Assuming you have legitimate access to this image (via a Juniper support contract or archival backup), here is a typical deployment process on KVM (Linux) or EVE-NG.
What it likely is
If you rely on vMX 14.1 for production, you must create a migration plan. All vMX versions prior to 19.x are end of life. The recommended minimum today is Junos 21.x or 22.x (for which the image would be named something like jinstall-vmx-22.2R1.13-domestic.img). Jinstall-vmx-14.1r4.8-domestic.img