Magnetic tape device and head tracking servo method

A head tracking servo method comprising:

• reading a servo pattern of a magnetic layer of a magnetic tape by a servo head in a magnetic tape device,
• wherein a magnetic tape transportation speed of the magnetic tape device is equal to or lower than 18 m/sec,
• the servo head is a magnetic head including a tunnel magnetoresistance effect type element as a servo pattern reading element,
• the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic hexagonal ferrite powder, non-magnetic powder, and a binding agent on the non-magnetic support,
• the magnetic layer includes the servo pattern, and
• a tilt cos θ of the ferromagnetic hexagonal ferrite powder with respect to a surface of the magnetic layer acquired by cross section observation performed by using a scanning transmission electron microscope is 0.85 to 0.95.