits to data are taken
into account [13]. It certainly is extremely important to
understand how these two masses are related to each other.
The finding is that m = 666 MeV is the bare mass of the
meson which is observed in space-like Compton
scattering N N , i.e. as a t -channel pole of
Compton scattering N N . For the electromagnetic
polarizabilities space-like Compton scattering is equally important
as time-like Compton scattering N N (s-channel).
The and non- components of the electromagnetic
polarizabilities for the proton (p) and the neutron (n) are
p,n( ) = p,n = 7.6, p(non- ) = 4.4, p(non- ) =
9.5, n(non- ) = 5.8, n(non- ) = 9.4 in units of 104
fm3. On the quark level the reaction N N
implies that two photons with parallel planes of linear
polarization interact with mesons, being parts of the constituent
quarks. In this sense it is justified to consider space-like
Compton scattering as an in-situ observation of the Higgs
boson of strong interaction.
In addition to the specific aspects of the meson as
outlined in the preceding paragraph this particle is of interest
because it has been observed as an intermediate state in
many reactions [14]. Therefore, there is no doubt that this
particle exists and that it belongs to a scalar nonet ( (600),
f0(980), a0(980), (800)) below 1 GeV. A problem may
appear due to the fact that there is also a scalar nonet above
1 GeV. This has led to the assumption that the scalar nonet
above 1 GeV should be understood as qq states whereas the
scalar nonet below 1 GeV should be understood as qqq q
states (see e.g. [4] and references therein). Other versions
consider meson molecules and gluonic components (see [3
6, 1518] and references therein). It is hard to see that strict
criteria can be found giving proof of the validity of one
model and excluding the validity of an other. The best way
to proceed is to start with a model for the low-mass scalar
mesons where qq is a 3P0 core state which may couple to
other hadronic or gluonic configurations [17]. Then the
essential properties as e.g. the two-photon width ( )
may be understood in terms of the qq core whereas other
components may show up in hadronic reactions where scalar
mesons appear as intermediate states.
The present work is a continuation of a systematic series
of studies [9, 10, 1922] on the electromagnetic structure of
the nucleon, following experimental work on Compton
scattering and a comprehensive review on this topic [23]. These
recent investigations have shown [9, 10, 1922] that a
systematic study of all partial resonant and nonresonant
photoexcitation processes of the nucleon and of their relevance for
the fundamental structure constants of the nucleon as there
are the electric polarizability (), the magnetic
polarizability () and the backward spin-polarizability ( ) is
essential for an understanding of the electromagnetic structure of
the nucleon. In addition it has been found that the structure
of the constituent quarks and their coupling to pseudoscalar
and scalar mesons is important for the understanding of the
electric and magnetic polarizabilities and of the backward
spin-polarizability. The main purpose of the present work is
to prove that the method of calculating the t -channel
contribution from the reaction N N where the
properties of the meson are taken from the QLL M is a
precise procedure and largely superior to previous approaches
where the combination of the two reactions
and N N is exploited.
2 The dynamical (...truncated)