2004A&A...424..107K


C.D.S. - SIMBAD4 rel 1.7 - 2019.12.13CET08:45:59

2004A&A...424..107K - Astronomy and Astrophysics, volume 424, 107-118 (2004/9-2)

The optical-near-infrared colour of the host galaxies of BL Lacertae objects.

KOTILAINEN J.K. and FALOMO R.

Abstract (from CDS):

We present H-band (1.65µm) imaging of 23 low redshift (z≤0.3) BL Lac objects that were previously investigated by us in the optical R-band. For all the observed objects, the host galaxy is clearly detected and well represented by an elliptical model, with average scale length R(e)=7.2±3.6kpc and average absolute magnitude M(H)=-25.9±0.6. BL Lac hosts are therefore luminous (massive) elliptical galaxies indistinguishable from those of low redshift radio galaxies and inactive ellipticals. The best-fit H-band Kormendy relation of µe=3.7 log re(kpc)+14.8mag/arcsec2 is in agreement with that obtained for normal ellipticals and radio galaxies. This structural and dynamical similarity indicates that all massive elliptical galaxies can experience nuclear activity without significant perturbation of their global structure. The new observations are combined with literature data (Kotilainen et al., 1998A&A...336..479K; Scarpa et al., 2000ApJ...544..258S; Cheung et al., 2003ApJ...599..155C) of 18 objects in order to construct a sizeable dataset of 41 BL Lacs with determined host characteristics in both optical and NIR. This extended sample is used to investigate the optical-NIR colour and colour gradient properties of the host galaxies of BL Lacs and to perform a direct comparison with other elliptical galaxies with and without nuclear activity. The integrated optical/near-infrared colour (R-H=2.2±0.4) and colour gradient (Δ(R-H)/Δ(logr)=-0.38±0.60) distributions of the BL Lac hosts are much wider than those for normal ellipticals with old stellar populations, and many BL Lacs have bluer hosts and/or steeper colour gradients than those in normal ellipticals. The blue colours are most likely caused by a young stellar population, and indicates a link between star formation caused by an interaction/merging event and the onset of the nuclear activity. However, the lack of obvious signs of interaction may require a significant time delay between the event with associated SF episodes and the start of the nuclear activity.

Abstract Copyright:

Journal keyword(s): galaxies: BL Lacertae objects: general - galaxies: active - galaxies: elliptical and lenticular, cD - galaxies: nuclei - galaxies: photometry - infrared: galaxies

Simbad objects: 23

goto Full paper

goto View the reference in ADS

Number of rows : 23

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 2E 369 BLL 01 23 08.648 +34 20 48.56     15.2 16.8   ~ 87 0
2 QSO B0158+001 BLL 02 01 06.1792513040 +00 34 00.135376381   18.99 18.42 18   ~ 90 0
3 QSO B0205+350 BLL 02 08 38.1632218391 +35 23 12.802507619     19.24 18.8   ~ 88 0
4 QSO B0317+18 BLL 03 19 51.8081953152 +18 45 34.570122144     18.12     ~ 183 0
5 6C 113337+702604 BLL 11 36 26.4093954222 +70 09 27.311486691   15.16 14.49 10.51   ~ 308 1
6 QSO B1218+304 BLL 12 21 21.9427463316 +30 10 37.161573795   16.50 15.85 15.7   ~ 378 1
7 QSO B1221+24 BLL 12 24 24.1863956209 +24 36 23.500844570   17.93 17.37     ~ 114 0
8 QSO B1229+6430 BLL 12 31 31.3953946380 +64 14 18.288194641   18.36 17.62 14.3   ~ 121 2
9 QSO B1255+244 BLL 12 57 31.9330234281 +24 12 40.168674935     15.4 15.7   ~ 69 0
10 QSO B1426+428 BLL 14 28 32.6090831425 +42 40 21.050020627   16.95 16.45 14.4   ~ 447 2
11 QSO B1440+122 BLL 14 42 48.276582 +12 00 40.37487   18.34 17.63 15.2   ~ 133 3
12 QSO B1458+22 BLL 15 01 01.8350075608 +22 38 06.372083835   16.29 15.79     ~ 105 0
13 QSO B1552+20 BLL 15 54 24.1302300084 +20 11 25.402710408     17.70     ~ 84 0
14 4C 39.49 BLL 16 53 52.21668494 +39 45 36.6089458 14.09 14.15 13.29 8.26   ~ 1880 2
15 6C 172704+501607 BLL 17 28 18.6239898055 +50 13 10.472390025   16.55 15.97 12.95   ~ 313 1
16 3C 371 BLL 18 06 50.6803567107 +69 49 28.108152993   14.77 14.22 11.39   ~ 788 2
17 QSO B1853+671 BLL 18 53 52.0678730731 +67 13 55.017062425     16.4 17.1   ~ 36 1
18 QSO B1959+650 BLL 19 59 59.8525497024 +65 08 54.651170114     12.8 11.21   ~ 486 2
19 NAME BL Lac BLL 22 02 43.2913773726 +42 16 39.978417860   15.66 14.72     ~ 1977 1
20 ICRF J220417.6+044002 Sy1 22 04 17.6513714565 +04 40 02.051619965   16.20 15.2 10.2   ~ 176 2
21 QSO B2254+0727 BLL 22 57 17.30312249 +07 43 12.3024770   17.07 16.36     ~ 280 1
22 QSO B2326+174 BLL 23 29 03.3192654980 +17 43 30.522122687     16.8 16.7   ~ 31 1
23 QSO B2344+514 BLL 23 47 04.8376303689 +51 42 17.875387216     15.50 10.7   ~ 376 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2004A&A...424..107K and select 'bookmark this link' or equivalent in the popup menu


2019.12.13-08:45:59

© Université de Strasbourg/CNRS

    • Contact