The Relativistic Iron Emission Line - QPO Connection in GRS 1915+105

In accreting black hole and neutron star binaries, QPOs and broad Fe emissionlines are both thought to be incisive diagnostics of the inner disk, and caneven be used to constrain black hole spin parameters. We have discovered aconnection between Fe line strength and QPO phase in RXTE observations of GRS1915+105. This connection clearly ties Fe lines to radii less than 100 Rschw,where relativistic skewing is inevitable. Moreover, for a known mass, theconnection gives two measures of radius; overconstraining radii in this waywill enable mapping of the inner disk and strong tests of accretion flow modelsand general relativistic effects. We request a 45 ksec TOO observation of GRS1915+105 to study this connection at CCD resolution. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]