Radio frequency RF transmit coil for a magnetic resonance imaging system and magnetic resonance imaging system comprising the coil

A radio frequency transmit coil configured to transmit an RF field into a magnetic resonance examination zone of a magnetic resonance imaging system, the RF transmit coil comprising:

• an RF transmit antenna wherein the RF transmit antenna is formed by a plurality of rungs disposed along a central axis of the examination zone around a volume,
• a first end ring connected to a first end of the plurality of rungs,
• a second end ring connected to a second end of the plurality of rungs,
• wherein a layered capacitors structure is formed by the overlapping parts of the rungs and the first end ring and the second end ring,
• a carrier structure for separating the examination zone from the RF transmit coil, wherein the carrier structure is surrounded by the RF transmit antenna, wherein the carrier structure is made of a first material having a first dielectric permittivity, wherein
• at least one recess is foreseen in the carrier structure between the layered capacitors structure and the examination zone, wherein the recess extends fully circumferentially and partially axially over the axial extension of at least one of the first and second end rings along the carrier structure, wherein
• the recess is filled with at least a second material, so that the second material encircles the carrier structure as an extra layer, the second material having a second dielectric permittivity, wherein the second dielectric permittivity of the second material is higher as the first dielectric permittivity of the first material of the carrier structure.