WASHINGTON — As the coronavirus outbreak enters a potentially dangerous new phase, with cases widening in Europe and expected to spread in the United States, economists have begun to raise their estimates for the risk of a global recession and fallout to the American economy.Economists say the stock market sell-off during the week reflects a reassessment of the likely magnitude of the hit to corporate earnings in the virus’s wake — suggesting the economic pain could last longer and the recovery may not be as swift as initially thought.“Businesses of all kinds, in a lot of places, being impaired really (made) me skeptical that this is something that would fade quickly and from which we would recover quickly,” said Carl Tannenbaum, chief economist at Northern Trust in Chicago.