|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'504'928
Articles rated: 2609
26 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
Nuclear Properties of Nearby Spiral Galaxies from Hubble Space Telescope NICMOS imaging and STIS Spectroscopy | | M. A. Hughes
; D. Axon
; J. Atkinson
; A. Alonso-Herrero
; C. Scarlata
; A. Marconi
; D. Batcheldor
; J. Binney
; A. Capetti
; C. M. Carollo
; L. Dressel
; J. Gerssen
; D. Macchetto
; W. Maciejewski
; M. Merrifield
; M. Ruiz
; W. Sparks
; M. Stiavelli
; Z. Tsvetanov
; | | Date: |
31 Mar 2005 | | Subject: | astro-ph | | Abstract: | We investigate the central regions of 23 spiral galaxies using archival NICMOS imaging and STIS spectroscopy. The sample is taken from our program to determine the masses of central massive black holes (MBH) in 54 nearby spiral galaxies. Stars are likely to contribute significantly to any dynamical central mass concentration that we find in our MBH program and this paper is part of a series to investigate the nuclear properties of these galaxies. We use the Nuker law to fit surface brightness profiles, derived from the NICMOS images, to look for nuclear star clusters and find possible extended sources in 3 of the 23 galaxies studied (13 per cent). The fact that this fraction is lower than that inferred from optical Hubble Space Telescope studies is probably due to the greater spatial resolution of those studies. Using R-H and J-H colors and equivalent widths of H-alpha emission (from the STIS spectra) we investigate the nature of the stellar population with evolutionary models. Under the assumption of hot stars ionizing the gas, as opposed to a weak AGN, we find that there are young stellar populations (~10-20 Myr) however these data do not allow us to determine what percentage of the total nuclear stellar population they form. Also, in an attempt to find any unknown AGN we use [N II] and [S II] line flux ratios (relative to H-alpha) and find tentative evidence for weak AGN in NGC 1300 and NGC 4536. | | Source: | arXiv, astro-ph/0503693 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER