Description:
<jats:title>ABSTRACT</jats:title>
<jats:p>We report on the X-ray spectral behavior within the steady states of GRS1915+105. Our work is based on the full data set of the source obtained using the Proportional Counter Array (PCA) on the <jats:italic>Rossi X-ray Timing Explorer</jats:italic> (<jats:italic>RXTE</jats:italic>) and 15 GHz radio data obtained using the Ryle Telescope. The steady observations within the X-ray data set naturally separated into two regions in the color–color diagram and we refer to these regions as steady-soft and steady-hard. GRS1915+105 displays significant curvature in the coronal component in both the soft and hard data within the <jats:italic>RXTE</jats:italic>/PCA bandpass. A majority of the steady-soft observations displays a roughly constant inner disk radius (<jats:inline-formula>
<jats:tex-math>
<?CDATA ${R}_{{\rm{in}}}$?>
</jats:tex-math>
<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apj523116ieqn1.gif" xlink:type="simple" />
</jats:inline-formula>), while the steady-hard observations display an evolving disk truncation which is correlated to the mass accretion rate through the disk. The disk flux and coronal flux are strongly correlated in steady-hard observations and very weakly correlated in the steady-soft observations. Within the steady-hard observations, we observe two particular circumstances when there are correlations between the coronal X-ray flux and the radio flux with log slopes <jats:inline-formula>
<jats:tex-math>
<?CDATA $\eta \sim 0.68\pm 0.35$?>
</jats:tex-math>
<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apj523116ieqn2.gif" xlink:type="simple" />
</jats:inline-formula> and <jats:inline-formula>
<jats:tex-math>
<?CDATA $\eta \sim 1.12\pm 0.13$?>
</jats:tex-math>
<jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apj523116ieqn3.gif" xlink:type="simple" />
</jats:inline-formula>. They are consistent with the upper and lower tracks of Gallo et al. (2012), respectively. A comparison of the model parameters to the state definitions shows that almost all of the steady-soft observations match the criteria of either a thermal or steep power-law state, while a large portion of the steady-hard observations match the hard-state criteria when the disk fraction constraint is neglected.</jats:p>