Abstract
As part of the Spaghetti Project Survey, we have detected a concentration of giant stars well above expectations for a smooth halo model. The position (l ∼ 350°, b ∼ 50°) and distance (∼50 kpc) of this concentration match those of the northern overdensity detected by the Sloan Digital Sky Survey. We find additional evidence for structure at ∼80 kpc in the same direction. We present radial velocities for many of these stars, including the first published results from the 6.5 m Magellan telescope. The radial velocities for stars in these structures are in excellent agreement with models of the dynamical evolution of the Sagittarius dwarf tidal debris, whose center is 60° away. The metallicity of stars in these streams is lower than that of the main body of the Sgr dwarf, which may indicate a radial metallicity gradient prior to disruption.
| Original language | English (US) |
|---|---|
| Journal | Astrophysical Journal |
| Volume | 555 |
| Issue number | 1 PART 2 |
| DOIs | |
| State | Published - Jul 1 2001 |
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Keywords
- Galaxy: Evolution
- Galaxy: Formation
- Galaxy: Halo
- Galaxy: Stellar content
ASJC Scopus subject areas
- Space and Planetary Science
Cite this
Mapping the galactic halo. V. Sagittarius dwarf spheroidal tidal debris 60° from the main body. / Dohm-Palmer, Robbie C.; Helmi, Amina; Morrison, Heather; Mateo, Mario; Olszewski, Edward W; Harding, Paul; Freeman, Kenneth C.; Norris, John; Shectman, Stephen A.
In: Astrophysical Journal, Vol. 555, No. 1 PART 2, 01.07.2001.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Mapping the galactic halo. V. Sagittarius dwarf spheroidal tidal debris 60° from the main body
AU - Dohm-Palmer, Robbie C.
AU - Helmi, Amina
AU - Morrison, Heather
AU - Mateo, Mario
AU - Olszewski, Edward W
AU - Harding, Paul
AU - Freeman, Kenneth C.
AU - Norris, John
AU - Shectman, Stephen A.
PY - 2001/7/1
Y1 - 2001/7/1
N2 - As part of the Spaghetti Project Survey, we have detected a concentration of giant stars well above expectations for a smooth halo model. The position (l ∼ 350°, b ∼ 50°) and distance (∼50 kpc) of this concentration match those of the northern overdensity detected by the Sloan Digital Sky Survey. We find additional evidence for structure at ∼80 kpc in the same direction. We present radial velocities for many of these stars, including the first published results from the 6.5 m Magellan telescope. The radial velocities for stars in these structures are in excellent agreement with models of the dynamical evolution of the Sagittarius dwarf tidal debris, whose center is 60° away. The metallicity of stars in these streams is lower than that of the main body of the Sgr dwarf, which may indicate a radial metallicity gradient prior to disruption.
AB - As part of the Spaghetti Project Survey, we have detected a concentration of giant stars well above expectations for a smooth halo model. The position (l ∼ 350°, b ∼ 50°) and distance (∼50 kpc) of this concentration match those of the northern overdensity detected by the Sloan Digital Sky Survey. We find additional evidence for structure at ∼80 kpc in the same direction. We present radial velocities for many of these stars, including the first published results from the 6.5 m Magellan telescope. The radial velocities for stars in these structures are in excellent agreement with models of the dynamical evolution of the Sagittarius dwarf tidal debris, whose center is 60° away. The metallicity of stars in these streams is lower than that of the main body of the Sgr dwarf, which may indicate a radial metallicity gradient prior to disruption.
KW - Galaxy: Evolution
KW - Galaxy: Formation
KW - Galaxy: Halo
KW - Galaxy: Stellar content
UR - http://www.scopus.com/inward/record.url?scp=0035402266&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035402266&partnerID=8YFLogxK
U2 - 10.1086/321734
DO - 10.1086/321734
M3 - Article
AN - SCOPUS:0035402266
VL - 555
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 1 PART 2
ER -