### On Bessel property and unconditional basicity of the systems of root vector-functions of a Dirac type operator

#### Abstract

_{1}(x),y

_{2}(x))

^{T}, where B=(0 b

_{1}b

_{2}0

)

; b_{1} >0, b_{2} <0, P(x)=

(

p_{1}\(x) 0 0 p

_{2}(x)

)

, moreover p_{1} \(x) and p_{2} (x) are complex-valued functions determined on arbitrary finite interval G(a,b) by a real straightline, and establish the criterion of Bessel property and unconditional basicity of the system of root vector-functions of this operator.

#### Keywords

#### References

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