A New Narrow-Line Seyfert 1 galaxy : RXJ1236.9+2656

We report identification of a narrow-line Seyfert 1 galaxy RXJ1236.9+2656. X-ray emission from the NLS1 galaxy undergoes long-term variability with 0.1--2.0 keV flux changing by a factor of 2 within about 3 yr. The ROSAT PSPC spectrum of RXJ1236.9+2656 is well represented by a power-law of Gamma = 3.7 absorbed by matter in our own Galaxy (N_H = 1.33X10^20 cm**-2). Intrinsic soft X-ray luminosity of the NLS1 galaxy is estimated to be 1.5X10^43 erg/s in the energy band of 0.1-2.0 keV. The optical spectrum of RXJ1236.9+2656 is typical of NLS1 galaxies and shows narrow Balmer emission lines (1100 km/s < FWHM < 1700 km/s) of Hbeta, Halpha, and forbidden lines of [O III] and [N II]. Fe II multiplets, usually present in optical spectra of NLS1 galaxies, are also detected in RXJ1236.9+2656.