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Title: SCUSS u- BAND EMISSION AS A STAR-FORMATION-RATE INDICATOR

Abstract

We present and analyze the possibility of using optical u- band luminosities to estimate star-formation rates (SFRs) of galaxies based on the data from the South Galactic Cap u band Sky Survey (SCUSS), which provides a deep u -band photometric survey covering about 5000 deg{sup 2} of the South Galactic Cap. Based on two samples of normal star-forming galaxies selected by the BPT diagram, we explore the correlations between u -band, H α , and IR luminosities by combing SCUSS data with the Sloan Digital Sky Survey and Wide-field Infrared Survey Explorer ( WISE ). The attenuation-corrected u -band luminosities are tightly correlated with the Balmer decrement-corrected H α luminosities with an rms scatter of ∼0.17 dex. The IR-corrected u luminosities are derived based on the correlations between the attenuation of u- band luminosities and WISE 12 (or 22) μ m luminosities, and then calibrated with the Balmer-corrected H α luminosities. The systematic residuals of these calibrations are tested against the physical properties over the ranges covered by our sample objects. We find that the best-fitting nonlinear relations are better than the linear ones and recommended to be applied in the measurement of SFRs. The systematic deviations mainly come frommore » the pollution of old stellar population and the effect of dust extinction; therefore, a more detailed analysis is needed in future work.« less

Authors:
; ; ; ; ; ; ; ; ; ;  [1]; ;  [2];  [3]; ;  [4];  [5]
  1. Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012 (China)
  2. Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)
  3. Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China)
  4. Shanghai Astronomical Observatory, Chinese Academy of Science, 80 Nandan Road, Shanghai 200030 (China)
  5. Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China)
Publication Date:
OSTI Identifier:
22664032
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 835; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ATTENUATION; CALIBRATION; CORRELATIONS; EMISSION; GALAXIES; INFRARED SURVEYS; LUMINOSITY; NONLINEAR PROBLEMS; STAR EVOLUTION; STARS

Citation Formats

Zhou, Zhimin, Zhou, Xu, Wu, Hong, Fan, Zhou, Jiang, Zhao-Ji, Ma, Jun, Nie, Jun-Dan, Wang, Jia-Li, Wu, Zhen-Yu, Zhang, Tian-Meng, Zou, Hu, Fan, Xiao-Hui, Lesser, Michael, Jing, Yi-Peng, Li, Cheng, Shen, Shi-Yin, and Jiang, Lin-Hua, E-mail: zmzhou@bao.ac.cn. SCUSS u- BAND EMISSION AS A STAR-FORMATION-RATE INDICATOR. United States: N. p., 2017. Web. doi:10.3847/1538-4357/835/1/70.
Zhou, Zhimin, Zhou, Xu, Wu, Hong, Fan, Zhou, Jiang, Zhao-Ji, Ma, Jun, Nie, Jun-Dan, Wang, Jia-Li, Wu, Zhen-Yu, Zhang, Tian-Meng, Zou, Hu, Fan, Xiao-Hui, Lesser, Michael, Jing, Yi-Peng, Li, Cheng, Shen, Shi-Yin, & Jiang, Lin-Hua, E-mail: zmzhou@bao.ac.cn. SCUSS u- BAND EMISSION AS A STAR-FORMATION-RATE INDICATOR. United States. doi:10.3847/1538-4357/835/1/70.
Zhou, Zhimin, Zhou, Xu, Wu, Hong, Fan, Zhou, Jiang, Zhao-Ji, Ma, Jun, Nie, Jun-Dan, Wang, Jia-Li, Wu, Zhen-Yu, Zhang, Tian-Meng, Zou, Hu, Fan, Xiao-Hui, Lesser, Michael, Jing, Yi-Peng, Li, Cheng, Shen, Shi-Yin, and Jiang, Lin-Hua, E-mail: zmzhou@bao.ac.cn. Fri . "SCUSS u- BAND EMISSION AS A STAR-FORMATION-RATE INDICATOR". United States. doi:10.3847/1538-4357/835/1/70.
@article{osti_22664032,
title = {SCUSS u- BAND EMISSION AS A STAR-FORMATION-RATE INDICATOR},
author = {Zhou, Zhimin and Zhou, Xu and Wu, Hong and Fan, Zhou and Jiang, Zhao-Ji and Ma, Jun and Nie, Jun-Dan and Wang, Jia-Li and Wu, Zhen-Yu and Zhang, Tian-Meng and Zou, Hu and Fan, Xiao-Hui and Lesser, Michael and Jing, Yi-Peng and Li, Cheng and Shen, Shi-Yin and Jiang, Lin-Hua, E-mail: zmzhou@bao.ac.cn},
abstractNote = {We present and analyze the possibility of using optical u- band luminosities to estimate star-formation rates (SFRs) of galaxies based on the data from the South Galactic Cap u band Sky Survey (SCUSS), which provides a deep u -band photometric survey covering about 5000 deg{sup 2} of the South Galactic Cap. Based on two samples of normal star-forming galaxies selected by the BPT diagram, we explore the correlations between u -band, H α , and IR luminosities by combing SCUSS data with the Sloan Digital Sky Survey and Wide-field Infrared Survey Explorer ( WISE ). The attenuation-corrected u -band luminosities are tightly correlated with the Balmer decrement-corrected H α luminosities with an rms scatter of ∼0.17 dex. The IR-corrected u luminosities are derived based on the correlations between the attenuation of u- band luminosities and WISE 12 (or 22) μ m luminosities, and then calibrated with the Balmer-corrected H α luminosities. The systematic residuals of these calibrations are tested against the physical properties over the ranges covered by our sample objects. We find that the best-fitting nonlinear relations are better than the linear ones and recommended to be applied in the measurement of SFRs. The systematic deviations mainly come from the pollution of old stellar population and the effect of dust extinction; therefore, a more detailed analysis is needed in future work.},
doi = {10.3847/1538-4357/835/1/70},
journal = {Astrophysical Journal},
number = 1,
volume = 835,
place = {United States},
year = {Fri Jan 20 00:00:00 EST 2017},
month = {Fri Jan 20 00:00:00 EST 2017}
}
  • We use Spitzer 24 {mu}m, 70 {mu}m and ground-based H{alpha} data for a sample of 40 SINGS galaxies to establish a star formation rate (SFR) indicator using 70 {mu}m emission for sub-galactic ({approx}0.05-2 kpc) line-emitting regions and to investigate limits in application. A linear correlation between 70 {mu}m and SFR is found and a star formation indicator SFR(70) is proposed for line-emitting sub-galactic regions as {Sigma}(SFR)(M{sub sun} yr{sup -1} kpc{sup -2}) = 9.4 x 10{sup -44} {Sigma}(70)(erg s{sup -1} kpc{sup -2}), for regions with 12 + log(O/H) {approx}> 8.4 and {Sigma}(SFR) {approx}> 10{sup -3}(M{sub sun} yr{sup -1} kpc{sup -2}), withmore » a 1{sigma} dispersion around the calibration of {approx}0.16 dex. We also discuss the influence of metallicity on the scatter of the data. Comparing with the SFR indicator at 70 {mu}m for integrated light from galaxies, we find that there is {approx}40% excess 70 {mu}m emission in galaxies, which can be attributed to stellar populations not involved in the current star formation activity.« less
  • Polycyclic aromatic hydrocarbon (PAH) emission features dominate the mid-infrared spectra of star-forming galaxies and can be useful to calibrate star formation rates (SFRs) and diagnose ionized states of grains. However, the PAH 3.3 {mu}m feature has not been studied as much as other PAH features since it is weaker than others and resides outside of Spitzer capability. In order to detect and calibrate the 3.3 {mu}m PAH emission and investigate its potential as an SFR indicator, we carried out an AKARI mission program, AKARI mJy Unbiased Survey of Extragalactic Sources (AMUSES), and compared its sample with various literature samples. Wemore » obtained 2-5 {mu}m low-resolution spectra of 20 flux-limited galaxies with mixed spectral energy distribution classes, which yielded the detection of the 3.3 {mu}m PAH emission from 3 out of 20 galaxies. For the combined sample of AMUSES and literature samples, the 3.3 {mu}m PAH luminosities correlate with the infrared luminosities of star-forming galaxies, albeit with a large scatter (1.5 dex). The correlation appears to break down at the domain of ultraluminous infrared galaxies (ULIRGs), and the power of the 3.3 {mu}m PAH luminosity as a proxy for the infrared luminosity is hampered at log[L {sub PAH3.3} erg{sup -1} s{sup -1}] > {approx}42.0. Possible origins for this deviation in the correlation are discussed, including contributions from active galactic nuclei and strongly obscured young stellar objects, and the destruction of PAH molecules in ULIRGs.« less
  • We present, for the first time, a statistical study of [N II] 205 {mu}m line emission for a large sample of local luminous infrared galaxies using Herschel Spectral and Photometric Imaging Receiver Fourier Transform Spectrometer (SPIRE FTS) data. For our sample of galaxies, we investigate the correlation between the [N II] luminosity (L{sub [N{sub II]}}) and the total infrared luminosity (L{sub IR}), as well as the dependence of L{sub [N{sub II]}}/L{sub IR} ratio on L{sub IR}, far-infrared colors (IRAS f{sub 60}/f{sub 100}), and the [O III] 88 {mu}m to [N II] luminosity ratio. We find that L{sub [N{sub II]}} correlatesmore » almost linearly with L{sub IR} for non-active galactic nucleus galaxies (all having L{sub IR} < 10{sup 12} L{sub Sun }) in our sample, which implies that L{sub [N{sub II]}} can serve as a star formation rate tracer which is particularly useful for high-redshift galaxies that will be observed with forthcoming submillimeter spectroscopic facilities such as the Atacama Large Millimeter/submillimeter Array. Our analysis shows that the deviation from the mean L{sub [N{sub II]}}-L{sub IR} relation correlates with tracers of the ionization parameter, which suggests that the scatter in this relation is mainly due to the variations in the hardness, and/or ionization parameter, of the ambient galactic UV field among the sources in our sample.« less
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