Results 11 to 20 of about 20,011 (211)

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

Astronomische 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, J. Heidt, A. Pramskiy, D. Thompson, G. Agapito, S. Esposito, R. Gredel, D. Miller, E. Pinna, A. Puglisi, F. Rossi, W. Seifert, G. Taylor, A. Quirrenbach   +13 more
wiley   +1 more source

Multiwavelength astrophysics of the blazar OJ 287 and the project MOMO

Astronomische 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, A. Kraus, D. Grupe, M.L. Parker, A. Gonzalez, L.C. Gallo, M.A. Gurwell, S. Laine, S. Yao, S. Chandra, L. Dey, J.L. Gómez, K. Hada, D. Haggard, A.R. Hollett, H. Jermak, S. Jorstad, T.P. Krichbaum, S. Markoff, C. McCall, J. Neilsen, M. Nowak   +21 more
wiley   +1 more source

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

Astronomische 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

Astronomische 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

Journal 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

X-ray absorption, interstellar reddening, and elemental abundances in the interstellar medium

Astrophysical Journal, 1975
C J Cesarsky, J Audouze
exaly   +2 more sources

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

, 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., Cox, Nick L. J., Evans, Christopher J., Gordon, Karl D., Sarre, Peter J., Smith, Keith T., Trundle, Carrie   +6 more
core   +1 more source

A representative sample of Be stars IV: Infrared Photometry and the Continuum Excess [PDF]

, 2001
We present infra-red (JHK) photometry of 52 isolated Be stars of spectral types O9--B9 and luminosity classes III--V. We describe a new method of reduction, enabling separation of interstellar reddening and circumstellar excess.
Alonso, Bjorkman, Clark, Cramer, Dachs, Dachs, Dougherty, Dougherty, Elias, Gehrz, Hanson, Hanson, Hanuschik, Hirata, Hummel, I. A. Steele, J. Etherton, John M. Porter, Koornneef, Lamers, Lee, Lee Howells, Leggett, Okazaki, Osaki, Owocki, Poeckert, Porter, Porter, Quirrenbach, Rieke, Slettebak, Slettebak, Steele, van Kerkwijk, Wall, Wall, Waters, Waters   +38 more
core   +2 more sources

The Distribution of Interstellar Reddening Material

Astronomical Journal, 1968
exaly   +2 more sources

One Relation for All Wavelengths: The Far-ultraviolet to Mid-infrared Milky Way Spectroscopic R(V)-dependent Dust Extinction Relationship

The Astrophysical Journal, 2023
Dust extinction is one of the fundamental measurements of dust grain sizes, compositions, and shapes. Most of the wavelength-dependent variations seen in Milky Way extinction are strongly correlated with the single parameter R ( V ) = A ( V )/ E ( B − V )
Karl D. Gordon, Geoffrey C. Clayton, Marjorie Decleir, E. L. Fitzpatrick, Derck Massa, Karl A. Misselt, Erik J. Tollerud   +6 more
doaj   +1 more source