SIMBAD references

2012ApJ...761...97M - Astrophys. J., 761, 97 (2012/December-3)

The star formation in radio survey: GBT 33 GHz observations of nearby galaxy nuclei and extranuclear star-forming regions.

MURPHY E.J., BREMSETH J., MASON B.S., CONDON J.J., SCHINNERER E., ANIANO G., ARMUS L., HELOU G., TURNER J.L. and JARRETT T.H.

Abstract (from CDS):

We present 33 GHz photometry of 103 galaxy nuclei and extranuclear star-forming complexes taken with the Green Bank Telescope as part of the Star Formation in Radio Survey. Among the sources without evidence for an active galactic nucleus, and also having lower frequency radio data, we find a median thermal fraction at 33 GHz of ~76% with a dispersion of ~24%. For all sources resolved on scales ≲ 0.5 kpc, the thermal fraction is even larger, being ≳ 90%. This suggests that the rest-frame 33 GHz emission provides a sensitive measure of the ionizing photon rate from young star-forming regions, thus making it a robust star formation rate (SFR) indicator. Taking the 33 GHz SFRs as a reference, we investigate other empirical calibrations relying on different combinations of warm 24 µm dust, total infrared (IR; 8-1000 µm), Hα line, and far-UV continuum emission. The recipes derived here generally agree with others found in the literature, albeit with a large dispersion that most likely stems from a combination of effects. Comparing the 33 GHz to total IR flux ratios as a function of the radio spectral index, measured between 1.7 and 33 GHz, we find that the ratio increases as the radio spectral index flattens which does not appear to be a distance effect. Consequently, the ratio of non-thermal to total IR emission appears relatively constant, suggesting only moderate variations in the cosmic-ray electron injection spectrum and ratio of synchrotron to total cooling processes among star-forming complexes. Assuming that this trend solely arises from an increase in the thermal fraction sets a maximum on the scatter of the non-thermal spectral indices among the star-forming regions of σαNT ≲ 0.13.

Abstract Copyright:

Journal keyword(s): cosmic rays - galaxies: nuclei - H II regions - radio continuum: general - stars: formation

VizieR on-line data: <Available at CDS (J/ApJ/761/97): table1.dat table2.dat table3.dat table4.dat table6.dat table7.dat>

Nomenclature: Table 2: [MBM2012] NGCNNNN Enuc. NN N=57

Status at CDS : All or part of tables of objects could be ingested in SIMBAD with priority 2.

Simbad objects: 48

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2012ApJ...761...97M and select 'bookmark this link' or equivalent in the popup menu


2021.07.24-16:58:39

© Université de Strasbourg/CNRS

    • Contact