Community Tip - You can change your system assigned username to something more personal in your community settings. X
i am also attaching a screenshot.
Soumyodeep, you can use the appkey to authenticate to access the mashup something like this :
http://ThingWorxServer>:<ThingWorxPort>/Thingworx/Mashups/<YourMashupName>?appKey=<YourAppKeyHere>&x-thingworx-session=true
You'll need to ensure that the appKey has enough rights to access that mashup