Verne V. Smith
A5007265287- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Astronomical and nuclear sciences
- History and Developments in Astronomy
- Atmospheric Ozone and Climate
- Galaxies: Formation, Evolution, Phenomena
- Adaptive optics and wavefront sensing
- Nuclear physics research studies
- Astrophysical Phenomena and Observations
- Solar and Space Plasma Dynamics
- Geophysics and Gravity Measurements
- Nuclear Physics and Applications
- Space Exploration and Technology
- Spectroscopy and Laser Applications
- Planetary Science and Exploration
- Calibration and Measurement Techniques
- Molecular Spectroscopy and Structure
- Isotope Analysis in Ecology
- Pulsars and Gravitational Waves Research
- High-pressure geophysics and materials
- Inertial Sensor and Navigation
Community Science and Data Center
2021-2024
NSF’s NOIRLab
2020-2024
Sorbonne Université
2022-2024
Centre National de la Recherche Scientifique
2022-2024
Institut d'Astrophysique de Paris
2022-2024
Kitt Peak National Observatory
2013-2022
Optica
2013-2022
Max Planck Institute for Astronomy
2019
Max Planck Society
2019
University of Arizona
2013-2017
The Apache Point Observatory Galactic Evolution Experiment (APOGEE), one of the programs in Sloan Digital Sky Survey III (SDSS-III), has now completed its systematic, homogeneous spectroscopic survey sampling all major populations Milky Way. After a three year observing campaign on 2.5-m Telescope, APOGEE collected half million high resolution (R~22,500), S/N (>100), infrared (1.51-1.70 microns) spectra for 146,000 stars, with time series information via repeat visits to most these stars....
Using a sample of 69,919 red giants from the SDSS-III/APOGEE Data Release 12, we measure distribution stars in [α/Fe] versus [Fe/H] plane and metallicity functions (MDFs) across an unprecedented volume Milky Way disk, with radius 3 < R 15 kpc height kpc. Stars inner disk (R 5 kpc) lie along single track [Fe/H], starting α-enhanced, metal-poor ending at ∼ 0 +0.4. At larger radii find two distinct sequences space, roughly solar-α sequence that spans decade high-α merges low-α super-solar...
Forty years ago Burbidge, Fowler, and Hoyle combined what we would now call fragmentary evidence from nuclear physics, stellar evolution the abundances of elements isotopes in solar system as well a few stars into synthesis remarkable ingenuity. Their review provided foundation for forty research all aspects low energy experiments theory, modeling over wide range mass composition, abundance studies many hundreds stars, which have shown distinct processes suggested by B${}^{2}$FH. In this...
We measure the Milky Way's rotation curve over Galactocentric range 4 kpc ≲ R 14 from first year of data Apache Point Observatory Galactic Evolution Experiment. model line-of-sight velocities 3365 stars in fields with b = 0° between 30° ⩽ l 210° out to distances 10 using an axisymmetric kinematical that includes a correction for asymmetric drift warm tracer population (σR ≈ 35 km s−1). determine local value circular velocity be Vc(R0) 218 ± 6 s−1 and find is approximately flat derivative...
Abstract The spectral analysis and data products in Data Release 16 (DR16; 2019 December) from the high-resolution near-infrared Apache Point Observatory Galactic Evolution Experiment (APOGEE)-2/Sloan Digital Sky Survey (SDSS)-IV survey are described. Compared to previous APOGEE release (DR14; 2017 July), DR16 includes about 200,000 new stellar spectra, of which 100,000 a southern instrument mounted on 2.5 m du Pont telescope at Las Campanas Chile. all taken up 2018 August, including...
The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has built the largest moderately high-resolution (R=22, 500) spectroscopic map of stars across Milky Way, and including dust-obscured areas. APOGEE Stellar Parameter Chemical Abundances Pipeline (ASPCAP) is software developed for automated analysis these spectra. ASPCAP determines atmospheric parameters chemical abundances from observed spectra by comparing to libraries theoretical spectra, using chi-2 minimization in a...
Very high-quality spectra of 24 metal-poor halo dwarfs and subgiants have been acquired with ESO's VLT/UVES for the purpose determining Li isotopic abundances. The derived 1D, non-LTE 7Li abundances from LiI 670.8nm line reveal a pronounced dependence on metallicity but negligible scatter around this trend. good agreement is found between 610.4nm line. estimated primordial abundance $7Li/H = 1.1-1.5 x 10^-10, which factor three to four lower than predicted standard Big Bang nucleosynthesis...
The SDSS-III/APOGEE survey operated from 2011-2014 using the APOGEE spectrograph, which collects high-resolution (R~22,500), near-IR (1.51-1.70 microns) spectra with a multiplexing (300 fiber-fed objects) capability. We describe data products that are publicly available, include catalogs radial velocity, stellar parameters, and 15 elemental abundances for over 150,000 stars, as well more than 500,000 these quantities derived. Calibration relations parameters (Teff, log g, [M/H], [alpha/M])...
Abstract The data and analysis methodology used for the SDSS/APOGEE Data Releases 13 14 are described, highlighting differences from DR12 presented in Holtzman et al. Some improvement handling of telluric absorption persistence is demonstrated. derivation calibration stellar parameters, chemical abundances, respective uncertainties along with ranges over which was performed. known issues public related to effective temperatures (DR13), surface gravity (DR13 DR14), C N abundances dwarfs DR14)...
The Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a high-resolution infrared spectroscopic survey spanning all environments (i.e., bulge, disk, and halo), with the principal goal of constraining dynamical chemical evolution models Milky Way. APOGEE takes advantage reduced effects extinction at wavelengths to observe inner Galaxy bulge an unprecedented level detail. survey's broad spatial wavelength coverage enables users data address numerous structure stellar...
Abstract APOGEE-2 is a high-resolution, near-infrared spectroscopic survey observing ∼3 × 10 5 stars across the entire sky. It successor to APOGEE and part of Sloan Digital Sky Survey IV (SDSS-IV). expanding on APOGEE’s goals addressing critical questions stellar astrophysics, populations, Galactic chemodynamical evolution using (1) an enhanced set target types (2) second spectrograph at Las Campanas Observatory in Chile. targeting red giant branch clump stars, RR Lyrae, low-mass dwarf young...
We present the first APOKASC catalog of spectroscopic and asteroseismic properties 1916 red giants observed in Kepler fields. The parameters provided from Apache Point Observatory Galactic Evolution Experiment project are complemented with surface gravities, masses, radii, mean densities determined by members Asteroseismology Science Consortium. assess both random systematic sources error include a discussion sample selection for Total uncertainties main order 80 K Teff , 0.06 dex [M/H],...
We employ the first two years of data from near-infrared, high-resolution SDSS-III/APOGEE spectroscopic survey to investigate distribution metallicity and α-element abundances stars over a large part Milky Way disk. Using sample ≈10, 000 kinematically unbiased red-clump with ∼5% distance accuracy as tracers, [α/Fe] versus [Fe/H] this exhibits bimodality in at intermediate metallicities, −0.9 < <−0.2, but higher metallicities ([Fe/H] ∼+0.2) sequences smoothly merge. effects APOGEE selection...
Formation of globular clusters (GCs), the Galactic bulge, or galaxy bulges in general, are important unsolved problems astronomy. Homogeneous infrared observations large samples stars belonging to GCs and bulge field one best ways study these problems. We report discovery by APOGEE a population inner Galaxy with abundances N, C, Al that typically found GC stars. The newly discovered have high [N/Fe], which is correlated [Al/Fe] anti-correlated [C/Fe]. They homogeneously distributed across,...
ABSTRACT We report evidence from APOGEE for the presence of a new metal-poor stellar structure located within ∼4 kpc Galactic Centre. Characterized by chemical composition resembling those low-mass satellites Milky Way, this inner Galaxy (IGS) seems to be chemically and dynamically detached more metal-rich populations in Galaxy. conjecture that is associated with an accretion event likely occurred early life Way. Comparing mean elemental abundances predictions cosmological numerical...
Abstract The updated H -band spectral-line list (from λ 15000–17000) adopted by the Apache Point Observatory Galactic Evolution Experiment (APOGEE) for SDSS-IV Data Release 16 (DR16) is presented in this work. APOGEE line a combination of atomic and molecular lines, with data drawn from laboratory, theoretical, astrophysical sources. Oscillator strengths damping constants are adjusted using high signal-to-noise, high-resolution spectra Sun, α Boo (Arcturus), as “standard stars.” Updates to...
Galactic haloes in a $\Lambda$-CDM universe are predicted to host today swarm of debris resulting from cannibalised dwarf galaxies. The chemo-dynamical information recorded their stellar populations helps elucidate nature, constraining the assembly history Galaxy. Using data APOGEE and \textit{Gaia}, we examine chemical properties various halo substructures, considering elements that sample nucleosynthetic pathways. systems studied Heracles, \textit{Gaia}-Enceladus/Sausage (GES), Helmi...
view Abstract Citations (369) References (110) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Chemical Composition of Red Giants. III. Further CNO Isotopic and s-Process Abundances in Thermally Pulsing Asymptotic Giant Branch Stars Smith, Verne V. ; Lambert, David L. Near-IR IR spectra are analyzed to obtain elemental isotopic C, N, O abundance, iron peak abundances, heavy element s-process abundances for a sample M, MS, S giants. compositions the M...
We present the results of s-process nucleosynthesis calculations for asymptotic giant branch (AGB) stars different metallicities and initial stellar masses (1.5 3 M☉), we comparisons them with observational constraints from high-resolution spectroscopy evolved over a wide metallicity range. The computations were based on previously published evolutionary models that account third dredge-up phenomenon occurring late AGB. Neutron production is driven by 13C(α, n)16O reaction during interpulse...
We present a chemical composition analysis of 36 giants in the nearby mildy metal-poor ( = -1.18) "CN-bimodal" globular cluster M4. Confronted with that has large and variable interstellar extinction across face, we combined traditional spectroscopic abundance methods modifications to line-depth ratio techniques determine atmospheric parameters our stars. derive total-to-selective 3.4 an average reddening 0.33 which is significantly lower than estimated by using dust maps made Schlegel et...
We present abundances for 22 chemical elements in 10 red giant members of the massive Galactic globular cluster ω Centauri. The spectra are relatively high spectral resolution and signal-to-noise. Using these plus published literature values, abundance trends defined as a function standard metallicity indicator iron. lowest stars Cen have [Fe/H] ∼ -1.8, initial distribution is established at this metallicity. span range -1.8 to -0.8. At metallicity, heavy-element found be well characterized...
Context. The evolution of the Milky Way bulge and its relationship with other Galactic populations is still poorly understood. has been suggested to be either a merger-driven classical or product dynamical instability inner disk.
Context. The Apache Point Observatory Galactic Evolution Experiment (APOGEE) features the first multi-object high-resolution fiber spectrograph in near-infrared ever built, thus making survey unique its capabilities: APOGEE is able to peer through dust that obscures stars disc and bulge optical wavelength range. Here we explore data included as part of Sloan Digital Sky Survey's 10th release (SDSS DR10).
view Abstract Citations (205) References (64) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Chemical Composition of Red Giants. II. Helium Burning and the s-Process in MS S Stars Smith, Verne V. ; Lambert, David L. Carbon, nitrogen, oxygen, Fe-peak, heavy s-process elemental abundances have been determined for an additional 12 stars type M, MS, or S. When combined with results obtained previously nine M K5 giant α Tau, are available 22 cool red giants....
We present the $H$-band spectral line lists adopted by Apache Point Observatory Galactic Evolution Experiment (APOGEE). The APOGEE comprise astrophysical, theoretical, and laboratory sources from literature, as well newly evaluated astrophysical oscillator strengths damping parameters. discuss construction of list, which is one critical inputs for Stellar Parameters Chemical Abundances Pipeline, three different versions that have been used at various stages project. methodology calculated...