ENTRY            22867   20050221                             21722286700000001 
SUBENT        22867001   20050221                             21722286700100001 
BIB                 13         46                                 2286700100002 
TITLE      .s-process branching at 185W revised.                  2286700100003 
AUTHOR     (P.MOHR,T.SHIZUMA,H.UEDA,S.GOKO,A.MAKINAGA,K.Y.HARA,   2286700100004 
           T.HAYAKAWA,Y.-W.LUI,H.OHGAKI,H.UTSUNOMIYA)             2286700100005 
INSTITUTE  (2GERTHD,2JPNJAE,2JPNKON,1USATAM,2JPNKTO,2JPNJPN)      2286700100006 
REFERENCE  (J,PR/C,69,032801,2004)                                2286700100007 
FACILITY   (ESTRG,2JPNAIS) Electron  storage  ring TERAS at AIST  2286700100008 
            (Tsukuba, Japan).                                     2286700100009 
INC-SOURCE (MPH,LASER) Tunable  monochromatic photon source from  2286700100010 
            laser Compton scattering - Laser Compton  Scattering  2286700100011 
            photons, LCS.                                         2286700100012 
DETECTOR   (HE3SP) Improved neutron  detector  consisted  of  16  2286700100013 
            individual  3He  counters embedded in two rings in a  2286700100014 
            poliethilene moderator.                               2286700100015 
METHOD     (RINGR) Direct measurement of photoneutrons using the  2286700100016 
            ring-ratio  method:  ring-ratio  between  the  count  2286700100017 
            rates  of the inner and outer detector rings depends  2286700100018 
            on the neutron energy,  and hence  cfn  be  used  to  2286700100019 
            estimate the neutron energy. That varied between 2.5  2286700100020 
            and 4.4 leading to average neutron energies of about  2286700100021 
            1.2  MeV at highest photon energies and of about 0.3  2286700100022 
            MeV at lower photon energies.                         2286700100023 
SAMPLE     The target  consisted  of  1246  mg metallic tungsten  2286700100024 
            powder highly enriched in 186W to 99.79 % The powder  2286700100025 
            was pressed to a small self-supporting tablet with a  2286700100026 
            diameter of 8 mm.                                     2286700100027 
ANALYSIS   (UNFLD) For  estimation of the reaction cross section  2286700100028 
            from the experimental reaction yield  the  unfolding  2286700100029 
            procedure using the replacement of integral eguation  2286700100030 
            by Taylor series (because the difference (low-energy  2286700100031 
            tail)  of  realistic  photon  spectrum from ideal is  2286700100032 
            relatively small) was used.                           2286700100033 
ERR-ANALYS Statistical errors.                                    2286700100034 
COMMENT    The neutron capture cross  section  of  the  unstable  2286700100035 
            s-process  branching  nucleus  185W has been derived  2286700100036 
            from  experimental  data  of  inverse  186W(g,n)185W  2286700100037 
            photodisintegration  taken with monochromatic photon  2286700100038 
            beams from laser Compton scattering.  The result  of  2286700100039 
            SIG  =  553  (60)  mb  at  kT  =  30  keV leads to a  2286700100040 
            relatively high effective  neutron  density  in  the  2286700100041 
            classical  s-process  of Nn = 4.7 x 10**8 sm**-3.  A  2286700100042 
            realistic  model  for  the  s-process  in  thermally  2286700100043 
            pulsing  asymptotic giant branch stars overestimates  2286700100044 
            the abundance of 186Os significantly because of  the  2286700100045 
            relatively  small  neutron  capture cross section of  2286700100046 
            185W.                                                 2286700100047 
HISTORY    (20050118C)  V.V./S.M.                                 2286700100048 
ENDBIB              46          0                                 2286700100049 
NOCOMMON             0          0                                 2286700100050 
ENDSUBENT           49          0                                 2286700199999 
SUBENT        22867002   20050221                             21722286700200001 
BIB                  3          4                                 2286700200002 
REACTION   (74-W-185(N,G)74-W-186,,SIG,,MXW)                      2286700200003 
INC-SPECT  .Quasi-maxwellian energy spectrum                      2286700200004 
STATUS     (CURVE) The data from Fig. 3  have been digitized  at  2286700200005 
            the Russia MSU SINP CDFE by V.V.Varlamov.             2286700200006 
ENDBIB               4          0                                 2286700200007 
NOCOMMON             0          0                                 2286700200008 
DATA                 3          1                                 2286700200009 
KT         DATA       ERR-S                                       2286700200010 
KEV        MB         MB                                          2286700200011 
    30.      553.        60.                                      2286700200012 
ENDDATA              3          0                                 2286700200013 
ENDSUBENT           12          0                                 2286700299999 
ENDENTRY             2          0                                 2286799999999