Revealing the nature of star forming blue early-type galaxies at low redshift

被引：17

作者：

George, Koshy ^{[1
]}

Zingade, Kshama ^{[2
]}

机构：

[1] Indian Inst Astrophys, Bangalore 560034, Karnataka, India

[2] Indian Inst Technol, Madras 600036, Tamil Nadu, India

来源：

ASTRONOMY & ASTROPHYSICS | 2015年 / 583卷

关键词：

galaxies: evolution; galaxies: elliptical and lenticular; cD; galaxies: interactions; galaxies: star formation; ELLIPTIC GALAXIES; ATLAS(3D) PROJECT; COLD GAS; POPULATION; EVOLUTION; PARAMETERS; MORPHOLOGY; COMBO-17; SKY; I;

D O I：

10.1051/0004-6361/201424826

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Context. Star forming early-type galaxies with blue optical colours at low redshift can be used to test our current understanding of galaxy formation and evolution. Aims. We want to reveal the fuel and triggering mechanism for star formation in these otherwise passively evolving red and dead stellar systems. Methods. We undertook an optical and ultraviolet study of 55 star forming blue early-type galaxies, searching for signatures of recent interactions that could be driving the molecular gas into the galaxy and potentially triggering the star formation. Results. We report here our results on star forming blue early-type galaxies with tidal trails and in close proximity to neighbouring galaxies that are evidence of ongoing or recent interactions between galaxies. There are 12 galaxies with close companions with similar redshifts, among which two galaxies are having ongoing interactions that potentially trigger the star formation. Two galaxies show a jet feature that could be due to the complete tidal disruption of the companion galaxy. The interacting galaxies have high star formation rates and very blue optical colours. Galaxies with no companion could have undergone a minor merger in the recent past. Conclusions. The recent or ongoing interaction with a gas-rich neighbouring galaxy could be responsible for bringing cold gas to an otherwise passively evolving early-type galaxy. The sudden gas supply could trigger the star formation, eventually creating a blue early-type galaxy. The galaxies with ongoing tidal interaction are blue and star forming, thereby implying that blue early-type galaxies can exist even when the companion is on flyby so does not end up in a merger.

引用

页数：6

共 27 条

[1] THE SEVENTH DATA RELEASE OF THE SLOAN DIGITAL SKY SURVEY [J].

Abazajian, Kevork N. ;

Adelman-McCarthy, Jennifer K. ;

Agueros, Marcel A. ;

Allam, Sahar S. ;

Prieto, Carlos Allende ;

An, Deokkeun ;

Anderson, Kurt S. J. ;

Anderson, Scott F. ;

Annis, James ;

Bahcall, Neta A. ;

Bailer-Jones, C. A. L. ;

Barentine, J. C. ;

Bassett, Bruce A. ;

Becker, Andrew C. ;

Beers, Timothy C. ;

Bell, Eric F. ;

Belokurov, Vasily ;

Berlind, Andreas A. ;

Berman, Eileen F. ;

Bernardi, Mariangela ;

Bickerton, Steven J. ;

Bizyaev, Dmitry ;

Blakeslee, John P. ;

Blanton, Michael R. ;

Bochanski, John J. ;

Boroski, William N. ;

Brewington, Howard J. ;

Brinchmann, Jarle ;

Brinkmann, J. ;

Brunner, Robert J. ;

Budavari, Tamas ;

Carey, Larry N. ;

Carliles, Samuel ;

Carr, Michael A. ;

Castander, Francisco J. ;

Cinabro, David ;

Connolly, A. J. ;

Csabai, Istvan ;

Cunha, Carlos E. ;

Czarapata, Paul C. ;

Davenport, James R. A. ;

de Haas, Ernst ;

Dilday, Ben ;

Doi, Mamoru ;

Eisenstein, Daniel J. ;

Evans, Michael L. ;

Evans, N. W. ;

Fan, Xiaohui ;

Friedman, Scott D. ;

Frieman, Joshua A. .

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2009, 182 (02) :543-558

[2] Quantifying the bimodal color-magnitude distribution of galaxies [J].

Baldry, IK ;

Glazebrook, K ;

Brinkmann, J ;

Ivezic, Z ;

Lupton, RH ;

Nichol, RC ;

Szalay, AS .

ASTROPHYSICAL JOURNAL, 2004, 600 (02) :681-694

[3] CLASSIFICATION PARAMETERS FOR THE EMISSION-LINE SPECTRA OF EXTRA-GALACTIC OBJECTS [J].

BALDWIN, JA ;

PHILLIPS, MM .

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC, 1981, 93 (551) :5-19

[4] THE FIRST SURVEY - FAINT IMAGES OF THE RADIO SKY AT 20 CENTIMETERS [J].

BECKER, RH ;

WHITE, RL ;

HELFAND, DJ .

ASTROPHYSICAL JOURNAL, 1995, 450 (02) :559-577

[5] Nearly 5000 distant early-type galaxies in combo-17:: A red sequence and its evolution since z ∼ 1 [J].

Bell, EF ;

Wolf, C ;

Meisenheimer, K ;

Rix, HW ;

Borch, A ;

Dye, S ;

Kleinheinrich, M ;

Wisotzki, L ;

McIntosh, DH .

ASTROPHYSICAL JOURNAL, 2004, 608 (02) :752-767

[6] The evolving luminosity function of red galaxies [J].

Brown, Michael J. I. ;

Dey, Arjun ;

Jannuzi, Buell T. ;

Brand, Kate ;

Benson, Andrew J. ;

Brodwin, Mark ;

Croton, Darren J. ;

Eisenhardt, Peter R. .

ASTROPHYSICAL JOURNAL, 2007, 654 (02) :858-877

[7] THE PROPAGATION OF UNCERTAINTIES IN STELLAR POPULATION SYNTHESIS MODELING. I. THE RELEVANCE OF UNCERTAIN ASPECTS OF STELLAR EVOLUTION AND THE INITIAL MASS FUNCTION TO THE DERIVED PHYSICAL PROPERTIES OF GALAXIES [J].

Conroy, Charlie ;

Gunn, James E. ;

White, Martin .

ASTROPHYSICAL JOURNAL, 2009, 699 (01) :486-506

[8] SPECTROSCOPY AND PHOTOMETRY OF ELLIPTIC GALAXIES .1. A NEW DISTANCE ESTIMATOR [J].

DRESSLER, A ;

LYNDENBELL, D ;

BURSTEIN, D ;

DAVIES, RL ;

FABER, SM ;

TERLEVICH, RJ ;

WEGNER, G .

ASTROPHYSICAL JOURNAL, 1987, 313 (01) :42-58

[9] GALAXY MORPHOLOGY IN RICH CLUSTERS - IMPLICATIONS FOR THE FORMATION AND EVOLUTION OF GALAXIES [J].

DRESSLER, A .

ASTROPHYSICAL JOURNAL, 1980, 236 (02) :351-365

[10] Galaxy luminosity functions to z ∼ 1 from deep2 and combo-17:: Implications for red galaxy formation [J].

Faber, S. M. ;

Willmer, C. N. A. ;

Wolf, C. ;

Koo, D. C. ;

Weiner, B. J. ;

Newman, J. A. ;

Im, M. ;

Coil, A. L. ;

Conroy, C. ;

Cooper, M. C. ;

Davis, M. ;

Finkbeiner, D. P. ;

Gerke, B. F. ;

Gebhardt, K. ;

Groth, E. J. ;

Guhathakurta, P. ;

Harker, J. ;

Kaiser, N. ;

Kassin, S. ;

Kleinheinrich, M. ;

Konidaris, N. P. ;

Kron, R. G. ;

Lin, L. ;

Luppino, G. ;

Madgwick, D. S. ;

Meisenheimer, K. ;

Noeske, K. G. ;

Phillips, A. C. ;

Sarajedini, V. L. ;

Schiavon, R. P. ;

Simard, L. ;

Szalay, A. S. ;

Vogt, N. P. ;

Yan, R. .

ASTROPHYSICAL JOURNAL, 2007, 665 (01) :265-294

← 1 2 3 →