===============================================================================================
    
 
     ps_id_vs_tdc  ----------------> PST ID vs. TDC, Raw TDC

     ps_id_vs_tdc_calib -----------> PST ID vs. TDC (calib), Raw TDC, single T-counter trigger

     ps_id_vs_t    ----------------> PSHIT ID vs. t (ns), with already applied TDC offsets

     ps_fid_vs_bid_in_time --------> PS front ID vs. back ID.
	
     ps_id_vs_adc  ----------------> PSA ID vs. ADC, Raw ADC

     ps_fb_time_diff --------------> PS front back time difference (ns)

     ps_lf_rf_time_diff -----------> PS left-front right-front time difference (ns)

     ps_lb_rb_time_diff -----------> PS left-back right-back time difference (ns)

     psr_time ---------------------> PS reconstracted event time (ns)



============================================================================================

    calib_macro.C

          will be used to calibrate Pair Spectrometer paddles
  
            root [0].L calib_macro.C

            root [1]calib_macro("ps_id_vs_tdc_calib", 32);     

           or
  
            root [0] .x calib_macro.C("ps_id_vs_tdc_calib", 32);



     !!!! Make sure that histograms are already attached.


    in principle calib_macro.C can be used to get TDC offsets for any subsystem

           root [0] .x calib_macro.C("2d_hist", n_detector);

	   where 2d_hist is the name of 2D-histogram (detector id vs. tdc) and
                 n_detector is the integer number of detectors u want to get TDC offsets for