They refer to these auctions as "desperate deals," the defining feature of which is a price schedule that makes the government indifferent to default or repayment. The government randomizes at the time of repayment, which the authors show can be implemented in pure strategies by introducing stochastic political payoffs or external bailouts. Quantitatively, auctions at fire-sale prices are crucial for generating realistic spread volatility.
Self-Fulfilling Debt Crises, Revisited: The Art of the Desperate Deal
WP 17-07 - The authors revisit self-fulfilling rollover crises by introducing an alternative equilibrium selection that involves bond auctions at depressed but strictly positive equilibrium prices, a scenario in line with observed sovereign debt crises.