Hi @Megha Mauni ,
Actually it's not possible to disable the RSS feed for the ActivityStream on JIRA. Browsing Administration -> Add-Ons -> Manage Add-Ons -> System Plugins -> JIRA Activity Stream Plugin, there's no such module for disabling it. Although, it can be disabled for the issue navigator.
There's already an improvement request for disable the RSS on ActivityStream, but it's not implemented yet. You can follow it here:
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