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تسجيل مستخدم جديدBroadband X-ray spectral analysis of the Seyfert 1 galaxy GRS 1734-292
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We discuss the broadband X-ray spectrum of GRS 1734-292 obtained from non-simultaneous XMM-Newton and NuSTAR observations, performed in 2009 and 2014, respectively. GRS1734-292 is a Seyfert 1 galaxy, located near the Galactic plane at $z=0.0214$. The NuSTAR spectrum ($3-80$ keV) is dominated by a primary power-law continuum with $Gamma=1.65 pm 0.05$ and a high-energy cutoff $E_c=53^{+11}_{-8}$ keV, one of the lowest measured by NuSTAR in a Seyfert galaxy. Comptonization models show a temperature of the coronal plasma of $kT_e=11.9^{+1.2}_{-0.9}$ keV and an optical depth, assuming a slab geometry, $tau=2.98^{+0.16}_{-0.19}$ or a similar temperature and $tau=6.7^{+0.3}_{-0.4}$ assuming a spherical geometry. The 2009 XMM-Newton spectrum is well described by a flatter intrinsic continuum ($Gamma=1.47^{+0.07}_{-0.03}$) and one absorption line due to Fetextsc{XXV} K$alpha$ produced by a warm absorber. Both data sets show a modest iron K$alpha$ emission line at $6.4$ keV and the associated Compton reflection, due to reprocessing from neutral circumnuclear material.
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