skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The SEGUE Stellar Parameter Pipeline. V. Estimation of Alpha-Element Abundance Ratios From Low-Resolution SDSS/SEGUE Stellar Spectra

Journal Article · · Astron.J.
 [1];  [1];  [2];  [3];  [3];  [4];  [5];  [6];  [7];  [8]
  1. Michigan State U.
  2. IAC, La Laguna; Laguna U., Tenerife; University Coll. London
  3. Lick Observ.
  4. Case Western Reserve U.
  5. Ohio State U.
  6. Ewha Women's U., Seoul
  7. Bangalore, Indian Inst. Astrophys.
  8. Fermilab
+ Show Author Affiliations

We present a method for the determination of [alpha/Fe] ratios from low-resolution (R = 2000) SDSS/SEGUE stellar spectra. By means of a star-by-star comparison with degraded spectra from the ELODIE spectral library and with a set of moderately high-resolution (R = 15,000) and medium-resolution (R = 6000) spectra of SDSS/SEGUE stars, we demonstrate that we are able to measure [alpha/Fe] from SDSS/SEGUE spectra (with S/N > 20/1) to a precision of better than 0.1 dex, for stars with atmospheric parameters in the range Teff = [4500, 7000] K, log g = [1.5, 5.0], and [Fe/H] = [-1.4, +0.3], over the range [alpha/Fe] = [-0.1, +0.6]. For stars with [Fe/H] < -1.4, our method requires spectra with slightly higher signal-to-noise to achieve this precision (S/N > 25/1). Over the full temperature range considered, the lowest metallicity star for which a confident estimate of [alpha/Fe] can be obtained from our approach is [Fe/H] ~ -2.5/ preliminary tests indicate that a metallicity limit as low as [Fe/H] ~ -3.0 may apply to cooler stars. As a further validation of this approach, weighted averages of [alpha/Fe] obtained for SEGUE spectra of likely member stars of Galactic globular clusters (M15, M13, and M71) and open clusters (NGC 2420, M67, and NGC 6791) exhibit good agreement with the values of [alpha/Fe] from previous studies. The results of the comparison with NGC 6791 imply that the metallicity range for the method may extend to ~ +0.5.

Research Organization:
Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), High Energy Physics (HEP)
Contributing Organization:
Sloan Digital Sky Survey
DOE Contract Number:
AC02-07CH11359
OSTI ID:
1974211
Report Number(s):
FERMILAB-PUB-10-467-AE-CD; arXiv:1010.2934; oai:inspirehep.net:873092
Journal Information:
Astron.J., Vol. 141
Country of Publication:
United States
Language:
English

References (80)

The First Data Release of the Sloan Digital Sky Survey journal October 2003
The Second Data Release of the Sloan Digital Sky Survey journal July 2004
The Third Data Release of the Sloan Digital Sky Survey journal March 2005
The Seventh data Release of the Sloan Digital sky Survey journal May 2009
The Fourth Data Release of the Sloan Digital Sky Survey
  • Adelman‐McCarthy, Jennifer K.; Agueros, Marcel A.; Allam, Sahar S.
  • The Astrophysical Journal Supplement Series, Vol. 162, Issue 1 https://doi.org/10.1086/497917
journal January 2006
The Fifth Data Release of the Sloan Digital Sky Survey
  • Adelman‐McCarthy, Jennifer K.; Agueros, Marcel A.; Allam, Sahar S.
  • The Astrophysical Journal Supplement Series, Vol. 172, Issue 2 https://doi.org/10.1086/518864
journal October 2007
The Sixth Data Release of the Sloan Digital Sky Survey
  • Adelman‐McCarthy, Jennifer K.; Agüeros, Marcel A.; Allam, Sahar S.
  • The Astrophysical Journal Supplement Series, Vol. 175, Issue 2 https://doi.org/10.1086/524984
journal April 2008
A Spectroscopic Study of the Ancient Milky Way: F‐ and G‐Type Stars in the Third Data Release of the Sloan Digital Sky Survey journal January 2006
The Segue Stellar Parameter Pipeline. iii. Comparison with High-Resolution Spectroscopy of Sdss/Segue Field Stars journal October 2008
vby C a Hβ CCD Photometry of Clusters. VI. The Metal-deficient Open Cluster NGC 2420 journal January 2006
The broadening of strong lines of Ca+, Mg+ and Ba+ by collisions with neutral hydrogen atoms journal November 1998
Estimation of Stellar Metal Abundance. II. A Recalibration of the C[CLC]a[/CLC] [CSC]ii[/CSC] K Technique, and the Autocorrelation Function Method journal February 1999
A Faint New Milky Way Satellite in Bootes journal August 2006
Cats and Dogs, Hair and a Hero: A Quintet of New Milky Way Companions journal January 2007
Leo V: A Companion of a Companion of the Milky Way Galaxy? journal September 2008
Big Fish, Little Fish: two new Ultra-Faint Satellites of the Milky way journal March 2010
Elemental abundance trends in the Galactic thin and thick disks as traced by nearby F and G dwarf stars journal November 2003
$\mathsf{\alpha}$-, r -, and s -process element trends in the Galactic thin and thick disks journal March 2005
Chemical Composition in the Globular Cluster M71 from Keck HIRES Spectra of Turnoff Stars journal August 2005
Two stellar components in the halo of the Milky Way journal December 2007
Structure and Kinematics of the Stellar Halos and Thick Disks of the Milky way Based on Calibration Stars from Sloan Digital sky Survey dr7 journal March 2010
The chemical abundance of the very metal-rich old open clusters NGC 6253 and NGC 6791 journal July 2007
Na-O anticorrelation and HB: VII. The chemical composition of first and second-generation stars in 15 globular clusters from GIRAFFE spectra journal July 2009
Na-O anticorrelation and HB: VIII. Proton-capture elements and metallicities in 17 globular clusters from UVES spectra journal July 2009
Intrinsic iron spread and a new metallicity scale for globular clusters journal October 2009
Empirical calibration of the near-infrared Ca II triplet -- I. The stellar library and index definition journal September 2001
Empirical calibration of the near-infrared Ca II triplet -- II. The stellar atmospheric parameters journal September 2001
Abundances in a Large Sample of Stars in M3 and M13 journal January 2005
C and N Abundances in Stars at the Base of the Red Giant Branch in M15 journal September 2005
HIGH-RESOLUTION SPECTROSCOPY OF EXTREMELY METAL-POOR STARS IN THE LEAST EVOLVED GALAXIES: URSA MAJOR II and COMA BERENICES journal December 2009
Metallicities of Old Open Clusters journal November 2002
The Sloan Digital Sky Survey Photometric System journal April 1996
Abundances and Kinematics of Field Stars. II. Kinematics and Abundance Relationships journal January 2002
"Sculptor-ing" the Galaxy? The Chemical Compositions of Red Giants in the Sculptor Dwarf Spheroidal Galaxy journal March 2005
Standard Solar Composition journal January 1998
The Sloan Digital Sky Survey Photometric Camera journal December 1998
The 2.5 m Telescope of the Sloan Digital Sky Survey journal April 2006
Is the Sun a Sun-Like Star? journal January 1998
A 235 Star Sample Sodium, Magnesium, and Aluminum Abundance Study in the Globular Clusters M3 (NGC 5272) and M13 (NGC 6205)
  • Johnson, Christian I.; Kraft, Robert P.; Pilachowski, Catherine A.
  • Publications of the Astronomical Society of the Pacific, Vol. 117, Issue 838 https://doi.org/10.1086/497435
journal December 2005
Metallicity and Alpha‐Element Abundance Measurement in Red Giant Stars from Medium‐Resolution Spectra journal August 2008
Multi-Element Abundance Measurements from Medium-Resolution Spectra. i. the Sculptor Dwarf Spheroidal Galaxy journal October 2009
Uncovering Extremely Metal-Poor Stars in the Milky Way's Ultrafaint Dwarf Spheroidal Satellite Galaxies journal September 2008
VALD–2: Progress of the Vienna Atomic Line Data Base journal July 1999
A Unique star in the Outer halo of the Milky way journal May 2009
The Segue Stellar Parameter Pipeline. i. Description and Comparison of Individual Methods journal October 2008
The Segue Stellar Parameter Pipeline. ii. Validation with Galactic Globular and open Clusters journal October 2008
On the Typical Timescale for the Chemical Enrichment from Type Ia Supernovae in Galaxies journal September 2001
Abundance Ratios and Galactic Chemical Evolution journal September 1997
Mapping the Galactic Halo. VI. Spectroscopic Measures of Luminosity and Metallicity journal May 2003
The ELODIE Archive
  • Moultaka, J.; Ilovaisky, S. A.; Prugniel, P.
  • Publications of the Astronomical Society of the Pacific, Vol. 116, Issue 821 https://doi.org/10.1086/422177
journal July 2004
A Simplex Method for Function Minimization journal January 1965
Explosive nucleosynthesis and Type I supernovae journal April 1984
Chemical abundance analysis of the open clusters Cr 110, NGC 2099 (M 37), NGC 2420, NGC 7789, and M 67 (NGC 2682) journal February 2010
Astrometric Calibration of the Sloan Digital Sky Survey journal March 2003
Analysis of the carbon-rich very metal-poor dwarf G77–61 journal April 2005
Early performance and present status of the Hobby-Eberly Telescope conference August 1998
Element abundances of unevolved stars in the open cluster M 67 journal April 2006
Elemental abundance survey of the Galactic thick disc journal April 2006
Estimation of stellar atmospheric parameters from SDSS/SEGUE spectra journal March 2007
Abundance Patterns in the Draco, Sextans, and Ursa Minor Dwarf Spheroidal Galaxies journal February 2001
VLT/UVES Abundances in Four Nearby Dwarf Spheroidal Galaxies. I. Nucleosynthesis and Abundance Ratios journal February 2003
ESI, a New Keck Observatory Echellette Spectrograph and Imager journal August 2002
Star-To-Star Abundance Variations Among Bright Giants in the Metal-Poor Globular Cluster M15 journal November 1997
The Chemical Composition Contrast between M3 and M13 Revisited: New Abundances for 28 Giant Stars in M3 journal April 2004
Barium and Sodium Abundances in the Globular Clusters M15 and M92 journal September 2000
The Radial Velocity Experiment (RAVE): First Data Release journal September 2006
Sloan Digital Sky Survey: Early Data Release journal January 2002
Galacti chemical evolution: Hygrogen through zinc journal May 1995
Stellar lifetimes and abundance ratios in chemical evolution journal May 1979
VLT/UVES Abundances in Four Nearby Dwarf Spheroidal Galaxies. II. Implications for Understanding Galaxy Evolution journal February 2003
High-resolution fiber-coupled spectrograph of the Hobby-Eberly Telescope conference July 1998
The merging history of the Milky Way journal February 1996
Stellar Chemical Signatures and Hierarchical Galaxy Formation journal September 2004
Analysis of medium resolution spectra by automated methods – Application to M 55 andωCentauri journal May 2005
SEGUE: A SPECTROSCOPIC SURVEY OF 240,000 STARS WITH g = 14-20 journal April 2009
Elemental Abundance Ratios in Stars of the Outer Galactic Disk. I. Open Clusters journal August 2005
The Sloan Digital Sky Survey: Technical Summary journal September 2000
A Curious Milky Way Satellite in Ursa Major journal September 2006
A New Milky Way Dwarf Satellite in Canes Venatici journal May 2006
The Radial Velocity Experiment (Rave): Second data Release journal June 2008

Similar Records

THE SEGUE STELLAR PARAMETER PIPELINE. V. ESTIMATION OF ALPHA-ELEMENT ABUNDANCE RATIOS FROM LOW-RESOLUTION SDSS/SEGUE STELLAR SPECTRA
Journal Article · Tue Mar 15 00:00:00 EDT 2011 · Astronomical Journal (New York, N.Y. Online) · OSTI ID:1974211
+7 more
ELM: AN ALGORITHM TO ESTIMATE THE ALPHA ABUNDANCE FROM LOW-RESOLUTION SPECTRA
Journal Article · Wed Jan 20 00:00:00 EST 2016 · Astrophysical Journal · OSTI ID:1974211
+1 more
Globular and Open Clusters Observed by SDSS/SEGUE: the Giant Stars
Journal Article · Fri Dec 18 00:00:00 EST 2015 · The Astronomical Journal (Online) · OSTI ID:1974211
+10 more

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
79 ASTRONOMY AND ASTROPHYSICS