Zobrazeno 1 - 10
of 94
pro vyhledávání: '"Walter Dehnen"'
Publikováno v:
The Astrophysical Journal, Vol 974, Iss 2, p 204 (2024)
Scouring by supermassive black hole (SMBH) binaries is the most accepted mechanism for the formation of the cores seen in giant elliptical galaxies. However, an additional mechanism is required to explain the largest observed cores. Gravitational-wav
Externí odkaz:
https://doaj.org/article/1f965b1e0d9544cd9260486d2749b591
Publikováno v:
Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society, 2023, 519, pp.902-908. ⟨10.1093/mnras/stac3528⟩
Monthly Notices of the Royal Astronomical Society, 2023, 519, pp.902-908. ⟨10.1093/mnras/stac3528⟩
The angular-momentum distribution of classical Cepheids in the outer Milky Way disc is bi-modal with a gap at $L_\mathrm{gap}=2950\,\mathrm{km}\,\mathrm{s}^{-1}\,\mathrm{kpc}$, corresponding to $R=13\,\mathrm{kpc}$, while no similar feature has been
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::47aec5ef861b0965dcbaef2ccd15a3e5
https://doi.org/10.1093/mnras/stac3528
https://doi.org/10.1093/mnras/stac3528
Autor:
Hossam Aly, Walter Dehnen
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 518:2651-2660
We present a family of analytical potential-density pairs for barred discs, which can be combined to describe galactic bars in a realistic way, including boxy/peanut components. We illustrate this with two reasonable compound models. Computer code fo
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b1b14a7407ec789fb00e7804e1586c82
https://doi.org/10.1093/mnras/stac3124
https://doi.org/10.1093/mnras/stac3124
Publikováno v:
Monthly Notices of the Royal Astronomical Society.
We examine the Galactic warp in a sample of all classical Cepheids with Gaia DR3 radial velocity. In each radial bin, we determine (1) the inclined plane normal to the mean orbital angular momentum of the stars and (2) that best fitting their positio
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b34904626d23afe609a57df0a5061357
https://doi.org/10.1093/mnras/stad1502
https://doi.org/10.1093/mnras/stad1502
Autor:
Walter Dehnen, David Michael Hernandez
We present a simple algorithm to switch between $N$-body time integrators in a reversible way. We apply it to planetary systems undergoing arbitrarily close encounters and highly eccentric orbits, but the potential applications are broader. Upgrading
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::acf9cd98c36e36fb9ea53b982353e6b6
We describe methods to measure simultaneously the orientation angle $\psi$ and pattern speed $\Omega$ from single snapshots of simulated barred galaxies. Unlike previous attempts, our approach is unbiased, precise, and consistent in the sense that $\
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9026eae77284aa49b75142aec91123ff
http://arxiv.org/abs/2211.00674
http://arxiv.org/abs/2211.00674
Publikováno v:
Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society, 2022, 517, pp.6060-6063. ⟨10.1093/mnras/stac3085⟩
Monthly Notices of the Royal Astronomical Society, 2022, 517, pp.6060-6063. ⟨10.1093/mnras/stac3085⟩
We analyse the distribution of Mira variable stars in the central region of the Milky Way. We find that with increasing period, i.e. decreasing age, the Miras shift towards negative Galactic longitudes $\ell$. Comparing to a cosmological zoom simulat
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0743a5dfff3159839b18b181f0a0e10b
Capture of interstellar objects (ISOs) into the Solar system is dominated by ISOs with asymptotic incoming speeds $v_\infty
8 pages, to be published by MNRAS
8 pages, to be published by MNRAS
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2c2f347e7e878c5525f5bd12933a3b1e
http://arxiv.org/abs/2112.07486
http://arxiv.org/abs/2112.07486
In galactic nuclei, the gravitational potential is dominated by the central supermassive black hole, so stars follow quasi-Keplerian orbits. These orbits are distorted by gravitational forces from other stars, leading to long-term orbital relaxation.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5e14ed161df337fa88d7d58399e8ae06
https://hal.archives-ouvertes.fr/hal-03372775
https://hal.archives-ouvertes.fr/hal-03372775
Publikováno v:
Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society, 2022, 509, pp.4532-4537. ⟨10.1093/mnras/stab3294⟩
Monthly Notices of the Royal Astronomical Society, 2022, 509, pp.4532-4537. ⟨10.1093/mnras/stab3294⟩
We analyse the positions of RR Lyrae stars in the central region of the Milky Way. In addition to the overall bar shape detected previously, we find evidence for a peanut shaped structure, in form of overdensities near $\ell=-2$ deg and $1$ deg at $b
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2824c6a6dca40488957012038753b788
http://arxiv.org/abs/2107.10907
http://arxiv.org/abs/2107.10907