M7V Kirkpatrick(in GrayCorbally09) call GJ 644C (= vB 8 = LHS 429) as the primary M7V standard. Boeshaar85 standard: GJ 644C (=VB 8) - M7V HenryKirkpatrick90 standard: GJ 644C (=VB 8) - M7V Kirkpatrick97 standard: GJ 644C (=VB 8) - M7V - pri. stan. Kirkpatrick99 standard: 2MASSW J1214+2027 - M7V Hawley02 standard: 2MASS J0055+2756 - M7V Henry02 standards: GJ 644C (=VB 8) - M7V LHS 3003 - M7V Henry04 standard: GJ 644C (=VB 8) - M7.0V - pri. stan. Kirkpatrick(GrayCorbally09): GJ 644C (=VB 8) - M7V - pri. stan. Kirkpatrick10 standard: GJ 644C (=VB 8) - M7V - opt./near-IR stan. Kirkpatrick16 standard: GJ 644C (=VB 8) - M7V RECONS list shows only VB 8 and LHS 3003 to be the only M7.0V stars in the nearest 100. Kirkpatrick12 lists only 3 M7V stars within 8 pc: VB 8, LHS 3003, and HR 753C (LFT217B). The first two are standards. ReinersBasri09 finds that the mean kinematic age of nearby M7-M9.5 stars is 3.1 Gyr. Skiff MK catalog shows LHS 429 (= GJ 644C) to be the only star classified as M7V by 3 or more authors. Kirkpatrick12 lists only 3 M7Vs within 8 pc: vB8, LHS 3003, and HR 753C ("M7:V"; based on colors) (M7V) = 1.68 ; Fitzgerald70 (B-V)(M7V) = 1.80 ; SchmidtKaler82 (M7V) = 1.84 ; Johnson66 (B-V)(M7V) = 2.10 ; Leggett92 "young disk" (B-V)(M7V) = 2.12 ; linear fit to Leggett92 (B-V=0.8367+0.2852*V-I, V-I=4.5) (B-V)(M7V) = 2.20 ; prim. stan. GJ 644 C => adopt (B-V)(M7V) = 2.12 [updated 7/5/2020] (M7V) = 1.40 ; Johnson66 (G-J)(M7V) = 3.482 ; Bentley18 (G-Ks)(M7V) = 4.406 ; Bentley18 (M7V) = 2.20 ; Johnson66 (V-R)(M7V) = 2.18 ; Bessell91 "old disk" (V-R)(M7V) = 2.10 +- 0.03 ; pri. stan. VB 8 (Dahn02) (V-R)(M7V) = 2.1: ; Bessell90 "old disk" (V-R)(M7V) = 2.06 ; non-standard LHS 292 (V-Ic)(M7V) = 4.56 ; pri. stan. VB 8 (V-Ic)(M7V) = 4.52 ; sec. stan. LHS 3003 (V-Ic)(M7V) = 4.50 ; trend Dieterich14 SpT vs. V-Ic (V-I)(M7V) = 4.50 ; Bessell91 "old disk" (V-I)(M7V) = 4.5: ; Bessell90 "old disk" (V-I)(M7V) = 4.45 ; Leggett92 "young disk" (V-Ic)(M7V) = 4.40 ; non-standard LHS 292 (M7V) = 4.20 ; Johnson66 => adopt (V-Ic)(M7V) = 4.50 [updated 7/4/2020] (R-I)(M7V) = 2.32 ; Bessell91 "old disk" (R-I)(M7V) = 2.341 ; N=6 M7Vs in Liebert06 (+-0.036 sem, +-0.089 rms) (R-I)(M7V) = 2.4: ; Bessell90 "old disk" => adopt (R-Ic)(M7V) = 2.34 => adopt (V-Rc)(M7V) = 2.18 (using R-I=2.34, V-I=4.52) (Bp-Rp)(M7V) = 3.64 ; Kiman19 (Bp-Rp)(M7V) = 4.0713 ; G_9-38B M7V (Bp-Rp)(M7V) = 4.5632 ; GAT_1370 M7V (Bp-Rp)(M7V) = 4.6254 ; LP_655-48 M7Ve (Bp-Rp)(M7V) = 4.651 ; M5-M8.5V color trend (Bp-Rp)(M7V) = 4.7539 ; GJ_644C/VB8 pri. stan. (Bp-Rp)(M7V) = 4.8024 ; LHS_3003 sec. stan. => adopt (Bp-Rp)(M7V) = 4.65 [updated 11/18/2020] (G-Rp)(M7V) = 1.47 ; Kiman19 (G-Rp)(M7V) = 1.4902 ; GAT_1370 M7V (G-Rp)(M7V) = 1.5169 ; GJ_644C/VB8 pri. stan. (G-Rp)(M7V) = 1.5223 ; G_9-38B M7V (G-Rp)(M7V) = 1.522 ; color trend M0V-M9V (G-Rp)(M7V) = 1.5314 ; LP_655-48 M7Ve (G-Rp)(M7V) = 1.5337 ; LHS_3003 sec. stan. => adopt (G-Rp)(M7V) = 1.52 [updated 11/18/2020] => adopt (Bp-G)(M7V) = 3.13 [updated 11/18/2020; Bp-Rp=4.65, G-Rp=1.52] (Bp-G)(M7V) = 2.2 ; Kiman19 (Bp-G)(M7V) = 3.2370 ; GJ_644C (Bp-G)(M7V) = 3.2687 ; LHS_3003 Note that for stars in SIMBAD with reported V and G magnitudes, there appears to be nice trend in G-V colors as f(SpT) through M6.5, but then things flatten out at M7V and beyond. I suspect this is due to the lack of reported Vmags. So we may want to rely more on the G-V colors for standards and exemplars with reported Vmags to get median G-V colors for these ultracool dwarfs. For M0-M6.5V, I find: G-V = -7.2910213128635681e-001 - 2.9463435852348743e-002*(SpT) - 6.3654819410898428e-002*(SpT^2) + 1.6296993908786160e-002*(SpT^3) - 1.9832979394373423e-003*(SpT^4) M_J(M7V) = 10.222 ; Reyle18 polynomial M_H(M7V) = 9.631 ; Reyle18 polynomial M_Ks(M7V) = 9.271 ; Reyle18 polynomial (G-Rp)(M7V) = 1.561 ; Reyle18 polynomial (G-J)(M7V) = 4.359 ; Reyle18 polynomial (J-Ks)(M7V) = 1.006 ; Reyle18 polynomial (M7V) = 5.20 ; Johnson66 (V-Ks)(M7V) = 7.194 ; exemplar LP 423-31 = NLTT 18549 (M7V) = 6.18 ; Johnson66 (V-Ks)(M7V) = 7.555 ; non-stan. Teegarden's star (V-Ks)(M7V) = 7.64 ; exemplar LHS 2645 (V-Ks)(M7V) = 7.75 ; trend fit to Dahn17 for M7V (V-Ks)(M7V) = 7.804 ; non-stan. LHS 292 = 7.85 ; Beuermann06 (V-K_CIT) = 7.85 ; Leggett92 "young disk" (V-Ks)(M7V) = 7.97 ; interp M6.5V(V-Ks=7.60)-M8V(V-Ks=8.70) (V-Ks)(M7V) = 7.984 ; prim. stan. VB 8 (V-Ks)(M7V) = 8.022 ; sec. stan. LHS 3003 (V-Ks)(M7V) = 8.24 ; non-stan. LP 655-48 (V-Ks)(M7V) = 8.32 ; exemplar LP 775-31 (V-K)(M7V) = 8.55 ; Bessell91 "old disk" => adopt (V-Ks)(M7V) = 8.00 *** [updated 12/27/2021] => adopt (V-J)(M7V) = 7.004 => adopt (V-H)(M7V) = 7.617 => adopt (J-H)(M7V) = 0.613 => adopt (J-Ks)(M7V) = 0.996 => adopt (I-Ks)(M7V) = 3.487 (G-Ks)(M7V) = 4.927 ; exemplar LP 423-31 = NLTT 18549 (G-Ks)(M7V) = 5.022 ; pri stan. VB 8 (G-Ks)(M7V) = 5.063 ; exemplar LHS 2645 (G-Ks)(M7V) = 5.155 ; sec. stan. LHS 3003 = LP 914-54 (G-Ks)(M7V) = 5.277 ; exemplar LP 775-31 => adopt (G-Ks) = 5.06 [updated 12/27/2021] (G-V)(M7V) = -3.0116 ; GJ_644C (G-V)(M7V) = -2.98 ; trinomial trend through late Ms (G-V)(M7V) = -2.94 ; (V-Ks)=8.00, (G-Ks)=5.06 (see below) (G-V)(M7V) = -2.8667 ; LHS_3003 (G-V)(M7V) = -2.226 ; median M7V d<60pc (N=25) => adopt (G-V)(M7V) = -2.94 [updated 12/27/2021] (M7V) = 0.37 ; Beuermann06 (H-Ks)(M7V) = 0.39 ; trend of Dieterich14 at V-Ks=8.0 => adopt (H-Ks)(M7V) = 0.39 (M7V) = 0.96 ; Beuermann06 (J-Ks)(M7V) = 0.96 (+-0.17 rms) ; Schmidt14 (J-Ks)(M7V) = 1.035 (+-0.005 sem, +-0.015 stdev) ; N=9 M7V Cruz03 (M7V) = 1.08 ; Faherty09 (g-r)(M7V) = 1.696 ; pri. stan. VB 8 (r-i)(M7V) = 2.50 (+-0.18 rms) ; West08 (r-i)(M7V) = 1.945 (+-0.05 rms) ; West05 fit for (V-Ic)=4.50 (r-i)(M7V) = -0.71 ; pri. stan. VB 8 [erroneous?] (i-z)(M7V) = 4.981 ; pri. stan. VB 8 [erroneous?] (i-z)(M7V) = 1.477 ; poly fit to d<75pc M dwarfs in SIMBAD for G-Ks=5.06 (i-z)(M7V) = 1.37 (+-0.09; rms) ; West08 (i-z)(M7V) = 1.17 (+-0.11; rms) ; Schmidt14 => adopt (i-z)(M7V) = 1.48 [updated 12/28/2021] (z-J)(M7V) = 1.973 ; pri. stan. VB 8 (z-J)(M7V) = 1.952 (+-0.053 rms) ; poly fit to SIMBAD d<50pc M dwarfs for G-Ks=5.06 (z-J)(M7V) = 1.85 (+-0.10; rms) ; West08 (z-J)(M7V) = 1.72 (+-0.13; rms) ; Schmidt14 => adopt (z-J)(M7V) = 1.96 [updated 12/27/2021] (i-J)(M7V) = 2.89 (+-0.21 rms) ; Schmidt14 (i-Ks)(M7V) = 3.86 (+-0.25 rms) ; Schmidt14 (J-H)(M7V) = 0.61 (+-0.14 rms) ; Schmidt14 (J-H)(M7V) = 0.635 (+-0.009 sem, +-0.029 rms) ; N=9 M7V Cruz03 (H-Ks)(M7V) = 0.34 (+-0.17 rms) ; Schmdit14 (H-Ks)(M7V) = 0.397 (+-0.012 sem, +-0.034 rms) ; N=9 M7V Cruz03 (Ks-L')(M7V) = 0.318 ; Dupuy12 polynomial (Ks-W1)(M7V) = 0.18 (+-0.14 rms) ; Schmidt14 (Ks-W1)(M7V) = 0.197 ; pri. stan. VB8/allWISE (Ks-W1)(M7V) = 0.207 ; Bentley18 (Ks-W1)(M7V) = 0.210 ; Best18 (Ks-W1)(M7V) = 0.210 ; sec. stan. LHS3003/WISE (Ks-W1)(M7V) = 0.228 ; pri. stan. VB8/WISE (Ks-W1)(M7V) = 0.234 ; fit to Winters15 data for V-Ks=8.00 (Ks-W1)(M7V) = 0.236 ; Dupuy12 median (N=5, d<50pc) (Ks-W1)(M7V) = 0.242 ; sec. stan. LHS3003/WISE (Ks-W1)(M7V) = 0.244 ; Avenhaus12 for V-Ks=8.00 (Ks-W1)(M7V) = 0.250 ; Dupuy12 trend => adopt (Ks-W1)(M7V) = 0.24 [updated 12/29/2019] (Ks-W2)(M7V) = 0.432 ; Bentley18 (W1-W2)(M7V) = 0.20 (+-0.07 rms) ; Schmidt14 (W1-W2)(M7V) = 0.225 ; Bentley18 (W2-W3)(M7V) = 0.29 (+-0.18 rms) ; Schmidt14 Mv(M7V) = 14.3 ; Schmidt-Kaler82 Mv(M7V) = 17.47 ; non-stan. LHS 292 Mv(M7V) = 17.655 ; EEM fit to Reid CNS3 data (V=K=8.00) Mv(M7V) = 17.685 ; Dieterich14 calibration for V-Ks=8.00 Mv(M7V) = 17.69 ; sec. stan. LHS 3003 Mv(M7V) = 17.70 ; M_Ks=9.70, V-Ks=8.00 Mv(M7V) = 17.745 ; prim. stan. VB 8 Mv(M7V) = 17.723 ; EEM fit to Winters+2015 data (V-K=8.00) Mv(M7V) = 17.76 ; Kirkpatrick94 Mv(M7V) = 17.782 ; Finch14 calibration for V-Ks=8.00 Mv(M7V) = 17.9 ; (see Fig. 9 of Riedel+2010 for V-K=8.053) Mv(M7V) = 18.08 ; Henry94 => adopt Mv(M7V) = 17.70 mag [updated 12/10/2020] (M_Ks=9.70, V-Ks=8.00) => adopt M_G(M7V) = 14.72 mag [updated 12/10/2020] (Mv=17.70, G-V=-2.98) => adopt M_Ks(M7V) = 9.70 mag [updated 12/10/2020] (Mv=17.70, V-Ks=8.00) M_G(M7V) = 12.1683 ; G 122-49 M_G(M7V) = 12.7612 ; G 100-28 M_G(M7V) = 13.0542 ; LP 35-347 M_G(M7V) = 13.54 ; Kiman19 M_G(M7V) = 13.6322 ; 2MASS J03304890+5413551 M_G(M7V) = 13.6456 ; LP 245-10 M_G(M7V) = 13.79 ; median nearest 10 M7s in SIMBAD M_G(M7V) = 13.9431 ; G 9-38B M_G(M7V) = 14.212 ; Reyle18 polynomial M_G(M7V) = 14.3583 ; NAME Teegarden's Star M_G(M7V) = 14.72 ; Mv=17.70, G-V=-2.98 M_G(M7V) = 14.767 ; trend SIMBAD d<10pc sample M_G(M7V) = 14.7729 ; pri. stan. VB 8 M_G(M7V) = 14.8397 ; sec. stan. LP 914-54 M_G(M7V) = 14.9078 ; WISEA J051019.92+271355.3 M_Ks(M7V) = 9.782 ; Finch14 calibration for V-K=8.00 M_Ks(M7V) = 9.751 ; pri. stan. VB 8 M_Ks(M7V) = 9.723 ; EEM fit to Dieterich+14 data V-K=8.00 M_Ks(M7V) = 9.70 ; Mv=17.70, V-Ks=8.00 M_Ks(M7V) = 9.685 ; sec. stan. LHS 3003 M_Ks(M7V) = 9.685 ; Dieterich14 calibration for V-K=8.00 M_Ks(M7V) = 9.655 ; EEM fit to Reid CNS3 data for V-K=8.00 M_Ks(M7V) = 9.62 ; non-stan. LHS 292 M_Ks(M7V) = 9.57 ; Dupuy12 polynomial M_Ks(M7V) = 9.42 ; Dupuy12 mean M_Ks(M7V) = 9.9225 ; exemplar LP 775-31 Teff(M7V) = 2940 K ; Schmidt-Kaler82 Teff(M7V) = 2900 K ; Rajpurohit18 (mean for N=3 M7Vs) Teff(M7V) = 2850 K ; Johnson66 Teff(M7V) = 2846 K ; Dupuy17(SaumonMarley08 models scale) Teff(M7V) = 2809 K ; Dupuy17(Lyon models scale) Teff(M7V) = 2758 K ; RojasAyala12(mean N=5 M7V stars) Teff(M7V) = 2700 K ; Rajpurohit13(N=3) Teff(M7V) = 2700 K ; Cifuentes20 for CARMENES M7V(N=5) Teff(M7V) = 2700 K ; pri. stan. VB8 (see below) Teff(M7V) = 2683 K ; Filippazzo15 calibration (M6V-T9V) Teff(M7V) = 2680 K ; using Mann15 Rad vs. M_K=9.7, [Fe/H]=0.0 for logL=-3.188 Teff(M7V) = 2676 K ; Dahn02 average for LHS 429 & LHS 3003 Teff(M7V) = 2660 K ; empirical L-R relation, for logL=-3.188 Teff(M7V) = 2626 K ; EEM N=18 Teffs Teff(M7V) = 2621 K ; Golimowski04 Teff(M7V) = 2619 K ; LHS 2351 (Dieterich14) Teff(M7V) = 2600 K ; Bessell91 "old disk" Teff(M7V) = 2580 K ; sec. stan. LHS3003 (median Teff) Teff(M7V) = 2581 K ; sec. stan. LHS 3003 (Dieterich14) Teff(M7V) = 2532 K ; LP 775-031 (Dieterich14) Teff(M7V) = 2508 K ; CE 303 (Dieterich14) Teff(M7V) = 2466 K ; SIPS J1607-0442 (Dieterich14) Teff(M7V) = 2400 K ; Leggett92 "young disk" => adopt Teff(M7V) = 2680 K (logT = 3.428) [updated 4/9/2020] [Note: the colors and abs mags for the pri. & sec. standard are so similar, probably best to take their approximate average; 10/18/2019] BCv(M7V) = -3.33 mag ; Schmidt-Kaler82(BCv=-3.46 + 0.13 offset) BCv(M7V) = -4.27 mag ; EEM fit to Casagrande08 data(Teff=2500K) BCv(M7V) = -4.93 mag ; Mbol=12.84, Mv=17.77 BCv(M7V) = -4.985 mag ; pri. stan. VB 8 (derived using Dahn02) BCv(M7V) = -4.99 mag ; BC_K=3.01, V-Ks=8.00 BCv(M7V) = -5.07 mag ; sec. stan. LHS 3003 (Leggett01) BCv(M7V) = -5.50 mag ; Bessell91("old disk"; BCv = (V-I)-BC_I) => adopt BCv(M7V) = -4.99 mag [updated 11/3/2019] BC_Ks(M7V)= 2.791 ; pri. stan. VB 8 (see below) BC_Ks(M7V)= 2.827 ; sec. stan. LHS 3003 (see below,Pecaut13) BC_Ks(M7V)= 2.91 ; Schmidt14 (rms = 0.08) BC_K(M7V) = 2.920 ; Leggett01 polynomial for J-K=0.999 BC_Ks(M7V)= 2.99 ; trend for mid/late M dwarfs BC_K(M7V) = 3.009 ; pri. stan. VB 8 (Leggett01, IAU scale) BC_K(M7V) = 3.012 ; Leggett01 polynomial for I-K=3.509 BC_K(M7V) = 3.014 ; pri. stan. VB 8 (derived using Dahn02) BC_K(M7V) = 3.03 ; sec. stan. LHS 3003 (Leggett96,Leggett01) BC_K(M7V) = 3.049 ; pri. stan. LHS 429/Dahn02/BC_J=2.05, assume J-Ks=0.999 BC_K(M7V) = 3.05 ; sec. stan. LHS 3003 (Golimowski04) BC_K(M7V) = 3.056 ; Golimowski04(for SpT) => adopt BC_K = 3.01 mag [updated 12/10/2020] logL(M7V) = -3.459+-0.025 ; SIP 1632-0631 (Dieterich14) logL(M7V) = -3.309+-0.018 ; CE303 (Dieterich14) logL(M7V) = -3.3033+-0.012 ; LP 775-031 (Dieterich14) logL(M7V) = -3.28 ; sec. stan. LHS 3003 (Leggett01) logL(M7V) = -3.28+-0.03 ; sec. stan. LHS 3003 (Golimowski04) logL(M7V) = -3.274 ; sec. stan. LHS 3003 (Dahn02) Mbol = 12.94 logL(M7V) = -3.266+-0.013 ; sec. stan. LHS 3003 (Dieterich14) logL(M7V) = -3.218+-0.056 ; LHS 2351 (Dieterich14) logL(M7V) = -3.214+-0.007 ; pri. stan. GJ644C/VB8 (Dieterich14) logL(M7V) = -3.206 ; pri. stan. LHS 429/vB8 (Dahn02) Mbol = 12.77 logL(M7V) = -3.188 ; M_Ks=9.70, BC_K=3.01 => Mbol = 12.710 => adopt logL(M7V) = -3.188 dex [updated 12/10/2020] => adopt Mbol(M7V) = 12.710 mag [updated 12/10/2020] Mass(M7V) = 0.098 Msun ; M_Ks=9.7 => EEM fit to M_Ks vs. Msun for Dupuy10 data Mass(M7V) = 0.093 Msun ; M_Ks=9.7 => Benedict16 calibration Mass(M7V) = 0.0901 Msun ; M_Ks=9.7 => Mann18 calib. => adopt Mass(M7V) = 0.090 Msun [updated 11/15/2021] Rad(M7V) = 0.1235 Rsun ; Rabus19 trend for Teff=2660K Rad(M7V) = 0.1200 Rsun ; logL=-3.188, Teff=2660K Rad(M7V) = 0.1181 Rsun ; Mann15 trend M_Ks=9.7, [Fe/H]=0.0 Rad(M7V) = 0.118 Rsun ; median of 6 M7V stars (Dieterich14) Rad(M7V) = 0.1129 Rsun ; pri. stan. vB8/LHS429 (Dahn02) Rad(M7V) = 0.1096 Rsun ; sec. stan. LHS 3003 (Dahn02) => adopt Radius(M7V) = 0.120 Rsun [updated 4/4/2009] # No Standard Keenan85 and Houk75 do not list M7V standards. Skiff08 does not flag any stars as M7V MK standards. # Primary Standard VB 8 = GJ 644 C = LHS 429 *M7V: Boeshaar85(dM7),GiampapaLiebert86,HenryKirpatrick90,Kirkpatrick91(pri),Henry97,Kirkpatrick97(stan),Henry02,Henry04,Kirkpatrick(GrayCorbally09) M6.5e: Bessell91 M6.3: Reid05 Not listed in Hawley97 or Reid04. Plx=154.5+-0.7 mas (Dahn02 => m-M=-0.94+-0.01), B-V=2.20(Leggett92), V-I=4.56 (Leggett92), V=16.80 (Leggett92), V=16.81+-0.02(Dahn02), V=16.78(Henry04), Rc=14.60(Henry04), Rc=14.71+-0.02(Dahn02), V-Rc=2.10+-0.03(Dahn02) Ic=12.28+-0.02(Dahn02), Ic=12.18(Henry04), K_CIT=8.82(Leggett92), K=8.83+-0.02(Dahn02), J=9.776+-0.029(2MASS), H=9.201+-0.024(2MASS0, Ks=8.816+-0.023(2MASS). WISE: W1=8.588+-0.023, W2=8.365+-0.021, W3=8.132+-0.022. allWISE: W1=8.619+-0.023, W2=8.393+-0.020, W3=8.127+-0.023. Ks-W1=0.228(WISE), Ks-W1=0.197(allWISE). (V-Ks)=7.984 (Leggett92,2MASS), K-L'(MKO) = 0.47 (Leggett92), Mv=17.745+-0.014(Leggett92, Reid05), M_Ks=9.761+-0.025(Leggett92, Reid05). Dahn02 Vmag and plx => Mv = 17.755+-0.022. Dahn02 lists: M_J=10.72, BC_J=2.05, Mbol=12.77, R=0.1129Rsun, so one derives mbol = 11.83, BCv = 11.83 - 16.81 = -4.98, BC_K = 11.83 - 8.816 = 3.014. Mv - Mbol = 17.755 - 12.77 = BCv = -4.985. mbol=11.607+-0.036(JHK=>Pecaut13), BC_Ks=11.607-8.816=2.791. Leggett01: fbol = 4.69e-13 W/m2 => mbol = 11.825 => BC_Ks = 11.825 - 8.816 = 3.009 (IAU2015 scale). Teffs: 2300K(Leggett00*), 2400K(Casagrande08*), 2425K(Jenkins09*), 2500K(ReidHawley05*), 2611+-43K(Dieterich14), 2700K+-60K (Mann15), 2700K(Rajpurohit13), 2707+-63K(Dahn02*), 2708K(Stelzer13), 2727K(RojasAyala12*), 2850K(Lyubchik12*,average) => adopt Teff = 2700K. (G-Ks)=5.022, M_G=14.773, M_Ks=9.751. SDSSDR9 photometry listed in SIMBAD: (g-r) = 17.716 - 16.02 = 1.696. (r-i) = 16.020 - 16.730 = -0.71. (i-z) = 16.730 - 11.749 = 4.981. (z-J) = 11.749 - 9.776 = 1.973. # Secondary Standard LHS 3003 = LP 914-54 = GJ 3877B *M7V: Kirkpatrick95,Leggett01,Geballe02,Henry02,Hawley97("M7c"),Henry04 M6.5: Bessell91 plx=157.0+-3.0 mas(Dahn02 => m-M=-0.98+-0.04), plx=157.8+-5.1 mas(Reid02), plx=140.58+-0.54(Weinberger16), B-V=1.34(Gliese91), V=17.05(Gliese91, Leggett92, Leggett01, Reid02), V=17.05+-0.03(Dahn02), V=16.95(Hosey15), Rc=14.90(Hosey15), Ic=12.53(Hosey15), I=12.53(Leggett01), V-I=4.52(Leggett01,Reid02), J=9.965+-0.026(2MASS), H=9.315+-0.022(2MASS), Ks=8.928+-0.027(2MASS). WISE: W1=8.686+-0.022, W2=8.487+-0.020, W3=8.274+-0.023. allWISE: W1=8.718+-0.024, W2=8.505+-0.019, W3=8.273+-0.025. (Ks-W1)=0.242(WISE), (Ks-W1)=0.210(allWISE). [3.6]=8.47+-0.02, [4.5]=8.49+-0.01, [5.8]=8.39+-0.02, [8.0]=8.36+-0.01 (Patten06). (V-Ks)=8.022 (Hosey15,2MASS), Mv=17.69(Hosey15,Weinberger16), M_Ks=9.668+-0.028(2MASS,Weinberger16). Leggett01 lists: M-m=0.97, V-I=4.52, I=12.53, I-J=2.51, J-H=0.65, H-K=0.42, K=8.95, K-L'=0.52 (IR bands on UKIRT-IRCAM3 system), flux = 4.14e-13 W/m^2, mbol = 11.98, BC_K=3.03, logL=-3.28. The Leggett01 photometry (V=17.05, mbol=11.98) is consistent with BCv=-5.07. Dahn02 lists: M_J=10.91, BC_J=2.03, Mbol=12.94, R=0.1096Rsun => logL=-3.274, Teffs: 2200K(Leggett01), 2350K(Casagrande08), 2393K(Jenkins09), 2581+-17K(Dieterich14), 2600K(Golimowski04), 2645+-70K(Dahn02), 2700K(Mohanty03,Loyd14) => median Teff = 2580K. mbol = 11.755+-0.042(JHK=>Pecaut13), BC_Ks = mbol - Ks = 11.755-8.928 = 2.827. (G-Ks)=5.155, M_G=14.840, M_Ks=9.685. # Deprecated Standard 2MASS J0055+2756 = 2MASS J00553841+2756523 = 2MASSW J0055384+275652 M7V: Kirkpatrick99(non-standard),Hawley02(stan) Only 4 SIMBAD references 1999-2004. Estimated distance 94 pc. J=15.73, H=14.86, Ks=14.46 (2MASS, Kirkpatrick99). V=18.983(Qi15,photographic). I do not list the star as a standard as it is poorly characterized for now. # Exemplars LP 423-31 = NLTT 18549 = LSPM J0752+1612 = 2MASS J07522390+1612157 *M7Ve: Cruz03,Reid03,Reiners09,Gagne14(optical),West15(M7) M6V: Gagne14(M6,near-IR),Newton14(near-IR) V=17.04(Winters19), R=15.32(Winters19), I=13.21(Winters19), J=10.879+-0.022(2MASS), H=10.197+-0.022(2MASS), Ks=9.846+-0.019(2MASS), V-Ks = 17.04 - 9.846 = 7.194. (G-Ks) = 4.927, M_G=13.3915, M_Ks=8.46451, plx=52.93mas(SIMBAD), G=14.773, Ks=9.846 LP 775-31 = 2MASS J04351612-1606574 M6V: Cruz02(Cruz03 pointed out change) *M7V: Cruz03,Henry04(M7Ve),Cruz07,Schmidt07,Reiners09,Deshpande12,Deiterich14 M7.5e: Lodieu05 M8Ve: McCaughrean02,Reid03(M8) V-Ks = 8.32(Hosey15). G=14.6290+-0.0006(GaiaDR2). J=10.406+-0.026(2MASS), H=9.779+-0.026(2MASS), Ks=9.352+-0.021(2MASS). plx=94.4906+-0.2523mas(GaiaDR2), plx=94.3054+-0.2099mas(GaiaEDR3). G-Ks = 14.6290 - 9.352 = 5.277. M_Ks = 9.225+-0.022(2MASS,GaiaEDR3). LHS 2645 = NLTT 32206 = LSPM J1253+4034 = SDSS J125312.49+403400.6 = 2MASS J12531240+4034038 M6.4+-1.0: Sebastian01(SPECULOOS) *M7Ve: Kirkpatrick93(M7),ReidGizis05(M7Ve),West08(M7e),Jenkins09(M7.0),West11(M7e) M7.5: Kirkpatrick95(M7.5V),Kirkpatrick10 V=18.43(Salim03), V=18.80(Jenkins09), V=18.90(Lepine05), J=12.185+-0.019(2MASS), H=11.545+-0.022(2MASS), Ks=11.162+-0.019(2MASS). V-Ks ~ 18.80 - 11.162 = 7.638. plx=47.1353+-0.0953mas(GaiaDR2), G=16.2253+-0.0006(GaiaDR2). G-Ks = 16.2253 - 11.162 = 5.063. LHS 3002 = LP 441-34 LP 220-13 # Other Stars LP 655-48 = 2MASS J04402325-0530082 = DENIS-P J0440231-053009 M6.0: Cruz02,Gagne14,Alonso-Floriano15 M6.5Ve: Reidel14 *M7V: Cruz03,Henry04(M7Ve),Schmidt07,Cruz07,Despande12,Crossfield14 M7.5Ve: McCaughrean02,Lodieu05,Crifo05,Phan-Bao17 Not great agreement on subtype, but median subtype is ~M7.0V. V=17.86(Casagrande08), V-Rc=1.910(Casagrande08), V-Ic=4.230(Casagrande08). plx=102.30+-1.02mas(Weinberger16). V-Ks=8.24(Hosey15). Teffs: 2250+-118K(Casagrande08), 2600K(Rajpurohit13). mbol = 12.845(Casagrande08) LP 402-58 = 2MASSI J2336439+215338 M7.0V: Gizis02,Rice10 Teff=2879K(Rice10) LHS 292 = GJ 3622 = PM I10482-1120 M6.0: Dieterich14 M6.5: Morin10,Stelzer13 *M7.0V: Henry04,Gaidos14(M7) V=15.73(Henry04), V=15.78+-0.057(Dieterich14), Rc=13.67(Henry04), Rc=13.63+-0.002(Dieterich14), V-Rc=2.06(Henry04), Ic=11.33(Henry04), Ic=11.25+-0.025(Dieterich14), V-Ic=4.40(Henry04), J=8.857+-0.021(2M), H=8.263+-0.036(2M), Ks=7.926+-0.033(2M). V-Ks = 15.73-7.926 =7.804. plx=218.10+-0.60mas(Weinberger16). Mv=17.47+-0.06(Dieterich14, Weinberger16), M_Ks=9.62+-0.03(2MASS,Weinberger16). No companion (Rodriguez15). Teffs: 2739+-60K(Gaidos14), 2784K(Stelzer13). Mass = 0.09Msun(Morin10), 0.14Msun(Gaidos14). GJ 105C = HR 753B = G 73-70B = WDS J02361+0653B *M7:V: Kirkpatrick12(based on colors) M6V: JM53(non-stan.,"dM6") Close companion (sep=1.7") to bright K3V standard star HD 16160 (HR 753), P=61yr, e=0.67, and other component GJ 105B is 165" away (M3V). No spectral types in Skiff compendium. WDS SpT entries appear to be in error (11/1/2019; currently lists comp 105C (GKI 1 B = WDS J02361+0653B) as "M4.5V" while PLQ 32 C (WDS J02361+0653C) situated 164" away is "M7V". CTI 115638.5+280002 = 2MASS J11571691+2755489 *M7V: Kirkpatrick93,Martin94,Kirkpatrick94 No Vmag or plx. Ks=13.335+-0.027. Teegarden's Star = SO 025300.5+165258 = 2MASS J02530084+1652532 M6V: Henry06(table,Kirkpatrick12),Kesselli19(dM6) M6.5V: Teegarden03,Dieterich14(citing Henry06) M6.6V: Sebastian21(M6.6+-1.0) *M7.0V: Henry04,Henry06(text),Burgasser08,Lepine13,Gaidos14,Mann15,Alonso-Floriano15,Jeffers18,Rajpurohit18 M7.5\beta: Gagne15 M7.8V: Houdebine19(dM7.8) M8V: Newton14(near-IR) M8/9V: Newton14(near-IR) Henry06 lists M6V in table, M7.0V in text, and Dieterich14 lists M6.5 and cites Henry06! Note that its V-Ks color (7.555) is almost identical to that of the M6.5V primary standard GJ 1111 (V-Ks=7.564), and clearly bluer than the two best M7V standards (VB8 [7.984] and LHS3003 [8.022]). However most references give M7.0V and some of the near-IR surveys give M7.5 or M8. Its Mv value is typical for M6.5V but its M_Ks value is spot on for M7V. It has high Vtan (93 km/s;GaiaEDR3) and RV(63+-5 km/s; Newton14) for Stot=112 km/s; GCNS lists U,V,W = -64.152, -73.058, -54.423 km/s, and for this velocity using Galactic pop model from Bensby14, I estimate kinematic probabilities: P(think)=5.9%, P(thick)=58.4%, P(halo)=0.07%, P(Hercules)=35.7%. So the star is likely either a thick disk or Hercules stream star. plx=260.63+-2.69(Henry06), plx=260.9884+-0.0934mas(GaiaEDR3). D=3.84+-0.04pc(Henry06). V=15.14(Henry06), Rc=13.03(Henry06), Ic=10.65(Henry06), J=8.394+-0.027(2MASS), H=7.883+-0.040(2MASS), Ks=7.585+-0.046(2MASS), Mv=17.22(Henry06,GaiaEDR3), M_Ks=9.668+-0.046(2MASS,GaiaEDR3). V-Ks=15.14-7.585=7.555(Henry06,2MASS). Teff: 2700+-60K(Gaidos14). M=0.14Msun(Gaidos14). [Fe/H]=-0.55+-0.17(RojasAyala12#2), [M/H]=-0.38+-0.12(RojasAyala12#1), [Fe/H]=-0.42+-0.14(Newton14), [Fe/H]=-0.19+-0.16(Schweitzer19)... but [M/H]=+0.30(Rajpurohit18). # V-K vs. Mv V-Ks Mv M_Ks 7.984 17.745 9.761+-0.025 VB_8 (pri. stan.) 8.022 17.69 9.668+-0.028 LHS3003 (sec. stan)