We present an analysis of the first high-resolution spectra measured from an accretion-driven millisecond X-ray pulsar in outburst .
We observed XTE J1751–305 with XMM-Newton on 2002 April 7 for approximately 35 ks .
Using a simple absorbed blackbody plus power-law model , we measure an unabsorbed flux of 6.6 \pm 0.1 \times 10 ^ { -10 } ~ { } { erg } ~ { } { cm } ^ { -2 } ~ { } { s } ^ { -1 } ( 0.5–10.0 keV ) .
A hard power-law component ( \Gamma = 1.44 \pm 0.01 ) contributes 83 % of the unabsorbed flux in the 0.5–10.0 keV band , but a blackbody component ( kT = 1.05 \pm 0.01 keV ) is required .
We find no clear evidence for narrow or broad emission or absorption lines in the time-averaged spectra , and the sensitivity of this observation has allowed us to set constraining upper-limits on the strength of important features .
The lack of line features is at odds with spectra measured from some other X-ray binaries which share some similarities with XTE J1751–305 .
We discuss the implications of these findings on the accretion flow geometry in XTE J1751–305 .