What is this java_pid%pid_number%.hprof and can it be deleted

I have my ES data and ES Logs going to another location, but in my /var/lib/elasticsearch I have a file named java_pid%pid_number%.hprof that has cause my OS drive to be out of space. which is now causing me issues. What is this and can i delete it?

A hprof is a heap dump, which happens if the JVM has an OOM issue.
You can delete it if you want, but it's probably worth digging into.