We present results of an extensive investigation of the physical changes taking place in the emission regions of the LMXB X 1624-490 during strong flaring in observations made using RXTE in 1997 and 1999 .
Based on the detailed light curve , we propose that the flaring consists of a superposition of X-ray bursts .
It is shown that major changes take place in the blackbody emission component , the temperature kT _ { BB } increasing to \sim 2.2 keV in flaring .
Remarkably , the blackbody area decreases by a factor of \sim 5 in flaring .
During flare evolution , the blackbody luminosity remains approximately constant , constituting a previously unknown Eddington limiting effect which we propose is due to radiation pressure of the blackbody as kT _ { BB } increases affecting the inner disk or accretion flow resulting in a decreased emitting area on the star .
We argue that the large decrease in area can not be explained in terms of modification of the blackbody spectrum by electron scattering in the atmosphere of the neutron star .
The height of the emitting region on the non-flaring neutron star is shown to agree with the height of the inner radiatively-supported accretion disk as found for sources in the ASCA survey of LMXB of Church & Bałucińska-Church ( 2001 ) .
The decrease in height during flaring is discussed in terms of possible models , including radial accretion flow onto the stellar surface and the theory of accretion flow spreading on the neutron star surface of Inogamov & Sunyaev ( 1999 ) .
We demonstrate that the intensity of the broad iron line at 6.4 keV is strongly correlated with the luminosity of the blackbody emission from the neutron star , and discuss the probable origin of this line in the ADC .
Finally , possible reasons for non-detection of a reflection component in this source , and LMXB in general , are discussed .