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Different physical processes in galaxy evolution, such as galaxy mergers thatlead to coalescence of dual Active Galactic Nuclei (AGN) and outflows emanatingfrom the narrow line region, can leave their imprint on the optical spectra ofAGN in the form of double-peaked narrow emission lines. To investigate theneutral gas in the centres of such AGN, we have conducted a pilot survey of HI21-cm absorption, using the upgraded Giant Metrewave Radio Telescope (uGMRT),in radio-loud AGN whose optical spectra show double-peaked [OIII] emissionlines at z<=0.4 (median z~0.14). Among the eight sources for which we couldobtain clean spectra, we detect HI 21-cm absorption in three sources (detectionrate of 38(+36/-20)%) and find tentative indication of absorption in two othersources. The detection rate of HI 21-cm absorption is tentatively higher forthe systems that show signatures of interaction or tidal disturbance (>~50%) inthe ground-based optical images than that for the systems that appear singleand undisturbed (~25%). This is consistent with the high incidence of HI 21-cmabsorption observed in z<=0.2 galaxy mergers. Higher spatial resolutionspectroscopy is required to confirm the origin of the HI absorbing gas, i.e.either gas infalling onto the radio-loud AGN, outflowing gas ejected by theAGN, or gas in rotation on the galactic-scale or circumnuclear discs.

HI 21-cm absorption in radio-loud AGN with double-peaked [OIII] emission