yeah couldn't find a clip that went further, I know the scene you are talking about. I used the word obliterate as a follow on from "vaporize" used in the op. Fragmented could be used I suppose, or ruptured, or destroyed etc ad nauseam....
Alderaan was indeed obliterated. It wasn't vapourised. It was also demolished, even disintegrated. Note that disintegrated does not necessarily mean totally destroyed and rendered into nothingness, as we see in a phaser blast. It also mean "made not integral" which would include shattered. Since the Death Star's beam did not impart significant (in astronimic terms) velocity to most of the debris, gravitational forces would indeed coalesce it into a clump, but not for millions of years. For the forseeable future, it's an asteroid cluster. Not necessarily an asteroid BELT, as that would mean the asteroids would be spread out in their solar orbit. Ain't picking SF apart fun?!?
or a visual of a small section of The Graveyard (the asteroid field left in the aftermath of Alderaan was named the Graveyard).
As per wookipedia "The incident resulted in the complete annihilation of Alderaan and the death of all its inhabitants."
Here is a ruff explanation of how I was going to explain the Super Laser at one time.
The Super Weapon Is Capable Of Vaporizing Ships As Large As A Romulan Warbird Is A Single Shot. The Enhanced Shields Are No Effect Against The Super Weapon. The Prolonged Use Of The Weapon Against A Planet Can Cause The Planet Of Explode Naturally.
Most Of The planets Surface Material is Unrefined ores and Have 0 – 2 Resistance and Deeper To The Core Has The Average Resistance Increases Up To 4 Till It Reached A Depth Of One Sixth Of The Diameter Of The Planet and Then The Resistance Drops To Zero. The Death Star Super Weapon Fired At Maximum Causes The Beam To Drill Down To The Center Of The Planet and Detonate The Planets Core. Due To The Beams Width I Figured That The Beam Was No More Than A 10 to 100 Meters Across and The 2166 Kilometers Stand Between The Surface and The One-Sixth Distance To The Upper Core Area. With 1 Su’s Per Kilometer The Weapon. The Death Star Takes Two Round Of Fire To Destroy A Planet With The First Round Firing and Cutting To Depth and The Second Causing The Core To Heat Up Creating An Explosion From Inside. The Other Version Is That The Super Laser Fires At Overload Strength Of 9000 Leaving 336 To Heat The Subsurface Material To Explosive Levels. Of Course This Would Be Different For Different Sized Planets A Planet With A Diameter Of 8000 Kilometers Would Have A Crust Of 1333 Kilometers and A Single Shot Could Destroy The Planet. On The Other Hand A Planet 19500 Kilometer Diameter Would Have A Crust Of 3250 Kilometers and Would Require Three Rounds Of Continuous Fire To Destroy. This Is The Figures That I Came Up With To Detail The Game A Little.