F4V There is no F4V dagger HIP has 46 stars w/i 75 pc classified F4V, with (F4V) = 0.425 (HIP SpTs) Morgan65 classifed two Hyads as F4V or variant: HD 27561 (F4V) and HD 27901 (F4Vn). Gray01/03/06 lists 17 nearby F4V stars. Median colors: (F4V) = 0.412 (+-0.003 sem +-0.015 stdev; N=17) Gray01/03/06 (F4V) = 0.481 (+-0.005 sem +-0.019 stdev; N=17) Gray01/03/06 # No standard JM53, Morgan65, MK73, MorganAbt73, Cowley74, Cowley76, Keenan85, Corbally86, Gray89, GrayNstars do not list a F4V standard. Skiff08 did not flag any stars as F4V MK standards. Houk does not treat F4 as a full type, and does not list a standard. Houk lists one F4V star in her catalogs: HD 179512, however this star has no other published classifications in the Skiff MK catalog. It would appear that there are no generally agreed-upon F4V standard stars. Gray06 lists 14 F4V stars with Teff estimates. The stars with two median Teff estimates are HD 139664 (HIP 76829) and HD 77370 (HIP 44143). HD 77370 was listed as an F3V by both Houk75 and Gray89(!). HD 139664 has a range of published types (F2-F5). Morgan65 classified a few Hyades dwarfs as "F4V". His grid of fundamental standards had F3 and F6, but no intermediate standards. His F4V stars were: HD 27561 (=BD+14_687) and HD 27901 (BD+18_633). Gray01 calls HD 27561 a "F5IV-V", and most other authors consider the star F5 or F6 as well. HD 27901 is discussed later, but has been variously considered A9,F2, or F3. Neither star seem worthy of calling a standard given their range in published types. # A search for a suitable standard There is a noticeable lack of stars classified as F4V by multiple authors. Only four of the "pure" F4V stars from Gray et al. (2001,2003,2006) have been previously classified as F4V. None of these would seem to be worthy of calling a standard. HD 160032 at least has two Gray references with the same type. Note that Hyades F3Vs have B-V ~ 0.39, and F5Vs have B-V ~ 0.43-0.44. HD 27561 = (Hyad; one of Morgan's 2 F4V Hyads) F4V: Morgan65 F5V: Jaschek64,Jaschek78(Eggen50) F5IV-V: Treanor60,Gray01 F6V: Davis77 F6: Wilson48 F0: Cannon Unfortunately, only Morgan65 calls it F4V. B-V = 0.412 -- so it is intermediate between F3V and F5V Hyades. HD 27901 = HR 1385 = BD+18_633 (Hyad; one of Morgan's 2 F4V Hyads) F4V: Morgan65(F4Vn),Cowley74 F2IV-V: Treanor60 F2V: Abt95 A9V: Adams35 B-V = 0.378 -- similar to the F3Vs in Hyades HD 6397 = HR 308 F4V: Gray01(F4V((Sr))),Cowley76 F5V: Abt08 F4II-III: Harlan69,Hoffleit91 F0V: Wilson50 F2V: Adams35 HD 106103 = Cl Melotte 111 19 F4V: Gray01,Mendoza63,Trumpler38 F5V: Abt77,Westerlund56,Weaver52 F3V: Hill76 HD 160032 = HR 6569 = HIP 86486 F4V: Gray89,Gray06 F5V: Lu83 F3IV: Malaroda75 HD 220729 = HR 8907 = HIP 115713 F4V: Gray06,Malaroda75 F3IV: deVaucoleurs57 others without Gray et al. classifications, but maybe standard-worthy? HD 152303 = HR 6267 F4V: Cowley76,Cowley79,Wilson50 F5IV: Abt85 F1V: Joy35 HD 15138 = HR 709 = 66 And F4V: Cowley76,Abt69(F4V+F4V),Appenzeller67 F1V: Adams35 HD 17948 = HR 860 F4V: Wilson50,Appenzeller67,Cowley76,Cowley79 F6Va: Barry70(mw) hF6gF2mF2: Jaschek89 F5V: Gray03 looks like a good F4V standard, *but* Gray03 HD 157373 = HR 6467 F4V: Abt86(F4VmF2),Cowley79,Cowley76 F2V: Harlan74 F6V: Barry70(uv metals vw) HD 185395 = tet Cyg F4V: Abt85,Slettebak55,somebody38(error in Skiff catalog) F3+V: Gray03 F5IV: Roman50 F2V: Adams35