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		| Paper: | 
		Variations of the Radio Synchrotron Spectral Index in M 33 | 
	 
	
		| Volume: | 
		396, Formation and Evolution of Galaxy Disks | 
	 
	
		| Page: | 
		87 | 
	 
	
		| Authors: | 
		Tabatabaei, F.S.; Beck, R.; Krügel, E.; Krause, M.; Berkhuijsen, E.M.; Gordon, K.D.; Menten, K.M. | 
	 
	
	
		| Abstract: | 
		We determine the variation in the nonthermal radio spectral index in the nearby spiral galaxy M 33. We separate the thermal and nonthermal components of the radio continuum emission without the assumption of a constant nonthermal spectral index. Using the Spitzer FIR data at 70 and 160 μm and a standard dust model, we de-redden the Hα emission. The extinction-corrected Hα emission serves as a template for the thermal free-free radio emission. Subtracting from the observed 3.6 and 20 cm emission (Effelsberg and the VLA) this free-free emission, we obtain maps of the nonthermal intensity and spectral index. | 
	 
	
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