If its already parting company, there may be an inherant weakness in the bow - is there any way you can return it to the manufacturer?
Next option would depend upon where the split is and how far it has extended - if it is in a non-moving/non-flexing area, you could try any two-pack epoxy.
If the split is in a part of the bow that flexes (in a limb), the glue that was popular a few years ago was "Cascamite" a powdered resin - you mix however much you need with water and spread it into the split and clamp tightly to squeeze any excess glue out, which you trim off after it has dried. It might be easier to get into the split if you can get a small hypodermic syringe and needle to inject the glue deep into the split.
The repaired area will never be quite as strong as the original bow - so it will be important to address the reason why it began to fail in the first place.If it was subjected to abnormal damage, you might get away with the repair. If the split was caused by "over-drawing", the split is likey to reappear in short order.
It's a tall order to get it back to its original performance, but should be worth at least trying.
ATB
Ogri the trog
Oh, and welcome to the forum!