The Leo Triplet: Common origin or late encounter?

被引:18
作者
Afanasiev, VL [1 ]
Sil'chenko, OK
机构
[1] Special Astrophys Observ, Nizhnii Arkhyz 369167, Russia
[2] Moscow MV Lomonosov State Univ, Sternberg Astron Inst, Moscow 119992, Russia
[3] Isaac Newton Inst Chile, Moscow Branch, Moscow, Russia
来源
ASTRONOMY & ASTROPHYSICS | 2005年 / 429卷 / 03期
关键词
galaxies : individual : NGC 3623; galaxies : individual : NGC 3627; galaxies : nuclei; galaxies : stellar content; galaxies : kinematics and dynamics; galaxies : evolution;
D O I
10.1051/0004-6361:20040311
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The kinematics, structure, and stellar population properties in the centers of two early-type spiral galaxies of the Leo Triplet, NGC 3627 and NGC 3623, are studied by means of integral-field spectroscopy. Unlike our previous targets, NGC 3384/NGC 3368 in the Leo I Group and NGC 5574/NGC 5576 in LGG 379, NGC 3623 and NGC 3627 do not appear to experience a synchronous evolution. The mean ages of their circumnuclear stellar populations are quite different, and the magnesium overabundance of the nucleus in NGC 3627 is evidence for a very brief last star formation event 1 Gyr ago whereas the evolution of the central part of NGC 3623 looks more quiescent. In the center of NGC 3627 we observe noticeable gas radial motions, and the stars and the ionized gas in the center of NGC 3623 demonstrate more or less stable rotation. However, NGC 3623 has a chemically distinct core-a relic of a past star formation burst-which is shaped as a compact, dynamically cold stellar disk with a radius of similar to250-350 pc which has been formed not later than 5 Gyr ago.
引用
收藏
页码:825 / 836
页数:12
相关论文
共 35 条
[1]   The SAURON project - I. The panoramic integral-field spectrograph [J].
Bacon, R ;
Copin, Y ;
Monnet, G ;
Miller, BW ;
Allington-Smith, JR ;
Bureau, M ;
Carollo, CM ;
Davies, RL ;
Emsellem, E ;
Kuntschner, H ;
Peletier, RF ;
Verolme, EK ;
de Zeeuw, PT .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2001, 326 (01) :23-35
[2]   Bulge-disk decomposition of 659 spiral and lenticular galaxy brightness profiles [J].
Baggett, WE ;
Baggett, SM ;
Anderson, KSJ .
ASTRONOMICAL JOURNAL, 1998, 116 (04) :1626-1642
[3]   A study of the direct fitting method for measurement of galaxy velocity dispersions [J].
Barth, AJ ;
Ho, LC ;
Sargent, WLW .
ASTRONOMICAL JOURNAL, 2002, 124 (05) :2607-2614
[4]  
BEGEMAN KG, 1989, ASTRON ASTROPHYS, V223, P47
[5]  
BURKHEAD MS, 1981, ASTRON J, V86, P523, DOI 10.1086/112910
[6]   The SAURON project - II. Sample and early results [J].
de Zeeuw, PT ;
Bureau, M ;
Emsellem, E ;
Bacon, R ;
Carollo, CM ;
Copin, Y ;
Davies, RL ;
Kuntschner, H ;
Miller, BW ;
Monnet, G ;
Peletier, RF ;
Verolme, EK .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2002, 329 (03) :513-530
[7]   The SAURON project - III. Integral-field absorption-line kinematics of 48 elliptical and lenticular galaxies [J].
Emsellem, E ;
Cappellari, M ;
Peletier, RF ;
McDermid, RM ;
Bacon, R ;
Bureau, M ;
Copin, Y ;
Davies, RL ;
Krajnovic, D ;
Kuntschner, H ;
Miller, BW ;
de Zeeuw, PT .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2004, 352 (03) :721-743
[8]   Line strengths and line strength gradients in S0 galaxies [J].
Fisher, D ;
Franx, M ;
Illingworth, G .
ASTROPHYSICAL JOURNAL, 1996, 459 (01) :110-+
[9]   NEUTRAL HYDROGEN STREAMS IN GROUPS OF GALAXIES .1. OBSERVATIONS [J].
HAYNES, MP .
ASTRONOMICAL JOURNAL, 1981, 86 (08) :1126-1154
[10]   DETAILED EXAMINATION OF THE NEUTRAL HYDROGEN DISTRIBUTION IN THE LEO TRIPLET NGC 3623, 3627, AND 3628 [J].
HAYNES, MP ;
GIOVANELLI, R ;
ROBERTS, MS .
ASTROPHYSICAL JOURNAL, 1979, 229 (01) :83-&