We meet ordinary human beings who are somehow adrift or groping for resolution or connection in the short story collection, “In the Event of Contact,” the third from Ethel Rohan, who is also the author of the well-received 2017 novel, “The Weight of Him.” These deft, character-driven tales are delivered in prose that is spare but sharp, steely and shot through with uncannily apt imagery that occasionally registers with delicious little shocks of recognition for the reader.