What shape were the branches on the Menorah in the Beit Hamikdash? I have seen the diagram by the Rambam where he depicts it with angular branches. I am looking for sources in halacha (i.e. sources other than the Arch of Titus) for the rounded-branch version of the menorah.
There are two main opinions, one by Rashi saying that are straight lines going up at an angle, seen also in the Rambam on the Mishna and R' Abraham his son. See sources:
רש"י על התורה שמות כה, לב. והציור בפירוש המשנה לרמב"ם מנחות ג, ז. ודעת ר' אברהם בן הרמב"ם בדעת אביו. וכן כתב העזרת כהנים מידות ד, ז.
The other opinion is the Ibn Ezra, and it is the one accepted by Rav Ariel and the form used by Machon Ha'mikdash (דעת הראב"ע על התורה שמות כה, לב):
For more info look at their web site: see more here