This mode is the same as the mixolydian mode, but it has one alteration to it, which is the minor 6th that is added. You could also respell the minor 6th as an augmented 5th.
By stacking 3rds above the root, we get a list of dominant chords that are formed:
1-3-5= Major Triad
1-3-5-b7= Dominant 7th
1-3-5-b7-9= Dominant 9th
1-3-5-b7-9-11= Dominant 11th
1-3-5-b7-9-11-b13= Dominant 11b13
If the b6 is respelled as the #5, other chords emerge:
1-3-#5= Augmented Triad
1-3-#5-b7= Augmented 7
1-3-#5-b7-9= Augmented 9
If this mode is played over unaltered dominants, the minor 6th will be a strong tension tone. But if this is played over a altered dominant which has a #5 in it, this tone will be used as a character pitch and not be so tense sounding.
This vamp uses 2 types of dominant chords: an altered one and an unaltered one. On the unaltered one, the minor 6th will be a good tone to resolve.
Vamp #1:(A7#5/A9(C#m7b5)) (Use A Mixolydian b6. All black dots on A)