Refine Search

New Search

Results: 5

(searched for: doi:10.1088/1009-9271/8/6/03)
Save to Scifeed
Page of 1
Articles per Page
by
Show export options
  Select all
Man I Lam, Hong Wu, , Yi-Nan Zhu, , , , , Yong Zhang, , et al.
Research in Astronomy and Astrophysics, Volume 15, pp 1424-1437; https://doi.org/10.1088/1674-4527/15/8/022

Abstract:
We report the discovery of 64 luminous infrared galaxies, based on new observations of 20 square degrees from the LAMOST Complete Spectroscopic Survey of Pointing Area at the Southern Galactic Cap and the WISE 22 μm catalog from the AllWISE Data Release. Half of them are classified as late-type spirals and the others are classified as peculiar/compact galaxies. The peculiar/compact galaxies tend to exhibit higher luminosities and lower stellar masses. We also separate AGNs from HII galaxies in a simple way by examining LAMOST spectra. Those cases show that host AGNs are easily distinguished from others in the mid-infrared color-color diagrams.
Published: 25 November 2014
The Astronomical Journal, Volume 149; https://doi.org/10.1088/0004-6256/149/1/1

Abstract:
Stellar bars are important internal drivers of secular evolution in disk galaxies. Using a sample of nearby spiral galaxies with weak and strong bars, we explore the relationships between the star formation feature and stellar bars in galaxies. We find that galaxies with weak bars tend coincide with low concentrical star formation activity, while those with strong bars show a large scatter in the distribution of star formation activity. We find enhanced star formation activity in bulges toward stronger bars, although not predominantly, consistent with previous studies. Our results suggest that different stages of the secular process and many other factors may contribute to the complexity of the secular evolution. In addition, barred galaxies with intense star formation in bars tend to have active star formation in their bulges and disks, and bulges have higher star formation densities than bars and disks, indicating the evolutionary effects of bars. We then derived a possible criterion to quantify the different stages of the bar-driven physical process, while future work is needed because of the uncertainties.
Xian-Min Meng, Hong Wu,
Research in Astronomy and Astrophysics, Volume 11, pp 419-433; https://doi.org/10.1088/1674-4527/11/4/005

Abstract:
We present a stellar population synthesis study of a type II luminous infrared galaxy, IRASF21013-0739. Optical images show clear characteristics of a merger remnant. The H-band absolute magnitude is MH = −25.1, which is ~2 times as luminous as L* galaxies. Stellar populations are obtained through the stellar synthesis code STARLIGHT. We find that it experienced a recent starburst (SB) phase ~ 100 Myr ago. By reconstructing the ultraviolet-to-optical spectrum, and adopting Calzetti et al. and Leitherer et al.'s extinction curves, we estimate the past infrared (IR) luminosities of the host galaxy and find it may have experienced an ultraluminous infrared galaxy phase which lasted for about 100 Myr. Its i-band absolute magnitude is Mi = −22.463, and its spectral type shows type 2 active galactic nucleus (AGN) characteristics. The mass of the supermassive black-hole is estimated to be MBH = 1.6 × 107M (lower-limit). The Eddington ratio Lbol/LEdd is 0.15, which is typical of Palomar-Green (PG) quasars. Both the nuclear SB and AGN contribute to the present IR luminosity budget, and the SB contributes ~67%. On the diagram of IR color versus IR/optical excess, it is located between IR quasars and PG quasars. These results indicate that IRASF21013-0739 has probably evolved from a ULIRG, and it can possibly evolve into an AGN.
Xian-Min Meng, Hong Wu, Qiu-Sheng Gu, Jing Wang, Chen Cao
Published: 8 July 2010
The Astrophysical Journal, Volume 718, pp 928-938; https://doi.org/10.1088/0004-637x/718/2/928

Abstract:
We present a stellar population synthesis study of a type I luminous infrared galaxy: IRAS F13308+5946. It is a quasar with absolute magnitude Mi = –22.56 and has the spectral feature of a Seyfert 1.5 galaxy. Optical images show characteristics of later stages of a merger. With the help of the stellar synthesis code STARLIGHT and both Calzetti et al.'s and Leitherer et al.'s extinction curves, we estimate the past infrared (IR) luminosities of the host galaxy and find that it may have experienced an ultraluminous infrared galaxy (ULIRG) phase for nearly 300 Myr, so this galaxy has probably experienced a type I ULIRG phase. Both nuclear starburst (SB) and active galactic nuclei contribute to the present IR luminosity budget, with the SB contributing ~70%. The mass of the supermassive black hole is MBH = 1.8 × 108M and the Eddington ratio Lbol/LEdd is 0.12, both of which are approximate typical values of Palomar-Green QSOs. These results indicate that IRAS F13308+5946 is probably at the transitional phase from a type I ULIRG to a classical QSO.
X. Y. Chen, Y. C. Liang, F. Hammer, Y. H. Zhao, G. H. Zhong
Published: 14 January 2009
Astronomy & Astrophysics, Volume 495, pp 457-469; https://doi.org/10.1051/0004-6361:200810629

Abstract:
Astronomy & Astrophysics (A&A) is an international journal which publishes papers on all aspects of astronomy and astrophysics
Page of 1
Articles per Page
by
Show export options
  Select all
Back to Top Top