The evolution of normal galaxy X-ray emission through cosmic history: constraints from the 6 Ms Chandra deep field-south

Journal Article · Fri Jul 01 04:00:00 EDT 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/825/1/7· OSTI ID:22868950

Lehmer, B. D. ^[1]; Basu-Zych, A. R.; Hornschemeier, A. E. ^[2]; Mineo, S.; Gilfanov, M. ^[3]; Brandt, W. N.; Luo, B.; Schneider, D. P.; Trump, J. R. ^[4]; Eufrasio, R. T.; Yukita, M. ^[5]; Fragos, T. ^[6]; Xue, Y. Q.; Wang, J. -X. ^[7]; Bauer, F. E. ^[8]; Ranalli, P. ^[9]; Shemmer, O. ^[10]; Tozzi, P. ^[11]; Vignali, C. ^[12]; Zezas, A. ^[13]

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1. Department of Physics, University of Arkansas, 226 Physics Building, 835 West Dickson Street, Fayetteville, AR 72701 (United States)
2. NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States)
3. Max Planck Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany)
4. Department of Astronomy and Astrophysics and Institute for Gravitation and the Cosmos, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States)
5. The Johns Hopkins University, Homewood Campus, Baltimore, MD 21218 (United States)
6. Geneva Observatory, Geneva University, Chemin des Maillettes 51, 1290 Sauverny (Switzerland)
7. CAS Key Laboratory for Researches in Galaxies and Cosmology, Center for Astrophysics, Department of Astronomy, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, Anhui 230026 (China)
8. Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile)
9. Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing (IAASARS), National Observatory of Athens, 15236 Penteli (Greece)
10. Department of Physics, University of North Texas, Denton, TX 76203 (United States)
11. INAF—Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125, Florence (Italy)
12. Universitá di Bologna, Via Ranzani 1, Bologna (Italy)
13. Physics Department, University of Crete, Heraklion (Greece)

We present measurements of the evolution of normal-galaxy X-ray emission from z ≈ 0–7 using local galaxies and galaxy samples in the ≈6 Ms Chandra Deep Field-South (CDF-S) survey. The majority of the CDF-S galaxies are observed at rest-frame energies above 2 keV, where the emission is expected to be dominated by X-ray binary (XRB) populations; however, hot gas is expected to provide small contributions to the observed-frame ≲1 keV emission at z ≲ 1. We show that a single scaling relation between X-ray luminosity (L{sub X}) and star-formation rate (SFR) literature, is insufficient for characterizing the average X-ray emission at all redshifts. We establish that scaling relations involving not only SFR, but also stellar mass (M{sub ⋆}) and redshift, provide significantly improved characterizations of the average X-ray emission from normal galaxy populations at z ≈ 0–7. We further provide the first empirical constraints on the redshift evolution of X-ray emission from both low-mass XRB (LMXB) and high-mass XRB (HMXB) populations and their scalings with M{sub ⋆} and SFR, respectively. We find L{sub 2−10keV}(LMXB)/M{sub ⋆}∝(1+z){sup 2−3} and L{sub 2−10keV}(HMXB)/SFR ∝ (1+z), and show that these relations are consistent with XRB population-synthesis model predictions, which attribute the increase in LMXB and HMXB scaling relations with redshift as being due to declining host galaxy stellar ages and metallicities, respectively. We discuss how emission from XRBs could provide an important source of heating to the intergalactic medium in the early universe, exceeding that of active galactic nuclei.

• OSTI ID: 22868950
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 825; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
EMISSION
FORECASTING
GALACTIC EVOLUTION
GALAXY NUCLEI
KEV RANGE 01-10
LUMINOSITY
METALLICITY
MILKY WAY
RED SHIFT
SCALING
STARS
SYNTHESIS
UNIVERSE
X RADIATION
X-RAY GALAXIES