In this paper the differential cross sections for elastic and inelastic scattering 90-MeV -particle on Be for excited states at 2.43 MeV, 2.78 MeV, 5.59 MeV and 7.94 MeV in Be are analyzed. The purpose of these studies is to determine spin-parities of states which form the assumed third rotational band of the Be (2.78 MeV, 5.59 MeV 7.94 MeV), based on the existed state 2.78 MeV. In this paper we also use the data obtained earlier in an experiment on the + Be scattering at 30 MeV .
In the levels scheme  for excited states 2.78 MeV, 4.7 MeV, 5.59 MeV and 7.94 MeV in Be the following spin-parity values , , and have been given correspondingly. These values of spin-parities are considered to be generally accepted.
However, in 2015 an article  was published, in which new spin-parity values for the above-mentioned excited states were determined: = , , and respectively. They differ from generally accepted values . If this result is confirmed, it will revolutionize our understanding of the Be structure. The proposed new spin-parity value at 4.70 MeV excited state destroys the positive-parity rotational band, based on existed state 1.68 MeV, , by excluding one of its members as shown in . Changes in the spin-parity of the other levels question the existence of third rotational band, based on 2.78 MeV, .
Nevertheless, we are analyzing experimental data, obtained in experiments on + Be scattering induced by 30- and 90-MeV -particles in order to determine the spin-parity values of existed states that form the assumed third rotational band in the Be nuclei. The analysis is based on diffraction method MDM  and by comparing the behaviour of the obtained differential cross sections with differential cross sections at well studied states.
2.78 MeV and 7.94 MeV states in Be
In our research of 7.94 MeV state we have got the following results. On the fig.1 differential cross sections of inelastic + Be scattering induced by 90 MeV -particles at 2.43 MeV (red dots) and 7.94 MeV (black dots) in Be nucleus are shown in the dependence of momentum transfer q, as it allows us to show the diffraction part of differential cross section, necessary for the analysis, more clearly.
As we can see on the fig.1, the behaviour of the differential cross section at 7.94 MeV coincide with the curve, which comply with the diffraction mechanism, described by the squared Bessel function (blue curve), whose order is determined by the angular momentum transfer L. This shows that the value of spin-parity should be , i.e. remains generally accepted as shown in .
The additional factor in favor of keeping the generally accepted spin-parity value at 7.94 MeV is determined by comparison of the behaviour of differential cross section at 7.94 MeV with behaviour at well studied 2.43 MeV state, for which momentum transfer L = 2 and spin-parity equals is clearly established. This comparison shows that the position of extrema in diffraction part coincides.
Moreover, in article  the question of spin-parity values at 7.94 MeV has been raised. The authors have not confirmed the change of spin-parity value of this state, which corresponds to the saving of the value .
5.59 MeV state in Be
As for 5.59 MeV state, we have not got definite answer. The comparison of diffraction mechanism depending on squared Bessel function of 0 and 2 order with differential cross section at 5.59 MeV (fig.2) has been made.
From this comparison we could not determine which linear momentum transfer corresponds to this state. In case when L equals 0, the spin-parity value remains generally accepted as . However, if L equals 2, the spin-parity value will equal , as predicted in .
3.82 MeV state in Be
In article of R.Smith  the question of existent of a new state in Be nuclei at 3.82 MeV exited state has been arisen. This state was discovered with width = keV, one of the assumed spin-parity values at this state equaled . This value of spin-parity allows us to claim, that 3.82 MeV exited state may be the second member of assumed third rotational band.
The spectra, obtained from the experiment on + Be scattering induced by 30- and 90-MeV -particles, were analyzed. We could not identify this state from this experiment’s data at 90 MeV.
As for the data, obtained in the experiment on + Be scattering induced by 30-MeV -particles, the differential cross sections for this state have been acquired (fig.3).
However, differential cross section at 3.82 MeV state was close to the differential cross section of the background, as shown on fig.3. In this case we can not claim that this state can be seen. However, the question of existence of this state still remains open.
For the first time differential cross sections for inelastic + Be scattering induced by 90-MeV -particles were obtained for the following states in Be: 2.78 MeV, 5.59 MeV and 7.94 MeV.
The question of existence of the third rotational band, based on the 2.78 MeV, state, remains open. It has been shown that for the 5.59 MeV state the spin-parity value could be changed from to . The assumption was made that in case of changing spin-parity value at 5.59 MeV, the second member of the third rotational band may be the 3.82 MeV state with assumed spin-parity value .