F9.5V standards PecautMamajek16 estimate that G0V and G0/1V stars in the Houk/MSS catalogs correspond most closely to F9.5V on the modern grid (Gray MK types). Keenan80 standard: HD 176051 (=HR 7162) - F9.5V (the only F standard in Keenan80) Keenan88 standard: HD 114710 (=bet Com) - F9.5V Keenan89 standard: HD 114710 (=bet Com) - F9.5V (prim. stan.; but G0V elsewhere!) (B-V)(F9.5V) = 0.583 ; median SIMBAD F9.5V d<25pc (N=4) (B-V)(F9.5V) = 0.579 ; trend for standards, exemplars, xHIP d<25pc F9.5Vs for [Fe/H]=0.0 (B-V)(F9.5V) = 0.572 ; pri. stan. bet Com ([Fe/H] ~ +0.047) (B-V)(F9.5V) = 0.572 ; exemplar zet Tuc ([Fe/H] ~ -0.15) (B-V)(F9.5V) = 0.57 ; median CATSUP sample d<30pc (N=4) (B-V)(F9.5V) = 0.57 ; MorganAbt73/TableIII (B-V)(F9.5V) = 0.569 ; exemplar HD 100180 = HR 4437 ([Fe/H] ~ -0.01) (B-V)(F9.5V) = 0.56 ; Strassmeier00 halfway between F9V (0.55) and G0V (0.57) => adopt (B-V)(F9.5V) = 0.58 [adopted 10/25/2020] => adopt (U-B)(F9.5V) = 0.41 => adopt (Bt-Vt)(F9.5V) = 0.626 => adopt (V-Ic)(F9.5V) = 0.665 => adopt (V-Rc)(F9.5V) = 0.336 => adopt (Rc-Ic)(F9.5V) = 0.329 => adopt (V-J)(F9.5V) = 1.084 => adopt (V-H)(F9.5V) = 1.337 => adopt (V-Ks)(F9.5V) = 1.403 => adopt (H-Ks)(F9.5V) = 0.066 => adopt (J-H)(F9.5V) = 0.253 => adopt (V-Hp)(F9.5V) = -0.123 => adopt (W1-W2)(F9.5V) = -0.042 => adopt (W1-W3)(F9.5V) = -0.043 => adopt (W1-W4)(F9.5V) = -0.011 => adopt (G-J)(F9.5V) = 0.932 (need to check Gaia trends) => adopt (G-Ks)(F9.5V) = 1.251 (Bp-Rp)(F9.5V) = 0.771 ; color trend for B-V=0.58 (Bp-Rp)(F9.5V) = 0.814 ; Evans18 trend for V-I= 0.665 => adopt (Bp-Rp)(F9.5V) = 0.771 [updated 11/22/2020] (Bp-G)(F9.5V) = 0.339 ; color trend for B-V=0.58 => adopt (Bp-G)(F9.5V) = 0.339 [updated 11/22/2020] (G-Rp)(F9.5V) = 0.433 ; color trend for B-V=0.58 => adopt (G-Rp)(F9.5V) = 0.433 [updated 11/22/2020] (Ks-W1)(F9.5V) = 0.057 ; EEM trend for d<30pc for B-V=0.572 => adopt (Ks-W1)(F9.5V) = 0.057 [updated 12/29/2019] (G-V)(F9.5V) = -0.130 ; HD_7449_ F9.5V Gray06 HIP_5806_ (G-V)(F9.5V) = -0.132 ; HD_73121_ F9.5V Gray06 HIP_42123_ (G-V)(F9.5V) = -0.135 ; HD_30311_ F9.5V Gray06 HIP_22221_ (G-V)(F9.5V) = -0.144 ; HD_117378_ F9.5V+ Gray03 HIP_65775_ (G-V)(F9.5V) = -0.144 ; HD_44120_ F9.5V Gray06 HIP_29788_ (G-V)(F9.5V) = -0.147 ; HD_122862_ F9.5V Gray06 HIP_69090_ (G-V)(F9.5V) = -0.148 ; HD_23079_ F9.5V Gray06 HIP_17096_ (G-V)(F9.5V) = -0.148 ; HD_70889_ F9.5V Gray06 HIP_41134_ (G-V)(F9.5V) = -0.152 ; HD_38283_ F9.5V Gray06 HIP_26380_ (G-V)(F9.5V) = -0.153 ; HD_157338_ F9.5V Gray06 HIP_85158_ (G-V)(F9.5V) = -0.156 ; HD_20201_ F9.5V Gray06 HIP_14964_ (G-V)(F9.5V) = -0.158 ; HD_155826_ F9.5V Gray06 HIP_84425_ (G-V)(F9.5V) = -0.158 ; HD_1581_ F9.5V Gray06 HIP_1599_ (G-V)(F9.5V) = -0.159 ; HD_101177_ F9.5V Gray03 HIP_56809_ (G-V)(F9.5V) = -0.159 ; HD_186651_ F9.5V Gray06 HIP_97370_ (G-V)(F9.5V) = -0.161 ; HD_65907_ F9.5V Gray06 HIP_38908_ (G-V)(F9.5V) = -0.171 ; HD_117105_ F9.5V Gray06 HIP_65737_ (G-V)(F9.5V) = -0.175 ; HD_200525_ F9.5V Gray06 HIP_104440_ (G-V)(F9.5V) = -0.195 ; HD_214953_ F9.5V Gray06 HIP_112117_ => adopt (G-V)(F9.5V) = -0.155 [updated 10/30/2020] (g-r)(F9.5V) = 0.410 ; Jordi06 (V-R)=>(g-r) for V-R=0.323 (g-r)(F9.5V) = 0.391 ; Bilir05 (B-V)=>(g-r) for B-V=0.572 (g-r)(F9.5V) = 0.375 ; Covey07 => adopt (g-r)(F9.5V) = 0.39 [updated 10/10/2020] Teff(F9.5V) = 5932 K ; exemplar zet Tuc ([Fe/H] ~ -0.21; see below) Teff(F9.5V) = 5986 K ; Teff from smoothed SpT(Teff) trend Teff(F9.5V) = 5989 K ; exemplar HD 100180 Teff(F9.5V) = 5995 K ; Gray03/06 F9.5Vs median from TIC9/Stassun19 Teff(F9.5V) = 5996 K ; pri. stan. bet Com ([Fe/H] ~ +0.06; see below) Teff(F9.5V) = 6001 K ; interp F8V(B-V=0.53,T=6180K), G0V(B-V=0.60,T=5930K) => adopt Teff(F9.5V) = 5990 K (logTeff = 3.777) [updated 10/25/2020] BCv(F9.5V) = -0.033 ; Balona94 calib for Teff=5990K, set so BCv(5772K)=-0.085 BCv(F9.5V) = -0.035 ; Bertone04 calib for Teff=5990K, set so BCv(5772K)=-0.085 BCv(F9.5V) = -0.050 ; Flower96 calib for Teff=5990K, set so BCv(5772K)=-0.085 BCv(F9.5V) = -0.056 ; Masana06 calib for Teff=5990K, set so BCv(5772K)=-0.085 BCv(F9.5V) = -0.058 ; Casagrande18 calib for Teff=5990K, set so BCv(5772K)=-0.085 BCv(F9.5V) = -0.058 ; Casagrande08 calib for Teff=5990K, set so BCv(5772K)=-0.085 BCv(F9.5V) = -0.059 ; Bessell98 calib for Teff=5990K, set so BCv(5772K)=-0.085 BCv(F9.5V) = -0.061 ; Code76 calib for Teff=5990K, set so BCv(5772K)=-0.085 => adopt BCv(F9.5V) = -0.06 [last updated 8/31/2019; adjusted so that BCv(5772K)=-0.085] Mv(F9.5V) = 4.29 ; linear fit to Gray01/03/06 dwarf sequence (d<50pc) for B-V=0.572 Mv(F9.5V) = 4.30 ; Gray01/03/06 dwarfs, xHIP B-V/Mv, Gaspar16 |[Fe/H]|<0.05 "solar": fit for B-V=0.572 Mv(F9.5V) = 4.31 ; F dwarf trend standards/exemplars Mv(F9.5V) = 4.34 ; Wright04 Mv(B-V = 0.58) Mv(F9.5V) = 4.39 ; xHIP |[Fe/H]|<0.2 dex d<25pc dwarf only for B-V=0.58 Mv(F9.5V) = 4.41 ; EEM d<25pc trend for B-V=0.58 Mv(F9.5V) = 4.43 ; pri. stan. HD 114710 = bet Com ([Fe/H] ~ +0.047) Mv(F9.5V) = 4.46 ; median SIMBAD F9.5V d<25pc (N=4) => adopt Mv(F9.5V) = 4.35 mag [updated 10/30/2020] => adopt M_G(F9.5V) = 4.195 mag [updated 12/10/2020] (Mv=4.35, G-V=-0.155) => adopt M_Ks(F9.5V) = 2.947 mag [updated 12/30/2020] (Mv=4.35, V-Ks=1.403) logL(F9.5V) = 0.180 ; Mv=4.35, BCv=-0.06 => Mbol=4.29 => adopt logL(F9.5V) = 0.180 [last updated 10/30/2020] => adopt Mbol(F9.5V) = 4.290 [last updated 10/30/2020] Mass(F9.5V) = 1.201 Msun ; EEM Teff vs. Mass calibration (Teff=5990K) Mass(F9.5V) = 1.140 Msun ; HenryMcCarthy93 calibration for Mv=4.4 Mass(F9.5V) = 1.091 Msun ; EEM logL vs Mass calibration (logL=0.16) Mass(F9.5V) = 1.083 Msun ; Eker18 logL vs. Mass calibration (logL=0.16) Mass(F9.5V) = 1.078 Msun ; EEM calibration to Torres10 EBs (Mv=4.4) Mass(F9.5V) = 1.053 Msun ; Bertelli09 solar tracks (Teff=5990,logL=0.16) => adopt Mass(F9.5V) = 1.08 Msun [updated 12/29/2019] Rad(F9.5V) = 1.194 Rsun ; Gray03/06 F9.5Vs median from TIC9/Stassun19 Rad(F9.5V) = 1.186 Rsun ; Stassun/TICv8 Rads for smoothed trend for Gray03/06 FVs (Teff=5990K) Rad(F9.5V) = 1.1423 Rsun ; logL=0.180, Teff=5990K => adopt Rad(F9.5V) = 1.142 Rsun [last updated 10/30/2020] # Primary Standard HD 114710 = bet Com = HR 4983 = GJ 502 F8/9V: 1979RA......9..479C F9V: Morgan38,Keenan38,Keenan41,Latham91 *F9.5V : KeenanYorka85,Keenan89(prim.stan.) G0V : Maury1897(G0IV/V),Adams35,MK43,JM53,Barry70(G0Vb),Morgan71,MK73,Cowley76(stan),Bidelman85,GrayAtlas,Gray01 G2V : 1957ArA.....2...55O,Houk(changed,but she doesn't recommend use as a standard) Appears to be a common G0V standard among Morgan, Keenan & Gray, but not Houk. But Houk acknowledges that her late Fs and early Gs might be earlier than that for the MK73 system. "F9.5V" primary standard according to Keenan89, but "G0V" elsewhere. Note that very few references actually quoted F9.5V types before about 1980, and the MK43 grid didn't even have a F9V let alone a F9.5V, so we should be surpised at these +-0.5 subtype shifts by Keenan in the 1980s. For 18 published types, mean is F9.6+-0.1 (stdev +-0.5). The colors and Teff appear to be very representative for a ~solar composition star intermediate between F9V and G0V, so I adopt this as primary F9.5V standard following Keenan89. V=4.23(HIP), B-V=0.572+-0.006(HIP), V-I=0.67+-0.04(HIP). PASTEL averages (Soubiran22): Teff=5996+-17K(N=40), logg=4.42+-0.02(N=24), [Fe/H]=+0.06+-0.01(N=30). plx = 108.8951+-0.3487 mas (GaiaDR2), plx = 109.54+-0.17mas(vanLeeuwen07). Mv = 4.43. # Deprecated Standard HD 176051 = HR 7162 *F9V: Keenan85,Keenan89,Gray01 F9.5V: Keenan80 G0V: Adams35,Roman52(weak lines),Harlan74,Abt81,Bidelman85(G0),Cannon(G0) It's a 1" binary, and the SpT floats in the literature. Not a great standard. Keenan85 listed it as "the" F9V standard, but just a few years after classifying it as F9.5V. # Exemplar zet Tuc = HD 1581 = HR 77 (V=4.2; J0020-6452) F9V: Malaroda75 *F9.5V: Gray06 G0V: Hoffleit37,Woods55,Houk75,Gray89 G2V: Evans57 V=4.228+-0.009(Mermilliod91), B-V=0.572+-0.006(Mermilliod91), U-B=0.018+-0.007(Mermilliod91). PASTEL averages (Soubiran22): Teff=5932+-12K(N=23), logg=4.43+-0.03(N=20), [Fe/H]=-0.21+-0.01(N=20). HD 100180 = HR 4437 = HIP 56242 F7V: Adams35 F9: Bidelman85 *F9.5V: Gray03 G0V: Harlan70 G0IV: Abt84 Nearly equal brightness binary WDS J11317+1422 (0.2" sep, mag=7.0, 7.1). Photometry for unresolved pair. B-V=0.569+-0.001(Mermilliod91), U-B=0.070(Mermilliod91), V=6.270+-0.070(Mermilliod91), V=6.27(HIP), Ks=4.904+-0.016(2MASS), V-Ks=1.366(Mermilliod91,2MASS). PASTEL: 4 Teffs, 1 very poor. One very good set of estimates, from Valenti05: Teff=5989+-44K, logg=4.38+-0.06, [Fe/H]=-0.01+-0.03. plx = 42.2619+-0.0812 mas (GaiaDR2). Mv = 4.40 (but for unresolved pair). # Other Stars iot Per = HD 19373 = HR 937 = Cl Melotte 20 44 F9.5V: Adams38,Gray03 *G0V: 1937ApJ....85..380M,MK43,Heckman56(G0),1961UppAn...4j...1L,Keenan80,Keenan89(stan) G0IV-V: Gray01 G1V: Adams35,1956AN....283..109H,Bidelman85(G1) G2V: Moore50 Continuity in use by Keenan from MK43 through Keenan89, and Gray keeps at same subtype. B-V=0.595+-0.007(Mermilliod91), U-B=0.118+-0.010(Mermilliod91), V=4.049+-0.007(Mermilliod91). PASTEL median parameters: Teff = 5953+-12K, [Fe/H] = 0.08+-0.02, logg = 4.22+-0.03. ### xHIP F9.5V d<25 pc (all are Gray03/06 types) HIP SpT [Fe/H] eFe/H B-V eB-V 1599 F9.5V -0.16 0.01 0.576 0.010 14632 F9.5V 0.08 0.01 0.595 0.007 38908 F9.5V -0.28 0.01 0.573 0.009 56242 F9.5V -0.06 0.02 0.570 0.000 56809 F9.5V -0.20 0.01 0.566 0.007 89805 F9.5V 0.05 0.08 0.584 0.004 104440 F9.5V -0.07 0.08 0.586 0.005 <=(B-V: TYC replacing HIP) 112117 F9.5V 0.03 9.99 0.584 0.003 and including the standards & interlopers: bet_Com F9.5V 0.047 _ 0.572 _ zet_Tuc F9.5V -0.15 _ 0.576 _ HD100180 F9.5V -0.01 _ 0.569 _ removing the color outlier HIP 104440, and retaining only those within 0.2 dex of solar, the color-metallicity trend is: B-V = 0.5789 + 0.05849*[Fe/H] (rms = 0.008 mag)