Reduce the opacity (see manual on transparency panel)

hero jig,

You should be aware that treating the individual rays as independent objects, like the highlighted one, cut out from the sun will result in an angular (and irregular because they are unevely spaced) inner disc part.

If you want to have the rays evenly spaced, and semi transparent round a possibly (more) opaque disc with a rounded border between them, you may start over using one ray:

0) Start with the first ray at the top,

1) Create a circle the size of the (inner) disc, placed so that it covers/coincides with the bottom ends of the path forming the ray,

2) Rotate the ray from 0) round the centre of the circle 1) (select the former and click the latter) 12 times by an angle of 360/13,

3) Create a copy of the circle 2) and select that along with the rays 2) and Pathfinder>Minus Front/Subtract from shape area (in earlier versions where you may need to press Alt/Option to Expand).

With that, you will have 13 evenly spaces rays and 1 central disc as separate objects with a cicular border in between.

You may group the rays if created as separate objects, and you  may change the stacking order of rays and disc in the Layers palette/panel.

If you want to keep the uneven spacing, you may skip 2) and part of 3) and just create the circle on top of the rays and then copy and use the Pathfinder option.

hero jig,

You may do it in at least two ways:

Especially if the HUM is live Type and you wish to keep it that way, you may change its colour from grey to white, select both HUM and disc and in the Transparency palette flyout tick Make Opacity Mask, untick Clip and keep Invert Mask ticked.

If the HUM is live Type, Type>Create Outlines, select both HUM and disc and Pathfinder>Minus Front (in older versions, Pathfinder>Subtract form shape area, in older versions among the older hold Alt/Option to Expand).

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