\begin{table}%t3 \caption{\label{find}Experimental oscillator strengths (log~$gf$) in \ion{Nb}{ii} sorted by air wavelengths.} %\centering \par \begin{tabular}{llrr} \hline \hline \noalign{\smallskip} $\lambda_{\rm air}$ & $\sigma$ & Lower level & Log($gf$) \\ (\AA{}) & (cm$^{-1}$) & (cm$^{-1}$) & \\ \hline 2242.5800 & 44 577.650 & 1224.823 & $-$1.20 \\ 2263.3106 & 44 169.386 & 801.326 & $-$1.89 \\ 2265.6748 & 44 123.277 & 801.326 & $-$1.37 \\ 2285.2235 & 43 745.889 & 1224.823 & $-$1.14 \\ 2291.3844 & 43 628.304 & 438.361 & $-$2.29 \\ 2300.2897 & 43 459.407 & 158.984 & $-$2.12 \\ 2300.8551 & 43 448.717 & 438.361 & $-$1.96 \\ 2315.1745 & 43 180.030 & 438.361 & $-$1.63 \\ 2320.2400 & 43 085.752 & 801.326 & $-$1.57 \\ 2332.8990 & 42 851.977 & 438.361 & $-$1.93 \\ 2334.8014 & 42 817.065 & 801.326 & $-$1.75 \\ 2343.2745 & 42 662.255 & 1224.823 & $-$1.92 \\ 2372.7316 & 42 132.646 & 0.000 & $-$2.31 \\ 2381.7200 & 41 973.662 & 158.984 & $-$2.22 \\ 2514.3531 & 39 759.692 & 801.326 & $-$1.76 \\ 2541.4244 & 39 336.195 & 1224.823 & $-$1.02 \\ 2566.0734 & 38 958.386 & 9812.452 & $-$1.41 \\ 2590.9428 & 38 584.448 & 10186.390 & +0.17 \\ 2641.0561 & 37 852.364 & 10918.474 & $-$0.86 \\ 2646.253$^{\star}$ &37 778.026 &438.361&$-$0.55 \\ 2656.075$^{\star}$ &37 638.332 &158.984&$-$0.61 \\ 2666.590$^{\star}$ &37 489.926 &801.326&$-$0.79 \\ 2667.1467 & 37 482.100 & 8320.373 & $-$0.59 \\ 2667.291$^{\star}$ &37 480.076 &0.000&$-$0.77 \\ 2671.6567 & 37 418.838 & 7505.765 & $-$1.30 \\ 2671.926$^{\star}$ &37 415.061 &801.326&$-$0.33 \\ 2675.939$^{\star}$ &37 358.955 &438.361&$-$0.73 \\ 2678.654$^{\star}$ &37 321.092 &158.984&$-$1.56 \\ 2691.770$^{\star}$ &37 139.258 &158.984&$-$0.79 \\ 2697.059$^{\star}$ &37 066.429 &1224.823&$+$0.06 \\ 2698.858$^{\star}$ &37 041.715 &438.361&$-$0.56 \\ 2700.1527 & 37 023.959 & 7900.644 & $-$0.68 \\ 2700.5523 & 37 018.457 & 3542.561 & $-$1.27 \\ 2702.194$^{\star}$ &36 995.990 &801.326&$-$0.51 \\ 2702.517$^{\star}$ &36 991.564 &1224.823&$-$0.75 \\ 2706.397$^{\star}$ &36 938.540 &438.361&$-$1.25 \\ 2716.306$^{\star}$ &36 803.790 &158.984&$-$1.18 \\ 2716.622$^{\star}$ &36 799.513 &1224.823&$-$0.24 \\ 2721.630$^{\star}$ &36 731.805 &0.000&$-$1.42 \\ 2721.982$^{\star}$ &36 727.056 &801.326&$-$0.29 \\ 2729.5123 & 36 625.754 & 7261.324 & $-$1.77 \\ 2733.256$^{\star}$ &36 575.575 &801.326&$-$0.60 \\ 2733.462$^{\star}$ &36 572.821 &158.984&$-$1.05 \\ 2734.3521 & 36 560.900 & 7505.765 & $-$1.19 \\ 2737.085$^{\star}$ &36 524.413 &438.361&$-$0.87 \\ 2745.3118 & 36 414.981 & 4146.037 & $-$0.86 \\ 2747.3562 & 36 387.869 & 7261.324 & $-$0.94 \\ 2749.6848 & 36 357.067 & 7261.324 & $-$1.32 \\ 2754.5496 & 36 292.869 & 9509.604 & $-$0.74 \\ 2765.9299 & 36 143.428 & 7505.765 & $-$1.45 \\ 2768.124$^{\star}$ &36 114.877 &438.361&$-$0.50 \\ 2780.235$^{\star}$ &35 957.568 &4146.037&$-$0.40 \\ 2793.041$^{\star}$ &35 792.709 &3542.561&$-$0.71 \\ 2793.6766 & 35 784.573 & 7505.765 & $-$1.43 \\ 2798.9044 & 35 717.747 & 7900.644 & $-$1.03 \\ 2810.7918 & 35 566.705 & 8320.373 & $-$0.69 \\ 2827.075$^{\star}$ &35 361.838 &158.984&$-$0.83 \\ 2829.750$^{\star}$ &35 328.415 &1224.823&$-$1.55 \\ 2841.143$^{\star}$ &35 186.758 &3029.629&$-$0.69 \\ 2842.643$^{\star}$ &35 168.184 &2629.132&$-$0.59 \\ 2846.279$^{\star}$ &35 123.260 &2356.816&$-$0.73 \\ 2861.092$^{\star}$ &34 941.426 &2356.816&$-$0.68 \\ 2865.609$^{\star}$ &34 886.354 &0.000&$-$1.18 \\ 2866.8425 & 34 871.322 & 7261.324 & $-$2.13 \\ \hline 2887.0836 & 34 626.881 & 7505.765 & $-$1.52 \\ 2917.0516 & 34 271.176 & 10653.427 & $-$0.66 \\ 2956.8884 & 33 809.499 & 7900.644 & $-$1.29 \\ 2868.521$^{\star}$ &34 850.944 &2629.132&$-$0.37 \\ 2875.390$^{\star}$ &34 767.687 &3029.629&$-$0.17 \\ 2877.038$^{\star}$ &34 747.769 &2629.132&$-$0.39 \\ 2883.174$^{\star}$ &34 673.826 &3542.561&$-$0.04 \\ 2888.829$^{\star}$ &34 605.958 &2356.816&$-$0.59 \\ 2897.806$^{\star}$ &34 498.753 &3029.629&$-$0.37 \\ 2899.233$^{\star}$ &34 481.775 &3542.561&$-$0.34 \\ 2908.240$^{\star}$ &34 374.989 &2356.816&$-$0.40 \\ 2910.587$^{\star}$ &34 347.272 &3029.629&$-$0.16 \\ 2911.742$^{\star}$ &34 333.642 &2629.132&$-$0.28 \\ 2927.811$^{\star}$ &34 145.215 &4146.037&$+$0.16 \\ 2931.464$^{\star}$ &34 102.673 &2629.132&$-$0.92 \\ 2941.543$^{\star}$ &33 985.821 &3542.561&$-$0.05 \\ 2946.895$^{\star}$ &33 924.106 &2629.132&$-$1.00 \\ 2950.880$^{\star}$ &33 878.299 &4146.037&$+$0.24 \\ 2972.5710 & 33 631.122 & 11339.590 & $+$0.32 \\ 2980.7132 & 33 539.252 & 12263.221 & $-$0.29 \\ 2982.102$^{\star}$ &33 523.609 &3029.629&$-$0.85 \\ 2991.9493 & 33 413.238 & 10653.427 & $-$0.76 \\ 2994.722$^{\star}$ &33 382.345 &4146.037&$-$0.29 \\ 3014.439$^{\star}$ &33 164.006 &2356.816&$-$1.61 \\ 3024.7316 & 33 051.241 & 10835.837 & $-$0.18 \\ 3028.441$^{\star}$ &33 010.677 &3542.561&$-$0.20 \\ 3029.7413 & 32 996.508 & 12805.965 & $-$0.74 \\ 3029.8088 & 32 995.766 & 10653.427 & $-$1.11 \\ 3032.6351 & 32 964.964 & 10653.427 & $-$1.26 \\ 3039.397$^{\star}$ &32 891.690 &2629.132&$-$1.26 \\ 3049.5039 & 32 782.554 & 10835.837 & $-$1.04 \\ 3055.5159 & 32 718.166 & 16052.672 & $-$0.39 \\ 3063.1193 & 32 636.911 & 10653.427 & $-$0.91 \\ 3071.5463 & 32 547.488 & 11339.590 & $-$0.29 \\ 3073.236$^{\star}$ &32 529.538 &2356.816&$-$1.19 \\ 3074.270$^{\star}$ &32 518.595 &7261.324&$-$1.69 \\ 3076.863$^{\star}$ &32 491.193 &3029.629&$-$0.55 \\ 3080.3475 & 32 454.501 & 10835.837 & $-$0.48 \\ 3094.174$^{\star}$ &32 309.420 &4146.037&$+$0.56 \\ 3097.1160 & 32 278.801 & 11339.590 & $-$0.84 \\ 3099.181$^{\star}$ &32 257.222 &2629.132&$-$0.93 \\ 3100.7738 & 32 240.645 & 8320.373 & $-$1.30 \\ 3110.7976 & 32 136.787 & 13665.686 & $-$1.33 \\ 3113.1748 & 32 112.245 & 13690.228 & $-$1.19 \\ 3128.9145 & 31 950.748 & 11339.590 & $-$1.34 \\ 3129.6522 & 31 943.127 & 10653.427 & $-$0.81 \\ 3130.783$^{\star}$ &31 931.636 &3542.561&$+$0.41 \\ 3135.925$^{\star}$ &31 879.275 &7900.644&$-$1.32 \\ 3145.402$^{\star}$ &31 783.232 &8320.373&$+$0.12 \\ 3163.140$^{\star}$ &31 605.006 &6192.310&$-$1.38 \\ 3163.401$^{\star}$ &31 602.404 & 3029.629&$+$0.27 \\ 3175.7747 & 31 479.219 & 10653.427 & $-$0.78 \\ 3175.8669 & 31 478.359 & 17292.479 & $+$0.07 \\ 3177.766$^{\star}$ &31 459.546 &8320.374&$-$1.80 \\ 3179.2265 & 31 445.143 & 13479.460 & $-$1.53 \\ 3180.285$^{\star}$ &31 434.626 &7900.644&$+$0.10 \\ 3181.398$^{\star}$ &31 423.636 &7261.324&$-$1.12 \\ 3188.3466 & 31 355.170 & 12263.221 & $-$1.59 \\ 3189.2788 & 31 345.949 & 17424.889 & $-$0.25 \\ 3191.094$^{\star}$ &31 328.160 &4146.037&$-$0.33 \\ 3193.4495 & 31 305.026 & 13665.686 & $-$1.77 \\ 3194.2782 & 31 296.809 & 10835.837 & $-$0.77 \\ 3194.974$^{\star}$ &31 290.112 &2629.132&$+$0.12 \\ 3206.340$^{\star}$ &31 179.195 &7505.765&$+$0.04 \\ \hline 3207.331$^{\star}$ &31 169.564 &5562.241&$-$1.37 \\ 3215.594$^{\star}$ &31 089.472 &8320.374&$-$0.24 \\ 3216.187$^{\star}$ &31 083.743 &7900.644&$-$1.52 \\ 3222.0580 & 31 027.117 & 12263.221 & $-$0.73 \\ 3223.326$^{\star}$ &31 014.897 &8320.374&$-$0.74 \\ 3225.471$^{\star}$ &30 994.274 & 2356.816&$-$0.01 \\ 3229.557$^{\star}$ &30 955.063 &7261.324&$-$0.75 \\ 3236.400$^{\star}$ &30 889.615 &7900.644&$-$0.30 \\ 3237.9954 & 30 874.306 & 10835.837 & $-$0.72 \\ 3242.4077 & 30 832.382 & 13054.696 & $-$1.47 \\ 3244.5078 & 30 812.426 & 12805.965 & $-$1.26 \\ 3247.470$^{\star}$ &30 784.316 &7900.644&$-$0.74 \\ 3248.932$^{\star}$ &30 770.464 &6192.310&$-$1.11 \\ 3254.062$^{\star}$ &30 721.958 &2629.132&$-$0.50 \\ 3267.673$^{\star}$ &30 594.001 &10604.229&$-$1.38 \\ 3273.505$^{\star}$ &30 539.495 &6192.310&$-$1.55 \\ 3273.880$^{\star}$ &30 535.992 &7261.324&$-$1.68 \\ 3277.7583 & 30 499.863 & 13118.528 & $-$1.66 \\ 3291.051$^{\star}$ &30 376.683 &3542.561&$-$1.54 \\ 3297.045$^{\star}$ &30 321.461 &3029.629&$-$1.63 \\ 3299.5510 & 30 298.404 & 14626.199 & $-$1.16 \\ 3302.616$^{\star}$ &30 270.315 &9509.604&$-$1.49 \\ 3303.3216 & 30 263.848 & 14660.755 & $-$0.93 \\ 3304.7036 & 30 251.221 & 15551.252 & $-$0.78 \\ 3319.585$^{\star}$ &30 115.577 &7261.324&$-$0.91 \\ 3340.3740 & 29 928.163 & 13690.228 & $-$1.59 \\ 3341.596$^{\star}$ &29 917.215 &10186.390&$-$0.46 \\ 3343.892$^{\star}$ &29 896.672 &7900.644&$-$1.31 \\ 3343.966$^{\star}$ &29 896.014 &8320.374&$-$0.89 \\ 3346.751$^{\star}$ &29 871.136 &7505.765&$-$1.23 \\ 3348.7755 & 29 853.103 & 15949.370 & $-$0.90 \\ 3365.587$^{\star}$ &29 703.963 &8320.374&$-$0.74 \\ 3365.872$^{\star}$ &29 701.450 &7261.324&$-$1.54 \\ 3372.5601 & 29 642.544 & 10918.474 & $-$0.80 \\ 3374.246$^{\star}$ &29 627.738 &7900.644&$-$1.19 \\ 3386.238$^{\star}$ &29 522.818 &9812.452&$-$0.46 \\ 3388.929$^{\star}$ &29 499.376 &10604.229&$-$1.31 \\ 3391.587$^{\star}$ &29 476.257 &7900.644&$-$1.85 \\ 3394.9714 & 29 446.922 & 12263.221 & $-$0.80 \\ 3395.7224 & 29 440.466 & 14626.199 & $-$1.28 \\ 3399.7112 & 29 405.910 & 14660.755 & $-$0.63 \\ 3408.673$^{\star}$ &29 328.512 &6192.310&$-$0.58 \\ 3409.185$^{\star}$ &29 324.113 &5562.241&$-$0.87 \\ 3412.932$^{\star}$ &29 291.914 &7261.324&$-$0.50 \\ 3420.625$^{\star}$ &29 226.040 &7505.765&$-$1.12 \\ 3421.1646 & 29 221.428 & 11339.590 & $-$1.36 \\ 3425.420$^{\star}$ &29 185.131 &10918.474&$-$0.26 \\ 3426.528$^{\star}$ &29 175.690 &10604.229&$-$0.78 \\ 3426.568$^{\star}$ &29 175.356 &9509.604&$-$0.50 \\ 3436.821$^{\star}$ &29 088.315 &10246.955&$-$1.30 \\ 3439.918$^{\star}$ &29 062.130 &7900.644&$-$1.04 \\ 3440.581$^{\star}$ &29 056.528 &8320.373&$-$0.69 \\ 3448.2179 & 28 992.192 & 14626.199 & $-$1.06 \\ 3448.6696 & 28 988.438 & 14660.755 & $-$1.09 \\ 3450.7619 & 28 970.875 & 14678.318 & $-$0.90 \\ 3452.3409 & 28 957.636 & 14660.755 & $-$0.70 \\ 3478.786$^{\star}$ &28 737.432 &10246.955&$-$0.84 \\ 3479.560$^{\star}$ &28 731.041 &10604.229&$-$0.46 \\ 3484.046$^{\star}$ &28 694.044 &6192.310&$-$1.06 \\ 3489.087$^{\star}$ &28 652.594 &7900.644&$-$1.08 \\ 3515.416$^{\star}$ &28 438.005 &10246.955&$-$0.59 \\ 3528.4778 & 28 332.703 & 17469.770 & $-$0.66 \\ 3537.622$^{\star}$ &28 259.498 &7261.324&$-$0.96 \\ \hline 3540.959$^{\star}$ &28 232.865 & 8320.373&$-$0.43 \\ 3541.2454 & 28 230.683 & 13479.460 & $-$0.85 \\ 3591.194$^{\star}$ &27 837.946 &10186.390&$-$1.31 \\ 3619.509$^{\star}$ &27 620.178 &7900.644&$-$0.42 \\ 3633.121$^{\star}$ &27 516.698 &12263.221&$-$1.53 \\ 3639.0501 & 27 471.891 & 14660.755 & $-$0.98 \\ 3641.3782 & 27 454.328 & 14678.318 & $-$1.56 \\ 3651.182$^{\star}$ &27 380.589 &7505.765&$-$0.48 \\ 3688.189$^{\star}$ &27 105.862 &10918.474&$-$1.44 \\ 3691.1738 & 27 083.944 & 14626.199 & $-$1.24 \\ 3695.8960 & 27 049.388 & 14660.755 & $-$0.62 \\ 3717.0600 & 26 895.332 & 13665.686 & $+$0.03 \\ 3720.4532 & 26 870.790 & 13690.228 & $-$0.51 \\ 3740.720$^{\star}$ &26 725.223 &13054.696&$-$0.31 \\ 3741.288$^{\star}$ &26 721.166 &12263.221&$-$1.39 \\ 3781.372$^{\star}$ &26 437.919 &13665.686&$-$0.47 \\ 3801.136$^{\star}$ &26 300.459 &13479.460&$-$0.65 \\ 3804.012$^{\star}$ &26 280.574 &13054.696&$-$0.98 \\ 3818.856$^{\star}$ &26 178.422 &12805.965&$-$0.22 \\ 3828.243$^{\star}$ &26 114.233 &13665.686&$-$0.86 \\ 3831.844$^{\star}$ &26 089.691 &13690.228&$-$0.25 \\ 3855.489$^{\star}$ &25 929.691 &13054.696&$-$1.17 \\ 3863.042$^{\star}$ &25 878.995 &12805.965&$-$0.85 \\ 3865.004$^{\star}$ &25 865.859 &13118.528&$-$0.83 \\ 3879.3421 & 25 770.263 & 14790.755 & $-$0.55 \\ 3898.285$^{\star}$ &25 645.042 &13690.228&$-$0.69 \\ 3909.3197 & 25 572.655 & 19351.948 & $-$1.85 \\ 3919.701$^{\star}$ &25 504.927 &13479.460&$-$0.93 \\ 3949.445$^{\star}$ &25 312.850 &14790.755&$-$1.06 \\ 3952.363$^{\star}$ &25 294.159 &13690.228&$-$0.93 \\ 4000.603$^{\star}$ &24 989.164 &14790.755&$-$1.03 \\ 4026.3014 & 24 829.673 & 18819.520 & $-$1.53 \\ 4059.674$^{\star}$ &24 625.566 &13665.686&$-$1.18 \\ 4061.9711 & 24 611.648 & 15949.370 & $-$1.02 \\ 4073.080$^{\star}$ &24 544.515 &14790.755&$-$1.36 \\ 4085.3468 & 24 470.818 & 18819.520 & $-$1.28 \\ 4104.160$^{\star}$ &24 358.650 &13665.686&$-$1.24 \\ 4110.309$^{\star}$ &24 322.205 &13054.696&$-$1.61 \\ 4114.5320 & 24 297.245 & 19351.948 & $-$1.44 \\ 4126.178$^{\star}$ &24 228.667 &15551.252&$-$1.49 \\ 4138.452$^{\star}$ &24 156.809 &12805.965&$-$1.65 \\ 4156.671$^{\star}$ &24 050.933 &16052.672&$-$1.12 \\ 4185.5335 & 23 885.074 & 21039.529 & $-$1.07 \\ 4216.226$^{\star}$ &23 711.215 &13665.686&$-$1.45 \\ 4254.385$^{\star}$ &23 498.542 &13054.696&$-$1.23 \\ 4321.481$^{\star}$ &23 133.708 &15551.252&$-$1.20 \\ 4367.3789 & 22 890.623 & 18819.520 & $-$1.19 \\ 4367.960$^{\star}$ &22 887.552 &13665.686&$-$1.03 \\ 4421.6458 & 22 609.664 & 21039.529 & $-$1.31 \\ 4467.8849 & 22 375.702 & 21511.376 & $-$1.26 \\ 4492.9563 & 22 250.809 & 21039.529 & $-$0.87 \\ 4522.1931 & 22 107.015 & 21511.376 & $-$1.20 \\ 4527.636$^{\star}$ &22 080.389 &12805.965&$-$1.29 \\ 4579.444$^{\star}$ &21 830.594 &13690.228&$-$1.02 \\ 4588.9970 & 21 785.149 & 20347.497 & $-$1.46 \\ 4699.5812 & 21 272.640 & 20437.503 & $-$1.04 \\ \hline%\\[-3mm] %\multicolumn{4}{l}{Note: fot the starred values, see the text.} \end{tabular} \tablefoot{For the starred values, see the text.} \end{table}