YES it could be but it isn't.

It is very difficult to distinguish K⁰ from L because both may give "vee" :

K⁰ --> p⁺p^-

L--> pp^-

(For further information click here)

We have already co

mpared the positive track from the "vee" with the proton from the interaction. Because they have approximately the same momentum the lighter track will have the higher velocity, so it has the lower mass. 

To decide between K⁰ and lambda you have to look at the conservation of Q, B and S. But, to do that you have to answer the following question.

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