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Table 1.

Runaway stars according to the traced-back flight paths.

Star SigMA No. of Group age Nenc s ¯ min Mathematical equation: $ \overline{s}_{\text{min}} $ t ( s ¯ min ) Mathematical equation: $ t(\overline{s}_{\text{min}}) $ vpec,3D Penc/Prnd Scenario
stars [Myr] [per 1000] [pc] [Myr] [km/s]
λ CMa 21 1805 15 . 5 0.5 + 0.6 Mathematical equation: $ 15.5_{-0.5}^{+0.6} $ 243 4.77 4.60 ± 1.35 28.03 119.17 BSS
λ CMa 17 516 20 . 9 0.8 + 0.7 Mathematical equation: $ 20.9_{-0.8}^{+0.7} $ 188 2.41 5.41 ± 1.24 32.17 93.54 BSS
λ CMa 15 1114 16 . 9 0.6 + 0.9 Mathematical equation: $ 16.9_{-0.6}^{+0.9} $ 163 4.09 5.61 ± 1.22 30.85 97.57 BSS

HD 160093 10 1029 15 . 0 1.4 + 0.9 Mathematical equation: $ 15.0_{-1.4}^{+0.9} $ 172 2.74 6.68 ± 0.79 43.64 747.54 BSS

66 Eri 8 373 14 . 7 0.7 + 0.8 Mathematical equation: $ 14.7_{-0.7}^{+0.8} $ 211 1.78 8.20 ± 1.65 22.82 136.12 BSS
66 Eri 17 516 20 . 9 0.8 + 0.7 Mathematical equation: $ 20.9_{-0.8}^{+0.7} $ 172 1.23 7.48 ± 2.14 24.09 86.14 BSS
66 Eri 14 769 15 . 3 0.3 + 0.6 Mathematical equation: $ 15.3_{-0.3}^{+0.6} $ 166 1.63 7.35 ± 1.52 23.03 162.36 BSS

γ Gru 8 373 14 . 7 0.7 + 0.8 Mathematical equation: $ 14.7_{-0.7}^{+0.8} $ 266 4.27 2.38 ± 0.48 29.58 80.78 BSS
γ Gru 13 226 6 . 0 0.9 + 0.6 Mathematical equation: $ 6.0_{-0.9}^{+0.6} $ 233 0.72 5.79 ± 0.58 29.93 346.36 DES
γ Gru 14 769 15 . 3 0.3 + 0.6 Mathematical equation: $ 15.3_{-0.3}^{+0.6} $ 186 3.81 4.52 ± 0.57 32.54 59.18 BSS

γ Crv 15 1114 16 . 9 0.6 + 0.9 Mathematical equation: $ 16.9_{-0.6}^{+0.9} $ 515 2.75 2.60 ± 0.74 31.16 78.48 BSS
γ Crv 13 226 6 . 0 0.9 + 0.6 Mathematical equation: $ 6.0_{-0.9}^{+0.6} $ 305 0.29 3.98 ± 0.45 32.02 281.48 DES
γ Crv 14 769 15 . 3 0.3 + 0.6 Mathematical equation: $ 15.3_{-0.3}^{+0.6} $ 201 6.41 3.25 ± 0.65 32.00 66.70 BSS
γ Crv 17 516 20 . 9 0.8 + 0.7 Mathematical equation: $ 20.9_{-0.8}^{+0.7} $ 172 4.94 4.03 ± 0.88 32.76 20.94 BSS

α2 CVn 8 373 14 . 7 0.7 + 0.8 Mathematical equation: $ 14.7_{-0.7}^{+0.8} $ 153 4.58 4.95 ± 0.73 31.08 38.10 BSS

β Lib 9 276 19 . 1 1.3 + 2.4 Mathematical equation: $ 19.1_{-1.3}^{+2.4} $ 201 4.11 2.38 ± 0.48 34.19 24.96 BSS

ζ Oph 9 276 19 . 1 1.3 + 2.4 Mathematical equation: $ 19.1_{-1.3}^{+2.4} $ 393 1.35 0.86 ± 0.10 52.31 4.68 BSS
ζ Oph 21 1805 15 . 5 0.5 + 0.6 Mathematical equation: $ 15.5_{-0.5}^{+0.6} $ 307 3.29 2.72 ± 0.24 55.23 11.53 BSS
ζ Oph 15 1114 16 . 9 0.6 + 0.9 Mathematical equation: $ 16.9_{-0.6}^{+0.9} $ 271 2.09 1.60 ± 0.14 52.99 5.20 BSS
ζ Oph 19 246 14 . 4 0.9 + 0.4 Mathematical equation: $ 14.4_{-0.9}^{+0.4} $ 190 0.79 2.38 ± 0.16 54.29 15.34 BSS
ζ Oph 20 1737 15 . 7 0.9 + 0.3 Mathematical equation: $ 15.7_{-0.9}^{+0.3} $ 162 6.61 2.21 ± 0.17 53.67 5.64 BSS

Notes. The number of calculated close encounters (Nenc) per 1000 simulated orbits is indicated for each star-subgroup pair, along with the mean minimum separation ( s ¯ min Mathematical equation: $ \overline{s}_{\text{min}} $), how far in the past the encounter occurred ( t ( s ¯ min ) Mathematical equation: $ t(\overline{s}_{\text{min}}) $), the peculiar velocity of the candidates with respect to the corresponding subgroups (vpec,3D) as well as the ratio between the number of true close encounters and the number of random pairings (Penc/Prnd). For each star-subgroup pair, a flag indicates which ejection scenario is the likeliest based on the difference between the subgroup’s age and the time that has passed since the ejection; if the difference is below 3 Myr, it likely was ejected dynamically (DES) and if the difference is 3–4 Myr, it was ejected by either DES or BSS. Otherwise, the ejection was likely caused by the binary supernova scenario (BSS). Note that initially, in order to identify the most promising runaway candidates (i.e., those listed here), 1000 traceback simulations were run per star-subgroup pair. For this selection of candidates, the traceback simulations were repeated, but this time with 300 000 runs for each star-subgroup pair; the column Nenc now lists the number of calculated encounters from these repeated traceback runs scaled down to 1000 simulations in order to maintain comparability with Fig. 1 and our reasoning described in Sect. 2.4. Additionally, for each star, the literature was checked in order to determine whether it was previously known as a runaway star, where Tetzlaff et al. (2011, abbreviated as T11), Hoogerwerf et al. (2001, H01), Mdzinarishvili (2004, which did not include any of the stars presented here), Mdzinarishvili & Chargeishvili (2005, which also did not include any of these stars), Carretero-Castrillo et al. (2023, which did not include the stars presented here, either), and Maíz Apellániz et al. (2018, MA18) were used as references. We note that γ Gru (T11), γ Crv (T11), and ζ Oph (T11, H01, MA18) are indeed known runaway stars or candidates.

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