Multiwavelength Properties of Radio-loud Narrow-Line Seyfert 1 Galaxies

Radio-loud Narrow-line Seyfert 1 (NLS1) galaxies are important new laboratories
for studying the mechanism of radio-jet formation at high accretion rates and low black hole
masses, in a regime very different from classical blazars. Their strong thermal and non-thermal
spectral components shed new light on the jet-disk connection, through spectral and
SED modelling, while the gamma-ray detection severeal radio-loud NLS1s informs us about the
emission processes of gamma-rays in the central engine of low-mass AGN.
While NLS1 galaxies have been studied thoroughly at optical and X-ray energies
for decades, the populations of radio-loud, and gamma-ray emitting NLS1 galaxies
have only emerged recently. This talk provides a review of the optical and high-energy
properties of this intriguing class of AGN, including implications for NLS1 models, large-scale
ionized gas outflows, and multi-wavelength emission mechanisms.