Hello Bharath,

In general, once an artifact is deleted - there's not a direct way to restore the artifact in your project. A project Snapshots/Baseline can be created for a particular point in time (even prior to the artifact being deleted).

You will want to select to 'Create a Baseline' for a date / time when you know the project data existed.
 
This forum post answers the question:
https://jazz.net/forum/questions/90044/rrc-4001-is-there-any-way-to-recover-the-artifact-which-got-deleted-accidentally
 
Here is infocenter information on creating baselines from projects:
http://www-01.ibm.com/support/knowledgecenter/SSYMRC_4.0.1/com.ibm.rational.rrm.help.doc/topics/c_snapshots.html
 
You can open the project baseline and copy/paste from it to a new artifact. So the process is manual and you do lose history of the original, deleted artifact.
 
There is an open request for enhancement "Add an undo, undelete for artifact deletion(s) or introduce persistence of deleted artifacts"

https://jazz.net/jazz03/web/projects/Requirements%20Management#action=com.ibm.team.workitem.viewWorkItem&id=73237

but it has not been delivered in the 4.0.x release.

Regards,

Ted