M3.5V

Note that Rabus19 points out a discontinuity in the region
Teff=3200K-3340K where M dwarf radii 0.18 to 0.42 Rsun. M3.5V (Teff ~
3260K) is right in the middle of this region, and indeed there are
interferometric radii for M3.5Vs ranging from ~0.20 to ~0.37
Rsun. Mann15 fits a trend through the middle of the swarm, and I adopt
his [Fe/H] fit to guide the mean HRD point for M3.5V as function of
M_Ks.

Boeshaar76 standard:              GJ 251   - M3.5 (Plate II standard)
Boeshaar85 standard:              GJ 725B  - M3.5V (in Table II)
                                  GJ 251   - M3.5V (in text)
Kirkpatrick91 standards:          GJ 273   - M3.5V (primary standard)
	      			  GJ 725B  - M3.5V (primary standard)
				  GJ 669A  - M3.5V (secondary stan.)
				  GJ 748AB - M3.5V (secondary stan.)
				  GJ 643   - M3.5V (secondary stan.)
				  GJ 734B  - M3.5V (secondary stan.)
Kirkpatrick94 standards:	  GJ 725B (=HD 173740) - M3.5V
	      			  GJ 873 (BD+43_4305) - M3.5V
Henry02 standards: 		  GJ 15B   - M3.5V (cites Henry94)
				  GJ 105B  - M3.5V (cites Henry94)
				  G099-049 - M3.5V (cites Henry94)
				  LHS 1805 - M3.5V (cites Henry94)
				  GJ 273   - M3.5V (cites Kirkpatrick91)
				  GJ 300   - M3.5V (cites Henry94)
				  GJ 445   - M3.5V (cites Henry94)
				  GJ 555   - M3.5V (cites Henry94)
				  GJ 643   - M3.5V (cites Kirkpatrick91)
				  G203-47AB - M3.5VJ (cites Henry94)
				  GJ 725B  - M3.5V (cites Kirkpatrick91)
				  GJ 729   - M3.5V (cites Henry94)
				  GJ 829AB - M3.5VJ (cites Henry94)
				  GJ 873   - M3.5V (cites Henry94)
				  GJ 876   - M3.5VJ (cites Henry94)[but "J" because planet?]
				  GJ 896AC - M3.5VJ (cites Henry94)
GrayAtlas standard:               GJ 15B (=BD+43_44B) - M3.5V
Kirkpatrick(GrayCorbally09) stan: Gl 752B  - M3.5V (pri.)

Henry02 lists *12* M3.5V standards and 4 M3.5VJ standards. 
Three come from Kirkpatrick91 (GJ 273, 643, 725B).

RECONS lists shows GJ 729 (J1849-2350) as the nearest M3.5V star,
followed by GJ 725B (J1842+5937), GJ 15B (J0018+4401), & GJ 876A
(J2253-1415).

The eclipsing M3.5Ve+M3.5Ve binary CU Cnc has T = 3140 +- 150 K
(Ribas03).

(V-I)(M3.5V) = 2.65 ; Hawley96

<V-J>(M3.5V) = 4.17 (+-0.33 stdev) ; Lepine12

(V-Ks)(M3.5V)= 4.688 ; pri. stan. GJ 752B
(V-Ks)(M3.5V)= 4.81  ; deprecated stan. GJ 748AB
(V-Ks)(M3.5V)= 4.836 ; ter. stan. GJ 445
(V-K)(M3.5V) =  4.9   ; Hawley96
(V-K)(M3.5V) =  4.925 ; halfway between M3V(4.60) & M4V(5.25)
(V-Ks)(M3.5V)= 4.970 ; sec. stan. GJ 669A
(V-Ks)(M3.5V)= 4.975 ; deprecated stan. GJ 273
(V-Ks)(M3.5V)= 5.035 ; sec. stan. GJ 643
(V-Ks)(M3.5V)= 5.097 ; sec. stan. GJ 3378
(V-Ks)(M3.5V)= 5.125 ; ter. stan. GJ 729
(V-Ks)(M3.5V)= 5.17  ; exemplar GJ 876
(V-Ks)(M3.5V)= 5.407 ; ter. stan. GJ 555
=> adopt (V-Ks)(M3.5V) = 5.00  [updated 3/8/2018]

=> adopt (U-B)(M3.5V)  = 1.200
=> adopt (V-I)(M3.5V)  = 2.680
=> adopt (V-R)(M3.5V)  = 1.178
=> adopt (R-I)(M3.5V)  = 1.503
=> adopt (V-J)(M3.5V)  = 4.173
=> adopt (V-H)(M3.5V)  = 4.731
=> adopt (H-Ks)(M3.5V) = 0.269
=> adopt (J-H)(M3.5V)  = 0.558
=> adopt (G-V)(M3.5V)  = -1.266

(G-J)(M3.5V)   = 2.649 ; Bentley18/interp
(G-Ks)(M3.5V)  = 3.501 ; Bentley18/interp
(Ks-W2)(M3.5V) = 0.311 ; Bentley18/interp
(W1-W2)(M3.5V) = 0.156 ; Bentley18/interp

(Ks-W1)(M3.5V) = 0.140 ; Best18
(Ks-W1)(M3.5V) = 0.155 ; Bentley18/interp
(Ks-W1)(M3.5V) = 0.169 ; Avenhaus12 for V-Ks=5.00
(Ks-W1)(M3.5V) = 0.175 ; fit to Winters15 data for V-Ks=5.00
=> adopt (Ks-W1)(M3.5V) = 0.17 [updated 12/29/2019]


<B-V>(M3.5V) =  1.47 ; Fitzgerald70
(B-V)(M3.5V) = 1.556 ; sec. stan. GJ 669A
(B-V)(M3.5V) = 1.563 ; Koen10 median d<25pc M3.5V
(B-V)(M3.5V) = 1.588 ; pri. stan. GJ 725B
(B-V)(M3.5V) = 1.595 ; ter. stan. GJ 445
(B-V)(M3.5V) = 1.592 ; exemplar GJ 876 = LHS 530 
(B-V)(M3.5V) = 1.60  ; sec. stan. GJ 3378
(B-V)(M3.5V) = 1.623 ; ter. stan. GJ 555
(B-V)(M3.5V) = 1.676 ; sec. stan. GJ 643
(B-V)(M3.5V) = 1.740 ; ter. stan. GJ 729
=> adopt (B-V)(M3.5V) = 1.60 [updated 7/5/2020]

(Bp-Rp)(M3.5V)=   2.1731  ;  V*_GQ_And_    M3.5Ve
(Bp-Rp)(M3V)  =   2.50    ;  M3V mean
(Bp-Rp)(M3.5V)=   2.5466  ;  BD-05_5715_   M3.5V
(Bp-Rp)(M3.5V)=   2.5863  ;  L_205-128_    M3.5V
(Bp-Rp)(M3.5V)=  2.6280   ;  GJ_725B       pri. stan.
(Bp-Rp)(M3.5V)=   2.6564  ;  Wolf_1062_    M3.5V
(Bp-Rp)(M3.5V)=   2.6614  ;  G_48-20_      M3.5Ve
(Bp-Rp)(M3.5V)=   2.6677  ;  BD+19_5116A_  M3.5Ve
(Bp-Rp)(M3.5V)=   2.6726  ;  Ross_837_     M3.5V
(Bp-Rp)(M3.5V)=  2.6897   ;  GJ_669A       sec. stan.
(Bp-Rp)(M3.5V)=   2.7014  ;  V*_FL_Aqr_    M3.5V
(Bp-Rp)(M3.5V)=  2.7059   ;  GJ_445        ter. stan.
(Bp-Rp)(M3.5V)=   2.7155  ;  L_737-9_      M3.5V
(Bp-Rp)(M3.5V)=   2.7176  ;  CD-44_3045_   M3.5V
(Bp-Rp)(M3.5V)=   2.7625  ;  Wolf_437_     M3.5Ve
(Bp-Rp)(M3.5V)=  2.7835   ;  GJ_643        sec. stan.
(Bp-Rp)(M3.5V)=   2.7952  ;  G_111-47_     M3.5Ve
(Bp-Rp)(M3.5V)=  2.7975   ;  GJ_3378       sec. stan.
(Bp-Rp)(M3.5V)=   2.8154  ;  BD-15_6290_   M3.5V
(Bp-Rp)(M3.5V)=  2.8377   ;  GJ_729        ter. stan.
(Bp-Rp)(M3.5V)=   2.8437  ;  G_19-7_       M3.5Ve
(Bp-Rp)(M3.5V)=   2.8643  ;  V*_BX_Cet_    M3.5V
(Bp-Rp)(M3.5V)=   2.8799  ;  V*_V374_Peg_  M3.5Ve
(Bp-Rp)(M3.5V)=   2.8812  ;  G_203-47_     M3.5V
(Bp-Rp)(M3.5V)=   2.8873  ;  CD-44_11909_  M3.5
(Bp-Rp)(M3.5V)=   2.9055  ;  G_99-49_      M3.5Ve
(Bp-Rp)(M3.5V)=  2.9325   ;  GJ_555        ter. stan.
(Bp-Rp)(M4V)  =   2.95    ;  M4V mean
(Bp-Rp)(M3.5V)=   2.9537  ;  L_674-15_     M3.5V
(Bp-Rp)(M3.5V)=   2.9770  ;  G_36-24_      M3.5Ve
=> adopt (Bp-Rp)(M3.5V) = 2.78 [updated 11/18/2020]
Note: primary standard GJ 725B is somewhat bluer than most other M3.5V stars and standards


(G-Rp)(M3.5V)=   1.0340  ;  V*_GQ_And_    M3.5Ve
(G-Rp)(M3.5V)=   1.1389  ;  BD-05_5715_   M3.5V
(G-Rp)(M3.5V)=   1.1494  ;  L_205-128_    M3.5V
(G-Rp)(M3.5V)=   1.1620  ;  G_48-20_      M3.5Ve
(G-Rp)(M3.5V)=  1.1630   ;  GJ_725B       pri. stan.
(G-Rp)(M3.5V)=   1.1679  ;  V*_FL_Aqr_    M3.5V
(G-Rp)(M3.5V)=   1.1683  ;  Wolf_1062_    M3.5V
(G-Rp)(M3.5V)=  1.1698   ;  GJ_669A       sec. stan.
(G-Rp)(M3.5V)=   1.1702  ;  BD+19_5116A_  M3.5Ve
(G-Rp)(M3.5V)=   1.1715  ;  Ross_837_     M3.5V
(G-Rp)(M3.5V)=  1.1723   ;  GJ_445        ter. stan.
(G-Rp)(M3.5V)=   1.1879  ;  L_737-9_      M3.5V
(G-Rp)(M3.5V)= 1.190     ; color trend M0V-M9V 
(G-Rp)(M3.5V)=   1.1917  ;  Wolf_437_     M3.5Ve
(G-Rp)(M3.5V)=  1.1926   ;  GJ_643        sec. stan.
(G-Rp)(M3.5V)=  1.1973   ;  GJ_3378       sec. stan.
(G-Rp)(M3.5V)=   1.2004  ;  G_111-47_     M3.5Ve
(G-Rp)(M3.5V)=   1.2087  ;  G_19-7_       M3.5Ve
(G-Rp)(M3.5V)=   1.2095  ;  V*_BX_Cet_    M3.5V
(G-Rp)(M3.5V)=  1.2130   ;  GJ_729        ter. stan.
(G-Rp)(M3.5V)=   1.2135  ;  BD-15_6290_   M3.5V
(G-Rp)(M3.5V)=   1.2162  ;  V*_V374_Peg_  M3.5Ve
(G-Rp)(M3.5V)=  1.2172   ;  GJ_555        ter. stan.
(G-Rp)(M3.5V)=   1.2228  ;  G_99-49_      M3.5Ve
(G-Rp)(M3.5V)=   1.2264  ;  G_203-47_     M3.5V
(G-Rp)(M3.5V)=   1.2318  ;  L_674-15_     M3.5V
(G-Rp)(M3.5V)=   1.2342  ;  CD-44_11909_  M3.5
(G-Rp)(M3.5V)=   1.2471  ;  G_36-24_      M3.5Ve
(G-Rp)(M3.5V)=   1.2759  ;  CD-44_3045_   M3.5V
=> adopt (G-Rp)(M3.5V) = 1.19 [updated 11/18/2020]
=> adopt (Bp-G)(M3.5V) = 1.59 [updated 11/189/2019; Bp-Rp=2.78, G-Rp=1.19]

(Bp-G)(M3.5V) = 1.4650 ; GJ_725B  
(Bp-G)(M3.5V) = 1.5200 ; GJ_669A  
(Bp-G)(M3.5V) = 1.5336 ; GJ_445   
(Bp-G)(M3.5V) = 1.5909 ; GJ_643   
(Bp-G)(M3.5V) = 1.6003 ; GJ_3378  
(Bp-G)(M3.5V) = 1.6247 ; GJ_729   
(Bp-G)(M3.5V) = 1.7153 ; GJ_555

(G-V)(M3.5V) =  -1.4382 ; GJ_555 
(G-V)(M3.5V) =  -1.3691 ; GJ_729  
(G-V)(M3.5V) =  -1.3236 ; GJ_643
(G-V)(M3.5V) = -1.28   ; M3.5V SIMBAD d<20pc trend V-Ks vs. G-V for V-Ks=5.0
(G-V)(M3.5V) =  -1.2547 ; GJ_669A
(G-V)(M3.5V) =  -1.2498 ; GJ_445
(G-V)(M3.5V) =  -1.211  ; polynomial fit to SIMBAD d<25pc M dwarfs
(G-V)(M3.5V) =  -1.1664 ; GJ_725B
=> adopt (G-V)(M3.5V)  = -1.28 [updated 11/1/2020; M_G=10.87, Mv=12.15]
=> adopt (G-Ks)(M3.5V) = 5.00 + -1.28 = 3.72 [updated 7/17/2020]

(g-r)(M3.5V) = 1.47 ; Covey07 interp M3V 1.46, M4V 1.48

(r-i)(M3.5V) = 1.436 (+-0.05 rms) ; West05 fit for (V-Ic)=2.68

(i-z)(M3.5V) = 0.747 ; poly fit to d<75pc M dwarfs in SIMBAD for G-Ks=3.72

(z-J)(M3.5V) = 1.541 (+-0.028 rms) ; poly fit to d<100pc GCNS for G-Ks=3.72


Mv(M3.5V) =  11.07  ; sec. stan. GJ 699A
Mv(M3.5V) =  11.21  ; Koen10 d<25pc median M3.5V (note: limited by HIP)
Mv(M3.5V) =  11.75  ; EEM fit to Jao2016 Gaia data (V-Ks=5.00)
Mv(M3.5V) =  11.83  ; EEM fit to Reid CNS3 data (V-Ks=5.00)
Mv(M3.5V) =  12.00  ; pri. stan. GJ 725B
Mv(M3.5V) =  12.01  ; EEM fit to MS data(V-Ks=5.00)
Mv(M3.5V) =  12.05  ; Finch14(V-Ks=5.00)
Mv(M3.5V) =   12.05 ; Kirkpatrick94
Mv(M3.5V) =  12.08  ; EEM fit to Winters+2015 data (V-Ks=5.00)
Mv(M3.5V) = 12.10  ; M_Ks=7.10, V-Ks=5.00
Mv(M3.5V) =  12.19  ; Henry04(V-Ks=5.00)
Mv(M3.5V) =  12.20  ; Johnson09(V-Ks=5.00)
Mv(M3.5V) =  12.36  ; sec. stan. GJ 3368
Mv(M3.5V) =  12.43  ; ter. stan. GJ 555
Mv(M3.5V) =  12.62  ; ter. stan. GJ 634
Mv(M3.5V) =  13.15  ; ter. stan. GJ 729 
=> adopt Mv(M3.5V)   = 12.10 [updated 11/15/2021] (M_Ks=7.10, V-Ks=5.0)
=> adopt M_G(M3.5V)  = 10.82 [updated 11/15/2021] (Mv=12.10, G-V=-1.28)
=> adopt M_Ks(M3.5V) =  7.10 [updated 11/15/2021] (Mv=12.10, V-Ks=5.00]

M_G(M3.5V) =    8.95265 ; HD 152751                     
M_G(M3.5V) =   10.0547 ; BD+19 5116A                  
M_G(M3.5V) =   10.5257 ; BD-15 6290                    
M_G(M3.5V) =   10.558  ; Wolf 437
M_G(M3.5V) =   10.6946 ; BD+05 1668                    
M_G(M3.5V) =   10.7315 ; L 205-128
M_G(M3.5V) =  10.759  ; trend SIMBAD d<10pc sample
M_G(M3.5V) =   10.7875 ; HD 173740
M_G(M3.5V) = 10.82    ; Mv=12.10, G-V=-1.28
M_G(M3.5V) =   10.9011 ; BD-11 3759                   
M_G(M3.5V) =   11.0246 ; V* BX Cet                    
M_G(M3.5V) =   11.0719 ; CD-44 11909                   
M_G(M3.5V) =   11.0932 ; G 203-47                     
M_G(M3.5V) =   11.3143 ; G 99-49                       
M_G(M3.5V) =   11.3715 ; Wolf 629                     
M_G(M3.5V) =   11.7585 ; Ross 154                      
M_G(M3.5V) =   11.9189 ; V* GQ And


M_Ks(M3.5V)  =  6.10 ; sec. stan. GJ 699A
M_Ks(M3.5V)  =  6.75 ; EEM fit to Jao2016 (V-Ks=5.00)
M_Ks(M3.5V)  =  6.83 ; EEM fit to Reid CNS3 data (V-Ks=5.00)
M_Ks(M3.5V)  =  7.01 ; EEM fit to MS data(V-Ks=5.00)
M_Ks(M3.5V)  =  7.05 ; Finch14(V-Ks=5.00)
M_Ks(M3.5V)  =  7.08 ; EEM fit to Winters+2015(V-Ks=5.00)
M_Ks(M3.5V)  = 7.10  ; Mv=12.10, V-Ks=5.00
M_Ks(M3.5V)  =  7.19 ; Henry04(V-Ks=5.00)
M_Ks(M3.5V)  =  7.20 ; Johnson09(V-Ks=5.00)
M_Ks(M3.5V)  =  7.27 ; sec. stan. GJ 3378
M_Ks(M3.5V)  =  7.31 ; pri. stan. GJ 725B
M_Ks(M3.5V)  =  7.59 ; sec. stan. GJ 643
M_Ks(M3.5V)  =  8.03 ; ter. stan. GJ 729
[EEM: Note remarkable range of absolute magnitudes among *standards: 6.1 < M_Ks < 8.0!]


Teff(M3.5V) =   3391 K ; Passegger18 median Teff for CARMENES M3.5Vs(N=45)
Teff(M3.5V) =   3378 K ; Boyajian12 calibration for V-Ks=5.00
Teff(M3.5V) =   3320 +- 66 K ; Lepine12
Teff(M3.5V) =  3319 K ; sec. stan. GJ 669A
Teff(M3.5V) =   3317 K ; deprecated stan. GJ 273
Teff(M3.5V) =  3306 K ; Rajpurojit18 (mean for N=39 M3.5Vs)
Teff(M3.5V) =  3300 K ; sec. stan. GJ 3378
Teff(M3.5V) =  3300 K ; ter. stan. GJ 643
Teff(M3.5V) =   3300 K ; halfway between M3V(3400K) and M4V(3300K)
Teff(M3.5V) =  3280 K ; empirical L-R relation, for logL=-2.072
Teff(M3.5V) =  3280 K ; exemplar GJ 876 = LHS 530 
Teff(M3.5V) =  3290 K ; pri. stan. GJ 725B 
Teff(M3.5V) =   3280 K ; deprecated standard GJ 896AC (median Teff)
Teff(M3.5V) = 3270 K ; Rad=0.293Rsun for Mann15 calib for M_Ks=7.15, [Fe/H]=0.0
Teff(M3.5V) =  3253 K ; deprecated stan. GJ 273 (Rabus19 interferometry)
Teff(M3.5V) =  3240 K ; ter. stan. GJ 729
Teff(M3.5V) =  3218 K ; Morrell19 <Teff> for stars w/i +-0.05 mag of M_Ks=7.20
Teff(M3.5V) =   3200 K ; Rajpurohit13(N=8)
Teff(M3.5V) =  3200 K ; ter. stan. GJ 755 
Teff(M3.5V) =   3104 +- 28 K ; Boyajian12b (N=1)
=> adopt Teff(M3.5V) = 3270 K (logT = 3.515) [updated 7/17/2020]

BCv(M3.5V) = -2.101 +- 0.014 ; standard GJ 725B (Pecaut13)
BCv(M3.5V) = -2.225 ; Pecaut13(V-Ks=5.00)
BCv(M3.5V) = -2.228 ; deprecated stan. GJ 273 (below)
BCv(M3.5V) = -2.28  ; BC_Ks=2.72, V-Ks=5.00
BCv(M3.5V) = -2.283 ; Mann15(V-J=4.173)
BCv(M3.5V) = -2.334 ; ter. stan. GJ 729 (calc. using Rabus19)
BCv(M3.5V) = -2.375 ; exemplar GJ 876 (calc. using Rabus19)
=> adopt BCv(M3.5V) = -2.28 [updated 7/17/2020; BC_Ks=2.72, V-Ks=5.00]

BC_Ks(M3.5V) =  2.794 ; exemplar GJ 876 (calc. using Rabus19)
BC_Ks(M3.5V) = 2.791 ; ter. stan. GJ 729 (calc. using Rabus19)
BC_K(M3.5V)  = 2.775 ; Pecaut13(V-Ks=5.00)
BC_K(M3.5V)  = 2.734 ; Mann15(V-J=4.173)
BC_K(M3.5V)  = 2.72  ; LHS102A (Golimowski04)
BC_Ks(M3.5V) = 2.715 ; Morrell19 trend for G-Ks=3.71
BC_K(M3.5V)  =  2.587 +- 0.026 mag ; standard GJ 725B (Pecaut13) [mbol=7.587+-0.013, Ks=5.000+-0.023]
=> adopt BC_Ks(M3.5V) = 2.72 [updated 7/17/2020]


logL(M3.5V)  =  -1.72  ; sec. stan. GJ 669A(Newton15)
logL(M3.5V)  =  -2.033 ; pri. stan. GJ 752B(Newton15)
logL(M3.5V)  = -2.032 ; M_Ks=7.10, BC_Ks=2.72, Mbol=9.820
logL(M3.5V)  =  -2.076 ; Morrell19 trend for logL for M_Ks=7.20 
=> adopt logL(M3.5V) = -2.032 [updated 11/15/2021]
=> adopt Mbol(M3.5V) =  9.820 [updated 11/15/2021]

Mass(M3.5V)  =   0.17  Msun ; ter. stan. GJ 729
Mass(M3.5V)  =   0.179+-0.002 Msun ; GJ1005AB, pri. mass, unresolved M3.5V (Benedict16)
Mass(M3.5V)  =   0.25  Msun ; sec. stan. GJ 3378
Mass(M3.5V)  = 0.277 Msun ; Mann18 calib. for M_Ks=7.10
Mass(M3.5V)  =   0.277 Msun ; pri. stan. GJ725B (Mann15)
Mass(M3.5V)  =  0.291 Msun ; Benedict16 calibration for M_Ks=7.10
Mass(M3.5V)  =  0.302 Msun ; Eker18 calibration for logL=-2.032
Mass(M3.5V)  =   0.341 Msun ; exemplar GJ 876 (Mann15)
Mass(M3.5V)  =   0.379 Msun ; deprecated stan. GJ 748AB
Mass(M3.5V)  =  0.385 Msun ; Eker15 calibration for logL=-2.032
Mass(M3.5V)  =   0.433+-0.002 Msun ; GJ 2069A (Benedict16)
=> adopt Mass(M3.5V) = 0.28 Msun [updated 11/15/2021]

Rad(M3.5V)   =   0.205+-0.006 Rsun    ; ter. stan. GJ 729 (Rabus19)
Rad(M3.5V)   =  0.225 Rsun            ; Rabus19 trend for Teff=3280K [low trend]
Rad(M3.5V)   = 0.2999 Rsun           ; Mann15 trend M_Ks=7.10, [Fe/H]=0.0
Rad(M3.5V)   = 0.300 Rsun            ; Teff=3270K, logL=-2.032
Rad(M3.5V)   =  0.310+-0.013 Rsun     ; ter. stan. GJ 555 = HIP 71253 (Yee17)
Rad(M3.5V)   =  0.320 Rsun            ; Rabus19 trend for Teff=3280K [high trend]
Rad(M3.5V)   =   0.320+-0.005 Rsun    ; deprecated stan. GJ 273 (Rabus19)
Rad(M3.5V)   =   0.323+-0.006 Rsun    ; pri. stan. GJ 725B = LHS 59 (Yee17)
Rad(M3.5V)   =   0.3232+- 0.0061 Rsun ; Boyajian12b (N=1, presum. GJ 725B)
Rad(M3.5V)   =   0.328 Rsun           ; pri. stan. GJ 725B (Newton14)
Rad(M3.5V)   =   0.354+-0.005 Rsun    ; exemplar GJ 876 (Rabus19)
Rad(M3.5V)   =   0.373 Rsun           ; sec. stan. GJ 669A (Newton14)
=> adopt Rad(M3.5V) = 0.300 Rsun [updated 11/15/2021]

# Primary Standard

GJ 725B = LHS 59 = HD 173740 = HIP 91772 = Struve 2398B
 *M3.5V: Turnshek85,Boeshaar85(dM3.5),Kirkpatrick91(pri),Kirkpatrick94,Hawley97,Henry02,Geballe02,Kirkpatrick(GrayCorbally09)(pri),Dieterich12
  M4.5V: Joy74
  M4V: Wilson52,Newton14(near-IR)
  M5V: Adams26

  plx= 289.48+-3.21 mas(vanLeeuwen07),
  plx=283.8624+-0.1065mas(GaiaDR2). Teffs: 3395K(Soubiran08,Frasca09),
  3334+-66K(Gaidos14), 3345+-60K(Mann15), 3304K(Cenarro11),
  3295+-81K(Newton15#2), 3290K(Lepine13),
  3288K(Rojas-Ayala12,Frasca15), 3218+-12K(Pecaut13),
  3172K(Jenkins09), 3170+-71K(Valenti98), 3142+-29K(Newton15#1),
  3104+-28K(Boyajian12) => adopt 3290K. mbol=7.587+-0.013(Pecaut13),
  V=9.688+-0.006(Mermilliod91), J=5.721+-0.020(2MASS),
  H=5.197+-0.024(2MASS), Ks=5.00+-0.023(2MASS),
  B-V=1.588+0.006(Mermilliod91), B-V=1.59(Gliese91),
  B-V=1.561+-0.005(HIP), U-B=1.138+-0.010(Mermilliod91), V-Ks =
  4.688(Mermilliod91,2MASS). Mv=11.996+-0.025(HIP,vanLeeuwen07).
  M_Ks=7.308+-0.033(2MASS,vanLeeuwen07).  13.2" away from primary
  GJ725A. [Fe/H]=-0.92+-0.07(Valenti98), -0.38(Jenkins09),
  -0.30+-0.08(Mann15),
  -0.25+-0.12(Rojas-Ayala12). LogL=-2.0329+-0.0052(Newton15).
  Rad=0.281+-0.030 Rsun(Newton15), 0.273+-0.011 Rsun(Mann15).
  Mass=0.248+-0.025 Msun(Mann15). Companion is GJ 725A (HIP 91768).
  Note that the assignment of "A" and "B" is confused in some works,
  but the CNS3 Gliese91 catalog clearly identifies Gl 725 A as V=8.90
  "dM4" star, and Gl 725 B as a V=9.71 "dM5" star. Boyajian12 lists
  tetLD=0.851+-0.015mas. Boyajian12+HIP2=> Rad=0.322Rsun.

# Secondary Standards

GJ 669A = V647 Her = Ross 868 = StKM 2-1312 A = DO 15925 
 *M3.5V: Boeshaar85, Kirkpatrick91(sec),Hawley97,Lepine13
  M3: Stephenson86, Newton14(IR)
  M4Ve: Joy74,Stocke91,Houdebine12(dM4e)
  M5.0: Jenkins09

  plx=86.3+-3.1mas(Newton15), plx=86.27+-4.10mas(vanLeeuwen07).
  V=11.26(HIP, unresolved?), V=11.392+-0.033(Mermilliod91),
  V=11.340(Hartman11), B-V=1.556+-0.007(Mermilliod91),
  U-B=1.168+-0.017(Mermilliod91), J=7.273+-0.020, H=6.710+-0.031,
  Ks=6.422+-0.018(2MASS). V-Ks = 11.392-6.422 = 4.97. Mv=11.07+-0.09
  (using plx=86.3, V=11.392). M_Ks=6.10+-0.08. Teffs:
  3150+-50K(Houdebine12), 3260K(Lepine13), 3319+-100K(Houdebine16),
  3345+-63K(Muirhead18), 3423+-77K(Newton15) => median Teff =
  3319K. Radius: 0.373+-0.028Rsun(Newton15).
  logL=-1.72+-0.05dex(Newton15). [Fe/H]=0.31,0.34(Newton15).
  Companion is GJ 669B=V639 Her. Lepine13 appears to have the spectral
  parameters reversed for A and B? Very bright absolute magnitude for
  M3.5V, due to being very metal rich?
  
GJ 3378 = LHS 1805 = G 192-013 = NLTT 15885 = LSPM J0601+5935
 *M3.5V: Henry94,Hawley97(M3.5),Henry02,Kirkpatrick12,Dieterich12
  M3.7: Mann15
  M3.4: Shkolnik12
  M4.0: Newton14(near-IR,M4V),Gaidos14(M4),Lepine15

  V=11.71(vanAltena95), V=11.736+-0.083(Henden16),
  V=11.820+-0.089(Droege07), B-V=1.60(vanAltena95). plx=120.5+-5.6 mas
  (Finch16), 133.5+-2.5(Dittman14). J=7.465+-0.023(2MASS),
  H=6.949+-0.029(2MASS), Ks=6.639+-0.018(2MASS), V-Ks= 11.736-6.639 =
  5.097(Henden16,2MASS). Mv=12.36+-0.09
  (Henden16,Dittman14). Ms=7.266+-0.044(2MASS,Dittman14). Teffs:
  3178+-84K(Gaidos14), 3241K(Stelzer13), 3252+-83K(Newton15),
  3300K(Lepine15), 3300K(Rajpurohit18), 3323+-73K(Gaidos14),
  3340+-60K(Mann15#1), 3381+-26K(Mann15#2) => median Teff =
  3300K. [Fe/H]=-0.01 and 0.02 (Newton15), -0.09+-0.08(Mann15),
  [Fe/H]=-0.02, -0.14(Neves13). Radius: 0.261+-0.007Rsun(Mann15),
  0.269+-0.011 Rsun(Mann15). Mass: 0.245+-0.031 Msun(Newton15),
  0.245+-0.024 Msun(Newton15), 0.255(Jenkins09),
  0.255+-0.010Msun(Mann15) => mass = 0.25
  Msun. logL=-2.11+-0.06(Newton15).

GJ 643 = LHS 427 = Wolf 629 = 2MASS J16552527-0819207
 *M3.5V: Bidelman85,Kirkpatrick91(sec),Hawley97,Henry02,Geballe02,Reiners12
  M3V: Dieterich12,Gaidos14(M3),Newton14(near-IR)
  M4V: Walker83,Joy74, Houdebine12(dM4)
  M5: Vyssotzky56

  GJ 643 is the "C" component of a high order multiple (WDS
  16555-0820, LDS 573), possibly quintuple - indeed the main component
  of the system Wolf 630 is the eponym for Eggen's Wolf 630 Moving
  Group.  72" away from GJ 643 (LHS 427, HIP 82809) is the "primary"
  of the system: GJ 644 (LHS 428, HIP 82817; M2.5V, Henry02). GJ 644C
  (VB 8) is 299" away. Among the Washington Double Star components,
  components A, B, C, F appear to be physical, while D and E are
  probably background stars. plx = 148.92+-4.00mas(vanLeeuwen07).
  V=11.759+-0.0042(Landolt09), V=11.748(Koen10), V=11.77(Hosey15),
  B-V=1.672(Koen10), B-V=1.676+-0.0030(Landolt09), U-B=1.248(Koen10),
  U-B=1.256+-0.0034(Landolt09), V-Rc=1.179(Koen10),
  V-Rc=1.185+-0.0017(Landolt09), R-Ic=1.525+-0.0013(Landolt09),
  V-Ic=2.704(Koen10), V-Ic=2.715+-0.0013(Landolt09),
  Rc=10.55(Hosey15), Ic=9.01(Hosey15), J=7.555+-0.024(2MASS),
  H=7.056+-0.061(2MASS), Ks=6.724+-0.017(2MASS).  V-Ks = 11.759-6.724
  = 5.035+-0.018. Mv=12.624+-0.058 (from V=11.759, plx=148.92).
  M_Ks=7.589+-0.061 (from Ks=6.724, plx=148.92).  Teffs:
  3241K(Stelzer13), 3241K(Muirhead18), 3279+-64K(Gaidos14),
  3279+-60K(Mann15#1), 3300K(Rajpurohit18), 3305+-100K(Houdebine16),
  3339+-27K(Mann15#2), 3343K(Passegger18), 3376+-20K(RojasAyala12) =>
  adopt Teff=3300K.  [Fe/H]=-0.14+-0.11(Gaidos14),
  [Fe/H]=-0.13+-0.12(Newton14), [Fe/H]=-0.28(Neves13),
  [Fe/H]=-0.22+-0.17(RojasAyala12), [Fe/H]=-0.26+-0.08(Mann15).
  R=0.22+-0.06Rsun(Gaidos14),
  R=0.233+-0.011(Mann15). L=0.006+-0.004(Gaidos14),
  L=0.006(Bonfils13), M=0.19+-0.08Msun(Gaidos14),
  M=0.21+-0.02Msun(Neves13), M=0.21(Bonfils13),
  M=0.2040+-0.0200(Mann15).

# Tertiary Standard

GJ 555 = HN Lib = LHS 2945 = HIP 71253 = TYC 5572-804-1
 *M3.5V: Henry94,Henry02,Geballe02,Kirkpatrick12(Henry94),Neves13,Bonfils13
  M3: Bidelman85
  M4: Koen02, Koen10, Reiners12, Dieterich12, Stelzer13(M4.0), Newton14, Gaidos14, Mann15

  I list it as a tertiary standard as it was not in Kirkpatrick91 as
  either a primary or tertiary standard, but it does appear in Henry94
  and Henry02 as a standard.  Skiff07 compendium has no published SpTs
  before Henry's.  plx=164.99+-3.29mas(vanLeeuwen07). V=11.32(HIP),
  V=11.317(Koen10), V=11.346+-0.009(Mermilliod91), B-V=1.598(Koen10),
  B-V=1.623+-0.005(Mermilliod91), B-V=1.633+-0.052(HIP),
  V-Rs=1.224(Koen10), U-B=1.128+-0.045(Mermilliod91),
  V-Ic=2.844(Koen10), V-I=2.87+-0.05(HIP). J = 6.838+-0.019, H=
  6.262+-0.044,
  Ks=5.939+-0.034(2MASS). V-Ks=5.407(Mermilliod91,2MASS). Mv=12.433+-0.044(using
  V=11.346, plx=164.99). M_Ks = 7.026+-0.055(Ks=5.939,
  plx=164.99). Teff = 3066+-50K(Houdebine12), 3150K(Morales08),
  3165K(Stelzer13), 3211+-60K(Mann15), 3211+-68K(Gaidos14),
  3322+-32K(Mann15) => ~3200K. R=0.19Rsun(Gaidos14),
  Mass=0.14Msun(Gaidos14), [Fe/H]=0.38+-0.11 (Gaidos14). Mv =
  12.40+-0.04 (Koen10).

GJ 445 = LHS 2459 = G 254-029 = LTT 13235
 *M3.5V: Henry94,Hawley97,Henry02,Kirkpatrick12(Henry94)
  M4V: Luyten45(M4),Lee47(M4),Joy74,Lepine13(M4.0),Gaidos14(M4),Newton14(near-IR)
  M3: Bidelman85
  
  I list it as a tertiary standard as it was not in Kirkpatrick91 as
  either a primary or tertiary standard, but it does appear in Henry94
  and Henry02 as a
  standard. plx=186.86+-1.70(vanLeeuwen07). V=10.790+-0.010(Mermilliod91),
  B-V=1.595+-0.005(Mermilliod91), J=6.724+-0.024(2MASS),
  H=6.217+-0.044(2MASS), Ks=5.954+-0.027(2MASS), V-Ks = 10.790-5.954 =
  4.836+-0.029, J-K=0.770, J-H=0.507, H-Ks=0.263,
  mbol=8.482+-0.035(using Casagrande relation). Teffs:
  3158+-50K(Houdebine12), 3186+-60K(Gaidos14),
  3195+-38K(RojasAyalas12), 3240K(Morales08), 3241K(Stelzer13),
  3300K(Lepine13). R=0.19Rsun(Gaidos14), R=0.321Rsun(Houdebine12),
  L=0.003Lsun(Gaidos14), M=0.14Msun(Gaidos14),
  [Fe/H]=-0.35+-0.13(Newton14), [Fe/H]1=-0.25(Neves13),
  [Fe/H]2=-0.30(Neves13), [Fe/H]=-0.25+-0.17(RojasAyala12).

GJ 729 = Ross 154 = LHS 3414 = HIP 92403 = TYC 6859-1332-1 = V1216 Sgr = 2MASS J18494929-2350101
  M0: (1938AJ.....46..204O, "Cannon type").
  M3V: Stephenson86,Torres06(M3Ve)
  M3/4: Pesch65
 *M3.5V: Henry94,Hawley97,Henry02,Reid04,Riaz06
  M4: Bidelman85,Gaidos14
  M4.1: Mann15
  M4.5Ve: Joy74

  plx = 336.72+-2.03mas(vanLeeuwen07), 339.59+-1.63mas(Davison15).
  V=10.495+-0.111(Mermilliod91), V=10.495(Koen10), V=10.50(Hosey15),
  B-V=1.701+-0.044(Mermilliod91), B-V=1.740(Koen10),
  U-B=1.293(Koen10), V-Rc=1.217(Koen10), V-Ic=2.780(Koen10),
  Rc=9.26(Hosey15), Ic=7.68(Hosey15), J=6.222+-0.018(2MASS),
  H=5.655+-0.034(2MASS), Ks=5.370+-0.016(2MASS). V-Ks = 10.495-5.370 =
  5.125. Mv = 13.15+-0.01 (using plx=339.59, V=10.495), M_Ks =
  8.025+-0.019 (using plx=339.59, Ks=5.370). Teffs:
  3062+-50K(Houdebine12), 3162+-30K(Rabus19), 3213+-60K(Gaidos14),
  3240K(Morales08), 3240+-60K(Mann15), 3241K(Stelzer13),
  3252+-21K(Mann15#2) => adopt Teff=3240K.  R=0.19Rsun(Gaidos14),
  R=0.2008+-0.0076Rsun(Mann15), R=0.199+-0.003Rsun(Mann15).
  L=0.003Lsun(Gaidos14), L=0.004Lsun(Bonfils13). M=0.14Msun(Gaidos14),
  M=0.17+-0.01Msun(Neves13), M=0.17Msun(Bonfils13),
  M=0.181+-0.004Msun(Mann15) => <M>=0.17Msun.
  [Fe/H]1=-0.41(Jao15,Neves13), [Fe/H]2=-0.44(Neves12,Neves13),
  [Fe/H]=-0.10(Neves13), [Fe/H]=-0.18+-0.08(Mann15).  Rabus19:
  tetLD=0.642+-0.020mas, fbol=(1.370+-0.096)e-8 erg/s/cm2 (=> mbol =
  8.161+-0.076 IAU2015 scale), Rad=0.205+-0.006Rsun, Teff=3162+-30K.
  BCv = mbol - V = 8.161 - 10.495 = -2.334. BC_Ks = 8.161 - 5.370 =
  2.791.

# Exemplar

GJ 876 = LHS 530 = BD-15 6290 = G 156-57 = IL Aqr 
 *M3.5V: Walker83,Bidelman85,Henry94(M3.5VJ),Kirkpatrick94,Henry02,Lurie14
  M3.7: Mann15 
  M4V: Mukai90,Hawley97,Gaidos14,Schweitzer19(dM4.0)
  M4.5V: Joy74
  M5V: Vyssotsky52,Eggen65

  Deprecated standard, but retained as exemplar since it has has
  interferometric diameter (Rabus19) and is famous well-studied
  exoplanet host star. For some reason called "GJ 876A" although there
  does not seem to be a stellar "GJ 876B" (but there is planet "GJ
  876b").  V=10.179(Koen10), B-V=1.571(Koen10), U-B=1.168(Koen10),
  V-Rc=1.182(Koen10),
  V-Ic=2.733(Koen10). V-Ks=5.17(Hosey15). Ks=5.010+-0.021(2MASS). Rabus19:
  tetLD=0.705+-0.009mas, fbol=(1.902+-0.058)e-8 erg/s/cm2 (=> mbol =
  7.804+-0.033 IAU2015 scale), Rad=0.354+-0.005Rsun, Teff=3275+-18K.
  BCv = mbol - V = 7.804 - 10.179 = -2.375.  BC_Ks = mbol - Ks = 7.804
  - 5.010 = 2.794.  Mann15: fbol=(1.916+-0.015)e-11 W/m2 (=> mbol =
  7.797+-0.009).  Teffs: 3049+-92K(Hojjatpanah19), 3129+-19K(Yee17),
  3130K(Youngblood17), 3165K(Stelzer13), 3200K(Rajpurohit18),
  3235K(Newton15), 3247+-60K(Mann15), 3275+-18K(Rabus19),
  3283+-88K(Muirhead18), 3290+-10K(Mentuch08),
  3304+-100K(Houdebine16), 3317+-14K(Houdebine19), 3340K(Terrien15#3),
  3357K(Terrien15#1), 3359K(Passegger18),
  3377+-51K(Schweitzer19,Fuhrmesiter19), 3384+-32K(Mann15#2),
  3444K(Terrien15#2), 3935+-59K(Luck17) => <Teff> ~ 3280K.  [Fe/H] =
  0.17+-0.08(Mann15). Mass=0.341+-0.010Msun(Mann15).

# Deprecated Standards

GJ 873 = EV Lac = BD+43_4305
 *M3.5V: Bidelman85(M3.5),Kirkpatrick94(non-standard),Henry94,Hawley97,Henry02
  M4.5Ve: Joy74
  M4: Lee47 
  M5Ve: Adams26

  I deprecate this as a standard (although it appears in Henry94 and
  Henry02) as a standard as it is a very active BY Dra star and the
  colors appear to be significantly bluer than the other M3.5V
  standards (probably due to enhanced activity). Active, variable BY
  Dra "flare" star, with V magnitude between B = 8.28 and 11.83 (GCVS,
  Samus+2007-2013; also VSX). V=10.044+-0.052(Mermilliod91) for
  component 1, unresolved
  V=10.029+-0.042(Mermilliod91). B-V=1.412+-0.061(Mermilliod91) for
  component 1, unresolved B-V=1.374+-0.009(Mermilliod91).
  J=6.106+-0.030, H=5.554+-0.031, Ks=5.299+-0.024(2MASS).
  V-Ks=10.029-5.299 = 4.73.

GJ 748AB = Wolf 1062 = 2MASS J19121455+0253111 = HIP 94349
  M3: Bidelman85
 *M3.5V: Kirkpatrick91(sec.stan.),Hawley97,Tamazian06,Reiners12,Lepine13,Lurie14
  M4: Gliese69,Joy74,Gaidos14
  M5V: Arnaud89
  M0: Lee47

  Astrometric binary (Torres2010), 0.2" binary in WDS. Mag1=11.29,
  Mag2=13.11. Mass(A) = 0.379+-0.005, logL(A) =
  -1.78. V=11.143(Koen10), B-V=1.520(Koen10), U-B=1.0529(Koen10),
  V-Rc=1.127(Koen10), V-Ic=2.609(Koen10). V-Ks=4.81(Hosey15).  Plx =
  99.99+-1.22(Lurie14).

GJ 734B = HD 230017 B (V=13)
 *M3.5V: Kirkpatrick91(sec)

  3.5" fainter companion to V=9.4 M0V star (standard HD 230017 = V1436
  Aql).  Mermilliod91 photometry is for either blend or primary, and
  2MASS photometry is poor quality. Kirkpatrick type is only one in
  Skiff compilation (7/2015). There are plenty of other M3.5 standards
  with stronger pedigrees to choose from.

GJ 251 = HD 265866 = Wolf 294 = G 087-012 = LHS 1879 = HIP 33226
 *M3V: Lee47(M3),Kirkpatrick91(pri),Henry94,Hawley97,Henry02
  M3.5V: Joy74,Boeshaar76(stan),Boeshaar85(stan,in text)
  M4V: Stephenson86,Jenkins09
  M5: Roth51,Vyssotsky56

  Boeshaar76's M3.5V standard, but changed to M3V by Kirkpatrick,
  Henry, & Hawley.  B=11.609+-0.02(UCAC4), V=9.89(HIP),
  V=9.938(Hauck90), V=9.938+-0.063(Mermilliod91), V=10.01(Gliese91),
  V=10.02(Weis93), V=10.03(Reid02), V=10.034+-0.08(UCAC4),
  V=10.170+-0.08(Droege07) B-V=1.57(Weis93),
  B-V=1.585+-0.013(Mermilliod91), B-V=1.580+-0.040(HIP),
  U-B=1.218+-0.015(Mermilliod91), U-B=1.21(Weis93), V-R=1.29(Weis93),
  R-I=1.11(Weis93), V-I=2.56+-0.09(HIP), J=6.104+-0.024(2MASS),
  H=5.526+-0.016(2MASS), Ks=5.275+-0.023(2MASS). Using Casagrande08
  calibrations and 2MASS JHK photometry, mbol = 7.772+-0.014. Hence
  BCv = mbol - V = 7.772 - 10.02 = -2.248, BC_K = mbol - Ks = 7.772 -
  5.275 = 2.497.  Adopting Vmag from Weis93 (close to median of
  published values), V-Ks = 10.02 - 5.275 = 4.745. Plx = 179.01 +-
  1.60 mas (vanLeeuwen07) => Mv = 11.28, M_Ks = 6.54, Mbol = 9.04,
  logL=-1.72.  Mass = 0.372+-0.002 Msun(Jenkins09). Teffs:
  3245K(Jenkins09), 3400K(Frasca09), 3477+-11K(Wu11), 5511K(Valdes04;
  typo?!) => adopt Teff = 3400K.


GJ 15B = BD+43_44B = Gmb 34B = LHS 4
 *M3.5V: GrayAtlas,Henry94,Kirkpatrick94,Hawley97,Henry02
  M4V: Tamazian06
  M4+V: Boeshaar94(dM4+)
  M4.5Ve: Joy74
  M5V: Adams26
  M6V: JM53(non-stan)

GJ 105B =
  M3Ve: Robertson84
 *M3.5V: Henry94,Henry02
  M4V: Hawley97
  M4.5V: Joy74

  I've only deprecated this as a standard as no one else seems to have
  classified the star as M3.5V.

G 099-049
 *M3.5V: Henry94,Henry02
  M4: Lee84,Gliese91,Mason95(dM4e),Montes01,Jenkins09(M4.0),Gaido14
  M0: Lee47

  I've only deprecated this as a standard as no one else seems to have
  classified the star as M3.5V.
  
GJ 300 = 
 *M3.5V: Henry94,Henry02
  M4V: Hawley97,Reid04

  Skiff07 compendium has no SpTs published before Henry's.

GJ 829 AB = Ross 775 = StKM 1-1903
 *M3.5V: Joy74,Kirkpatrick92(PhD),Henry94(J),Henry02(J),Reid04(B only),Kirkpatrick12
  M3: Stephenson86

  Joy/Henry/Reid agreement, but unresolved binary. Kirkpatrick12 cites Kirkpatrick92(PhD thesis)
  and calls the system M3.5V + M3.5:V. 

GJ 896 AC = BD+19 5116 AC = EQ Peg A = LFT 1799 = LHS 3965
 *M3.5V: Henry94(J),Hawley97(A only),Henry02(J)
  M4V: Tamazian06,Joy74(M4Ve),KeenanMcNeil76(stan)

  Unresolved binary. Was the KeenanMcNeil76 M4V standard ("M4Ve"), but
  apparently it was not considered M4V standard by anyone afterwards.
  More recently Henry+ and Hawley+ agree on M3.5V. Leggett96: flux =
  1.29e-11 W/m^2, logL=-1.75, mbol=8.25, Mbol=9.13, BCv=-2.13,
  BC_K=2.67. Mbol=9.05(Morales08). Teffs: 3090K(Jenkins09),
  3200K(Prugniel11), 3280K(Morales08), 3400+-150K(Leggett96),
  3630K(Zboril98) => median Teff = 3280K.  Mass: 0.378+-0.042
  Msun(Jenkins09). Plx=151.9+-3.7 mas.

GJ 273 = BD+05_1668 = Luyten's star
  M3: Lee47
 *M3.5V: Bidelman85,Kirkpatrick91(pri,Kirkpatrick12),Kirkpatrick93,Kirkpatrick94,Henry02,Lepine13,Alonso-Floriano15
  M3.8: Mann15
  M4V: Joy74,Boeshaar76(stan),Newton14(near-IR)

  Kirkpatrick91 moved the subtype 0.5 earlier than Boeshaar76.  Teffs:
  3280K(Lepine13), 3317+-60K(Mann15), 3322+-78K(Newton15) => median
  Teff = 3317K. V=9.832+-0.019(Mermilliod91),
  B-V=1.554+-0.006(Mermilliod91), Ks=4.857+-0.023(2MASS) => V-Ks =
  9.832 - 4.857 = 4.975. Rabus19: tetLD=0.783+-0.010,
  Fbol=(2.288+-0.118)e-8 erg/s/cm2 (=>mbol = 7.604+-0.056 IAU2015
  scale), Rad=0.320+-0.005Rsun, Teff=3253+-39K. BCv = 7.604 - 9.832 =
  -2.228.

G 203-047AB 
 *M3.5V: Henry94(J),Hawley97,Henry02(J)

  Unresolved binary.

GJ 860A = Kruger 60A = HD 239960 = BD+56_2783  = DO Cep (J2227+5741) 
 *M3V: Adams26,Neckel58(M3),Christy69,Henry94,Hawley97,Henry02,Tamazian06
  M3.5V: Joy74,KeenanMcNeil76(stan)
  M5: Nassau54

  3.4" binary with V=11.30 star GJ 860B (see "M4V" file).
  V=9.85(Gliese91), V=9.81(Tycho), B-V=1.62(Gliese91),
  U-B=1.23(Gliese91).  HIP V, B-V, and V-I are for unresolved GJ
  860AB, and GJ 860 is unresolved in 2MASS. Significantly redder in
  B-V than GJ752A (B-V = 1.62 vs. 1.464, respectively).

# Non-standards

GJ 687 = HIP 86162 = BD+68_946 = DO 35853 = G 240-063 = LFT 1364 = LHS 450 
 *M3V: Adams35,Luyten79,Bidelman85,Henry94,Hawley97,Henry02
  M4V: Adams26,Joy74
  M3.5V: JM53(non-stan.)
  M2: Lee47
  M5V: Vyssotsky52

  Here because it was listed as a non-standard M3.5V in
  JohnsonMorgan53.  WDS lists BC component at separation 302" away,
  however it is not clear whether it is physical. V=9.15(HIP),
  V=9.17(Weis93), B-V=1.505+-0.013(HIP), B-V=1.47(Weis93),
  V-R=1.26(Weis93), R-I=1.11(Weis93),
  V-I=2.11+-0.10(HIP). J=5.335+-0.021(2MASS), H =
  4.766+-0.033(2MASS,flag='E'), Ks = 4.548+-0.021(2MASS).  Hence V-Ks
  = 9.15 - 4.548 = 4.602. Using Casagrande08 relations, the 2MASS JHK
  photometry is consistent with mbol = 6.967 +- 0.020, hence BCv =
  mbol - V = 6.967 - 9.15 = -2.183, BC_Ks = mbol - Ks = 2.419.  Plx =
  220.84+-0.94 mas(van Leeuwen07) => Mv = 10.87, M_Ks = 6.27, Mbol =
  8.69+-0.02, logL = -1.58+-0.01. Teffs: 3237K(Jenkins09),
  3395K(RojasAyalas12), 3583K(Soubiran08), 3748K(Masana06) => median
  Teff = 3489 K. Radius = 0.372+-0.008 Rsun(Masana06). BC_K =
  2.499+-0.054(Masana06).  BCv = -2.103+-0.072(Masana06). Nidever02
  quotes GJ 687 as being a very stable RV star (rms < 100 m/s over ~3
  years), so unlikely to be an unresolved binary star.

GJ 752A = HD 180617 = LHS 473 = Wolf 1055 = V1428 Aql = HIP 94761 (J1916+0510)
 *M3V: Lee47(M3),Joy74,Boeshaar76(stan),Boeshaar85(dM3),Kirkpatrick91(pri),Kirkpatrick94,Henry94,Boeshaar94,Henry02,Kirkpatrick(GrayCorbally09)
  M3-V: Keenan88
  M3.5V: JM53
  M2.5V: Hawley97
  M2III: Houk99(q=3)

  Here because non-standard in JohnsonMorgan53.  Continuity as M3V
  standard from Boeshaar, Kirkpatrick, & Henry, and Kirkpatrick
  considers this the primary standard.  Unfortunately 3 expert
  classifiers have it +-0.5 subtype different from M3V
  (e.g. JohnsonMorgan53, Keenan88, Hawley97). It is also a bit bluer
  and brighter than all the other M3V "standards", so it might be best
  considered M3-V? GJ 752B is ~75" away (Lepine07).  V=9.12(HIP),
  B-V=1.464+-0.005(HIP), V-I=2.32+-0.00(HIP), R-I=1.29(Delfosse98),
  J=5.583+-0.030(2MASS), H=4.929+-0.027, Ks=4.673+-0.020(2MASS),
  V-J=3.537(HIP & 2MASS), (V-Ks)=4.447(HIP & 2MASS).  mbol =
  7.158+-0.022 using 2MASS JHKs and Casagrande08 calibration => BCv =
  mbol - V = 7.158 - 9.12 = -1.962, BC_Ks = 2.485.  Plx = 170.36+-1.00
  mas => Mv = 10.28, M_Ks = 5.83+-0.02, Mbol = 8.32+-0.03, logL =
  -1.43+-0.01. Teffs: 3240K(Berriman92), 3250K(ReidHawley05),
  3300K(Reid84), 3368K(Berger06#1), 3390K(Berger06#2), 3475K(Tsuji96),
  3343K(Casagrande08), 3789K(RojasAyala12) => median Teff ~ 3380 K.

BD+4_4226 = DO 6166 = IRAS 19444+0420
  M3.5:V : JM53(non-standard)
  M1: Lee47

  note that this is a V=9.6mag M-star with negligible p.m., later
  classified as a M1III. Pickles10 reports that the colors are
  consistent with M3III. V=10.070(Mermilliod91),
  B-V=1.440(Mermilliod91). Gaia DR1 parallax = 0.45+-0.45, which ices
  it as distant M giant, not M dwarf!

# Other Stars

GJ 163 = HIP 19394 = L 229-91 = LHS 188 = L 229-91 = LPM 178 = NLTT 12693 = 2MASS J04091567-5322254
  M2.8+-0.5: Sebastian21
  M3: Houdebine17
  dM3.4: Houdebine19
  M3.5V: Walker83,Reid95
  
  3 exoplanets (Bonfils13), c is in optimisic hab zone + possible 4th
  (Tuomi13).  V=11.79(HIP), V=11.793+-0.005(Mermilliod91),
  V=11.811(Koen10,Casagrande08), B-V=1.480+-0.008(HIP),
  B-V=1.487+-0.033(Mermilliod91), U-B=1.095(Koen10),
  U-B=1.180(Mermilliod91), B-V=1.491(Casagrande08,Koen10),
  V-Ic=2.491(Koen10), V-I=2.50+-0.02(HIP), Ks=7.135+-0.021(2MASS),
  V-Ks = 11.793 - 7.135 = 4.658, mbol=9.826(Casagrande08). GaiaDR3:
  G=10.683944+-0.002808, Bp-Rp=2.561426, Bp-G=1.395229, G-Rp=1.166197.
  plx=66.0705+-0.0172mas(GaiaDR3).  Teffs: 3161K(GaiaDR3/MSC2),
  3209K(Anders19), 3223+-172K(Santos13), 3247+-66K(Casagrande08),
  3300K(Morales08), 3360+-88K(Muirhead18), 3373K(Anders22),
  3375+-42K(Houdebine19), 3399K(Suissa20), 3399+-157K(Paegert21),
  3400K(Martinez-Rodriguez19), 3417+-100K(Houdebine16),
  3447+-42K(Gaidos14), 3476+-105K(Sebastian21), 3501K(GaiaDR3/MSC1),
  3600K(GaiaDR3/RVtemp) => <Teff> = 3375K.  Masses:
  0.35+-0.05(Gaidos14), 0.40+-0.01Msun(Sebastian21),
  0.402+-0.02Msun(Paegert21), 0.40243Msun(Suissa20),
  0.450+-0.005Msun(Muirhead18).  Luminosity:
  -1.6635+-0.0074(Martinez-Rodriguez19), -1.69486(Suissa20),
  -1.69486+-0.10892(Paegert21), -1.796+-0.082(Gaidos14).  SED fit
  7/16/2022: Teff=3420K, BCv=-1.952, mbol=9.841, Mbol=8.941,
  logL=-1.674.

GJ 682 = HIP 86214 
 *M3.5V: Bidelman85(M3.5),Reid95
  M4.5V: Walker83
  M5: Gaidos14

  Listed as it is a very nearby (d=5pc) exoplanet host.  WDS reports
  it as tight (0.2") binary WDS J17371-4419 = WDK3 with mag1=6.3,
  mag2=7.3 from Ward-Duong15. The actual Ward-Duong15 paper reports
  sep=0.17+-0.05", projected sep 0.9+-0.3 au, del(H)=1.01, which they
  claim correspond to two stars of masses 0.23 and 0.14 Msun. However
  the RV data from Tuomi14 show no signs of a stellar companion - just
  two RV signals they attribute to planets with amplitudes 2.99 and
  3.98 m/s.  Star is in pretty crowded Galactic
  field. plx=199.6944+-0.0312mas(GaiaDR3).  V=10.94(HIP),
  V=10.96(Mermilliod91), B-V=1.65(Mermilliod91),
  U-B=1.20(Mermilliiod91).  Teffs: 3028K(Tuomi14),
  3261+-86K(Muirhead18).  Masses: M=0.27Msun(Tuomi14),
  M=0.295+-0.005(Muirhead18).  logL=-2.0555+-0.1136(Paegert21).
  


CU Cnc: Ribas03 presents a detailed study of the near-identical
M3.5Ve+M3.5Ve binary CU Cnc: M_A = 0.4333+-0.0017 Msun, M_B =
0.3980+-0.0014 Msun, R_A=0.4317+-0.0052 Rsun, R_B=0.3908+-0.0094 Rsun,
mean Teff = 3140+-150 K. Ribas03 estimates the age to be ~320 Myr and
metallicity [Fe/H] ~ 0.0.