Can I get ECMTicket with OAUTH authentication mode

[darbha]

I am using ADF Core 3.7.0, and enabled OAUTH authentication to work with ACS and APS. While intergrating ARender viewer, I needed to pass ECMTicket against the parameter "alf_ticket", whereas I am getting OAuth token from AuthenticationService. How do I get the ECMTicket value. 

private authService: AuthenticationService
....

alfTicket = this.authService.getTicketEcm();

When I am using "OAUTH" as "authType", I am not getting this ECM Ticket. But, I am getting the OAUTH token value via.

this.authService.getToken();

 Is there a way I can get ECMTicket using this token. Please suggest.