A domain is being quarantined for 30 days as it has either expired or been set to be deleted. During this period none of the Internet services (e.g. website, e-mail) linked to the quarantined domain name, is functional.
RGP status will tell you the precise state a domain is in. If RGP is set to Redemption Period, it means domain was set to be deleted. If there is no RGP status, domain has expired.