Low adiabat dynamics is necessary for efficient compression and achievement of ignition conditions in a laser fusion targets. In this case, any additional sources of target interior heating are undesirable. Parametric laser-plasma instabilities can lead to the generation of a noticeable amount of hot electrons with energies of tens to hundreds of keV, that could penetrate into the target before the front shock arrives. The paper presents a hydrodynamics consistent model for generation and propagation of such electrons. Our simulations show that up to similar to 2 of the laser pulse energy can go into hot electrons with a temperature of about 100 keV, which appear as a result of the two-plasmon decay instability development. In this case, despite the relatively small part of absorbed by the target electrons (the value depends on the angular distribution of hot electrons and varies in the range of 3-15), a noticeable decrease in the neutron yield occurs. In a situation when parameters of plasma in the target are close to the ignition threshold, the effects associated with the generation of hot electrons can violate the ignition conditions.
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