[Hybrid baryons] Fwd: Proposal extension?

[Viktor Mokeev]

----- Forwarded Message -----
From: "Igor T. Obukhovsky" <obukh at nucl-th.sinp.msu.ru>
To: "Viktor Mokeev" <mokeev at jlab.org>
Cc: "valeri lyubovitskij" <valeri.lyubovitskij at uni-tuebingen.de>
Sent: Monday, May 16, 2016 7:32:56 AM
Subject: Re: Proposal extension?

Dear Victor,

we don't mind if you share our note with
your group.

About parity.
The hybrid ground state udsg
is of a positive parity (gluon ground state
in the bag is a color magnetic dipole with J^P=1^+).

In our note we used the name "uudg"
only as a shorthand notation for
the ground state in the udsg+K system (S-wave),
which should be of a negative parity.
Really it has a more complicated quark content,
uud(s\bar s)g.

I should like to discuss this more closely.
Really, in the qqqg system, there are two candidate on
the ground state, uudg and udsg.
We follow the "udsg version" and consider other
hybrids as excitations of udsg.

As I understand
you start from the uudg as a ground state,
and consider other hybrids as excitations of uudg.
The mass of uudg should be near 2.3 GeV.

However it is possible that the mass of uudg ground state (P=+)
is close to the mass of usdg+K state (P=-).
By the MIT bag evaluation made for usdg (1.8 GeV) it should be
near 2.3 GeV.

It is also possible that the MIT bag model underestimates
the udsg mass, while the flux tube model is more realistic.
But latter is also with problems: one could not use the
Pauli exclusion principle and the advantage of the udsg
state is decreased.

I thank you for your comments which are very useful for us.

With best regards,
                     Igor Obukhovsky.

On Sun, 15 May 2016, Viktor Mokeev wrote:


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