4 X-ray Spectral Analysis

We performed our X-ray spectral analysis in several steps to ensure consistent and optimal results. We assessed in §3.1 whether the spectra can be reasonably co-added. To model the continuum, we used a phenomenological model consisting of an accretion disk model (soft band), a power-law model (hard band), and photoelectric absorption models (§4.1). For the absorption and emissions lines, we measure their properties first with Gaussian emission (§4.2) and absorption functions (§4.3) superimposed on the continuum. The analysis conducted in this section is intended as an additional measure to ensure that our reported results are robust to both simple (this section), and complex (§5) analysis techniques.

Table 2: Best-fit Parameters for the Continuum Model and Fe Lines.

Component	Parameter	Value
	$\chi^{2}/{\rm d.o.f}$ &dotfill#dotfill;	$739/659$
tbnew	$N_{\rm H}$(cm$^{-2}$ ) &dotfill#dotfill;	$2.32^{+0.48}_{-0.55} \times 10^{21}$
highecut	$E_{c}$(keV) &dotfill#dotfill;	$4.55^{+1.16}_{-2.01}$
	$E_{f}$(keV) &dotfill#dotfill;	$13.47^{}_{-10.85}$
diskbb	$T_{\rm in}$(keV) &dotfill#dotfill;	$0.064^{+0.004}_{-0.003}$
	$R_{\rm in}$(pc) &dotfill#dotfill;	$15.96^{+16.80}_{-8.25} \times 10^{-4}$
zpowerlw	$\Gamma$ &dotfill#dotfill;	$1.77^{+0.04}_{-0.19}$
	$F$(ergcm$^{-2}$s$^{-1}$) &dotfill#dotfill;	$5.45^{+0.12}_{-0.07} \times 10^{-12}$
zgauss $_{\rm K\alpha}$	$E$(keV) &dotfill#dotfill;	$6.41$
(FeK$\alpha$)	$\sigma$(keV) &dotfill#dotfill;	$0.04$
	$F$(ergcm$^{-2}$s$^{-1}$) &dotfill#dotfill;	$3.35^{+2.31}_{-2.03}\times10^{-14}$
zgauss $_{\rm He\alpha}$	$E$(keV) &dotfill#dotfill;	$6.67$
(FeXXV)	$\sigma$(keV) &dotfill#dotfill;	$0.06$
	$F$(ergcm$^{-2}$s$^{-1}$) &dotfill#dotfill;	$4.87^{+3.27}_{-2.74}\times10^{-14}$
zgauss $_{\rm Ly\alpha}$	$E$(keV) &dotfill#dotfill;	$6.96$
(FeXXVI)	$\sigma$(keV) &dotfill#dotfill;	$0.06$
	$F$(ergcm$^{-2}$s$^{-1}$) &dotfill#dotfill;	$1.67^{+2.97}_{}\times10^{-14}$

Table: X-ray Absorption Lines in PG1211+143 identified with Gaussian absorption functions (gabs )

Line	$E_{\rm lab}$	$\lambda_{\rm lab}$	$E_{\rm rest}$	$\lambda_{\rm rest}$	$v_{\rm out}$	$W_{\lambda}$	$v_{\rm turb}$	$\log N_{j}$
	(keV)	(Å)	(keV)	(Å)	(km s$^{-1}$)	(mÅ)	(km s$^{-1}$)	(cm$^{-2}$)
NeX Ly$\alpha$	1.022	12.132	1.081	11.469	$-16750^{+180}_{-630}$	$41.0 \pm 6.9$	$280^{+460}_{-190}$	$17.4^{+0.1}_{-0.1}$
NeIX He$\alpha$	0.923	13.433	0.976	12.703	$-16660^{+1290}_{-360}$	$7.5\pm 6.6$	$260^{+640}_{-190}$	$15.8^{+0.3}_{-0.9}$
MgXII Ly$\alpha$	1.473	8.417	1.557	7.963	$-16670^{+630}_{-600}$	$20.9 \pm 12.0$	$1150^{+1040}_{-870}$	$17.4^{+0.2}_{-0.4}$
MgXI He$\alpha$	1.354	9.157	1.433	8.652	$-17070^{+450}_{-180}$	$1.7\pm 1.4$	$85^{+1230}_{-70}$	$15.5^{+0.3}_{-0.7}$
SiXIV Ly$\alpha$	2.006	6.181	2.128	5.826	$-17690^{+180}_{-30}$	$1.1 \pm 1.0$	$80^{+930}_{-60}$	$16.4^{+0.3}_{-1.4}$
SiXIII He$\alpha$	1.867	6.641	1.973	6.284	$-16550^{+90}_{-570}$	$11.5\pm 6.5$	$800^{+540}_{-780}$	$17.3^{+0.2}_{-0.4}$