E.L. Arch was a pseudonym used by Rachel Cosgrove Payes (1922?1998), an American author known for her work in science fiction, historical romance, and other genres. Born Rachel Cosgrove in Westernport, Maryland, she earned a degree in biology from West Virginia Wesleyan College and worked as a research biologist before turning to writing. She married Norman Morris Payes in 1954 and began her writing career in the 1950s.

Under the E.L. Arch pseudonym, she published science fiction novels, including The Man with Three Eyes (1967), The First Immortals (1965), Planet of Death (1964), and The Double-Minded Man (1966). These works often featured imaginative premises, such as alien conspiracies and futuristic settings, with The Man with Three Eyes centered on a bizarre alien espionage plot set in a diverse boardinghouse. Her science fiction was published primarily by Avalon Books, a publisher known for genre fiction.

Beyond science fiction, Cosgrove Payes wrote extensively under her own name and other pseudonyms, including Joanne Kaye and Rachel Payes. She penned numerous historical romance novels, mysteries and young adult fiction. Her bibliography includes over 40 novels, showcasing her versatility across genres. She also contributed short stories to magazines and worked as a freelance writer.

Cosgrove Payes was a trailblazer in genre fiction, balancing her scientific background with a flair for storytelling. She lived much of her life in the United States, raising a family while maintaining a prolific writing career. She passed away in 1998, leaving a legacy of diverse and engaging works.