Digging deeper into the Southern skies: a compact Milky Way companion discovered in first-year Dark Energy Survey data

被引：53

作者：

Luque, E. ^{[1
,2
]}

Queiroz, A. ^{[1
,2
]}

Santiago, B. ^{[1
,2
]}

Pieres, A. ^{[1
,2
]}

Balbinot, E. ^{[2
,3
]}

Bechtol, K. ^{[4
]}

Drlica-Wagner, A. ^{[5
]}

Fausti Neto, A. ^{[2
]}

da Costa, L. N. ^{[2
,6
]}

Maia, M. A. G. ^{[2
,6
]}

Yanny, B. ^{[5
]}

Abbott, T. ^{[7
]}

Allam, S. ^{[5
]}

Benoit-Levy, A. ^{[8
]}

Bertin, E. ^{[9
,10
]}

Brooks, D. ^{[8
]}

Buckley-Geer, E. ^{[5
]}

Burke, D. L. ^{[11
,12
]}

Carnero Rosell, A. ^{[2
,6
]}

Kind, M. Carrasco ^{[13
,14
]}

Carretero, J. ^{[15
,16
]}

Cunha, C. E. ^{[11
]}

Desai, S. ^{[17
,18
]}

Diehl, H. T. ^{[5
]}

Dietrich, J. P. ^{[17
,18
]}

Eifler, T. F. ^{[19
,20
]}

Finley, D. A. ^{[5
]}

Flaugher, B. ^{[5
]}

Fosalba, P. ^{[15
]}

Frieman, J. ^{[5
,21
]}

Gerdes, D. W. ^{[22
]}

Gruen, D. ^{[23
,24
]}

Gutierrez, G. ^{[5
]}

Honscheid, K. ^{[25
,26
]}

James, D. J. ^{[7
]}

Kuehn, K. ^{[27
]}

Kuropatkin, N. ^{[5
]}

Lahav, O. ^{[8
]}

Li, T. S. ^{[28
,29
]}

March, M. ^{[19
]}

Marshall, J. L. ^{[28
,29
]}

Martini, P. ^{[25
,30
]}

Miquel, R. ^{[16
,31
]}

Neilsen, E. ^{[5
]}

Nichol, R. C. ^{[32
]}

Nord, B. ^{[5
]}

Ogando, R. ^{[2
,6
]}

Plazas, A. A. ^{[20
]}

Romer, A. K. ^{[33
]}

Roodman, A. ^{[11
,12
]}

机构：

[1] Univ Fed Rio Grande do Sul, Inst Fis, Caixa Postal 15051, BR-91501970 Porto Alegre, RS, Brazil

[2] Lab Interinst E Astron LIneA, Rua Gal Jose Cristino 77, BR-20921400 Rio De Janeiro, RJ, Brazil

[3] Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England

[4] Univ Chicago, Kavli Inst Cosmol Phys, Chicago, IL 60637 USA

[5] Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA

[6] Observ Nacl, Rua Gal Jose Cristino 77, BR-20921400 Rio De Janeiro, RJ, Brazil

[7] Cerro Tololo Interamer Observ, Natl Opt Astron Observ, Casilla 603, La Serena, Chile

[8] UCL, Dept Phys & Astron, Gower St, London WC1E 6BT, England

[9] Inst Astrophys, CNRS, UMR 7095, F-75014 Paris, France

[10] Univ Paris 06, Sorbonne Univ, UMR 7095, Inst Astrophys Paris, F-75014 Paris, France

[11] Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, POB 2450, Stanford, CA 94305 USA

[12] SLAC Natl Accelerator Lab, Menlo Pk, CA 94025 USA

[13] Univ Illinois, Dept Astron, 1002 W Green St, Urbana, IL 61801 USA

[14] Univ Illinois, Natl Ctr Supercomp Applicat, 1205 W Clark St, Urbana, IL 61801 USA

[15] CSIC, IEEC, Inst Ciencies Espai, Campus UAB,Carrer Can Magrans S-N, E-08193 Barcelona, Spain

[16] Univ Autonoma Barcelona, Inst Fis Altes Energies, E-08193 Barcelona, Spain

[17] Excellence Cluster Universe, Boltzmannstr 2, D-85748 Garching, Germany

[18] Univ Munich, Fac Phys, Scheinerstr 1, D-81679 Munich, Germany

[19] Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA

[20] CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA

[21] Univ Chicago, Kavli Inst Cosmol Phys, Chicago, IL 60637 USA

[22] Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA

[23] Max Planck Inst Extraterr Phys, Giessenbachstr, D-85748 Garching, Germany

[24] Univ Munich, Univ Sternwarte, Fak Phys, Scheinerstr 1, D-81679 Munich, Germany

[25] Ohio State Univ, Ctr Cosmol & Astroparticle Phys, Columbus, OH 43210 USA

[26] Ohio State Univ, Dept Phys, 174 W 18th Ave, Columbus, OH 43210 USA

[27] Australian Astron Observ, N Ryde, NSW 2113, Australia

[28] Texas A&M Univ, George P & Cynthia Woods Mitchell Inst Fundamenta, College Stn, TX 77843 USA

[29] Texas A&M Univ, Dept Phys & Astron, College Stn, TX 77843 USA

[30] Ohio State Univ, Dept Astron, 174 W 18Th Ave, Columbus, OH 43210 USA

[31] Inst Catalana Recerca & Estudis Avancats, E-08010 Barcelona, Spain

[32] Univ Portsmouth, Inst Cosmol & Gravitat, Portsmouth PO1 3FX, Hants, England

[33] Univ Sussex, Dept Phys & Astron, Pevensey Bldg, Brighton BN1 9QH, E Sussex, England

[34] Ctr Invest Energet Medioambientales & Tecnol CIEM, Madrid, Spain

[35] Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 2016年 / 458卷 / 01期

基金：

美国国家科学基金会;

关键词：

globular clusters: general; globular clusters: individual (DES 1); galaxies: dwarf; DIGITAL SKY SURVEY; PAN-STARRS1 3-PI SURVEY; ULTRA-FAINT SATELLITES; GLOBULAR-CLUSTERS; STAR CLUSTER; PROPER MOTIONS; DWARF GALAXIES; DATA RELEASE; HALO; CONSTELLATION;

D O I：

10.1093/mnras/stw302

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We use the first-year Dark Energy Survey (DES) data down to previously unprobed photometric depths to search for stellar systems in the Galactic halo, therefore complementing the previous analysis of the same data carried out by our group earlier this year. Our search is based on a matched filter algorithm that produces stellar density maps consistent with stellar population models of various ages, metallicities, and distances over the survey area. The most conspicuous density peaks in these maps have been identified automatically and ranked according to their significance and recurrence for different input models. We report the discovery of one additional stellar system besides those previously found by several authors using the same first-year DES data. The object is compact, and consistent with being dominated by an old and metal-poor population. DES 1 is found at high significance and appears in the DES images as a compact concentration of faint blue point sources. Assuming different spatial profile parameterizations, the best-fitting heliocentric distance and total absolute magnitude in the range of 77.6-87.1 kpc and -3.00 less than or similar to M-V less than or similar to -2.21, respectively. The half-light radius of this object, r(h) similar to 10 pc and total luminosity are consistent with it being a low-mass halo cluster. It is also found to have a very elongated shape (epsilon similar to 0.57). In addition, our deeper probe of DES first-year data confirms the recently reported satellite galaxy candidate Horologium II as a significant stellar overdensity. We also infer its structural properties and compare them to those reported in the literature.

引用

页码：603 / 612

页数：10

共 48 条

[1]

Abbott T., 2005, ARXIV ASTROPHYSICS E

[2]

[Anonymous], ARXIV151201032

[3]

[Anonymous], 2000, Statistical Inference in Science

[4] A NEW MILKY WAY HALO STAR CLUSTER IN THE SOUTHERN GALACTIC SKY [J].

Balbinot, E. ;

Santiago, B. X. ;

da Costa, L. ;

Maia, M. A. G. ;

Majewski, S. R. ;

Nidever, D. ;

Rocha-Pinto, H. J. ;

Thomas, D. ;

Wechsler, R. H. ;

Yanny, B. .

ASTROPHYSICAL JOURNAL, 2013, 767 (02)

[5] The tidal tails of NGC 2298 [J].

Balbinot, Eduardo ;

Santiago, Basilio X. ;

da Costa, Luiz N. ;

Makler, Martin ;

Maia, Marcio A. G. .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2011, 416 (01) :393-402

[6] EIGHT NEW MILKY WAY COMPANIONS DISCOVERED IN FIRST-YEAR DARK ENERGY SURVEY DATA [J].

Bechtol, K. ;

Drlica-Wagner, A. ;

Balbinot, E. ;

Pieres, A. ;

Simon, J. D. ;

Yanny, B. ;

Santiago, B. ;

Wechsler, R. H. ;

Frieman, J. ;

Walker, A. R. ;

Williams, P. ;

Rozo, E. ;

Rykoff, E. S. ;

Queiroz, A. ;

Luque, E. ;

Benoit-Levy, A. ;

Tucker, D. ;

Sevilla, I. ;

Gruendl, R. A. ;

da Costa, L. N. ;

Fausti Neto, A. ;

Maia, M. A. G. ;

Abbott, T. ;

Allam, S. ;

Armstrong, R. ;

Bauer, A. H. ;

Bernstein, G. M. ;

Bernstein, R. A. ;

Bertin, E. ;

Brooks, D. ;

Buckley-Geer, E. ;

Burke, D. L. ;

Carnero Rosell, A. ;

Castander, F. J. ;

Covarrubias, R. ;

D'Andrea, C. B. ;

DePoy, D. L. ;

Desai, S. ;

Diehl, H. T. ;

Eifler, T. F. ;

Estrada, J. ;

Evrard, A. E. ;

Fernandez, E. ;

Finley, D. A. ;

Flaugher, B. ;

Gaztanaga, E. ;

Gerdes, D. ;

Girardi, L. ;

Gladders, M. ;

Gruen, D. .

ASTROPHYSICAL JOURNAL, 2015, 807 (01)

[7] BIG FISH, LITTLE FISH: TWO NEW ULTRA-FAINT SATELLITES OF THE MILKY WAY [J].

Belokurov, V. ;

Walker, M. G. ;

Evans, N. W. ;

Gilmore, G. ;

Irwin, M. J. ;

Just, D. ;

Koposov, S. ;

Mateo, M. ;

Olszewski, E. ;

Watkins, L. ;

Wyrzykowski, L. .

ASTROPHYSICAL JOURNAL LETTERS, 2010, 712 (01) :L103-L106

[8] SExtractor: Software for source extraction [J].

Bertin, E ;

Arnouts, S .

ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES, 1996, 117 (02) :393-404

[9] Dynamical analysis of nearby clusters Automated astrometry from the ground: precision proper motions over a wide field [J].

Bouy, H. ;

Bertin, E. ;

Moraux, E. ;

Cuillandre, J. -C. ;

Bouvier, J. ;

Barrado, D. ;

Solano, E. ;

Bayo, A. .

ASTRONOMY & ASTROPHYSICS, 2013, 554

[10] parsec: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code [J].

Bressan, Alessandro ;

Marigo, Paola ;

Girardi, Leo ;

Salasnich, Bernardo ;

Dal Cero, Claudia ;

Rubele, Stefano ;

Nanni, Ambra .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2012, 427 (01) :127-145

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