PKS 1413+135: OH and H I at <i>z</i> = 0.247 with MeerKAT

The BL Lac PKS 1413+135 was observed by the Large Survey Project "MeerKAT Absorption Line Survey" (MALS) in L-band, at 1139 MHz and 1293-1379 MHz, targeting HI OH lines absorption z = 0.24671. radio continuum is thought to come from a background object redshift lower than 0.5, as suggested absence of gravitational images. line detected high signal-to-noise, with narrow central component, red wing, confirming previous results. 1720 clearly (maser) emission, peaking velocity shifted -10 -15 km/s respect peak. 1612 lost due interferences. 1667 main tentatively absorption, but not 1665 one. Over 30 years, variability optical depths, rapid changes sight, caused superluminal motions knots. has varied 20 per cent depth, while OH-1720 depth factor 4. position widths also varied. absorbing galaxy an early-type spiral (maybe S0) seen edge-on, prominent dust lane, covering whole disk. Given measured mass concentration, size centimeter wavelengths (100 mas corresponding 400 pc 0.25), width nuclear regions are expected up 250 km/S. narrowness (< 15 km/s) suggest that comes outer gas ring, frequently S0 galaxies. millimetric even narrower 1 km/s), which corresponds restricted core. core source covered individual molecular clouds, column density few 10^22 cm-2, compatible screen X-rays.