Click on particles...

ParticleClicks.java

HashMap<UUID,Location> stands = new HashMap<UUID, Location>();
	
double particleHeight = 1.5;

public void onEnable() {
	getServer().getPluginManager().registerEvents(this, this);

    Bukkit.getScheduler().scheduleSyncRepeatingTask(this, new Runnable() {
        @Override
        public void run() {
            for(Location loc : stands.values()) {
                loc.getWorld().spigot().playEffect(loc, Effect.COLOURED_DUST, 0, 0, 0f, 0f, 0f, 30, 2, 64);
            }
        }
    }, 20L, 10L);
}

public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) {
	if(sender instanceof Player) {
        Player p = (Player) sender;

        ArmorStand as = (ArmorStand) p.getLocation().getWorld().spawnEntity(p.getLocation(), EntityType.ARMOR_STAND);
        as.setGravity(false);
        as.setVisible(false);
        stands.put(as.getUniqueId(), as.getLocation().add(0, particleHeight, 0));
	}
	return false;
}

@EventHandler
public void onStandClick(PlayerInteractAtEntityEvent event) {
    if(event.getRightClicked().getType() == EntityType.ARMOR_STAND && stands.containsKey(event.getRightClicked().getUniqueId())) {
        
        Location clicked = event.getRightClicked().getLocation().add(event.getClickedPosition());
        Location loc = event.getRightClicked().getLocation().add(0, particleHeight, 0);
        double distance = clicked.distance(loc);
        this.getLogger().info("Distance: " + distance);
        if (distance < 0.39) // max distance e.g. volume depends on the particle!
            event.getPlayer().sendMessage(ChatColor.GREEN + "[Particle] You clicked me!");
    }
}

The clicked position is a strange one... this is not really that usable as the distance to the particles point varies. Maybe there is a better entity for this job? Or could just use vectors properly.