Today's Progress 12. June. 2007

&Sigma reconstruction/&Sigma N correlation analysis:E570

Cycle-by-cycle results for &Sigma reconstruction are obtained from the links following:

&Sigma N event statistics for E570 cycles. For the primary neutron, selection A means the neutron detection software threshold (3~5 MeVee) and 1/&beta selection (1.6-7.0~9.0) to define physical neutron. For the primary proton, it is defined by successfull energy loss correction with 'reaction vertex' and layer B hit if the proton is measured on TC. Selection B is defined by the elimination of unhealthy PB counter hit(nothing for 1st cycle, R-15 for 2nd second cycle).
YN pair(dibaryon/tribaryon channel)	case ID(Selection)	Angler acceptance	PA/PB/NT particle	TC particle	No. of reconstructed &Sigma	No. of event after A	No. of event after B (yield of &Sigma N pair with well-defined momenta)
&Sigma^-p(X⁰/S⁰)	1(C-b-1-x/A-b-3-x)	180+-30	n+p	&pi	1639/654	1581/632	1581/620
&Sigma^-p(X⁰/S⁰)	1(C-b-x-1')	90+-45	n	&pi+p	2208/1071	1620/752	1620/752
&Sigma^+-n(X⁺/S⁺)	1(C-b-3-x)	180+-30	n+n	&pi	1584/715	1017/457	1017/457
&Sigma^+-n(X⁺/S⁺)	1(C-b-x-3')	90+-45	n	&pi+n	1152/537	1152/537	1152/537
&Sigma^-p(X⁰/S⁰)	2(B-c-1-x)	90+-45	&pi+p	n	296/127	280/119	280/110
&Sigma^-p(X⁰/S⁰)	2(B-c-x-1'/B-a-x-3')	180+-45	&pi	n+p	1759/689	1535/602	1535/586
&Sigma^+-n(X⁺/S⁺)	2(B-c-3-x)	90+-45	&pi+n	n	484/168	484/168	484/164
&Sigma^+-n(X⁺/S⁺)	2(B-c-x-3')	180+-45	&pi	n+n	485/189	485/189	485/185
&Sigma^-p(X⁰/S⁰)	3(B-a-3-x)	90+-45	&pi+n	p	1063/415	723/291	723/281
&Sigma^+-n(X⁺/S⁺)	3(B-c-3-x)	90+-45	&pi+n	n	1368/517	1368/517	1368/509

The results are exhibitted below for all event topologies: