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We report on the identification of a new $\gamma$-ray-emitting narrow-lineSeyfert 1 (NLS1) galaxy, SDSS J1.55+041315.7, which increases the numberof known objects of this remarkable but rare type of active galactic nuclei(AGN) to seven. Its optical spectrum, obtained in the Sloan Digital SkySurvey-Baryon Oscillation Spectroscopic Survey, reveals a broad H $\beta$emission line with a width (FWHM) of 1734$\pm$104 km s$^{-1}$. This, along withstrong optical Fe II multiplets [$R_{4570}=0.9$] and a weak [O III] $\lambda5007$ emission line, makes the object a typical NLS1. On the other hand, thesource exhibits a high radio brightness temperature, rapid infraredvariability, and a flat X-ray spectrum extending up to $\sim$200 keV. It isassociated with a luminous $\gamma$-ray source detected significantly with {\itFermi}/LAT. Correlated variability with other wavebands has not yet beentested. The spectral energy distribution can be well modelled by a one-zoneleptonic jet model. This new member is by far the most distant$\gamma$-ray-emitting NLS1, at a redshift of $z=0.966$.

Identification of a New $\gamma$-ray-emitting narrow-line Seyfert 1 Galaxy, at Redshift $\sim1$