Consider an interstellar spaceship.
It is a rather classical design, somewhat similar to the ISS Venture Star from Avatar:
Although it is not in tractor configuration.
The ship is very long and skinny. At the nose there is a thick, actively cooled radiation shield to protect from collisions with neutral interstellar hydrogen. After that there are the passangers in cryosleep, along with life support equipment and maintenance robots. Than come the very large fuel tanks and another thick shield. At the end there is an antimatter beamed core engine, putting out charged pions almost with c.
The plan is to accelerate with the help of lasers (in the home system) and a foldable photon sail, then accelerate further to 0.7c, and then coast a while, before flipping and starting to decelerate (to achieve orbit in a nearby star system.)
But there is a problem: the ship has to change it's orientation by 180 degrees to start deceleration. Inevitably it would travel sideways for some time, while having the highest relative velocity to the interstellar medium.
Assuming that it takes 5 minutes to rotate the ship, could the radiation hitting the unshielded side cause structural damage and/or harm the passangers?
Should additional shielding used on the cabin's side walls? Or would the minimalist shielding against galactic cosmic rays suffice for a short period of time?