Events are not stored in the transaction or on the blockchain itself. Instead, they are stored on the receipt of the transaction. This receipt is stored in the node's receipt tree, which is a special data structure in the blockchain.
Solidity recordsare also a part of this data structure.
These records cannot be accessed through smart contracts, but they provide valuable information about what happens in transactions and blocks. It is precisely because of their inaccessibility to smart contracts that makes them cheaper to issue.