Supernovae in Doppelsternen, Schnellläufersterne, Neutronensternkicks und kinematische Alter
Zusammenfassung der Projektergebnisse
Our search in the Gaia DR2 catalogue for runaway stars in twelve Galactic SNRs yielded no further certain runaway stars besides HD 37424, but 73 new promising candidates. Among these, five stars in the Monoceros Loop and one in Vela Jr. were observed with UVESNLT and four stars in HB9 with Subaru/HDS. ln total, we observed 39 stars, where 29 were ruled out, e.g. after revisiting their motion with Gaia DR2 data or they turned out to be giants. We found six dwarf stars with lithium; two in Monoceros, two in Vela and two in Vela Jr. TYC159-343-1, located in the Monoceros Loop in projection, might be a young star. We obtained 90-625 Myr from the HRD, but its Li signal is hard to interpret due to the early spectral type (F3) and its low metallicity. Even 2.1-3.8 Myr, the pre-MS solution is possible. However, using DR2 data and an updated distance ofthe Monoceros Loop, TYC159-343-1 had to be ruled out because it is too close. The same applies to TYC159-251-1, which was discovered by us to be a double-lined spectroscopic binary. TYC8150-3105-1 in Vela shows the strongest Li absorption among all observed stars, so it was tound to be younger than ca. 50 Myr. The Li-rich stars in Vela (TYC8150-3105-1 and TYC8150-2802-1) were ruled out because they are not consistent with the motion of the PSR. They could be interlopers near the volume of the SNR while TYC8150-3105-1 could also be a member of the same OB association trom which the SNR formed. The Li-rich stars in Vela Jr. were ruled out because they are too old, which can be seen from their relatively small Li abundances. The B-type star HD 261393 is the most likely candidate in the Monoceros Loop. ln Vela, we point out two stars which are consistent with the motion of the Vela PSR. ln total, we found 74 good runaway star candidates with G < 17 mag, mostly with spectral type K. Among the twelve investigated SNRs, nine SNe could have ejected a runaway star, while only HD 37424 in S147 is confirmed. Three of these SNe could possibly have ejected two runaway stars. Note that we might miss some stars with G > 17 mag which would mainly be spectral type M. Due to missing observations of such late-type stars around high-mass primaries, we do not know how many M-type runaway stars we could expect. Furthermore, we might miss some Gaia DR2 candidates due to our strict selection limit from the allowed angular distance to the geometric centre of the SNR at the time of the SN, which was necessary to create feasible observing projects. ln order to finally proot a binary supernova ejection origin, we need to observe the best candidates with very high resolution and S/N to be able to detect SN ciebris, e.g. heavy- and α-elements, in the stellar atmospheres. We also emphasise that it is important to precisely know the explosion site. The case of HD 37424 in SNR S147 is rather exceptional, because both the pulsar and the runaway star trace back to the Green centre and meet it within just a few arcminutes. We did not find other cases where a pair of a pulsar and a runaway star candidate was located so close to the geometric center of the SNR. ln general, the explosion site will not coincide with the geometric center of the SNR, due to the motion of the local standard of rest and due to asymmetries of the SNR expansion. A careful analysis of the time-dependent SNR morphology is needed to locate the explosion site.
Projektbezogene Publikationen (Auswahl)
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The radial and rotational velocity of ζ Ophiuchi. Astronomische Nachrichten, 339(1), 46-52.
Zehe, T.; Mugrauer, M.; Neuhäuser, R.; Pannicke, A.; Lux, O.; Bischoff, R.; Wöckel, D. & Wagner, D.
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A nearby recent supernova that ejected the runaway star ζ Oph, the pulsar PSR B1706−16, and 60Fe found on Earth. Monthly Notices of the Royal Astronomical Society, 498(1), 899-917.
Neuhäuser, R.; Gießler, F. & Hambaryan, V. V.
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Identification of young nearby runaway stars based on Gaia data and the lithium test†. Astronomische Nachrichten, 341(9), 908-942.
Bischoff, Richard; Mugrauer, Markus; Torres, Guillermo; Heyne, Theresa; Lux, Oliver; Munz, Vera; Neuhäuser, Ralph; Hoffmann, Susanne & Trepanovski, Anja
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Radial velocity measurements of the runaway stars AE Aur and ι Ori. Astronomische Nachrichten, 341(6-7), 645-650.
Heyne, Therese; Mugrauer, M.; Bischoff, R.; Wagner, D.; Neuhäuser, R.; Hoffmann, S. M. & Lux, O.
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A search for runaway stars in 12 Galactic supernova remnants. Astronomische Nachrichten, 342(3), 553-577.
Lux, Oliver; Neuhäuser, Ralph; Mugrauer, Markus & Bischoff, Richard
