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Thermal gas in the center of galaxy clusters can show substantial motionsthat generate surface-brightness and temperature discontinuities known as coldfronts. The motions may be triggered by minor or off-axis mergers that preservethe cool core of the system. The dynamics of the thermal gas can also generateradio emission from the intra-cluster medium (ICM) and impact the evolution ofclusters' radio sources. We aim to study the central region of Abell 1775, asystem in an ambiguous dynamical state at $z=0.072$ which is known to host anextended head-tail radio galaxy, with the goal of investigating the connectionbetween thermal and nonthermal components in its center. We made use of a deep(100 ks) Chandra observation accompanied by LOFAR 144 MHz, GMRT 235 MHz and 610MHz, and VLA 1.4 GHz radio data. We find a spiral-like pattern in the X-raysurface brightness that is mirrored in the temperature and pseudo-entropy maps.Additionally, we characterize an arc-shaped cold front in the ICM. We interpretthese features in the context of a slingshot gas tail scenario. The structureof the head-tail radio galaxy "breaks" at the position of the cold front,showing an extension that is detected only at low frequencies, likely due toits steep and curved spectrum. We speculate that particle reacceleration isoccurring in the outer region of this tail, which in total covers a projectedsize of $\sim800$ kpc. We also report the discovery of revived fossil plasmawith ultra-steep spectrum radio emission in the cluster core together with acentral diffuse radio source that is bounded by the arc-shaped cold front. Theresults reported in this work demonstrate the interplay between thermal andnonthermal components in the cluster center and the presence of ongoingparticle reacceleration in the ICM on different scales.

Nonthermal phenomena in the center of Abell 1775: An 800 kpc head-tail, revived fossil plasma and slingshot radio halo