Could you please help me??

I draw this diagram from a phonetic book/British pronuciation But the symbols which were underlined by yellow color ,I do not think that they are phonetic symbols because we have only
/æ / as in cat
/ʌ / as in cut
/ɜ: / as in turn

And we have not ɑ and ɜ
Also the/ ɜ/ / ɔ/ should be with colon
So I am very confused