Results 11 to 20 of about 19,928 (198)

Decomposition of the central structure of NGC 2273 in the NIR: A case study

open access: yesAstronomische Nachrichten, Volume 344, Issue 10, December 2023., 2023
Abstract The Seyfert 2 galaxy NGC 2273 is a prime target to explore how active nuclei can be fed. It has a star‐forming innermost nuclear ring with a radius of 0.33kpc from where material may be funneled to the supermassive black hole in its center. In this article, we discuss high‐resolution adaptive optics aided JHKs images of NGC 2273 taken with the
L. Schey   +13 more
wiley   +1 more source

Multiwavelength astrophysics of the blazar OJ 287 and the project MOMO

open access: yesAstronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023
Abstract We are carrying out the densest and longest multiyear, multiwavelength monitoring project of OJ 287 ever done. The project MOMO (Multiwavelength Observations and Modeling of OJ 287) covers wavelengths from the radio to the high‐energy regime. A few selected observations are simultaneous with those of the Event Horizon Telescope (EHT).
S. Komossa   +21 more
wiley   +1 more source

Chemical abundances in the dwarf galaxy NGC 4163 based on the nebular and auroral emission lines

open access: yesAstronomische Nachrichten, Volume 343, Issue 9-10, November-December 2022., 2022
Abstract We constructed an oxygen abundance map and N/O ratio map of the unusually low excitation dwarf irregular galaxy NGC 4163 based on publicly available spectroscopy obtained by the MaNGA survey. We detected auroral emission line [O II]λλ$$ \lambda \lambda $$7320,7330 which allows us to measure chemical abundance by direct Te$$ {\mathrm{T}}_e ...
I. A. Zinchenko, L. S. Pilyugin
wiley   +1 more source

An investigation of open cluster Melotte 72 using Gaia DR2

open access: yesAstronomische Nachrichten, Volume 342, Issue 4, Page 613-624, May 2021., 2021
Abstract The estimation of the main parameters of star clusters is significant in astrophysical studies. The most important aspect of using the Gaia DR2 survey lies in the positions, parallax, and proper motions of cluster stars with homogeneous photometry that make the membership probability determine with high accuracy.
Yasser Hendy, Ashraf Tadross
wiley   +1 more source

1I/‘Oumuamua as an N2 Ice Fragment of an exo‐Pluto Surface: I. Size and Compositional Constraints

open access: yesJournal of Geophysical Research: Planets, Volume 126, Issue 5, May 2021., 2021
Abstract The origin of the interstellar object 1I/‘Oumuamua has defied explanation. We perform calculations of the non‐gravitational acceleration that would be experienced by bodies composed of a range of different ices and demonstrate that a body composed of N2 ice would satisfy the available constraints on the non‐gravitational acceleration, size ...
Alan P. Jackson, Steven J. Desch
wiley   +1 more source

A new, large-scale map of interstellar reddening derived from HI emission [PDF]

open access: yes, 2017
We present a new map of interstellar reddening, covering the 39\% of the sky with low {\rm HI} column densities ($N_{\rm HI} < 4\times10^{20}\,\rm cm^{-2}$ or $E(B-V)\approx 45\rm\, mmag$) at $16\overset{'}{.}1$ resolution, based on all-sky observations ...
Doré, Olivier   +2 more
core   +3 more sources

A survey of diffuse interstellar bands in the Andromeda galaxy: optical spectroscopy of M31 OB stars [PDF]

open access: yes, 2010
We present the largest sample to-date of intermediate-resolution blue-to-red optical spectra of B-type supergiants in M31 and undertake the first survey of diffuse interstellar bands (DIBs) in this galaxy.
Cordiner, Martin A.   +6 more
core   +1 more source

Detection of diffuse interstellar bands in M31 [PDF]

open access: yes, 2008
We investigate the diffuse interstellar band (DIB) spectrum in the interstellar medium of M31. The DEIMOS spectrograph of the W. M. Keck observatory was used to make optical spectroscopic observations of two supergiant stars, MAG 63885 and MAG 70817, in ...
Bianchi   +49 more
core   +1 more source

Dust accretion and destruction in galaxy groups and clusters [PDF]

open access: yes, 2010
We examine the dust distribution around a sample of 70,000 low redshift galaxy groups and clusters derived from the Sloan Digital Sky Survey. By correlating spectroscopically identified background quasars with the galaxy groups we obtain the relative ...
Adelman-McCarthy   +65 more
core   +3 more sources

Analysis of Interstellar Extinction towards the Hypergiant Cyg OB2 No. 12

open access: yesOpen Astronomy, 2016
The Cyg OB2 stellar association hosts an entire zoo of unique objects, and among them – an enigmatic star Cyg OB2 No. 12 (Schulte 12, MT 304). MT 304 is enigmatic not only due to its highest luminosity (according to various estimates, it is one of the ...
Maryeva O. V.   +3 more
doaj   +1 more source

Home - About - Disclaimer - Privacy