You could sue for assault but it doesn't sound like the injury warrants the time and expense of a lawsuit.
The above answer, and any follow up comments or emails is for informational purposes only and not meant as legal advice.
Dear Brooklyn Tenant:
An assault by a superintendent upon a tenant, may be found as a breach of the warranty of habitability, especially if the landlord has or should have knowledge or an awareness of the superintendent's violent nature, as a violent or abusive superintendent, is equivalent to a failure by the landlord to provide reasonable security to tenants from the commission of a crime.
The warranty of habitability does not require a tenant to rely upon expert testimony to establish the diminished rental value of the rented premises, but some proof or evidence of diminished rental value is required, even if only provided by the tenant. An assault even when committed by an employee of the landlord is more likely to result in a determination of damages if launched as a claim for personal injuries.
The answer provided to you is in the nature of general information. The general proposition being that you should try to avoid a bad outcome if you can.
If you want to sue the super for the attack you need to find a personal injury attorney who will take the case on terms that are financially satisfactory to you. It may be that the cost of the lawsuit will be more than it is worth but you will not know that until you try talking to various personal injury attorneys. You should discuss with those attorneys the possibility of also suing your landlord and/or management company as the super's employer Please bear in mind that a lawsuit brought against an individual for attacking you must be brought within one year of the incident or it is barred
In some states this may be considered attorney advertising. This answer is provided as general information and is not legal advice.