  The current manuscript deals with the tidal force effects, geodesic
deviation, and shadow constraints of the Schwarzschild-like black hole
theorised in Starobinsky-Bel-Robinson gravity exhibiting M-theory
compactification. In the current analysis, we explore the radial and angular
tidal force effects on a radially in-falling particle by the central black
hole, which is located in this spacetime. We also numerically solve the
geodesic deviation equation and study the variation of the geodesic separation
vector with the radial coordinate for two nearby geodesics using suitable
initial conditions. All the obtained results are tested for Sag A* and M87* by
constraining the value of the stringy gravity parameter $\beta$ using the
shadow data from the event horizon telescope observations. All the results are
compared with Schwarzschild black hole spacetime. In our study, we found that
both the radial and angular tidal forces experienced by a particle switch their
initial behaviour and turn compressive and stretching, respectively, before
reaching the event horizon. The geodesic deviation shows an oscillating trend
as well for the chosen initial condition. For the constrained value of $\beta$,
we see that the spacetime geometry generated by Sag A* and M87* is effectively
same for both Schwarzschild and Starobinsky-Bel-Robinson black hole.
Furthermore, we also calculated the angular diameter of the shadow in
Starobinsky-Bel-Robinson black hole and compared with the Schwarzschild black
hole. It is observed that the angular diameter of shadow for M87* and Sgr A* in
Starobinsky-Bel-Robinson black hole is smaller than the Schwarzschild black
hole. The calculated results satisfy the event horizon telescope observational
constraints. Finally, we have concluding remarks.
