Galactic black hole transients show many interesting phenomena during outburst decays .
We present simultaneous X-ray ( RXTE , Swift , and INTEGRAL ) , and optical/near-infrared ( O/NIR ) observations ( SMARTS ) of the X-ray transient XTE J1752 - 223 during its outburst decay in 2010 .
The multiwavelength observations over 150 days in 2010 cover the transition from soft to hard spectral state .
We discuss the evolution of radio emission is with respect to the O/NIR light curve which shows several flares .
One of those flares is bright and long , starting about 60 days after the transition in X-ray timing properties .
During this flare , the radio spectral index becomes harder .
Other smaller flares occur along with the X-ray timing transition , and also right after the detection of the radio core .
We discuss the significances of these flares .
Furthermore , using the simultaneous broadband X-ray spectra including INTEGRAL , we find that a high energy cut-off with a folding energy near 250 keV is necessary around the time that the compact jet is forming .
The broad band spectrum can be fitted equally well with a Comptonization model .
In addition , using photoelectric absorption edges in the XMM-Newton RGS X-ray spectra and the extinction of red clump giants in the direction of the source , we find a lower limit on the distance of > 5 kpc .