A DOUBLE MAIN SEQUENCE IN THE GLOBULAR CLUSTER NGC 6397

被引：90

作者：

Milone, A. P. ^{[1
,2
]}

Marino, A. F. ^{[3
]}

Piotto, G. ^{[4
,5
]}

Bedin, L. R. ^{[6
]}

Anderson, J. ^{[6
]}

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

Cassisi, S. ^{[7
]}

Rich, R. M. ^{[8
]}

机构：

[1] Inst Astrofis Canarias, E-38200 San Cristobal la Laguna, Tenerife, Spain

[2] Univ La Laguna, Dept Astrophys, E-38200 San Cristobal la Laguna, Tenerife, Spain

[3] Max Planck Inst Astrophys, D-85741 Garching, Germany

[4] Univ Padua, Dipartimento Astron, I-35122 Padua, Italy

[5] INAF Osservatorio Astron Padova, I-35122 Padua, Italy

[6] Space Telescope Sci Inst, Baltimore, MD 21218 USA

[7] INAF Osservatorio Astron Collurania, I-64100 Teramo, Italy

[8] Univ Calif Los Angeles, Div Astron & Astrophys, Los Angeles, CA 90095 USA

来源：

ASTROPHYSICAL JOURNAL | 2012年 / 745卷 / 01期

关键词：

globular clusters: individual (NGC 6397); stars: Population II; MULTIPLE STELLAR POPULATIONS; ADVANCED CAMERA; OMEGA-CENTAURI; GIANT STARS; ACS SURVEY; ABUNDANCES; NGC-6397; BRANCH; ASTROMETRY; NGC-2808;

D O I：

10.1088/0004-637X/745/1/27

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

High-precision multi-band Hubble Space Telescope (HST) photometry reveals that the main sequence of the globular cluster NGC 6397 splits into two components, containing similar to 30% and similar to 70% of the stars. This double sequence is consistent with the idea that the cluster hosts two stellar populations: (1) a primordial population that has a composition similar to field stars, containing similar to 30% of the stars, and (2) a second generation with enhanced sodium and nitrogen, depleted carbon and oxygen, and a slightly enhanced helium abundance (Delta Y similar to 0.01). We examine the color difference between the two sequences across a variety of color baselines and find that the second sequence is anomalously faint in m(F336W). Theoretical isochrones indicate that this could be due to NH depletion.

引用

页数：10

共 50 条

[41] The dynamics of multiple populations in the globular cluster NGC 6362
Miholics, Meghan
Webb, Jeremy J.
Sills, Alison
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2015, 454 (02) : 2166 - 2172
[42] THE BIZARRE CHEMICAL INVENTORY OF NGC 2419, AN EXTREME OUTER HALO GLOBULAR CLUSTER
Cohen, Judith G.
Kirby, Evan N.
ASTROPHYSICAL JOURNAL, 2012, 760 (01)
[43] On the origin of the stellar halo and multiple stellar populations in the globular cluster NGC 1851
Bekki, Kenji
Yong, David
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2012, 419 (03) : 2063 - 2076
[44] ON THE SERENDIPITOUS DISCOVERY OF A Li-RICH GIANT IN THE GLOBULAR CLUSTER NGC 362
D'Orazi, Valentina
Gratton, Raffaele G.
Angelou, George C.
Bragaglia, Angela
Carretta, Eugenio
Lattanzio, John C.
Lucatello, Sara
Momany, Yazan
Sollima, Antonio
ASTROPHYSICAL JOURNAL LETTERS, 2015, 801 (02)
[45] NGC 5824: a luminous outer halo globular cluster with an intrinsic abundance spread
Da Costa, G. S.
Held, E. V.
Saviane, I.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2014, 438 (04) : 3507 - 3520
[46] Helium and multiple populations in the massive globular cluster NGC 6266 (M 62)
Milone, A. P.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2015, 446 (02) : 1672 - 1684
[47] A sequence of nitrogen-rich very red giants in the globular cluster NGC 1851
Carretta, Eugenio
D'Orazi, Valentina
Gratton, Raffaele G.
Lucatello, Sara
ASTRONOMY & ASTROPHYSICS, 2014, 563
[48] The halo plus cluster system of the Galactic globular cluster NGC 1851a∼...
Marino, A. F.
Milone, A. P.
Yong, D.
Dotter, A.
Da Costa, G.
Asplund, M.
Jerjen, H.
Mackey, D.
Norris, J.
Cassisi, S.
Sbordone, L.
Stetson, P. B.
Weiss, A.
Aparicio, A.
Bedin, L. R.
Lind, K.
Monelli, M.
Piotto, G.
Angeloni, R.
Buonanno, R.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2014, 442 (04) : 3044 - 3064
[49] Signatures of intrinsic Li depletion and Li-Na anti-correlation in the metal-poor globular cluster NGC 6397
Lind, K.
Primas, F.
Charbonnel, C.
Grundahl, F.
Asplund, M.
ASTRONOMY & ASTROPHYSICS, 2009, 503 (02) : 545 - 557
[50] Atomic diffusion and mixing in old stars II. Observations of stars in the globular cluster NGC 6397 with VLT/FLAMES-GIRAFFE
Lind, K.
Korn, A. J.
Barklem, P. S.
Grundahl, F.
ASTRONOMY & ASTROPHYSICS, 2008, 490 (02) : 777 - U82

← 1 2 3 4 5 →