The Photoproduction of Neutral Pions from Hydrogen

Citation

Oakley, David Charles (1955) The Photoproduction of Neutral Pions from Hydrogen. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/2HG5-JB37. https://resolver.caltech.edu/CaltechETD:etd-01132004-105847

Abstract

NOTE: Tect or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. The photoproduction of neutral pions from hydrogen has been studied by counting the recoil protons with a magnetic spectrometer and scintillation counters. The process was studied between photon energies of 260 and 450 MEV and between center of mass pion angles of 70[degrees] and 153[degrees]. The excitation functions show a resonance type shape with maxima at about 320 MEV. Angular distributions are approximately [...] plus a small constant between zero and one third. There is indication of little asymmetry in the angular distributions. The maximum cross section at 90[degrees] in the center of mass is [...]/steradian for 320 MEV photons. The total cross section divided by the square of the center of mass photon wave length has a maximum at 340 MEV. This quantity drops by about a factor of two at 450 MEV. These results are consistent with magnetic dipole and electric quadrupole absorption leading to a resonant state of the pion-nucleon system of angular momentum j = 3/2 and isotopic spin T = 3/2.

Item Type:	Thesis (Dissertation (Ph.D.))
Subject Keywords:	(Physics and Mathematics)
Degree Grantor:	California Institute of Technology
Division:	Physics, Mathematics and Astronomy
Major Option:	Physics
Minor Option:	Mathematics
Thesis Availability:	Public (worldwide access)
Research Advisor(s):	Walker, Robert Lee
Thesis Committee:	Unknown, Unknown
Defense Date:	1 January 1955
Record Number:	CaltechETD:etd-01132004-105847
Persistent URL:	https://resolver.caltech.edu/CaltechETD:etd-01132004-105847
DOI:	10.7907/2HG5-JB37
Default Usage Policy:	No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:	150
Collection:	CaltechTHESIS
Deposited By:	Imported from ETD-db
Deposited On:	14 Jan 2004
Last Modified:	06 Jul 2023 19:47

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THE PHCTOPROLDUCTION OF NEUTRAL PIONS FRCM RYDRCGEN Thesis by David Charles Oakley In Partial Fulfillment of the Requirements Doctor of Philosophy California Institute of Technology Se The he author Wishes to thenk Dr. R. L. Walker, who has been loful during the course of the experiment and during the The other members of the synchrotron group have also been most heloful and the author wishes to acknowle especially the contributions of Dr. R. FP. Bacher, Or. A. V. Dollestrun, Dr. J. C. Keek, Dr. R. V. Lenemuir, Or. i. L. or, 7. Gs bre Ve. 4. Peterson, chief engineer Bruce Rule, and sraduate students J. I. Vette, ae Bloch and P. L. Donoho. The finaneial support of the U. 5S. atomic Energy Commission is gratefully acknowledged. neutral pions from hydrogen has 9¢en studied by counting the recoil prctons with a magnetic ers. The process was wa ig ‘D or W Q a ck D 8 iy Co ta cp tote 3 et jets it 7 6% ct yale 7°) m oO o G studied between photon energiss of £60 and en center of mass pion angles of 70° and 155°. The excitation functions show a resonance type shape with maxima at about 3 a es he 2% 2 2 * ine Angular distributions are aneroximate sin ot plus a small constant between zero and one third. cation of little asymmetry in the maximum cross section at 99° in the center of mass is 2.56 x divided 4 square the : wave Length has a maximum at Ft ae ny cs lin, pets Pa 7 ey £ aye mAdace fb Ginole and sisetric quadrupole absorption Leading te a state of the olon-nucleon system cf angular momentum j = 3/2 and + ‘eh ao & Toe -_ isotopic spin T= 3/2. PART II Tit vI VII VITI aI TABLE OF CONTENTS TITLE Introduction Theory Apparatus Electronics Experimental Details Data Reduction Excitation Functions Angular Distribution Errors Comparison with Other Works Conclusions References Figures Tables PAGE 10 12 14 21 23 25 31 35 60 -L INTSCDUCTICN The photoproduction of neutral picns from hydrogen igs one of the fundamental experiments to determine the nature of the meson-proton seattering and chotoproduction of pions from hydrogen. This work reports experimental work done at the S falifornia Institute of Technology's synchrotron on the photo- oreduction of neutral pions from hydrogen. This reaction has shown (1, 2, 3, 4, 5) a marked difference from the positive pion vhotoproduction near threshold. The Of “a positive production inereases about as (Hy, - Bal”, where Ty is the gamma ray energy and H., is the threshold of the peac etion. . . a a bthreasheld and at 300 MEV is reble with the positive production. igak coupling theory oredicts that neutral production shovld be much smeller than positive production. The energy dependence and nearly isotropic angular distribution of the positive pion photo- procuetion near threshold indicates a large S state contribution to the cross section. The energy dependence and non-is sotropic angular distribution of neutral pion photonroduetion near threshold incicates very little S state contribution snd the Large Cross section near 500 MIV is suggestive of a resonance in the P state contribution. Sinee strong coupling theory predicted 2 resonance, in pion-preton scattering, of the Ps /e state with isotopic spin, n th Sa ‘eed sa ‘ ” i st oO Pa) ° @ o al Q 42 Far > =) cd ©) oO xt nd a 4 Bs) wo ai 4 os 0 > ot v3 met ~ u oO £. wey as S S fH ord o arf 43 ae) 2 at Rw) ON fon) i) ws 3 + » rs) a aed D as ot 4° 4 fa) ¢ © - s G4 a ey ® ‘dj orf ® a Gag GS Ss Oo . es wat a ® > any ie) ct > a + 3 =| -P ag co) iy] 45 fad a rea ie ® re Fan a a o oO Q s ri ce] a £9 at orl ~ o ay ® nm ap 42 42 o S eI vt 5 > wy 42> ord = = n 3 ® im) a ce] ag re © Qo — oO aD wo ~ ee) 4 3 0 Q_ S & Ps ee Oy ny ue} ri 4 cd 3 io) ci ag ae) is) n a cS 3] ce ord aed By res ca us Gost fa a | by o Qu - a & i 8] ~ gy Oo res ® ce) YQ cs o Ree] is x oO 3 Fa QO rs “3 ua) fH i oO Foss re" fa 3 by % ra ot - a) . fan ao & mm oi csi e: @ i 1 qi ey 49 rs o3 q $2 bec} oS o ae ct Qa a 4 ~~ Q a Pp Pp PP 4 ey gD fm » + o oO ie) a oO co) my) ° a o ® ® o 5 an tl * hi Bi fee p> Sd od ae - i) cf a fe) oO Q © > G GB: a] ® oO Hi gS Q ey a OG SS os} 4 ced i Pe) Gi Q el a= n oO aed aw x @ oo oom — —~ — £y rd cn 3 Q cd £4 i 2 89 st @ 1 6 oO wn £ 5 @ Fa) o a eo ed a ae aa ia o re i at i Gy a ny & ad Pe aes ed 9 3 i f4 BY i) ort al “ 3 - o 2 20 Fa hy fi) ae ad a > ay 4 78 i> sod Cott he athe me, i 10 tos £ 5) oy chmidt-Clermont, Osbeme as @ pecoil protons by , fi t pean used by Gol ;ed Le who ecun IF ) ( jg @ a a ~i ap i ®o OW i S-4 @ 4 ord es ce) ¢ pe Cad 42 ae a el yy a - EE rt +3 3) te? to fs wt Oo s ow i) cy iy Py Dy a 2 a 43 SA ot g aad « ie) sg. a ci rm = 4 Q oO (e] ie a ioe a * be 1s) oH o Ni © ag o oO oe Q ek er ek rl o Pa A st hoe 2 mb «§& @& @& oO cf sd ond + 45 « cl aed gm mM cb MO sH ra re) 42 aes a bp “ri ek a sa oy ” OQ oi tt 3 cot crs fa) ae ved a re) rea) ond Q : Oo iV) fe bea) — a ww ie} ee o Q a! ~ ard mH ae) & S . bed x} be) a] tes Si ry wo 4 3 Gy 2 =r + + + ’ £4 en 42 13 rot act be) C2 rt rot _ n ct Qo Lie & g .¢) ia 3) as ® rs ras) oO 4 > a) Jo O° to at] oO aed Ot Ol UN Fed a oO ope a e ras te me SS ~ 7 > a ® a oO ig oy j rl N ~ Y 7 IC Ss a a be ~ A Om om A fe oye 9 a3 x h gi = ca) —_ Fe D “7 fa Oo ca] os sy aR ra] w ~~ O & ry +2 ot ® ort % mn ce} 7) aX OL ped a 42 3) ao} = a > + 0 fo) S orl O a a Fy a oO Re ca) j fa 80 42 @ qn > > © ot oO ie) ne] od re] ct ap o Py ct > Fe or se Py § a aa rg Q 4 ot oc a 2 OQ ia a ae) © D . sd faa a Me un Sy gy ad ® e@ ~~ na oe ne mM i ss o oO + on) a wo (es) E 42 © Oo - Pa srl a ad ag o ra) Q + ~ Oo Sy cea ae Spent pe) ei & + Fae! °o ot Gi ie) fe] & cd p> $ a fa eet ag . uy wy fee 43 42 0 ri 4 ord S rc b= ae] S 3 Q @ ® 8 SH 03 ° oD , a fal ® . my 2 is) = o ° ' ia 42 sj a 4 Q 6 3 42 G cel Ss) Q a oi 2 co Fa 4 a as veel 42 + & ie a BS cy) & a S$ ont ai a 4 9] ® Oy o S| Ry 4 ee 9 ire] i oe q a Py 4 “y i C Bi gy | wd rs a fe) 4 o i) * ® * : e ish) 2 By 3 o 2 aie} qo 42 cd a tr 4 Py 3 a @ " @ ao Ce) is) * ei ¢ " : “ Q rod o a Nay o p ao 4 3 «4 Hi a 38 3B +5 ee 3 Es ad &4 ot ie) bi Py 4 2 & saa BY fe] ~~ £ ry fed, L 1b +3 LG + jie On “ab i g ad, B tf. ache & ut et, b a r 4 GO cs D bion ne b tr “7! i] Q my ® cc 43 SH a OF 7 2 S a tee See. qj an d i ariet — Ws art 3 Mr ‘A, a Be =, Ww C if Pao C x, i _ wi 5 4 on € cS Ca te) ay 3 aa 3 AG L0OnS 4 nn OSL way a on um J aur) Home ar whe Sos soin Or me cd E+ a @ cs sey ot VLOS ¢ Vix ve al 3) en bas b ea from hydro OT e 2 nr ¢ G. » ANG. ouron + Le, oe, ams SYTLG es S v L ciments i 4 Je PLOT otopro= it tral a Si G4 eur ay heo pe + wy =O Pay 29 hold 1 cyt OU 1 fy a DLORS eubral ¢ 2h on of ti G Co was through ¢ ane 4 ae zontal o hori a Vv e nomentum b u Fx ctron iP Ih ft VILGS wD ve the fy vont collimator. dlamet ers The hydrogen tanzet consiste ed of a stainless steel f of nominal thickness 0,030", 2 in diameter end 17" Lone, enclosed in © blocks of styrafoam insulation 6" high by 5° wide, and most of the time further enclosed in a dowble polyethylene baz of O.OLL" total thickness tc keep water from condensing on the steel, 1. Attached te the flask a liquid nitrogen reservoir to cool the gas. Hydrogen was passed through a liquid nitrogen trap each time the target was filled tc remove any water vapor, The target was filled te 2000 pai, allowed to cool for about an hour with liguid. nitrogen in the reservoir, refilled $0 2000 psi and sealed off « Thereafter the liquid nitrogen reservoir was kept filled and the temperature sad pressure of the gas were measured period jee SS vl keep track of the density of the hydro eu, The temperature wes measured by means of two tren-constantin thermo: couples, one atv the CIV pale whe oa ef “, 4 SCN, the jron-coustantin calibration teble in thse Handbook of Chemistry v 1 FPyhy- faiy r Bobo mee ny m an and Physies (15). Ths density was found Ah es a3 i wn He aes 4 off me ot 7 Tower +t Same apts we FN ths trosoh 2 mm mped belo o gy 43 cS is 7 ay BD bsorb etie i wed? orn SF 3 LUCA gs, & ‘i is a u i) t abe 3 nt, Lo fs Le 3a.0k ND t rns = cancelled by the s am is © Rel Q 413 Sy o a war oon that i) a oe + Qo Bs mclLear L oa S an The aaa! ing ys he o® 43 4 @ cs) n Susi COPE é re we to 1 oulé net v i Spat 4 second, 1G V0 Niade MLCrg re ae ontectad 4 @ uk oS ¢ S © Q Ss 42 oO » ee @ i MLOrose 7 e © a fa ok, Moniter = 7 to Dp p ro c ed + a gy Ps wa ont & Y ot t 2 +£ se cd + Io wicks USO CO oS ie ee @ Oo w oO Oo cd g 5 od a £0 = Qo OQ ‘oe % U3 Gy ci o mi ty fo} im os ae) ca Be i ae A os LO a oe DS whe ae i . ‘ a Gus fas qt 2 Ra te x > oad rl e] , G Si iH Gi 8 > mt ee fs 42 oO 42 fy » — Be sed > bt a) cad ord a uh @ t 23 bee t hy for + & ; my eh me “iD 3 @ , a> ri i fy a ort co, Qs aad a a o- G s . ri f4 th cy ct hy, aad pot re » iis) S pa ® ont ei a Gt | I a HM co] 42 +) Be) ic as ne PKS LY J 20 “3 fy Oo S o c nd Si 4> coun oy “te jm Vy oh thin a Qa x 8 s + %3 PY ~~ ie) © Guat a o ica re gy ie ¢ n ba iotat 8 i py Rt AN NH) Wk) AR ca fi w a Sh ren @ a © Py Q 3) qo a us rc m ta) cf ct cs Gi ° * 6 rat a) iS a Se ed 4 © © ae K do ad s f 13 Fy ost “oS ee 4 ~ “¢ C C & “re he af POAC wi Bo P 273 Be T 8B ) = Yk: (A) Be B 273 T ] af 5 para + u per AIG lLSePs wns 5 rat Met Sd ack ap Ore oer a a a) tH od 3 ri a BO ron Bee rj * P* TAM Pa LL cd ad for all LT Ea 97 J ore gq 4 7 4a ] " EL rotons +r a + AR*gsonsen ¢ RR(T*) WALL cm AK CER £3 { oA aL _ PS i A oO /2. Zz +t SMa TM = cov GY) E . Fr Pcov @, ~T aT M + £4; (| - — al aT ( —— A A: «9 Op - Bu ben Gr 2 go) ~? Bom a) [1 +( - 8&8 cea ? 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A table of errors will be included in part IX. i= VIII ANGULAR DIE SPRISUPIONS The pion center of mass angles ean be found from the velo~ 2 cities of the orcton and the center of mass and the angle of the proton in the laboratory system by: ~ | - Bem zen Op Tin OL = for a particular photon energy from each lsboratory angle and + os ¢ Pa ry ae SK Sm ~ L1, os , Mh 4 oe plot en anguler distribution in the center of Chis oeen dons Gna 1S snewn in LSU ah i. in table I. The center of mass aneuler of Fisure 9 With a linear ordinete. The sclid curves ere a least squeres fit to a form A t+ B coe @ + C ov? & o Ba ction of photon The walues aa hd Weck pa QS a laboratory energy are shown in figure 10. In figure 9, the 270 MEV is obtained from the intersection of (Qs © ct ok a3) cu oO fad ry rad D ry oO ry the three curves for A, B and C with 270 MEV in figure 10, showing that the curves for these parameters are not incon sistent with the three noints that were measured at this enersy. S The eneular distribution is alse fitted to a form: in figure ll. The curves are the central curves for 4 and C from figure 10. ra oe . 9 Since the data extenc only to 70° at most, the odd powers of co sO, could not be well determined in an infinite power series = fo cos). However, by restriction of the power series to at most =) i rms of second order, the first vower determines the slope of or @ u the angular distribution near 90°. If B were made as large as either A or C, one would not be able to fit the data satisfactorily. assuming the coefficients of the nower series as Was obtained by the least squares fit, the tota fete tT re w <a) oH ot raw] Qo oN fen co) bs =) Oo i or © ra) cn to ta a 1e2] bo a) © be j Cx ° yo “3 es oO 0. This eross section Givided by the scuare of the center of mass pactcon Wave length is cietted in figure 12. assigned to the points in the ex-~ citation functions include: Counting statistics and estimate of error in g the orocton peak from the pion .eak. arror due to part of the beam dumping before the gating circuit opened the counters = +0% =1%. Uncertainty in resetting the magnetic analyzer le voltages * =) + a a. Sac - those thes d not. skids MOSS Td @ Absorber thickness = +1 of thidcness. Absorber scattering md absorption= £10% of total correction. o and a oO . ny —— 5 BH Sy * od a9 ap fe) x a Q sj rot aad oh ce . 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S =| gq fa ® rey Pal ie} ga o “cl oS ww a] a] a) 0 a © fy fa Pal ~— ra, can o wm na ree] > a) icy oF wy o o fay a aged mt @ © od a se opt ei bs . © ad co) Sa oS 2 3 al qj ca) 42 cee) - ony © D us ie 3 o At Sa iS uy ad @ F @ 9 st Oo fa) © a) 43 a 2 i | Q al Fa s st Si a ed G4 ir ay G4 5) e o @ & ° ise] ct 0) oO © a rm 9 et al 4 eal ay aS 3 @ RD 4 G4 a Sa onl re} 3) E4 oS af ay P> oa oO o fa £ ae) re] 3 . aD & ted ‘¢ e © °o & . fe fa) fy i) ~ Se a a D ond § ca 2 o fy a 1] Sa fy 2 e G bs} @ Ss a ae feat G44 a) a ar D a a ca] a 4o H o cd ia @ oe) aoe) i ce) ra ba 2) ' es cd ie) o 4 & a] o 42 P 0 wc a Py ref] o a 4 ord ae aa oO bp q om Aer » o i ave ® aed ord cea oD Ry at fad) G4 iss) co & ° ro) 3 ard Se i] a gy n S a ad Sd SJ 3] a4 1 ws He 3 Fe ey rt AG] Ra o j= Go o a 3 et <4 e ot ay fy Ba = Hi SH aS Dy St g ag is) a i) ag ro o o a 4 g fa S S onl crt) cae] rf 4 m © Q nf fe) ua ae fa 42 o @ a <4 a ¢. o @ e Pa pert wy eH 2 a cee fe S & - a ee o a) ES ie » 9 H Fs wt s 5 ot sg fa ; Q. Si *_ & SG 2) ge og a - 3 o Qo cl ch cae] ort ay 4 ad Q o 3 © ont ~ cy aoe ~ (i) te) G4 FS od 4 Pp Pb ww By is) oa Q 1) a fe) ed o mee ed vot co] od a © me = + a a ap 2 A g q re) g Q ve B cy fo) ; = ce} 3 om ~ ie o © + +3 © ~ < rah) rot ro} os rd wt Fe © & 4 a oO o Q rl a i) Boag sq fa a qui ret a 4a Eve] ff) o e fen] rs} Fa @ i} wi + as 3g ¢ Ss = oo a Co) o MH ceed “ot ond oo on] ot) fa n an a a a) Q gq 3 re a) is] fa od re) Qy oa} 2; o ree a ro BV] 4 td ed fe Q [2 ® ca] as i @ © ep P rm 4 ; wi sf . a fa) aod Sy 8 SS ey £4 ot » <f @ tot ira] & as o & Y A Pad ad a @ ie) | . o ay a a oS mo = o 6 - my o oO a fe) Ps wn 4 AY cl © fl @ a Ra) ft ay Sy ocd M tw ie ae) = ao) 3 as 3 19 we ie) + 0 - ®% O © 4 Qo @ Q ocd ce) as) a me att 43 ne) fe) SH qi ae 9° ad » aeto on ot the ae i 1. =. F Le erved, i as obs no a 4 & $4 @ aan SO UIE ¢ VO VOI. can Erol io Ee © wi ae is) i L na 2 f y/ els are on yen 27 Ook by te fig we on R g 4a ot o @ & o a ert on RBethets —~ Ss ~ iva we “SN N ® mr 2) "27, dele to eB Cr ba ition OU a] a ob remy eed 8 O51 ome) @ * £ « 4 e $ at iy he ee temo ih <H S rd a qd 7 he @ ' 4 oD py ~“ ro « Le Oo rd iy at oo) ts moO ” yl fy tH KD aes Ki A] ® —~ eel ° uD uy on & ba re tp oH o a oot 2 an rd _ Fi = oa te) O — iH uy a re con G4 me fd ie i a @ ei . e oi or) a D © o ri ang £3 — Po rN = 45 oe $ bs GS cj a an S f >, ta i 5 5 gf " Boog at ¢ — + e a o iA) © of} 2 ® a n a 2 5 es “> ; a a Pe o & 5 2 BS} aa cp (2) Si & 4 i. x pam 3 oS a: ° e 3 rae oD Co 4 e o e e ~~ one _— co roi n © LQ a i Ca rd rm ed rf rf ed ee od aed — ~~ ee senee FR we GC. 3. Bakker and Phys. Rev. As Aaron, University of California Radiation Labora (19) Report (22) T. B. Taylor ys. Rev. 92 831 L (1953) | Bruno Rossi a3 tn Energy Particles” (1952) 344 De H. Cooper, Thesis, California Institute of Technolo — ra) Ie eae (1955) i G. Keck (private communication, see synehrotren we an =: cy ° laboratery nebebook #853) (27) Geoffrey F. Chew (28) 39 H. A. Bethe and F. de Hoffman (preprint of letter to ap pear in the Physical Review ) 1 Old 1334 — 5 wv3aa G ¢ € 2@ 1 O aa ivwinn0) SYOLY TTILNIOS avn NOLLVINSNI —— 390-1 a90NWL 7H SYNLY3adY M SxOA LANSVW YAN IdILINWOLOHd NMOHS LON MW0D LANSVW YOLINOW YSEWVHD NOI 41 SCINTILLATORS PHOTOMULTIPLIERS RCA TYPE 5819 PREAMPLIFIER MOD.25 DWG1IOT-157 PULSE AMPLIFIERS -— x MOD.522A DWGIOT-163L7! 2 . FAST COUNTER im + FAST COUNTER MOD. 11 | 2 owe. 1or.74]# | COINCIDENCE CIRCUIT Fp MOD.IO00 DWG.10T-129 ¢ DOUBLE[_ # COINC. OUT %| + DOUBLE ~SCALER|MON || BR [cowc.cat Mon’ SCALER OWG IOT-19 4 a | #, +, 1+"2I CONG. INTEGRAL BIAS DISCRIMINATOR MON. | DOUBLE 4 uae SCALER A 2 DELAYED! AGG. MON B EACH 3 Cc DOUBLE SCALER DOUBLE D DWG 10-T-101 SCALER E FIG. 2 F BLOCK DIAGRAM OF ELECTRONIC APPARATUS G H 42 13 12 AP NO COINCIDENCE Pp COINCIDENCE 10 \ 09 aN APERTURES ve e° 192 12 32. 2 08 40 45 50 55 X (INCHES FROM VERTEX OF MAGNETIC FIELD ) FIG.3 RELATIVE RANGE OF MOMENTA ACCEPTED BY COUNTERS WITH LONG FOCUS ia T oo j | - eee - fee = ; H i i i i i } i 7 i i ! } i 3 ‘ i : id a 1 : 1 | Cone enn near _ § j § i { i | ! i r ' --4 Lo} @ sect 1 ane wee ee i ¢ 9 BA 31 California Institute daly ay rs i pe fo nec fm fe mare mns = ols, ineide: 1 i oft 3 i é iia. Ingtitute yo \ i tothe : i wept I a facies : f + 1 ne oe i | H i : ern arnen| t 7 { pe eee dd i L - wep nce bee ne feeb ht aha L eee ee ee ee ee ! pet Be Sec Bh ag te ne aera, i t » i i ifs angle, { 4. “4 titate ‘of ‘of mass differential . cross tory. 4 whe he 6 i t ae - fine. i - 4 A. ; Pood “+ for proton ‘a bod i i t ‘ 7 { i a A No epines: oe bee nS Dee { i da a f i te hnology ‘of Tee 1954 uate on ae ‘ A ? : different t otion lab fornia Thstit Cali 1 wee Hb t 1 whee ~ ore i i 1 vty “on foterad a . E i bee Ay Cina i : : : : i ! ee ee ae i ; i ‘ ; | Leet { je section t t ; t bros i i ang -aton laboratory. aR aNOry — t ifornia Inst for pro Gal em epee eb : i itute of Technol fl j te t \ dg i “Tt | Q ent /steradin cd alee i { a “eg tne @ent Pro Ag 3.0 in T 4; =320 MEV 295 7 sca ww a 270 oOo A 4008 OS™ = 1.0F 4 5 = § = | 4903-——z e FE oN ™~N «a O.6F ? 4 = QO S 6 ANGULAR DISTRIBUTIONS } — FOR VARIOUS PHOTON ENERGIES : bie THE CURVES ARE: |S 0.3h , » al | Wy A+Bcos Onm+ Ccos* Or 0.2 . 4 ANGULAR RESOLUTION (LINEAR SCALE) IAAL Ai 6 fe) 100 120 140 160 On PION CENTER OF MASS ANGLE FIG. 9 ————Ewo7oO~ (AaW) ADYAN3S G@V1 NOLOHd LNZGION! 7¥ 00s OSb - 00b os¢ 00¢ oSz 002 OSI T T 7 } q T 1 1 QTOHSSYHL Vv ™ | oo 2 af UG 2099+ LG 6099+V IN : ptt P WuOd AG vouerasio iz 72 Se YVINONY OL Lid S3YVNOS I vad r LSV31_ NI SIN3IOIZ435090 VoL qe G3ZIIVWYON ‘“LIW ae NVIGVYSLS / ND 620! Ol Old r it — ih i t b (ASN) ADNSN3S @V1 NOLOHd LNAGIONI 73 00S OSp OOb ose oo¢ ose 002 Osi ; i O1'914 WONS NANVL k 9 aNv v S3ANND ¥ X f 4 y- ¥ ) GTOHS3SYHL 50 ‘o) NVIGVUALS /2N9 ™20! ae J ae #9 2809 ItV NN a 12 WHO4 AG NOILNGIYLSIC YVINONY OL Lid SSYVNOS i 1SV31 NI SLN3IO144300 I} Olds 4. de L be i i L nie bv 51 ' 2 C/(Xy) 04} O2t 1 Ol + a] 300 350 400 450 A; INCIDENT PHOTON LAB ENERGY (MEV) FIG. l2 Ft 52 FIG. 13 CROSS SECTIONS MEASURED 3, BY cC, Af, Cu AND P& ABSORBERS BEFORE SCATTERING CORRECTIONS Op = lat” 2 | L. S t i 1 i ae | CS 390 400 410 420 430 4 \NCIDENT PHOTON LAB ENERGY (MEV) Lid > —- CARBON ABSORBERS | aed < © ALUMINUM ABSORBER Wd 0D COPPER ABSORBER A LEAD ABSORBER 6Fr 5 4- I j i 1 360 380 400 420 440 hi INCIDENT PHOTON LAB ENERGY (MEV) 53 Y+P—-p+1° EFFECT OF SCATTERING FROM LEAD SHIELDING LAB. PROTON ANGLE @ p= 19.5° 3 | dg- (10729 cm2 ) dn STERADIAN FIG.14 4-NO COINCIDENCE $ - COINCIDENCE OPEN FIGURES—BRIDGES CLOSE TO PROTON BEAM SOLID FIGURES~BRIDGES 8 AWAY FROM PROTON BEAM 250 300 350 400 450 500 Bi (MEV) 54 4 O+P—=p 47° EFFECT OF SCATTERING FROM LEAD SHIELDING LAB. PROTON ANGLE 4, = 29° 3 a (107° cM’/STERADIAN ) FIG. 15 5 A-NO COINCIDENCE 7” s é ¢- COINCIDENCE > ; 5 OPEN FIGURES —BRIDGES | 5 é CLOSE TO PROTON BEAM SOLID FIGURES — BRIDGES a¢ & AWAY FROM PROTON BEAM 4 4 é 4 5 é é (J fo) 250 300 350 400 450 500 Ri (MEV) 55 fe (10°? °cm?/STERADIAN) y+p—pt+tT EFFECT OF SCATTERING FROM LEAD SHIELDING LAB. PROTON ANGLE ©, = 40.5" 4-NO COINCIDENCE t . ? 3 - COINCIDENCE Hh OPEN FIGURES~ BRIDGES i 4° 5 CLOSE TO PROTON BEAM ts § 3 SOLID FIGURES ~ BRIDGES 4 § AWAY FROM PROTON BEAM 3 FIG.I6 $ ; - 250 300 350 400 450 500 i ( MEV ) 5% te, ( 10° cM?/STERADIAN ) FIG.17 T | S+P—-pt+1 EFFECT OF SCATTERING FROM LEAD SHIELDING , LAB. PROTON ANGLE © = 50} r i A-No COINCIDENCE $- COINCIDENCE OPEN FIGURES— BRIDGES 7—+ CLOSE TO PROTON BEAM SOLID FIGURES— BRIDGES AWAY FROM PROTON BEAM : 4 2 ¢ i 250 300 350 400 450 500 Ri (MEV) a7 INVESTIGATION OF PROTON COMPTON EFFECT CONCLUSION: 9 7 (AAR) 5 wey * 0.025+0,025) 0 (%P;P, 47) 355 MEV N“N Lj DD T 7+ Pe P+? —— 1+P Psy’ o T $ q [o-+ MEV CORRECTED TO P =.0300 GRKC H, - L- a 3 60 ANGULAR wo RESOLUTION we 30° 40° , 50° 6 Ss oO Oo FIG.18 | 3 9 ENERGY RESOLUTION 4 re) jo rn | 250 300 350 400 450 500 SYNCHROTRON PEAK ENERGY (MEV) RELATIVE Oy nN 58 CHECK OF Y+P--P +/Y° BY LOOKING AT Y+P-—-Pism° ABOVE AVAILABLE Y ENERGY (500 MEV) | ASSUMING 1(4;) CO Zz re Bi O5- ©, = 192 RESOLUTION O aN | | 45 500 550 4, \NCIDENT PHOTON ENERGY (MEV) 1.o- b . FIG.I9 \ oe RESOLUTION sl 0 450 500 550 4; \NCIDENT PHOTON ENERGY (MEV) 59 (AJN) AOYS3N3 GV1 NOLOHd LN3GION! 7% 00S OSb 00b ose oo¢ osz — 002 Osi T T " 1 if { qT T T A3W OSb ONV oor | \ 5 (, dav 10dvuLx3 JE RN SL4IHS 3SWHd $,3HL39 * x oO S1sIHS 3SVHd aoe 5} x OQ7OHS3YHL ; oo x ANOZHL NOS3W 440 LN SM3HO O¢2 Old i 4. i —T NVIGVYSLS /,WO .20! Lab, Angle Energy de qn 270 Or d¢ an 295 / On da dv 320 / On da 3600 Or dg, 400 * Or Ge se’ 450 12 1/2° 81+ 13 153 1,234.12 153 1,09+ ,08 153 0 72t ,06 153 336+ 04 153 221+ 04 153 60 TABLE I 19 1/2° 1,05%,06 136 1,55+,06 137 1.73 06 137 1,29+ ,06 138 «76+ 04 138 138 29° 1,51+ 05 114 2.12+ 05 115 2.33% 06 115 1.78% 06 116 1,094 .05 117 644 03, 117 _ ANGULAR DISTRIBUTION OF Y+ P—» P + rr° 40 1/2° 2.244 09 89 2,56+.08 90 2,204.06 91 1,414 05 92 078+ 05 — 93 Gf, is in units of 10°°7em*/steradian 50 1/4° 1,82t.15 70 1,36+ 06 71 oS1+ 04 72 61 TABLE IT j = 3/2, T = 3/2 PHASE SHIFTS TO FIT A T (MEV) ie, (MEV) of 33 (Chew) 6 45(Bethe) S33 (Ross) 125 270 Al 34 60 150 295 61 51 72 175 320 77 72 nr:Y) 215 360 95 106 110 255 400 113 116 129 305 450 130 132 142 Jd 33 (Ross) and the last two of the other 4 *s were chosen to fit A