Heat sink and cooling apparatus

A heat sink for dissipating heat from an object, the heat sink having a center axis whereby a circumferential direction of the heat sink extends around the center axis and a radial direction of the heat sink extends normally to the center axis, the heat sink comprising:

• a plurality of fins spaced from one another about the center axis in the circumferential direction of the heat sink,
• each of the fins extending lengthwise in an outward direction away from the center axis whereby the fins radiate with respect to the center axis, wherein
• each of the fins has a stem at a radially inner end thereof and is split radially outwardly of the stem at each of at least two locations,
• at least two of said locations, at which each fin is split, are offset from one another along the length of each fin such that each fin has at a radially outer end thereof at least three outer fin end portions spaced from one another in the circumferential direction and such that each fin defines slits between adjacent ones of the outer fin end portions, and
• a radially innermost end of one of the slits is offset radially inwardly along the length of each fin from a radially innermost end of another of the slits.