Denis Bayman McWhan beloved husband, father, grandfather, and accomplished scientist, passed away peacefully on May 2, 2025, at the age of 89, with his family by his side.

Born in Brooklyn, New York on Dec. 10, 1935, he spent his childhood in Morris Plains, New Jersey, the cherished son of Horace Bayman and Evelyn McWhan, who journeyed to the U.S. from England and Chile, respectively.  

In June of ‘59, he married his true love, Carolyn Quick McWhan of Worcester, Massachusetts. Together they built a life rich with adventure, curiosity, and family. Their early years took them to Berkeley, California, and then to Stockholm, Sweden, where Denis completed his post-doctoral work. Later they settled in Murray Hill, New Jersey, where they lovingly raised their three children.    

Denis was a pioneering experimental physicist whose career spanned more than four decades. After earning a B.S. in chemistry from Yale and a Ph.D. from the U.C. Berkeley, Denis often joked that he had “chosen the wrong field,” having ultimately made his mark in solid-state physics, not chemistry. He became known for his groundbreaking use of X-ray and neutron beams to explore the behavior of materials at the atomic level.  

His professional journey led him to the Royal Institute of Technology in Stockholm, the Centre National de la Recherche Scientifique in Grenoble, Bell Laboratories in Murray Hill, and Brookhaven National Laboratory. There, he chaired the National Synchrotron Light Source and served as associate laboratory director.   

Denis’ simple yet profound recipe for a fulfilling life: "Be curious about everything, work hard, and be in the right place at the right time."  Outside of the lab, he found joy in hands-on projects—building boats, restoring homes, and sharing his love of sailing, kayaking, tennis, and paddleball. He and Callie were avid travelers, but happiest sailing the Sheepscott River aboard Inching Along, their beloved Marshall catboat. Their Southport home became a haven of hospitality, welcoming friends, family, and visiting scientists from around the globe.  

Denis is survived by Callie, his wife of 66 years; three children and five grandchildren - Susan McWhan Tobin, her husband, David, and Patrick, Michael and Sarah Tobin, Jeanette Burney and her husband, Dennis, and David McWhan and his wife Patricia Toro, and children, Conner and Hannah McWhan. 

Denis will be remembered not only for his brilliance but also for his warmth, perseverance, and generous spirit.  A celebration of Denis’s life will be held at a later date.   

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