Sec. 6.115. DEATH BENEFIT FOR RETIREE'S ESTATE. If a retiree dies and does not leave a beneficiary, the estate of the retiree is entitled to a death benefit payment from the fund in an amount equal to 10 times the amount of the annuity awarded by the board effective on the retiree's date of retirement, less any retirement or disability annuity and any lump sum under Section 5.015 of this Act paid to the retiree.