Hydrogen spectral series depend on the ground state $n_1$:

• Lyman Series ($n_1=1$): Transitions produce high-energy photons located in the Ultraviolet (UV) region.
• Balmer Series ($n_1=2$): Transitions produce photons in the Visible region.
• Paschen Series ($n_1=3$): Transitions produce photons in the Near-Infrared region.
• Brackett ($n_1=4$) and Pfund ($n_1=5$): Infrared region.