We present an X-ray spectral analysis of 126 galaxies of the 12 micron galaxy sample ( 12MGS ) .
By studying this sample at X-ray wavelengths , we aim to determine the intrinsic power , continuum shape and obscuration level in these sources .
We improve upon previous works by the use of superior data in the form of higher signal to noise spectra , finer spectral resolution and a broader band pass from XMM-Newton .
We pay particular attention to Compton thick AGN with the help of new spectral fitting models that we have produced , which are based on Monte-Carlo simulations of X-ray radiative transfer , using both a spherical and torus geometry , and taking into account Compton scattering and iron fluorescence .
We use this data to show that with a torus geometry , unobscured sight lines can achieve a maximum equivalent width ( EW ) of the Fe K \alpha line of \sim 150 eV , originally shown by .
In order for this to be exceeded , the line of sight must be obscured with N _ { H } > 10 ^ { 23 } cm ^ { -2 } , as we show for one case , NGC 3690 .
We also calculate flux suppression factors from the simulated data , the main conclusion from which is that for N _ { H } \geq 10 ^ { 25 } cm ^ { -2 } , the X-ray flux is suppressed by a factor of at least 10 in all X-ray bands and at all redshifts , revealing the biases present against these extremely heavily obscured systems inherent in all X-ray surveys .
Furthermore , we confirm previous results from that show that the reflection fraction determined from slab geometries is underestimated with respect to toroidal geometries .
For the 12 micron selected galaxies , we investigate the distribution of X-ray power-law indices , finding that the mean ( < \Gamma > = 1.90 _ { -0.07 } ^ { +0.05 } and \sigma _ { \Gamma } = 0.31 _ { -0.05 } ^ { +0.05 } ) is consistent with previous works , and that the distribution of \Gamma for obscured and unobscured sources is consistent with the source populations being the same , in general support of unification schemes .
We determine a Compton thick fraction for the X-ray AGN in our sample to be 18 \pm 5 % which is higher than the hard X-ray ( > 10 keV ) selected samples .
Finally we find that the obscured fraction for our sample is a strong function of X-ray luminosity , peaking at a luminosity of \sim 10 ^ { 42 - 43 } erg s ^ { -1 } .