M4V GJ 402 is the best M4V standard. Note that the the radius discontinuity pointed out by Rabus19 (where for Teff=3200K-3340K, radii vary widely between 0.18 to 0.42 Rsun) is present for M4 dwarfs. For Teff=3220K, the M_Ks vs. Rad trend of Rabus predicts R=0.214Rsun, whereas Mann15 fits a trend through this messy M3-M4 region and predicts R=0.257Rsun for [Fe/H]=0.0 and M_Ks=7.5. I adopt the Mann15 trend for the HR diagram position. Boeshaar76 standard: GJ 273 - M4 (plates II & V standards) Boeshaar76 standard: GJ 896B - M4+e (plate IV standard) KeenanMcNeil76 standard: EQ Peg (=GJ 896A) - M4V Keenan85 standard: gam Leo C - M4V Boeshaar85 standard: GJ 402 - M4V GJ 852A - M4V (in Table II) Kirkpatrick91 standard: GJ 402 - M4V (primary standard) GJ 213 - M4V (primary standard GJ 275.2A - M4V (primary standard) GJ 699 (Barnard) - M4V (secondary stan.) GJ 232 - M4V (secondary standard) Kirkpatrick94 standards: GJ 169.1A (Stein2051A) - M4V GJ 213 (Ross 47) - M4V Hawley02 standard: GJ 213 - M4V Henry02 standards: GJ 1005AB - M4VJ (cites Henry94) GJ 213 - M4V (cites Kirkpatrick91) GJ 232 - M4V (cites Kirkpatrick91) GJ 285 - M4V (cites Henry94) GJ 299 - M4V (cites Henry94) GJ 402 - M4V (cites Kirkpatrick91) GJ 447 - M4V (cites Henry94) GJ 699 - M4V (cites Kirkpatrick91) GJ 860B - M4V (cites Henry94) Kirkpatrick(in GrayCorbally09): GJ 402 - M4V Kirkpatrick10 GJ 213 - M4V Pecaut13 standard: GJ 402 - M4V Kirkpatrick16 standard: GJ 402 (=Wolf 358) - M4V (M4V) = 1.424 ; Crawford76 (B-V)(M4V) = 1.44 ; exemplar GJ 1006 A (M4V) = 1.52 ; Fitzgerald70 (B-V)(M4V) = 1.54 ; SchmidtKaler82 (B-V)(M4V) = 1.541 ; median SIMBAD M4V d<25pc (N=169) (M4V) = 1.56 ; Johnson66 (B-V)(M4V) = 1.56 ; exemplar GJ 398 (B-V)(M4V) = 1.60 ; KenyonHartmann95 (B-V)(M4V) = 1.600 ; sec. stan. GJ 285 (B-V)(M4V) = 1.60 ; Bessell91 "old disk" (B-V)(M4V) = 1.63 ; exemplar GJ 609 (B-V)(M4V) = 1.637 ; ter. stan. GJ 169.1A (M4V) = 1.644 ; pri. stan. GJ 402 (B-V)(M4V) = 1.65 ; Leggett92 "young disk" (M4V) = 1.653 (N=1; Gray01/03/06; HIP 103039) (B-V)(M4V) = 1.667 (+-0.023 sem,+-0.083 stdev); med. for 18 ARICNS M4V stars (B-V)(M4V) = 1.675 ; pri. stan. GJ 213 (M4V) = 1.677 ; ShayaOlling11 (B-V)(M4V) = 1.694 ; ter. stan. GJ 275.2A (B-V)(M4V) = 1.746 ; sec. stan. GJ 447 (B-V)(M4V) = 1.76 ; sec. stan. GJ 232 (B-V)(M4V) = 1.768 ; sec. stan. GJ 299 => adopt (B-V)(M4V) = 1.65 [updated 7/5/2020] (U-B)(M4V) = 1.087 +-0.093 ; ter. stan. GJ 285 (M4V) = 1.14 ; Johnson66 (U-B)(M4V) = 1.179 ; ter. stan. GJ 169.1A (U-B)(M4V) = 1.18 +-0.035 ; ter. stan. GJ 275.2 (U-B)(M4V) = 1.213 +-0.0092 ; pri. stan. GJ 402 (U-B)(M4V) = 1.222 ; trend U-B for B-V=1.661 among Landolt M dwarf phot standards (U-B)(M4V) = 1.295 +-0.179 ; ter. stan. GJ 299 (U-B)(M4V) = 1.355 +-0.160 ; sec. stan. GJ 447 => adopt(U-B)(M4V) = 1.222 (M4V) = 1.70 ; Johnson66 (V-R)(M4V) = 1.23 ; Bessell91 "old disk" (V-R)(M4V) = 1.216 ; pri. stan. GJ 402 (R-I)(M4V) = 1.63 ; Bessell91 "old disk" (R-I)(M4V) = 1.568 ; pri. stan. GJ 402 (G-J)(M4V) = 2.733 ; Bentley18 (G-Ks)(M4V) = 3.585 ; Bentley18 (Ks-W2)(M4V) = 0.328 ; Bentley18 (W1-W2)(M4V) = 0.166 ; Bentley18 (Ks-W1)(M4V) = 0.150 ; Best18 (Ks-W1)(M4V) = 0.162 ; Bentley18 (Ks-W1)(M4V) = 0.182 ; Avenhaus12 for V-Ks=5.20 (Ks-W1)(M4V) = 0.184 ; fit to Winters15 data for V-Ks=5.20 => adopt (Ks-W1)(M4V) = 0.18 [updated 12/29/2019] (M4V) = 2.730 (N=1; Gray01/03/06; HIP 103039) (V-I)(M4V) = 2.786 ; pri. stan. GJ 402 (V-I)(M4V) = 2.80 ; Leggett92 "young disk" (V-I)(M4V) = 2.85 ; Hawley96 (V-I)(M4V) = 2.86 ; Bessell91 "old disk" (M4V) = 3.19 ; Johnson66 (M4V) = 3.97 ; Johnson66 (M4V) = 4.438 +-0.049 (sem) (stdev =0.121; 7 standards) (M4V) = 4.45 (+-0.41 stdev) ; Lepine12 (V-Ks)(M4V) = 4.828 ; non-standard GJ 388 (M4V) = 4.87 ; Johnson66 (V-Ks)(M4V) = 5.03 ; trend fit to Dahn17 for M4V (V-Ks)(M4V) = 5.038 ; exemplar GJ 398 (V-Ks)(M4V) = 5.14 ; deprecated standard GJ1005 AB (V-Ks)(M4V) = 5.149 ; sec. stan. GJ 232 (V-Ks)(M4V) = 5.171 ; pri. stan. GJ 213 (V-Ks)(M4V) = 5.174 ; ter. stan. GJ 299 (M4V) = 5.18 ; Beuermann06 (V-K_CIT)(M4V) = 5.18 ; Leggett92 "young disk" (V-Ks)(M4V) = 5.185 ; exemplar GJ 609 (M4V) = 5.197 ; ter. stan. GJ 275.2A (V-K)(M4V) = 5.2 ; Hawley96 (V-Ks)(M4V) = 5.236 ; exemplar GJ 766A (V-Ks)(M4V) = 5.242 ; exemplar GJ 1006 A (V-Ks)(M4V) = 5.255 ; interp [M/H] vs. V-Ks for pri. standards (for [M/H]=0) (V-Ks)(M4V) = 5.304 ; pri. stan. GJ 402 (V-K)(M4V) = 5.28 ; Bessell91 "old disk" (V-Ks)(M4V) = 5.372 ; ter. stan. GJ 169.1A (V-Ks)(M4V) = 5.466 ; sec. stan. GJ 447 (V-Ks)(M4V) = 5.482 ; exemplar GJ 324B = 55 Cnc B ([Fe/H] ~ +0.33) (V-Ks)(M4V) = 5.492 ; ter. stan. GJ 285 => adopt (V-Ks)(M4V) = 5.25 *** [updated 12/10/2020] [EEM 12/10/2020: note the trend among the pri/sec standards is (V-Ks) = 5.323 + 0.668*[M/H] (rms=0.14). For just the two primary standards: (V-Ks) = 5.255 + 0.493*[M/H]). 5.2 appears to be too blue for solar, and pri. stan. (V-Ks=5.304) should be slightly redder than solar value due to slight metal richness. Adopt V-Ks=5.25.] => adopt (V-I)(M4V) = 2.856 => adopt (V-R)(M4V) = 1.250 => adopt (R-I)(M4V) = 1.606 => adopt (V-J)(M4V) = 4.411 => adopt (V-H)(M4V) = 4.968 => adopt (H-Ks)(M4V) = 0.282 => adopt (J-H)(M4V) = 0.557 => adopt (J-Ks)(M4V) = 0.839 => adopt (I-Ks)(M4V) = 2.394 (M4V) = 0.87 ; Beuermann06 (M4V) = 0.26 ; Beuermann06 (Bp-Rp)(M4V) = 2.5862 ; L_205-128 M4V (Bp-Rp)(M4V) = 2.72 ; Kiman19 (Bp-Rp)(M4V) = 2.7695 ; Ross_1015 M4V (Bp-Rp)(M4V) = 2.8191 ; G_160-28 M4V (Bp-Rp)(M4V) = 2.8203 ; UCAC4_642-113039 M4V (Bp-Rp)(M4V) = 2.8736 ; GJ_402 pri. stan. (Bp-Rp)(M4V) = 2.8746 ; GJ_213 pri. stan. (Bp-Rp)(M4V) = 2.9110 ; HD_102365B M4V (Bp-Rp)(M4V) = 2.9126 ; GJ_169.1A ter. stan. (Bp-Rp)(M4V) = 2.936 ; median for d<10pc M4V (N=24) (Bp-Rp)(M4V) = 2.9537 ; L_674-15 M4V (Bp-Rp)(M4V) = 2.9590 ; GJ_232 sec. stan. (Bp-Rp)(M4V) = 2.9644 ; GJ_275.2A ter. stan. (Bp-Rp)(M4V) = 2.9966 ; GJ_299 ter. stan. (Bp-Rp)(M4V) = 3.0034 ; GJ_285 ter. stan. (Bp-Rp)(M4V) = 3.0230 ; *_alf_PsA_C M4.0V (Bp-Rp)(M4V) = 3.0425 ; LP_656-38 M4V (Bp-Rp)(M4V) = 3.0426 ; GJ_447 sec. stan. (Bp-Rp)(M4V) = 3.0667 ; L_471-42 M4V (Bp-Rp)(M4V) = 3.2036 ; G_42-24 M4V => adopt (Bp-Rp)(M4V) = 2.874 [updated 12/10/2020] (G-Rp)(M4V) = 1.2131 ; GJ_213 pri. stan. (G-Rp)(M4V) = 1.2154 ; GJ_402 pri. stan. (G-Rp)(M4V) = 1.2165 ; GJ_299 ter. stan. (G-Rp)(M4V) = 1.23 ; Kiman19 (G-Rp)(M4V) = 1.2337 ; GJ_169.1A ter. stan. (G-Rp)(M4V) = 1.237 ; color trend M0V-M9V (G-Rp)(M4V) = 1.2406 ; GJ_232 sec. stan. (G-Rp)(M4V) = 1.241 ; SIMBAD d<10pc median (N=23) (G-Rp)(M4V) = 1.2443 ; GJ_285 ter. stan. (G-Rp)(M4V) = 1.2453 ; GJ_447 sec. stan. (G-Rp)(M4V) = 1.2465 ; GJ_275.2A ter. stan. => adopt (G-Rp)(M4V) = 1.214 [updated 12/10/2020] (Bp-G)(M4V) = 1.49 ; Kiman19 (Bp-G)(M4V) = 1.6582 ; GJ_402 (Bp-G)(M4V) = 1.6615 ; GJ_213 (Bp-G)(M4V) = 1.6789 ; GJ_169.1A (Bp-G)(M4V) = 1.70 ; Bp-Gp=2.94, G-Rp=1.24 (Bp-G)(M4V) = 1.7179 ; GJ_275.2A (Bp-G)(M4V) = 1.7184 ; GJ_232 (Bp-G)(M4V) = 1.7591 ; GJ_285 (Bp-G)(M4V) = 1.7801 ; GJ_299 (Bp-G)(M4V) = 1.7973 ; GJ_447 => adopt (Bp-G)(M4V) = 1.66 [updated 12/10/2020] (Bp-Gp=2.874, G-Rp=1.214) (G-V)(M4V) = -1.5623 ; GJ_447 (G-V)(M4V) = -1.5443 ; GJ_285 (G-V)(M4V) = -1.4583 ; GJ_299 (G-V)(M4V) = -1.4099 ; GJ_213 pri. stan. (G-V)(M4V) = -1.4066 ; GJ_275.2A (G-V)(M4V) = -1.40 ; M_G=11.30, Mv=12.70 (G-V)(M4V) = -1.3965 ; GJ_402 pri. stan. (G-V)(M4V) = -1.3909 ; GJ_169.1A (G-V)(M4V) = -1.3861 ; GJ_232 (G-V)(M4V) = -1.351 ; median M4V d<60pc N=225 (likely biased blue) (G-V)(M4V) = -1.330 ; polynomial fit to SIMBAD d<25pc M dwarfs => adopt (G-V)(M4V) = -1.40 [updated 12/10/2020] => adopt (G-Ks)(M4V) = 3.85 = 5.25 + -1.40 [updated 12/15/2020] (g-r)(M4V) = 1.48 ; Covey07 (r-i)(M4V) = 1.46 (+-0.15 rms) ; West08 (r-i)(M4V) = 1.566 (+-0.05 rms) ; West05 fit for (V-Ic)=2.856 (i-z)(M4V) = 0.79 (+-0.09; rms) ; West08 (i-z)(M4V) = 0.818 ; poly fit to d<75pc M dwarfs in SIMBAD for G-Ks=3.85 => adopt (i-z)(M4V) = 0.82 [updated 12/27/2021] (z-J)(M4V) = 1.45 (+-0.16 rms) ; West08 (z-J)(M4V) = 1.471 (+-0.053 rms) ; poly fit to d<50pc SIMBAD M dwarfs for G-Ks=3.85 => adopt (z-J)(M4V) = 1.47 [updated 12/27/2021] Mv(M4V) = 10.70 ; Wegner07 (clearly in error, or biased somehow!) Mv(M4V) = 11.3 ; Schmidt-Kaler82 Mv(M4V) = 12.245 ; ter. stan. GJ 285 Mv(M4V) = 12.33 ; median SIMBAD M4V d<25pc (N=169) Mv(M4V) = 12.357 ; ter. stan. GJ 169.1A Mv(M4V) = 12.45 ; EEM fit to Reid CNS3 data for V-K=5.24) Mv(M4V) ~ 12.5 ; (see Fig. 9 of Riedel+2010 for V-K=5.24) Mv(M4V) = 12.525 ; pri. stan. GJ 402 (see below) Mv(M4V) = 12.61 ; M_Ks=7.36, V-Ks=5.25 Mv(M4V) = 12.67 ; EEM fit to Winters+2015 data for V-K=5.25] Mv(M4V) = 12.70 ; M_G=11.3, G-V=-1.40 Mv(M4V) = 12.732 ; pri. stan. GJ 213 (see below) Mv(M4V) = 12.79 ; JohnsonApps09 calibration for V-K=5.24 Mv(M4V) = 12.9 ; Reid04 Mv(M4V) = 12.95 ; Kirkpatrick94 Mv(M4V) = 12.96 ; Henry94 Mv(M4V) = 13.344 ; ter. stan. GJ 275.2A (see below) Mv(M4V) = 13.40 ; non-stan. GJ 22C (Dieterich21) [Fe/H]=-0.10 Mv(M4V) = 13.445 ; sec. stan. GJ 232 (see below) Mv(M4V) = 13.473 ; sec. stan. GJ 447 (see below) Mv(M4V) = 13.685 ; ter. stan. GJ 299 (see below) => adopt Mv(M4V) = 12.61 mag [updated 12/10/2020] (M_Ks=7.36, V-Ks=5.25) => adopt M_G(M4V) = 11.21 mag [updated 12/10/2020] (Mv=12.61, G-V=-1.40) => adopt M_Ks(M4V) = 7.36 mag [updated 12/10/2020] (Mv=12.61, V-Ks=5.25) M_G(M4V) = 9.726 ; BD+20 2465 M_G(M4V) = 9.823 ; Ross 104 M_G(M4V) = 11.063 ; GJ 402 = Wolf 358 pri. stan. M_G(M4V) = 11.21 ; Mv=12.61, G-V=-1.40 M_G(M4V) = 11.285 ; GJ 213 = Ross 47 pri. stan. M_G(M4V) = 11.325 ; LP 816-60 M_G(M4V) = 11.325 ; d<10pc SIMBAD M4V median (N=23) M_G(M4V) = 11.327 ; trend SIMBAD d<10pc sample M_G(M4V) = 11.658 ; G 158-50 M_G(M4V) = 11.86 ; Kiman19 M_G(M4V) = 11.886 ; NAME Barnard's star M_G(M4V) = 11.900 ; HD 239960B M_G(M4V) = 11.949 ; Ross 128 M_G(M4V) = 12.028 ; Ross 64 Note: M4V M_G values range from 8.2 to 12.38 among d<10pc SIMBAD stars, rms scatter is 1.2 mag!] M_Ks(M4V) = 8.511 ; ter. stan. GJ 299 M_Ks(M4V) = 8.307 ; sec. stan. GJ 232 M_Ks(M4V) = 8.147 ; ter. stan. GJ 275.2A M_Ks(M4V) = 8.12 ; non-stan. GJ 22C (Dieterich21) [Fe/H]=-0.10 M_Ks(M4V) = 8.025 ; sec. stan. GJ 447 M_Ks(M4V) = 7.561 ; pri. stan. GJ 213 M_Ks(M4V) = 7.43 ; V-Ks=5.25 => JohnsonApps2009 calibration M_Ks(M4V) = 7.35 ; interp. pri. standards M_Ks vs. [M/H] (for [M/H]=0.0) M_Ks(M4V) = 7.36 ; V-K=5.25 => Finch14 calibration M_Ks(M4V) = 7.37 ; V-K=5.25 => EEM fit to Winters+2015 data M_Ks(M4V) = 7.30 ; V-K=5.25 => Schlaufman10 calibration M_Ks(M4V) = 7.23 ; V-K=5.25 => EEM fit to Reid CNS3 data M_Ks(M4V) = 7.221 ; pri. stan. GJ 402 M_Ks(M4V) = 6.985 ; ter. stan. GJ 169.1 M_Ks(M4V) = 6.823 ; ter. stan. GJ 285 Teff(M4V) = 3019 K ; mean photometric Teff Teff(M4V) = 3089 +- 11 K ; Pecaut13 (sec. stan. GJ 699) Teff(M4V) = 3125 K ; ter. standard GJ 299 (median Teff) Teff(M4V) = 3136 K ; EEM N=34 Teffs Teff(M4V) = 3150 K ; non-standard star Barnard's Star (median Teff; but metal poor?) Teff(M4V) = 3150 K ; exemplar GJ 447 Teff(M4V) = 3150 K ; Bessell91 "old disk" Teff(M4V) = 3162 K ; RojasAyala12(mean N=29 M4V stars) Teff(M4V) = 3165 K ; Morrell19 for stars w/i +-0.05 mag of M_Ks=7.50 Teff(M4V) = 3196 K ; non-stan. GJ 22C (Dieterich21) [Fe/H]=-0.10 Teff(M4V) = 3200 K ; Rajpurohit13(N=16) Teff(M4V) = 3200 K ; sec. stan. GJ 232 Teff(M4V) = 3204 +- 76 K ; Lepine12 Teff(M4V) = 3210 K ; Rad=0.257 Rsun for Mann15 calib for M_Ks=7.5, [Fe/H]=0.0 Teff(M4V) = 3220 K ; empirical L-R relation, for logL=-2.20 Teff(M4V) = 3222 +- 10 K ; Boyajian12b (N=1) Teff(M4V) = 3240 K ; exemplar GJ 324B = 55 Cnc B ([Fe/H] ~ +0.33) Teff(M4V) = 3250 K ; sec. stan. GJ 213 (median Teff) Teff(M4V) = 3263 K ; exemplar GJ 609 Teff(M4V) = 3272 K ; ter. stan. GJ 169.1A Teff(M4V) = 3273 K ; pri. stan. GJ 402 Teff(M4V) = 3274 K ; exemplar GJ 1006 A Teff(M4V) = 3275 K ; non-standard GJ 1001 (Golimowski04, Kirkpatrick unpub. SpT) Teff(M4V) = 3300 K ; Johnson66 Teff(M4V) = 3306 K ; Rajpurohit18 (mean for N=47 M4Vs) Teff(M4V) = 3326 K ; Passegger18 median Teff for CARMENES M4.0Vs(N=41) Teff(M4V) = 3328 K ; exemplar GJ 398 Teff(M4V) = 3370 K ; Schmidt-Kaler82 Teff(M4V) = 3450 K ; Bertone04[NextGen] => adopt Teff(M4V) = 3210 K (logT = 3.507) [updated 4/9/2020] BCv(M4V) = -1.77 mag ; Bertone04[NextGen] BCv(M4V) = -1.964 mag ; EEM fit to Casagrande08 data for Teff=3250K BCv(M4V) = -2.25 mag ; Schmidt-Kaler82(BCv=-2.38 + 0.13 offset) BCv(M4V) = -2.33 mag ; non-standard Barnard's star (Leggett96) BCv(M4V) = -2.338 mag ; non-standard Barnard's star (GJ 699) (Pecaut13) BCv(M4V) = -2.380 mag ; Casagrande18(Teff=3250K) BCv(M4V) = -2.452 mag ; Mann15(V-J=4.363) BCv(M4V) = -2.46 mag ; sec. stan. GJ 213 (Leggett96) BCv(M4V) = -2.475 mag ; pri. stan. GJ 402 (Mann15) BCv(M4V) = -2.50 mag ; tertiary stan. GJ 299 (Leggett96) BCv(M4V) = -2.51 mag ; BC_K=2.74, V-Ks=5.25 BCv(M4V) = -2.540 mag ; pri. stan. GJ 213 (Mann15) BCv(M4V) = -2.56 mag ; Bessell91("old disk"; BCv = (V-I)-BC_I) BCv(M4V) = -2.686 mag ; exemplar GJ 324B = 55 Cnc B ([Fe/H] ~ +0.33) BCv(M4V) = -3.382 mag ; Flower96(Teff=3250K) => adopt BCv(M4V) = -2.51 mag [updated 1/15/2021; BC_Ks=2.74, V-Ks=5.25] BC_K(M4V) = 2.829 mag ; pri. stan. GJ 402 (Mann15) BC_Ks(M4V)= 2.796 mag ; exemplar GJ 324B = 55 Cnc B ([Fe/H] ~ +0.33) BC_K(M4V) = 2.758 mag ; Mann15(V-J=4.363) BC_K(M4V) = 2.737 mag ; Leggett01 polynomial for I-K=2.419 BC_Ks(M4V)= 2.734 mag ; Morrell19 trend for G-Ks=3.79 BC_K(M4V) = 2.71 mag ; non-standard Barnard's star (Leggett96) BC_K(M4V) = 2.70 mag ; sec. stan. GJ 213 (Leggett96) BC_K(M4V) = 2.69 mag ; sec. stan. GJ 299 (Leggett96) BC_K(M4V) = 2.668 mag ; pri. stan. GJ 213 (Mann15) BC_K(M4V) = 2.649 mag ; non-stan Barnard's star (GJ 699;Pecaut13) [mbol=7.173+-0.012,Ks=4.524+-0.020] BC_K(M4V) = 2.641 mag ; Leggett01 polynomial for J-K=0.839 => adopt BC_K(M4V) = 2.74 mag [updated 11/3/2019] logL(M4V) = -2.56 dex ; tertiary standard GJ 299 (Leggett96) logL(M4V) = -2.52 dex ; non-stan. GJ 22C (Dieterich21) [Fe/H]=-0.10 logL(M4V) = -2.46 dex ; non-standard Barnard's Star (Dawson04 & Leggett96) logL(M4V) = -2.207 dex ; Morrell19 trend for logL for M_Ks=7.50 logL(M4V) = -2.144 dex ; M_Ks=7.36, BC_K=2.74 => Mbol = 10.10 logL(M4V) = -2.18 dex ; secondary stan. GJ 213 (Leggett96) => adopt logL(M4V) = -2.144 dex [updated 11/15/2021] => adopt Mbol(M4V) = 10.100 mag [updated 11/15/2021] Mass(M4V) = 0.157+-0.003 Msun ; non-stan. GJ 22C (Dieterich21) [Fe/H]=-0.10 Mass(M4V) = 0.172+-0.008 Msun ; GJ860B (Benedict16) Mass(M4V) = 0.177+-0.029 Msun ; GJ166C (Benedict16) Mass(M4V) = 0.201 Msun ; Mv=12.6 => HenryMcCarthy93 calibration Mass(M4V) = 0.214 Msun ; Benedict16 calibration for Mv=12.61 Mass(M4V) = 0.239 Msun ; Delfosse00 calibration for M_Ks=7.36 Mass(M4V) = 0.242 Msun ; Benedict16 calibration M_Ks=7.36 Mass(M4V) = 0.244 Msun ; Mann18 calib for M_Ks=7.36 => adopt Mass(M4V) = 0.24 Msun [updated 11/15/2021] Rad(M4V) = 0.179+-0.009 Rsun ; non-stan. GJ 22C (Dieterich21) [Fe/H]=-0.10 Rad(M4V) = 0.1869+-0.0012 Rsun ; Boyajian12b (N=1) Rad(M4V) = 0.196+-0.010 Rsun ; sec. stan. GJ 447 = Ross 128 (Rabus19) Rad(M4V) = 0.200 Rsun ; non-standard star Barnard's Star (Dawson04) Rad(M4V) = 0.214 Rsun ; Rabus19 trend for Teff=3220K [low trend - low Teff edge] Rad(M4V) = 0.2717 Rsun ; Mann15 trend for M_Ks=7.36, [Fe/H]=0.0 Rad(M4V) = 0.2739 Rsun ; logL=-2.144, Teff=3210K Rad(M4V) = 0.283 Rsun ; Rabus19 trend for Teff=3220K [high trend - low Teff edge] => adopt Rad(M4V) = 0.274 Rsun [last updated 1/15/2021] # No Standards Houk75 does not list a M4V standard. Skiff08 does not flag any stars as M4V MK standards. # Primary Standard GJ 402 = Wolf 358 = EE Leo = LHS 294 = HIP 53020 (J1050+0648) M3: RojasAyala12(K-band) M3.76: Terrien15(near-IR) M3.9: Mann15 *M4V: Boeshaar76,Kirkpatrick91(pri),Hawley97,Henry02,Kirkpatrick(GrayCorbally09)(pri),Lepine13,Gaidos14(M4),Alonso-Floriano15 Landolt09 UBVRI photometric standard. Appears to be just slightly metal-rich [Fe/H] ~ +0.1 (see below). Vmag=11.64(HIP), V=11.675+-0.0033(Landolt09), B-V=1.679+-0.001(HIP), B-V=1.644+-0.0031(Landolt09), U-B=1.16(Gliese91), U-B=1.213+-0.0092(Landolt09), R-I=1.568+-0.0017(Landolt09), R-I=1.25(Gliese91), V-I=2.81(HIP), V-I=2.786+-0.0039(Landolt09), J=7.319+-0.023(2MASS), Ks=6.371+-0.016(2MASS), V-J = 4.321(HIP & 2MASS), (V-Ks) = 5.304 (Landolt09 & 2MASS). plx = 147.92+-3.52(vanLeeuwen07), plx=143.4971+-0.0626mas(GaiaDR2). Absolute magnitude calculated using V=11.675+-0.0033 and plx = 147.92+-3.52 is Mv = 12.525+-0.052, M_Ks = 7.221+-0.054. Finch14 MS for this V-K => M_Ks = 7.424 (Mv=12.728), so star is 0.20 mag *below* main sequence. Schlaufman10 calibration predicts for [Fe/H] = 0 => M_Ks = 7.37, hence star is 0.15 mag above MS. LopezSantiago06 considers it a member of the Her-Lyr association (200 Myr), *but* star is slow-rotating: (vsini < 2.5 km/s ; Stelzer13), and despite being 8 pc away, it does not appear in any X-ray catalog! Lepine13 lists EWHa=0.11A. Gaia: G=10.2785+-0.0008, Bp-Rp=2.8736, Bp-G=1.6582, G-Rp=1.2154. V-G = 11.675+-0.0033 - 10.2785+-0.0008 = 1.3965. Teffs: 3038K(Jenkins09), 3100K(Lepine13), 3110+-50K(Houdebine12), 3165K(Stelzer13), 3200K(Rajpurohit18), 3232+-92K(Hojjatpanah19), 3238+-60K(Mann15), 3238+-81K(Gaidos14) 3273+-90K(Muirhead18), 3274+-100K(Houdebine16), 3281K(Terrien15#1), 3293+-32K(Mann15#2), 3314K(Terrien15#3), 3334+-23K(RojasAyala12), 3335K(Passegger18), 3400+-63K(Gaidos14), 3414K(Terrien15#2) => = 3273K. fbol = (0.5261+-0.0055)e-8 erg/s/cm2 (Mann15) => mbol = 9.200+-0.011 (IAU2015 scale) => BCv = mbol - V = 9.200 - 11.675 = -2.475. BC_Ks = mbol - Ks = 9.200 - 6.371 = 2.829. Metallicities: [Fe/H]=-0.07+-0.09(Maldonado20), [Fe/H]=-0.06(Jenksins09), [Fe/H]=-0.02(Neves13#2), [Fe/H]=+0.01+-0.16(Schweitzer19), [Fe/H]=+0.03(Ward-Duong15), [Fe/H]=+0.06(Neves13#1), [Fe/H]=+0.08+-0.04(Hojjatpanah19), [Fe/H]=+0.11(Terrien15), [Fe/H]=+0.13+-0.11(Gaidos14), [M/H]=+0.15+-0.12(Rojas-Ayala12#1), [Fe/H]=+0.16+-0.08(Mann15), [Fe/H]=+0.20+-0.17(Rojas-Ayala12), [Fe/H]=+0.20+-0.08(Gaidos14), [Fe/H]=+0.26+-0.12(Newton14) => <[Fe/H]> ~ +0.1. GJ 213 = Ross 47 = V1352 Ori = LHS 31 = HIP 26857 (J0542+1229) *M4V: Kirkpatrick91(pri),Kirkpatrick93,Kirkpatrick94,Hawley97,Hawley02(stan),Henry02,Kirkpatrick10(opt.,near-IR) M4+V: Boeshaar76 Newton14 and Cushing05 comment on the metal-poorness of this standard ([Fe/H] ~ -0.17). Vmag=11.56(HIP), V=11.597+-0.024(Mermilliod91), B-V=1.675+-0.032(HIP), B-V=1.655+-0.009(Mermilliod91), V-I=2.83+-0.02(HIP), J=7.124+-0.021(2MASS), Ks=6.389+-0.016(2MASS), V-J=4.436(HIP & 2MASS), (V-Ks)=5.171(HIP & 2MASS). plx = 171.55+-3.99 mas (vanLeeuwen07). Calculating absolute magnitude adopting V=11.56+-0.01 and plx = 171.55+-3.99 mas, I get Mv = 12.732+-0.051. M_Ks=7.561+-0.053(2MASS, vanLeeuwen07). Leggett96 derives: flux=6.03e-12 W/m^2, logL=-2.18, mbol=9.07, Mbol=10.20, BCv=-2.46, BC_K=2.70. Teffs: 3167K(RojasAyala12), 3200K(Brett95), 3250+-150K(Leggett96), 3266+-90K(Hojjatpanah20), 3352+-72K(Casagrande08), 3375+-125K(Kirkpatrick93) => median Teff = 3250K. GaiaDR2: plx = 172.7068 +- 0.0788mas, G=10.0991+-0.0015, Bp-G = 2.8746, G-Rp = 1.6615, G-Rp=1.2131. V-G=11.56-10.0991 = 1.4609. Mann15: fbol = (0.6002+-0.0090)e-8 erg/s/cm2 => mbol = 9.057+-0.016 (IAU2015 scale) => BCv = mbol - V = 9.057 - 11.597 = -2.54 => BC_Ks = mbol - Ks = 9.057 - 6.389 = 2.668. Metallicities: [Fe/H]=0.01+-0.16(Schweitzer16), [Fe/H]=-0.11(Neves13#1), [Fe/H]=-0.16+-0.05(Hojjatpanah20), [M/H]=-0.17+-0.02(RoyasAyala12), [Fe/H]=-0.21(Neves13#2), [Fe/H]=-0.22+-0.08(Mann15), [Fe/H]=-0.25+-0.17(RoyasAyala12) # Secondary Standards GJ 232 = G 104-037 = Ross 64 (J0624+2326) *M4V: Kirkpatrick91(sec),Hawley97,Henry02,Reid04 M4.5: Lepine13,Mann15 Metal-poor (<[M/H]> ~ -0.19, see below). V=13.060(Mermilliod91,Gliese91), B-V=1.76(Mermilliod91,Gliese91), J=8.662+-0.020(2MASS), Ks=7.911+-0.016(2MASS), V-J=4.398(Mermilliod91 & 2MASS), (V-Ks)=5.149(Mermilliod91 & 2MASS). plx = 120.0+-1.9 mas (Gliese91), 120.0+-2.3 mas (Jenkins09), 119.4+-2.3 mas (Lepine05 via NStars database). Adopting the Mermilliod91 Vmag (assume+-0.01 errors) and the Jenkins09 plx, I estimate absolute magnitude Mv = 13.445+-0.043 mag. M_Ks=8.307+-0.045 (2MASS, Jenkins09 plx), Teffs: 3060K(Lepine13), 3062+-50K(Houdebine12), 3165+-60K(Mann15), 3175+-95K(Newton15), 3200K(Rajpurohit18), 3200+-70K(Muirhead18), 3216+-30K(Mann15#2), 3237+-51K(Schweitzer19), 3238K(Passegger18), 3239+-100K(Houdebine16) => = 3200K. GaiaDR2: plx = 117.7410+-0.0618 mas. Metallicities: [Fe/H]=-0.46(Newton15#2), [Fe/H]=-0.39+-0.14(Newton14,15#1), [M/H]=-0.259(Houdebine16#2), [M/H]=-0.25(Houdebine16#1,Houdebine19), [Fe/H]=-0.19+-0.12(Gaidos14), [Fe/H]=-0.18+-0.08(Mann15), [M/H]=-0.08(Rajpurohit18), [Fe/H]=-0.07+-0.16(Schweitzer19), [M/H]=+0.40(Rajpurohit18#1) => <[M/H]> ~ -0.19. GJ 447 = Ross 128 = FI Vir = LHS 315 = HIP 57548 = LSPM J1147+0048 M3: Lee47 *M4V: Bidelman85(M4),Kirkpatrick94,Henry94,Reid95/Hawley97,Henry02,RojasAyala12(near-IR) M4.3: Terrien15 M4.5V: Joy74,Lurie13,Mann15, M5V: Luyten45,Vyssotsky52,Luyten45(M5),Gaidos14 M7V: Cowley82 2nd nearest M4V dwarf (RECONS), and appears to be near solar <[M/H]> = -0.04 (see below), and closest to solar among the primary or secondary standards. V=11.12(HIP), V=11.102+-0.014(Mermilliod91), B-V=1.746+-0.020(HIP), U-B=1.355+-0.160(Mermilliod91), V-I=2.97+-0.01(HIP), J=6.505+-0.023(2MASS), Ks=5.654+-0.024(2MASS), V-J=4.615(HIP & 2MASS), (V-Ks)=5.466(HIP & 2MASS). plx = 298.04+-2.30 mas (vanLeeuwen07). Combining Mermilliod91 Vmag and vanLeeuwen07 parallax, I estimate absolute magnitude Mv = 13.473+-0.022 mag. M_Ks=8.025+-0.029(vanLeeuwen07,2MASS). Teffs: 3028+-50K(Houdebine12), 3100K(Lepine13), 3145+-78K(Gaidos14), 3150+-84K(Muirhead18), 3151+-46K(Houdebine19), 3152+-79K(Stelzer16), 3165K(Stelzer13), 3192K(Stassun18), 3223+-100K(Houdebine16), 3264+-24K(Rabus19), 3277+-73K(Gaidos14#2), 3279+-69K(Maldonado20), 3305K(GaiaDR2) => ~ 3150K. Newton14 lists rotation period 0.497d amplitude 0.002 mag (is this not too low amplitude for such a fast rotator?). Astudillo-Defru17 reports Prot=101day. Schoefer19 reports Prot=163+-3day. Rabus19 reports tetLD=0.540+-0.029mas, fbol=(1.103+-0.091)e-8 erg/s/cm2 (=>mbol = 8.396+-0.090 IAU2015 scale), Rad=0.196+-0.010Rsun, Teff=3264+-24K. Metallicities: [Fe/H]=-0.24(Neves13#2), [M/H]=-0.23(Houdebine16#2), [Fe/H]=-0.20+-0.09(Malonado20), [Fe/H]=-0.14(Neves13#1), [Fe/H]=-0.08(Terrien15), [Fe/H]=-0.04+-0.16(Schweitzer19), [M/H]=-0.04(Houdebine16#1), [M/H]=-0.04(Rajpurohit#2), [Fe/H]=-0.02+-0.08(Gaidos14,Mann15), [Fe/H]=-0.01+-0.17(Rojas-Ayala12), [M/H]=0.00(Rajpurohit18#1), [M/H]=0.00+-0.12(Rojas-Ayala12), [Fe/H]=+0.07+-0.12(Newton14) => <[M/H]> = -0.04. # Tertiary Standards GJ 275.2A = LHS 229 (J0730+4811) *M4V: Kirkpatrick91(pri) M4+:V: Boeshaar76 I'm only considering this a tertiary standard as it has not been mentioned as a standard after Kirkpatrick91 (presumably the other standards are used much more often). V=13.537+-0.020(Mermilliod91), V=13.55+-0.01(Harrington92), B-V=1.694+-0.005(Mermilliod91), B-V=1.69+-0.01 (Harrington92), U-B=1.18+-0.035(Mermilliod91), U-B=1.22+-0.04(Harrington92), J=9.141+-0.020(2MASS), Ks=8.340+-0.015(2MASS), V-J=4.396(Mermilliod91 & 2MASS), (V-Ks)=5.197(Mermilliod91 & 2MASS). Plx = 91.5+-1.3 mas (Harrington92). Adopting Mermilliod91 Vmag and Harrington92 parallax, I estimate absolute magnitude Mv = 13.344+-0.037 mag. M_Ks=8.147+-0.034(2MASS, Harrington92). GJ 285 = YZ CMi = LHS 1943 = LFT 547 *M4V: Bidelman85(M4),Stephenson86(M4V:e),Henry94,Henry02 M4.5V: Joy74,Hawley97 M5: Basri06 I only list it as tertiary since the Hawley97 type differs from the Henry94 and Henry02 types. V=11.19(HIP), V=11.120+-0.000(Mermilliod91), B-V=1.600+-0.020(HIP), U-B=1.087+-0.093(Mermilliod91), V-I=2.95+-0.02(HIP), J=6.581+-0.024(2MASS), Ks=5.698+-0.017(2MASS), V-J=4.609(HIP & 2MASS) (V-Ks)=5.492(HIP & 2MASS), Young active M dwarf. Plx = 167.88+-2.31 mas (vanLeeuwen07). Adopting Mermilliod91 Vmag and vanLeeuwen07 plx, I estimate absolute magnitude Mv = 12.245+-0.030 mag. M_Ks= 6.823+-0.034(2MASS,vanLeeuwen07). Newton15 lists this is a very metal-rich star: [Fe/H]=0.32, 0.53. Teffs: 3306+-75K(Newton15). Star's kinematics look relatively young (U,V,W = -19.7, -22.6, -7.9) and it is fast-rotating (P=2.775d) according to Newton16. GJ 299 = LHS 35 = Ross 619 *M4V: Bidelman85(M4),Henry94,Henry02(M4.0V) M4.5V: Hawley97,Kirkpatrick10 M5V: Joy74,Zakhozhaj79-96 I list this as a tertiary standard since the Hawley97 and Kirkpatrick10 types differ from the Henry94 and Henry02 types. B=14.570+-0.07(UCAC4), V=12.834+-0.015(Mermilliod91), V=12.834+-0.03(UCAC4), B-V=1.768+-0.011(Mermilliod91), U-B=1.295+-0.179(Mermilliod91), R-I=1.67(Delfosse98), I=10.049+-0.063(Droege07), J=8.424+-0.023(2MASS), H=7.927+-0.042(2MASS), Ks=7.660+-0.026(2MASS), V-J=4.410(Mermilliod91 & 2MASS) (V-Ks)=5.174(Mermilliod91 & 2MASS). Leggett96 derives: flux=1.90e-12 W/m^2, logL=-2.56, mbol=10.33, Mbol=11.15, BCv=-2.50, BC_K=2.69. Mass=0.155+-0.025(Jenkins09). Plx=148.0+-2.6 mas(Jenkin09). Adopting Mermilliod91 Vmag and Jenkins09 plx, I estimate absolute magnitude Mv = 13.685+-0.041 mag. M_Ks= 8.511+-0.046(2MASS, Jenkins09). Teffs: 3036K(Jenkins09), 3100+-150K(Leggett96), 3150+-50K(Jones96), 3199+-150K(Veeder74) => median Teff = 3125K. GJ 169.1 A = Stein 2051 A = G 175-34 A = LHS 26 = HIP 21088 *M4V: Kirkpatrick94,Henry94,Stelzer13,Gaidos14,Newton14 M4.5V: Gray03 M3: Lee47 7-10" binary with DC white dwarf. V=11.089+-0.010(Mermilliod91), B-V=1.637+-0.015(Mermilliod91), U-B=1.179+-0.035(Mermilliod91), J=6.622+-0.021(2MASS), H=6.012+-0.020(2MASS), Ks=5.717+-0.021(2MASS), V-Ks=5.372, plx=179.27+-3.23mas(VanLeeuwen07) => Mv = 12.357+-0.040 (Mermilliod91,vanLeeuwen07), M_Ks = 6.985+-0.044 (2MASS,vanLeeuwen07). Teffs: 3100K(Lepine13), 3165K(Stelzer13), 3272+-28K(RojasAyala12), 3277+-67K(Gaidos14), 3300+-78K(Newton15) => adopt Teff= 3272K. # Deprecated Standards GJ 273 = BD+05_1668 *M3.5V: Kirkpatrick91(pri),Kirkpatrick93,Henry02 M4V: Joy74,Boeshaar76(stan) M3: Lee47 Kirkpatrick91 moved the subtype 0.5 later than Boeshaar76. Probably OK as M3.5V standard. GJ 699 = Barnard's Star = LHS 57 = BD+4_3561a M5V: JM53,Abt68,Boeshaar94 *M4V: Pesch65(M4),Bidelman85(M4),Stephenson86,Kirkpatrick91(sec),Kirkpatrick94,Henry02,Geballe02 sdM4.5: Joy74 MPE: Houk82 I'm assuming "MPE" is M-peculiar? Not agreement between Johnson/Morgan/Abt & Kirkpatrick. Metal poor? But Zboril98 lists [Fe/H]=-0.15. Boeshaar94 says that Barnard's star is one of the M stars that anchors the M-star classification system as M5V (along with HD 95735 providing the M2V standard), but that *both* stars are "spectroscopically peculiar", and there have been no other classifications as M5 since then. Dawson04: logL=-2.46+-0.02 dex, Radius = 0.200+-0.008 Rsun. Leggett96: flux=3.33e-11 W/m^2, logL=-2.46 dex, mbol=7.22, Mbol=10.91, BCv=-2.33, BC_K=2.71. Teffs: 3100+-150K(Leggett96), 3134+-102K(Dawson04), 3145K(Casagrande08), 3163K(Segranson03 VLTI), 3210K(Tsuji96), 3300+-100K(Jones02,[Fe/H]=-0.5) => adopt Teff = 3150K. Other Segransan03 VLTI parameters: M = 0.158+-0.008 Msun, R = 0.196+-0.008 Rsun, logg=5.05+-0.09 dex. GJ 860B = Kruger 60 B(J2228+5741) *M4V: Henry94,Kirkpatrick94,Hawley97,Henry02 3.4" binary with A (CCDM). Unresolved in 2MASS & Mermilliod91 photometric catalog. V(A)=11.84, V(B)=13.29 (Hawley97). Henry02 calls "A" M3.0V and "B" M4.0V> Probably not the best standard given tight binarity. Binary: 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 (V(AB)=9.59), B-V, and V-I are for unresolved GJ 860AB, and GJ 860 is unresolved in 2MASS. V(AB)=9.587+-0.015(Mermilliod91). Gliese91 resolves as V(A)=9.85, V(B)=11.30, i.e. del(V)=1.45. Significantly redder in B-V than GJ752A (B-V = 1.62 vs. 1.464, respectively). GaiaDR3 resolves G(A)=8.669386, G(B)=9.980165, del(G)=1.31. HIP CCDM lists Hp(A)=9.795+-0.012, Hp(B)=11.406+-0.050 => delta(Hp)=1.611+-0.051. Adopting delta(V)=1.45 from Gliese91, and adopting V(AB)=9.587+-0.015 from Mermillid91, then V(A)=9.841, V(B)=11.291, i.e. within 0.01 mag of Gliese91. WDS lists mag(A)=9.930, mag(B)=11.41, which looks suspiciously close to V. plx=249.94+-1.87mas(vanLeeuwen07). HRD position: V(B)=11.291, plx=249.94 => Mv=13.28 and adopting BCv=-2.51 => Mbol=10.770, logL=-2.412. GJ 852A *dM4: Boeshaar85 Not listed by Kirkpatrick in the list of M dwarfs at www.dwarfarchives.org GJ 388 = AD Leo = Gam Leo C = BD+20_2465 = StKM 2-626 M2V: Stephenson86 *M3V: Kirkpatrick94,Henry94,Hawley97,Newton14(stan) M3.5V: Joy74(M3Ve),Bidelman85(M3.5) M4Vae: Keenan85(M4V),Keenan99 M4.5:V: JM53(non-stan) M5Ve: Vyssotsky56 Poor agreement among classifications, anywhere from M2 to M5. Henry94 - using Kirkpatrick91 standards - class it M3V. In Jacoby84 atlas as M4.5eV. Malkov12 lists it as a binary with period 26.5 years, a=0.1109", e=0.60. Leggett96 derives: flux = 3.12e-11 W/m^2, logL=-1.64, mbol=7.29, Mbol=8.85, BCv=-2.03, BC_K=2.68. V=9.421+-0.017(Mermilliod91), B-V=1.544+-0.009(Mermilliod91), U-B=1.075+-0.019(Mermilliod91), J=5.449+-0.027(2MASS), H=4.843+-0.020(2MASS,flag=E), Ks=4.593+-0.017(2MASS). V-Ks=4.828(Mermilliod91,2MASS). GJ 1005AB = LHS 1047 = 2MASS J00152799-1608008 *M4V: Bidelman85(M4),Henry94(M4VJ),Hawley97(M4 for A only),Henry02(M4VJ),Gaidos14 M3.5+(M4.5-M6.5V): Kirkpatrick94 All published types for unresolved pair are M4V. Hawley97 says its a 0.1" binary, with B being 0.5 mag fainter in V Reid04 says B is a M5.0V. V=11.530(Mermilliod91), B-V=1.740(Mermilliod91), U-B=1.260(Mermilliod91), J=7.215+-0.019(2MASS), H=6.712+-0.034(2MASS), Ks=6.390+-0.016(2MASS) => V-Ks = 11.53 - 6.39 = 5.14. 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. # Exemplars GJ 398 = LHS 2285 = RY Sex = G 44-27 = PM J10360+0507 = LP 550-177 = G 55-33 *M4Ve: Joy74(M4Ve), M4(Bidelman85), M4e(Lepine13), Newton14(near-IR), Gaidos14(M4e) All classifications are consistent with M4V. V=12.61(Mermilliod91), V=12.636+-0.012(Landolt92), B-V=1.560(Mermilliod91), B-V=1.586+-0.0106(Landolt92), U-B=1.088+-0.0106(Landolt92), U-B=1.120(Mermilliod91). V-R=1.185+-0.0046(Landolt92), R-I=1.526+-0.0039(Landolt92), V-I=2.714+-0.0032(Landolt92), J=8.463+-0.024(2MASS), H=7.875+-0.027(2MASS), Ks= 7.598+-0.023(2MASS). V-Ks =12.636 - 7.598 = 5.038. Teffs: 3140K(Lepine13), 3255K(Terrien15#1), 3295K(Terrien15#2), 3307K(Terrien15#3), 3328+-100K(Houdebine16), 3344+-63K(Muirhead18), 3367+-77K(Gaidos14), 3400K(Rajpurohit18), 3511+-120K(Newton15) => = 3328K. [Fe/H]=-0.02(Newton15#1), [Fe/H]=0.18(Newton15#2). GJ 1006 A = LHS 107 = EZ Psc = G 32-6 = L 1226-9 = LP 404-61 = HIP 1295 *M4Ve: Bidelman85(M4), Lepine13(M4.0), Gaidos14(M4e), Alonso-Floriano15(M4Ve) M3.6: Shkolnik09 Four published classifications are M4V. Binary companion B is 25" away. Another nonphysical companion C is 9.6" away. V=12.329+-0.018(Mermilliod91), B-V=1.441+-0.028(Mermilliod91), U-B=1.032+-0.077(Mermilliod91), J=7.875+-0.019, H=7.322+-0.018, Ks=7.087+-0.023. V-Ks = 12.329-7.087 = 5.242. Teffs: 3250K(Lepine13), 3298+-77K(Gaidos14) => = 3274K. GJ 609 = LHS 411 = L 1346-53 M3: Bidelman85 *M4V: Cowley82,Hawley97(M4),Lepine13(M4.0),Newton14(near-IR),Gaidos14(M4) V=12.554+-0.005(Mermilliod91), B-V=1.63(Mermilliod91), U-B=1.148+-0.059(Mermilliod91), J=8.132+-0.020(2MASS), H=7.648+-0.023(2MASS), Ks=7.369+-0.017(2MASS). V-Ks= 12.554 - 7.369 = 5.185. Teffs: 3005+-96K(Muirhead18), 3098+-50K(Houdebine12), 3100K(Lepine13), 3263+-100K(Houdebine16), 3300K(Rajpurohit18), 3310K(Passegger18), 3392+-102K(Newton15) => = 3263K. GJ 766A = Ross 165 = LHS 478 M4V: Bidelman85(M4),Hawley97,Tamazian06,Lepine13(M4),Gaidos14(M4) *M4V+M4V: Newton14 M4.5V: Joy74 2" binary (KUI 95 AB) with delta(mag) = 1.0, but Newton finds them to be both M4V. V=12.380(Mermilliod91), B-V=1.72(Mermilliod91), Ks=7.144(2MASS), V-Ks = 12.38 - 7.144 = 5.236. GJ 324B = 55 Cnc B = rho01 Cnc B = HD 75732B = LHS 2063 = LTT 12311 = NLTT 20418 = 2MASS J08524084+2818589 = Gaia DR2 704966762213039488 M1: Gaidos14 M3.5: Bidelman85 M3.6: Sebastian21(M3.6+-0.7) *M4V: Reid95,Kirkpatrick10,Rojas-Ayala12(near-IR),Lepine13(M4.16,adopts M4.0),Newton14(near-IR),Terrien15(M3.99),Mann15(M4.1),Houdebine17 M4.3V: Houdebine19(dM4.3) M4.5V: Alonso-Floriano15(Kunzentsov19?) Common proper motion companion to famous exoplanet host star 55 Cnc = rho01 Cnc = Copernicus, discovered by van Maanen (1918PASP...30..191V). Fairly good agreement on M4V type and metallicity is well-constrained in primary star. Probably a good metal-rich ([Fe/H]=+0.33) exemplar. V=13.148+-0.009(Mermilliod91), B-V=1.658+-0.004(Mermilliod91), U-B=1.200(Mermilliod91). J=8.560+-0.027(2MASS), H=7.933+-0.040(2MASS), Ks=7.666+-0.023(2MASS). G = 11.682962 0.002849(GaiaEDR3), E(BP/RP)=1.501, Bp-Rp=2.985494, Bp-G=1.718429, G-Rp=1.267065(GaiaEDR3). V-Ks = 13.148 - 7.666 = 5.482. plx=79.6560+-0.0475 mas(GaiaEDR3) => Mv = 12.654+-0.009(Mermilliod,GaiaEDR3), M_Ks = 7.172+-0.023(2MASS,GaiaEDR3), M_G = 11.189+-0.003. Teffs: 2939K(Moro-Martin15), 3071K(Kuznetsov19#2), 3072+-44K(Kuznetsov19#1), 3100K(Lepine13,Cifuente20), 3119+-103K(Kuznetsov19#3), 3130K(Morales08), 3166+-61K(Gaidos14,Mann15#1,Reiner20), 3200K(Rajpurohit18), 3203+-23K(Houdebine19), 3233+-100K(Houdebine16), 3237+-17K(Mann15#2), 3242+-68K(Muirhead18,Stassun19), 3253+-104K(Sebastian21), 3256+-29K(RojasAyala12), 3277+-61K(Gaidos14#2), 3280K(Veyette17), 3307K(Rajpurohit18), 3320+-51K(Schwitzer19), 3325K(Queiroz20), 3330+-90K(Lopez-Valdivia19), 3374K(Mugauer19), 3574K(GaiaDR2) => = 3240K. fbol = (0.16450+-0.00200)e-8 erg/s/cm2(Mann15) => mbol = 10.4621+-0.0132 mag(IAU2015 scale). median PASTEL [Fe/H] for 55 Cnc A is [Fe/H] = +0.33. BCv = mbol - V = 10.4621 - 13.148 = -2.6859. BC_Ks = 10.4621 - 7.666 = 2.7961. # Other Stars RECONS shows Barnard's Star (GJ 699; J1757+0441) as the nearest M4V star, followed by GJ 447 (J2305-3551). GJ 206 = Ross 42 = V998 Ori = StKM 2-413 M3V: Stephenson86 M4Ve: Joy74(M4Ve),Bidelman85(M4),Lepine13(M4),Gaidos14(M4e) *M4+M4.5: Shkolnik10 SB2. V=11.529+-0.013(Koen02), B-V=1.629+-0.018(Koen02), U-B=1.068+-0.038(Koen02), V-R=1.159+-0.009(Koen02), V-I=2.661+-0.008(Koen02).