Matches in SemOpenAlex for { <https://semopenalex.org/work/W3103474865> ?p ?o ?g. }
- W3103474865 endingPage "265" @default.
- W3103474865 startingPage "234" @default.
- W3103474865 abstract "We present first results from a spectroscopic survey designed to examine the metallicity and kinematics of individual red giant branch stars in the outer halo of the Andromeda spiral galaxy (M31). This study is based on multislit spectroscopy with the Keck II 10 m telescope and Low Resolution Imaging Spectrograph of the Ca II near-infrared triplet in 99 M31 halo candidates in a field at R = 19 kpc on the southeast minor axis with brightnesses from 20 < I < 22. The spectra are used to isolate M31 halo red giants from foreground Milky Way dwarf stars, faint compact background galaxies, and M31 disk giants. The observed distribution of radial velocities is well fitted by an equal mix of foreground Milky Way dwarf stars, drawn from a standard Galactic model and with velocities v ≲ 0 km s-1, and M31 halo giants represented by a Gaussian of width σ ∼ 150 km s-1 centered on its systemic velocity of v ≈ -300 km s-1. A secure sample of 29 M31 red giant stars is identified on the basis of radial velocity (v < -220 km s-1) and, in the case of four intermediate-velocity stars (-160 < v < -220 km s-1), broadband B-I color. For this sample of objects, there is rough agreement between the metallicities derived in independent ways: two different calibrations of the Ca II absorption-line strength and a photometric estimate based on fitting model stellar isochrones to an object's location in a (B-I, I) color-magnitude diagram. The [Fe/H] distribution of M31 halo giants has an rms spread of at least 0.6 dex and spans the ≳2 dex range over which the abundance measurement methods are calibrated. The mean/median metallicity of the M31 halo is about ⟨[Fe/H]⟩ = -1.9 to -1.1 dex (depending on the details of metallicity calibration and sample selection) and possibly higher: the high-metallicity end of the distribution is poorly constrained by our data since the selection function for the secure M31 sample excludes over 80% of the giants in solar/supersolar metallicity range. Possible reasons are explored for the apparent discrepancy between the mean [Fe/H] found in our spectroscopic survey (corrected for metallicity selection bias) and the slightly higher mean values found in earlier photometric studies. Field halo red giants in M31 appear to be somewhat more metal-rich on average than their Milky Way counterparts. The M31 halo [Fe/H] distribution is comparable to that of M31 globular clusters, Galactic globular clusters, and Local Group dwarf satellite galaxies. The data in this 19 kpc outer halo field are broadly consistent with a scenario in which the halo is built from the accretion of small stellar subsystems. There are four stars in the secure M31 sample that have particularly strong Ca II lines, indicating solar metallicity, at a common velocity of ≈-340 km s-1 close to the galaxy's systemic velocity, similar to what might be expected for M31 disk giants on the minor axis. An extrapolation of the inner disk brightness profile, however, falls far short of accounting for these four stars—the disk would instead have to be very large (Rdisk ≳ 80 kpc) and/or warped. More likely, these four stars represent a metal-rich debris trail from a past accretion event in the halo." @default.
- W3103474865 created "2020-11-23" @default.
- W3103474865 creator A5018014899 @default.
- W3103474865 creator A5051126966 @default.
- W3103474865 date "2002-07-01" @default.
- W3103474865 modified "2023-09-26" @default.
- W3103474865 title "Metallicity and Kinematics of M31’s Outer Stellar Halo from a Keck Spectroscopic Survey" @default.
- W3103474865 cites W1576195090 @default.
- W3103474865 cites W1658854440 @default.
- W3103474865 cites W1710780480 @default.
- W3103474865 cites W1966714030 @default.
- W3103474865 cites W1970841308 @default.
- W3103474865 cites W1972341431 @default.
- W3103474865 cites W1974309328 @default.
- W3103474865 cites W1978429898 @default.
- W3103474865 cites W1978641702 @default.
- W3103474865 cites W1978769139 @default.
- W3103474865 cites W1979886222 @default.
- W3103474865 cites W1980639774 @default.
- W3103474865 cites W1985735412 @default.
- W3103474865 cites W1986010423 @default.
- W3103474865 cites W1988006098 @default.
- W3103474865 cites W1989721545 @default.
- W3103474865 cites W1990480799 @default.
- W3103474865 cites W1993673013 @default.
- W3103474865 cites W1998216926 @default.
- W3103474865 cites W2008204335 @default.
- W3103474865 cites W2009182838 @default.
- W3103474865 cites W2010642725 @default.
- W3103474865 cites W2013013065 @default.
- W3103474865 cites W2013962707 @default.
- W3103474865 cites W2015295900 @default.
- W3103474865 cites W2026215318 @default.
- W3103474865 cites W2027388357 @default.
- W3103474865 cites W2038626497 @default.
- W3103474865 cites W2041251533 @default.
- W3103474865 cites W2044093857 @default.
- W3103474865 cites W2045631460 @default.
- W3103474865 cites W2050520819 @default.
- W3103474865 cites W2066406099 @default.
- W3103474865 cites W2070196742 @default.
- W3103474865 cites W2070446540 @default.
- W3103474865 cites W2073123016 @default.
- W3103474865 cites W2075970816 @default.
- W3103474865 cites W2076226138 @default.
- W3103474865 cites W2081115376 @default.
- W3103474865 cites W2082695574 @default.
- W3103474865 cites W2083954823 @default.
- W3103474865 cites W2085066178 @default.
- W3103474865 cites W2089017458 @default.
- W3103474865 cites W2089822034 @default.
- W3103474865 cites W2090495550 @default.
- W3103474865 cites W2091221609 @default.
- W3103474865 cites W2091905312 @default.
- W3103474865 cites W2104138988 @default.
- W3103474865 cites W2111587098 @default.
- W3103474865 cites W2111817932 @default.
- W3103474865 cites W2117163700 @default.
- W3103474865 cites W2125712657 @default.
- W3103474865 cites W2134770831 @default.
- W3103474865 cites W2135497536 @default.
- W3103474865 cites W2161627373 @default.
- W3103474865 cites W2165084703 @default.
- W3103474865 cites W2167635287 @default.
- W3103474865 cites W2326817105 @default.
- W3103474865 cites W2601053151 @default.
- W3103474865 cites W2963982848 @default.
- W3103474865 cites W3021233282 @default.
- W3103474865 cites W3098137810 @default.
- W3103474865 cites W3098656264 @default.
- W3103474865 cites W3098793616 @default.
- W3103474865 cites W3099435437 @default.
- W3103474865 cites W3099665156 @default.
- W3103474865 cites W3101604497 @default.
- W3103474865 cites W3102875757 @default.
- W3103474865 cites W3103474865 @default.
- W3103474865 cites W3105487931 @default.
- W3103474865 cites W3125543183 @default.
- W3103474865 doi "https://doi.org/10.1086/341175" @default.
- W3103474865 hasPublicationYear "2002" @default.
- W3103474865 type Work @default.
- W3103474865 sameAs 3103474865 @default.
- W3103474865 citedByCount "49" @default.
- W3103474865 countsByYear W31034748652012 @default.
- W3103474865 countsByYear W31034748652013 @default.
- W3103474865 countsByYear W31034748652014 @default.
- W3103474865 countsByYear W31034748652015 @default.
- W3103474865 countsByYear W31034748652017 @default.
- W3103474865 countsByYear W31034748652018 @default.
- W3103474865 countsByYear W31034748652020 @default.
- W3103474865 crossrefType "journal-article" @default.
- W3103474865 hasAuthorship W3103474865A5018014899 @default.
- W3103474865 hasAuthorship W3103474865A5051126966 @default.
- W3103474865 hasBestOaLocation W31034748651 @default.
- W3103474865 hasConcept C113461152 @default.
- W3103474865 hasConcept C121332964 @default.
- W3103474865 hasConcept C1276947 @default.
- W3103474865 hasConcept C150846664 @default.