ENTRY C3067 20250506 C306700000001 SUBENT C3067001 20250506 20251001 C306700100001 BIB 12 56 C306700100002 TITLE Measuring the cross section of the 15N(alpha,gamma)19F C306700100003 reaction using a single-fluid bubble chamber C306700100004 AUTHOR (D.Neto,K.Bailey,J.F.Benesch,B.Cade,B.Digiovine, C306700100005 A.Freyberger,J.M.Grames,A.Hofler,R.J.Holt,R.Kazimi, C306700100006 D.Meekins,M.McCaughan,D.Moser,T.O'Connor,M.Poelker, C306700100007 K.E.Rehm,S.Riordan,R.Suleiman,R.Talwar,C.Ugalde) C306700100008 REFERENCE (J,PR/C,107,035801,2023) C306700100009 #doi:10.1103/PhysRevC.107.035801 C306700100010 INSTITUTE (1USAANL,1USACBF,1USACAL) C306700100011 (1USAUSA) Department of Physics, University of IllinoisC306700100012 at Chicago, Chicago, Illinois 60607, USA C306700100013 FACILITY (LINAC,1USACBF) The electron accelerator at Thomas C306700100014 Jefferson National Accelerator Facility. C306700100015 INC-SOURCE (BRST) The bremsstrahlung gamma-ray beam was produced C306700100016 by impinging an electron beam accelerated on a copper C306700100017 radiator (6.0 mm thick, enough to completely stop a C306700100018 10 MeV/c electron beam). C306700100019 DETECTOR (BUBLC) The C3F8 filled glass vessel. C306700100020 METHOD In a series of experiments the photodisintegration C306700100021 reaction 19F(gamma,alpha)15N was studied. If gamma C306700100022 rays from the bremsstrahlung beam interact with the C306700100023 fluorine via the 19F(gamma,alpha) 15N reaction, the C306700100024 15N and alpha particles in the outgoing channel are C306700100025 stopped in the C3F8 liquid, which leads to the C306700100026 formation of a bubble in the superheated C3F8. If a C306700100027 bubble is observed by the camera, ten consecutive C306700100028 frames taken at 10 ms intervals are stored in the C306700100029 computer providing information about the location and C306700100030 the motion of the bubble in the fluid. C306700100031 ANALYSIS (DTBAL) The method employs the advantages of detailed C306700100032 balance (time-reversal symmetry) using a thick C306700100033 (1-10 g/cm2) liquid target and a gamma-ray beam. C306700100034 Since 19F is a mono-isotopic element, no background C306700100035 reactions from the photodisintegration of other C306700100036 isotopes can occur. Due to the fact that in the C306700100037 15N(alpha,gamma) 19F reaction excited states in 19F C306700100038 are populated as well, no direct comparison between C306700100039 the measured radiative capture and photodissociation C306700100040 yields can be made. However, sufficient information C306700100041 about energies, widths, and branching ratios of the C306700100042 critical states in 19F is available to calculate the C306700100043 expected yields for the 19F(gamma,alpha) 15N C306700100044 reaction. Filling in equation for this reaction gives C306700100045 the time-reversal factor as C306700100046 sigma(gamma,alpha)/sigma(alpha,gamma) = C306700100047 mu*c**2*Ecm/Egamma*2, where mu is a reduced mass of C306700100048 the 15N and alpha particle, c speed pf light, Ecm C306700100049 center-of-mass energy of the 15N and alpha-particle C306700100050 system, and Egamma the energy of the resulting gamma C306700100051 ray. C306700100052 MISC-COL (MISC) Time-reversal factor from (alpha,gamma) to C306700100053 (gamma,alpha). C306700100054 ERR-ANALYS (DATA-ERR) Symmetric 1 sigma uncertainties. C306700100055 (ERR-1,,3.) The chamber efficiency from the C306700100056 temperature and pressure is less than 3%. C306700100057 HISTORY (20250506C) BP C306700100058 ENDBIB 56 0 C306700100059 NOCOMMON 0 0 C306700100060 ENDSUBENT 59 0 C306700199999 SUBENT C3067002 20250506 20251001 C306700200001 BIB 2 2 C306700200002 REACTION (7-N-15(A,G)9-F-19,,SIG) C306700200003 STATUS (TABLE,,D.Neto+,J,PR/C,107,035801,2023) Table - III C306700200004 ENDBIB 2 0 C306700200005 NOCOMMON 0 0 C306700200006 DATA 5 7 C306700200007 EN EN-RSL DATA DATA-ERR MISC C306700200008 MEV MEV B B NO-DIM C306700200009 4.755 0.014 1.5E-10 1.4E-10 96.5 C306700200010 4.845 0.014 9.0E-10 8.6E-10 104.2 C306700200011 4.945 0.014 1.1E-09 1.0E-09 112.1 C306700200012 5.035 0.014 3.1E-09 2.6E-09 118.5 C306700200013 5.135 0.014 3.9E-09 1.9E-09 125.1 C306700200014 5.345 0.015 3.6E-06 0.8E-06 137.1 C306700200015 5.345 0.015 1.3E-05 0.5E-05 137.1 C306700200016 ENDDATA 9 0 C306700200017 ENDSUBENT 16 0 C306700299999 ENDENTRY 2 0 C306799999999