Discovery of a New, Polar-Orbiting Debris Stream in the Milky Way Stellar Halo

Journal Article · Mon Jun 01 04:00:00 EDT 2009 · Astrophys.J.700:L61-L64,2009

DOI:https://doi.org/10.1088/0004-637X/700/2/L61· OSTI ID:964024

Newberg, Heidi Jo; Yanny, Brian; Willett, Benjamin A

We show that there is a low metallicity tidal stream that runs along l = 143{sup o} in the South Galactic Cap, about 34 kpc from the Sun, discovered from SEGUE stellar velocities. Since the most concentrated detections are in the Cetus constellation, and the orbital path is nearly polar, we name it the Cetus Polar Stream (CPS). Although it is spatially coincident with the Sgr dwarf trailing tidal tail at b = -70{sup o}, the metallicities ([Fe/H] = -2.1), ratio of blue straggler to blue horizontal branch stars, and velocities of the CPS stars differ from Sgr. Some CPS stars may contaminate previous samples of Sgr dwarf tidal debris. The unusual globular cluster NGC 5824 is located along an orbit fit to the CPS, with the correct radial velocity.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-07CH11359
• OSTI ID: 964024
• Report Number(s): FERMILAB-PUB-09-357-A-CD; arXiv eprint number arXiv:0906.3291
• Journal Information: Astrophys.J.700:L61-L64,2009, Journal Name: Astrophys.J.700:L61-L64,2009 Journal Issue: 2 Vol. 700; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
Astrophysics
MILKY WAY
RADIAL VELOCITY
STARS
SUN