THE ABUNDANCE PATTERN IN THE HOT ISM OF NGC 4472: INSIGHTS AND ANOMALIES

Journal Article · Thu Jun 10 04:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/716/1/384· OSTI ID:21450856

Loewenstein, Michael ^[1]

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1. Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)

Important clues to the chemical and dynamical history of elliptical galaxies are encoded in the abundances of heavy elements in the X-ray emitting plasma. We derive the hot interstellar medium abundance pattern in inner (0-2.3 R{sub e}) and outer (2.3-4.6R{sub e}) regions of NGC 4472 from analysis of Suzaku spectra, supported by analysis of co-spatial XMM-Newton spectra. The low background and relatively sharp spectral resolution of the Suzaku X-ray Imaging Spectrometer detectors, combined with the high luminosity and temperature in NGC 4472, enable us to derive a particularly extensive abundance pattern that encompasses O, Ne, Mg, Al, Si, S, Ar, Ca, Fe, and Ni in both regions. We apply simple chemical evolution models to these data and conclude that the abundances are best explained by a combination of {alpha}-element enhanced stellar mass loss and direct injection of Type Ia supernova (SNIa) ejecta. We thus confirm the inference, based on optical data, that the stars in elliptical galaxies have supersolar [{alpha}/Fe] ratios, but find that that the present-day SNIa rate is {approx}4-6 times lower than the standard value. We find SNIa yield sets that reproduce Ca and Ar, or Ni, but not all three simultaneously. The low abundance of O relative to Ne and Mg implies that standard core collapse nucleosynthesis models overproduce O by {approx}2.

• OSTI ID: 21450856
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 716; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABUNDANCE
ELECTROMAGNETIC RADIATION
EVOLUTION
GALACTIC EVOLUTION
GALAXIES
IONIZING RADIATIONS
LUMINOSITY
MEASURING INSTRUMENTS
NUCLEOSYNTHESIS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PLASMA
RADIATIONS
SPECTROMETERS
STARS
SYNTHESIS
X RADIATION