ML20058L533

Forwards Rept from NRC Consultant Gr Odette Re Yankee Rowe Reactor Vessel Integrity.Response Requested by 900806

ML20058L533
Person / Time
Site:	Yankee Rowe
Issue date:	08/02/1990
From:	Sears P Office of Nuclear Reactor Regulation
To:	Jeffery Grant YANKEE ATOMIC ELECTRIC CO.
References
NUDOCS 9008070277
Download: ML20058L533 (17)

Text

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' Dicke t"No.- 50-029 -

August 2, 1990 e-

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'Ms. Jane M. Grant

-Senior Engineer - License Renewal-Yankee Atomic Electric Company?

580 Main Street'-

Bolton, Massachusetts 01740-1398 p

SUBJECT:

YANKEE R0WE REACTOR VESSEL INTEGRITY Enclosed for your comment is a letter received from Professor G. R. Odette, l'

an NRC consultant.

Additionally, as a result of a staff review of Section 3.4.? and 3.4.8.1 of the e

~ YNPS technical specifications, the staff would like your answers to the following i

question by COB August 6, 1990:

.1) Are the pr' essure / temperature limits in Section 3/4.4.8 of your o

tec'anical specifications being increased in accordance with p

Figures B 3/4.4-1 and B 3/4.4-2 of in the bases section?

I

2) What is the PORY pressure setting for technical specification 1

LCO 3.4.2.b?

3)Howwasthepressure. setting-andMCStemperatureoperability

requirements in technical specification LCO 3.4.2.b determined?

4) Are these settings and operability requirements being adjusted to 5"

account for neutron irradiation damage, in accordance with Figures B 3/4.4-1 and B 3/4.4-2?

Sincerely, Original signed by:

Patrick M. Sears, Project Manager Project Directorate-I-3 Division of Reactor Project - I/II-Office of Nu lear Reactor Regulation

Enclosure:

As stated h

cc w/ enclosure: T. Murley J. Russell F. Miraglia J. Partlow A.-Thadani S. Varga J. Richardson See next page 6

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Dr. Andrew C. Kadak, President-i

.and Chief;0perating Officer-

-Yankee Atomic Electric Company 580 Main Street l

1 Bolton, Massachusetts: 01740-1398 Thomas Dignan, Esquire

. Ropes and Gray 225 Franklin Stre'et

I Boston, Massachusetts.02110 i

. Mr.' T. K. Henderson

- Acting Plant Superintendent Yankee Atomic Electri_c Company Star Route Rowe, Massachusetts 01367

. Resident. Inspector -

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t Yankee' Nuclear Power-Station U.S. Nuclear' Regulatory Comission

= Post Office Box 28 Monroe Bridge, assachusetts. 01350 Regional Administrator, Region'I' U;S. Nuclear Regulatory Commission-

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475 Allendale Road

- King lof(Prussia, Pennsylvania;19406 1

Robertt M.. Hallisey, ' Director i

Radiation. Control Program I

' Massachusetts Department of Publi

..ealth 150. Tremont Street, 7th Floor

- Boston, Massachusetts '02111 i Mr. George'Sterzinger Comissioner.-

Vermont Department of Public Service

120~ State Street, 3rd Floor Montpelier, Vermont; 05602 j

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okeENoi50-029 August 2, 1990 Ms. Jane M.--Grant

-. Senior Engineer - License Renewal Yankee Atomic Electr.ic Company

=580 Main Street' Bolton, Massachusetts 01740-1398

Dear Ms. Grant:

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SUBJECT:

YANKEE R0WE REACTOR VESSEL INTEGRITY Enclosed for your comment is a letter received from Professor G. R. Odette, an NRC consultant.

Additionally, as a result of a staff review of Section 3.4 ? and 3.4.8.1 of the H

YNPS technical specifications, the staff would like your answers to the following a

question by COB August 6, 1990:

1

1) Are the pressure / temperature limits in Section 3/4.4.8 of your technical specifications being increased in accordance with Figures B 3/4.4-1 and B 3/4.4-2 of in the bases section?

2) What is the PORY pressure setting for technical specification LCO 3.4.2.b?

3) How was the pressure' setting and MCS temperature-operability-

.I requirements in technical specification LCO 3.A.2.b determined?

4) Are these settings and operability requirements being adjusted to account for neutron irradiation damage, in accordance with Figures:B 3/4.4-1 and B 3/4.4-27 Sincerely, Original signed by:

Patrick M. Sears, Project Manager Project Directorate 1-3 Division of Reactor Project - I/II Office of Nuclear Reactor Regulation

Enclosure:

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A. Thadani S. Varga J. Richardson See next page 6

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... 'm x, s w i. #-n 's n u "b6 S A N T A' 15 A }( L AL g A 4 ,?. [p + [ G. H(lill:kT Ol>t.Trs: orric.1-:of Till Inn AGttotg J Vitro of tk 5% C o#,7,* 1.//lsig n, mis tif \\ (ULLEGl: Uy EN(asy;yyggj - ? 1:Myt xsg1T op c,4:ja ogsig-5AYl A lSAHilAMg, C4 ejg)y,. J (NUS)N9.b311) LAX' (M')s) t% MIN 7/30,90 l - AlTaboada ' Division of Enginecting. US Nuclear Regulatory Couunission MS NLS217(C)- Washington., DC 20555 Dent Al, The brief report on the work you requested on the Yankee Rowe Vessel is enclosed. While I'm sure that it is far frorn the last word oli the matter, I hope it proves to be of some assistance to you. Please let me know if I can be of further assistance. Best regards, SL u O. R. Odette P vfessor of Nuclear Engineering and Engineering Materials / /') n / i tt N l' V 1: M d i T i O F (; A L i F 0 M N l A 1 s

-. A& v l 7/30/90 1990 Shift Estimates For the-Yankee Rowc Vessel G. R. Odette ' Professor of Nuclear Engineering and Engineering Materials g University of California, Santa Barbara P

1. Introductory Comments This re

' NRC)[ pen is in response to a request of the U.S. Nuclear Regulatory Commission ( estimates of reference temperature shifts expen)enced by t (YRV) as of 1990, and 2) provide my own evaluation of these shifts. This document briefly describes the results of my evaluations. In pan, due to the relatively short time available, the analysis cannot be viewed as comprehensive or definitive However,it should be clearly stated at the outset that, even give more time,it would not be possible to gdnerute rigorous or reliable shift predictions based on either what we know about the YRV itself or the existing methodology to account for the lowcr irradiation temperature (= $00 F or less). For example, there is only one valid YRV surveillance data point ($t = 0.22 l . nomhet with a N1 110 F for the upper plate); and even in this case the fluence is not I known with any cenuinty. The other (upper plate) data point, again associated with a uneenain Duence,is for a high nux/lcad factor level which disqualifies it as being a' valid surveillance data point (I also suspect that the actual irradiation temperature may also be higher in this case due to in core gamma heating). Hence, one is forced to seek other sources ofinformation. Recent progress In understanding embrittlement at higher temperatures (e.g. 550 F) Os clearly demonstrated that the phenomenon is caused by a number of interacting mechanisms l which are mediated by the combination of a number of metallugical and environmental 1 l-variables. Rigorous interpolation and extrapolation of the large surveillance data base will ultimately require validated physical models. Simpic analytical prediction procedures t~ should be viewed us an interim engineering cxpedient which usefully represent data trends

over limited variable ranges. For example,if a irradiation tempcrumre sensitivity of 1 F/F is aroposed,it should be understood that this is not a description of some fundamental schavior, but rather a representitive observation pertinent only to a well defined set of conditions.The paucity of relevant data near 500 F forces one to rely even more on such engineering rules of thumb.

' Hence this assessment, while guided by what is currently known about embrittlement L mechanisms, was based on the engineering approach described above.1 have reviewed the 'infonnation peninent to the YRV provided in the repon to the NRC by Yankee Atomic, i the draft analysis prepared by Hiser2 and other relevant information in the literature (primarily, data for arradiations at or near 500 F) cited below. Most of the Irradiation data is from accelcrated materials test reactor (MTR) experimentst hence,I have, of necessity, ignored possible effects of neutron flux. The 500 F irradiation data, encompassing a modest range of steel (base and weld) compositions, is both limited and "unscrub acd". cb &,hY. -1,9 \\h??

. j, a -+ +x ~ - In the case of the Yankee Rowe (YR) plates,1 used various approaches to try tu identify ' + "self. consistent" shift estimates. In the case of the YR welds,1 recommend use of a preliminary trend curve which may account for uncertainties both in the metallurgical-composidon of the steels and due to the lower of irradiation temperature. *lhe recommended y~ shifts are based on the 1990 vessel fluenec estimates of Hiser2,- My shift estimates may be on the conservative side of nominalin the sense that one cun-identify data which fall below the predictions. On the other hand it would be relatively easy-to propose much higher numbers, and I emphatically believe that there are many good p reasons to be prudently cautious. I

2. Comments on - Assertions in 'the Yankee Atomic Report on Grain Size Effects There are limited data in the literatti m.g. Ref 3) which support the contention that irradiation embrittlement sensitivity of s.ritic steels increases with increasing grain size.

The Yankee Atomic Report (YAR) asserts that this is related to a higher concentration of irradiation induced deIcets due to a presumed lowcr sink strength in coarse grained steels. However, this is a very unlikely mechanism since, for among other reasons, the internal defect' sink strength, due to features such as dislocations is typically many orders m-magnitude higher than the grain boundary sink strength itself". Any simple interpretation of such data trends is confounded by the complex interaction of a number of underlying embrittlement processes and the fact that, m general, several microstructural parameters vary along with grain size. However, a inuch more likely explanation of a grain size effect is related to the micromechanics of deformation and fracture: viz. - the temperature shift due to a specific irradiation induced change in microstructure which occurs on a very fine (nanometer) scale is larger in coarse ver>us fine grained steels. Indeed, the most plausible mechanism can be deduced from micron echanics models of brittle fracture: a given change in yield stress can cause larger temperature shifts in coarse versus fine grained steels 54. Yield stress changes are largely controlled by the fine scale microstructure, composition and the environmental variables (fluence, temperature, Dux and spectrum), and are not expected to be directly in0uenced by gram size. - The latter conclusion is directly supported by data shown in Figure I from a controlled, (single variabic) experiment on a smgfe heat of model A533D pressure vessel steeld. Within data scatter, the austentizing temperature variation from 900 to 1000 C, corresponding to train sizes of about 15 and 50 pm respectively, has essentially no effect on the irradiation unduced yield stress increases. Note that this and other data in reference 4 has been 4 misinterpreted in the YAR. In particular, contrary to the assertiort in the YAR, both nickel and irradiation temperature influence yleid stress changes in coarse as well as Gne grained stec!s'.' Figure 2 shows the optical micrographs for two steels which both have relatively coarse prior austenitic grain sizes (a50pm): alloy PK containa 0.41% Cu and 0.86% Ni and was austentized at 1000 C;

alloy LA contains 0.40% Cu and 0.001% Ni and was austentized at 900 C. Both steels received the same temper and stress relief treatments. Figure 3a shows the temperature dependence of yield stress increases for alloy LA at an interpolated fluence of 1.1x1019n/cm2. The observed sensitivity of 2.5 MPa/C is actually slightly larger than normal, but well within typical scatter. Yield stress changes for coarse grained LA and PK at a fluence of 0.9x1019n/cm2 and an irradiation temperature of 305 C are plotted as a function of nickel contem in Figure 3b; an essentially " typical" nickel sensitivny for these conditions of 50 MPa/Niis observed. Due to the likelihood of an increased ratio of

.me.- " n.t f expected to increase, rather than decrease,in coarse grained

3. Embrittlement Data for. Irradiations at 500 F Jn order to more directly address irradiation embrittlement at 500i10 F I carried out a literature survey which yicided shift data for a modest ran,;c of stedls (base an

rclevant" com high copper (>. position ranges (e.g. low to-intermediate nicxel (<l %) and intermed 15%))NO The data, plotted in Figure 4, are far too limited and scancred evaluate the effects of the metallur ical variables that are known to be signific temperatures (e.g. copper, nickel nd, ossibly phosphoro.M. However, the 500 F data can be effectively bounded by a Reg. Suide 1.99 Rev 2 Ouence fu with a enemistry factor (CF) of 300 F. Henec, AT = 300f,t (1) provides a seasonable preliminary 500 F trend curve. I do not helleve that it is . neccessarily (or should be considered) a bounding shift curve since the small data base i not sufficient to establish cither physically or statistically validated uncerninty limits.

4. Upper Plate Shift Estimates There may be a. valid dosimetry basis for the Cuence revisions proposed in the YAR.

There is insufficient detail presented to suppen this jud ement. However, the sugge 1 i that a comparison of YR and BR3 shift data supports a usting the Cuences and temperature effects is not clearly demonstrated by the data. Ln.In plots of the combined' YR/BR3 data set for various combinations of temperature and Ouence correction facto of 500 F based on a 1 F/F ndditive term. The closed cir 500 F using a multiplicative correction factor, Ct C =1 + 0.006(T.500) .i i (2) which yields a nominal value of 1.3 for T = $50 F. The s a upper plate data assumin the nominal and twice nomir.

• quares and triangles are the YR Puences respecuvely,if the low fluence (< 1x1019n/cm2 BR3 data are ignored, the comen.. %. t of the nominal fluences and'the Ct adjustment factor provides the best fit over the largest fluence range.

square fit of the in in data (sohd line) yicids an upper plate shift expression AT = 183$tO15 (p) (3) This gives a. shift estimate at 4: = 2.3x1019 of 238 F versus an estimate based a In.In interpolation of the nominal YR data'of 245 F. Assuming the YR fluences are twice L L nominal is more consistent with the low fluence BR3 data and a 1 d correction term. A least square fit to this data (dashed line) for $t > lx101,F/F tempera yields AT = 1740to.283 (p) (4) 7,a and a 1990 shift estimate of 220 F. ,1 l f

-. - +. ._4' Reconunendation - v Considering the vaslous uncertaintles it is not possible to ' discriminate between the v ' approaches to data correction (or manipulation). Hence. I recommend use o more conservative procedure of directly inicrpolating the nominal upper plate data to the 1990-YRV fluence.- As noted above, this gives.a nominal bhlft estimate for-the upper plate of about 245 F. 5.1,ower Pinte Shift Estimates F .The lower plate contains siightly more copper (0.2%) und significantly more nick (0.63%) than the upper plate (nominally 0.18%Cu and 0.18% Ni). Hence, shift es must account for the combination of lower irradiation temperature (nomin:dly 500 F), t Several approaches were cons (idered. higher nickel content and the ap Approach 1 One approach would be to define a composite correction factor, C nis, based on the the estimated u t 2.3x1019 /emEper plate shift of 245 F to the 110 F shift predicted by RG 1.99 Rev 218 at Reg.Ouide Rev.2 predicted shift of 181 F (for the lower plat n i W 0.63% Ni at 1.05x1019 n/cm2) by Cuil, = 2.23 yields a total shift estimate of 404 F..'this considerably exceeds the estimate from h'q 1 of about 360 F, hence, seems to Conservative. Approach 2 An additive correction term based on the difference between the estimate Rev. 2 predicted upper plate shift (245-110 = 135 F) combined with the RG 1.99 Rev. 2 prediction for the lowerplate yields a total shift estimate of 316 F. Approach 3 ' Since the primary difference between the upper and lower plate is the nickel concentrati would seem useful to look for other sources of information to estimate th i embrittlement associated with a difference'of 0.45% (0.63%-0.18%)in nicke i a) Refe.*vnce 12 shows the yield stress increase due to irradiation varies with nickel cont as Acys = A + UNI (5) where the nickcl coefficient D is a function of temperature, Guence (and, possibly, c neutron flux and heat treatment). A slight extra >olation of the data given in Figure 13 of - reference 12 to 500 F yicids a value of B = 150 MPa/%Ni for a fluence of about 1.5x1019 'n/cm2. The mab'nitude of B would be ex,)ected to inercase at higher fluence of the lower plate (2.05x10 n/cm2) to about 175 M?a/%Ni. A nominal average shift to yield stress change ratio, AT/oop, is about 1 F/MPa (note, this may be higher for coarse grained steels). Hence, a difference in nickel content of 0.45% corresponds to a shift difference of '19 F.

,A>; i. b) The shifts predicted by Reg. Guide 1.99 Rev 21I for for the u . plate (181 F) compositions and respective 1990 fluences differ bhper (110 F) vers 71 F. ' arising from: i) copper rich precipitates and 2) so call 4 copper contribution is believed to be relatively tem erature insensitive while the ma p o contribution: increases 'with increasing nickel [.1215 and. decreasing irradi h temperaturc 3,1215. Equation 22 of reference 13 can be med to estimate th a increase of 0.45% nickel on the matrix contribution at 500 F and 2.05x j K evaluation yicids a increment of 99 F; note this may be somewhat high since E temperature sensitivity assumed in E 1 - observed in the range of 500 to 550 F (quation 22 of reference 13 is larger than no typically, about 1 F/F). - nickel increment to the upper plate estimate (245 ?) yicid alate can be estimated by adding an 80 F g Approach 4 s L Guide Rev 2 predictions of the lower plate shift (181 F). l estimated from the ratio of the shift of the YR upper plate to the corresponding shift compositionally similar ASTM A302B Reference Correlation Monitor (RCM) steel irradiated in the same cupsulel. This approach assumes that the behavior of the R is consistent with predictions of the Reg. Guide 1.99 Rev 2, which is generally the . i At the higher fluence the RCM/YR upper alute ratio is 320/225 = 1.42. The nominal l tempernt' re correction is assumed to be 1 F/d (see below). This procedure yields a u plate shift estimate of AT = 1.42x(181+50) = 328 F. L i Approach 5' Data on low copper steels (<0.1%) from the French reactisurveillance program can b - used to estimaic the temperature dependence of embrittlement and the matrix (co independent) contribution at 500 F for low flux irradiation conditions 17. The results of . shown in Figurc 6. The data at various temp /cm2. 'ihe square fit) to arommon fluence of 2.7x1019 eratures were interpolated (by a In in least - n range is a nonical-1.07 F/F.'The shift (assumed to be primarily due to the matrix ' 160 F33. lience this approach yields a total estimated shift is 31 E Recommendation t i Dased on the consistency of Approaches 2 to 5, I recommend a 1990 shift estimate for the YR lower plate of 325 F. Note that this is somewhat less than the preliminary trend curve estimate of about 3f;0 F but somewhat higher than what would be found from using y nominal "cycball" mean estimate for the mixed data set shown in Figure 4. l

6. Welds Shift Estimates Given the uncenuintics about the composition of the welds, temperature effects, initial o

properties, coppet. nickel synergisms and the like,1 would recommend using the Eq. I to estimate for the axial weld of 230 F and for the circumferential weld of 360 F. Assuming a matrix shift contribution of 160 F the circumferential weld shift is consistent with a precipitate contribution from a plausable effective copper content of 0.34%. Note o

u some steels shown in Figure 4 with relatively high copper und nickel contents have lowe shifts. Indeed, the " bounding" curve was set by a plate containing only 0.21% Cu and 0.17% Ni, presumably due to some undefined source of extra " sensitivity". llence, ste - with both extra sensitivity t,nd higher nickel and copper contents may experience eve higher shifts then the bounding curve in Figure 4. \\;

7. Uncertaintles 1

uneenuinties. I believe the values may be somewhat c not excessively so. Indeed much higher plausable estimates could be generated in some cases (e.g. see Hiser's ana,ysis ).1.arge unecrtaintics are associated with the eff l 2 flux and other variables not eansidered, temperamre coastdown (irradiations belo the very limited data base at 500 F, lack of information on compositions and initial properties of the actual vessel materials and the potential for very low upyer.thelf e (which I believe could well be less than 30 ft lbs in some cases. Jn view considerations, I would recommend that a one standard deviation uncen)alnt lea >t) 40 F be included in any probabilistic nr bounding behavior analysis. y estim 1

8. Summary 4

L L To suntmarize, my recommendations on 1990 YRV shift estimates are: Upper Plate 245 F Lower Plate - 325F Axial Weld 230 F Circunderential Weld 360 F 1 further recommend use of a minimum error estimate of One Standard Deviation 40 F

9. References

1. Reactor Presure Vessel Evaluation Report for Yankee Power Station, YAEC No.1735 (July 1990)

2. A.L Hiser, personal communication

3. G. M. Gordon and li.H. Klepfer, in liffects of irradiation on Structural Materials, ASTM STP 426, p48 (1967)

4. G. R. Odette and G.E. Lucas, Irradiation Embrittlement of LW11 Pressure Vessel Steels, EPRI NP 6114, (1989) j

5. R. A. Wullaert, D. R. Irctund and A.S. Tetelman,in Irradiation Effects on Structural Allovs for Nuclear Reactor Aonlientions, ASTM STP 484, p 20 (1970)

'q

6. G. R. Odette, P.M.' Lombroto-and R. A. Wullacrt, in' Effects of Radiatinn' on 4 m

- Materin1s: Twelfth 1ntemnnonni Svoosium, ASTM S*1? R70,pH40 (1985) 1

7. T. J. Williams, P. R. Burch, C.A. English and P.H.N. de la cour Ray, in Proe of the Third Internationni Svmnosium in Environmental DerradnMon of Nuclear Power Svstemi~

. p 121 (1988).

8. A. L. Lowe, in Effects of Irradiation on Materials: 14tb Internationni Svmnosium Vol. 2 ASTM STP 1046, p201 (1990)

Pachur, Evalontion of HR3 Materials Metallureical Trend Curves. Draft Report, Sept

10. J. R. llawethorne, Rndintion Effects Information Generated on the ASTM Reference Correintion. Monitor Steels. ASTM Data Series Publication DS 54 (1974) l'l. Rediation Embrittlement of Reactor Vessel Materials, Regulatory Guide 1.99 Revision

2. U.S. NRC (1988)

12. G. R. Odette und G. E. Lucas, in Effects of Irradiation on Materints: 14th International Svmoosium.V2 ASTM STP 1046, p323 (1990)

13. G. R. Odette and G. E.1.ucas,in Radiation Fmbrittlement of Nuclear Reactor Pressure Vessel Steels: An internationni Review V2, ASTM S*1? 909, p206 (1986)

14. G. R. Odctte. In Proe of the Second international Svmnoslum in Environmental Derradation of Noelent Power Svstems, p 295 (1986)

15. G.E. Lucas'and G. R. Odette, Ibid p. 345

-16. F. W. Stallmann, Analysis of the A302B and A533b Standard Reference Materinis in Surviellance Cactules of Commercial Power Reactor _s, NUREG/CR 4947:ORN1/l'M-10459 (1988)

17. C. Brillaud and F. Hedin, In. service Evaluation of French Pressurized Water Reactor

-Vessel Steel, preprint of paper sub:nitted for publication in Effects of Radiation on Materints: 15th Svmoosium ASTM STP(to be published)- t

i. r

E l6 pg j

i -1 1 l. i r. ( i g-1I a. E l $100 I I l l b 4 (t = 0.14 x 10n/cm* $t - 0.9 x 10'*nicm* T-299C (t - 0.36 x 10n/cm* g T = 305*C .I I t T = 285*C - -1 I 30 900 1000 1100 800 900 1000 1100 800 900 1000 1100 I -I-Austenitizing Temperature (*C) Austenitizing Temperature (*C) Austenitizing Temperature (*C) ? Lt. Figure 1 Yield stress changes as a function orausterizing temperature of a UCSB plate containing about 0.40% copperand 0.86% nickel. h'_ s ? = l 1-CaOG % WR .4 d.--- - ~ - '~ ~ ~ ' ' ~

[ a ~ ical Microstructures of Coarse Grained Model A533Bl St i pt ... =. Temper 664 C,4 hrs, AC/ Stress Relieve 600,40 hrs, FC .= Cu Ni P T - 900 C Cu Ni-P o T n o 0.40 0.001 0.005 A-0.41 0.86 0.005 A = 1000 C wege annas a$f M R M a l f*&dil E k!"M Gd H id Figure 2 Optical micrographs (x400) showing the similarity in the coarse grain size of al; p f' PK (intermediate nickel) and LA (Iow nickel). t N4M27 4 }- + i ~- ?

O~ p y 4 [+. 1150 ~ s i W . (a) i LA 0.4Cu/0.001Ni/0.065P S, $t = 1;1 x'10~n/cm 2 4 Q".! "c .[2.5 MPafC 2 100 L N 50- ~ 280 290 l 300 310 T (*c) 's1 150i i. i L i i . (b)l i PK-0.41Cu/0.005 P R I100 50 MPa/%Nig l k o ( *LA-0 40Cu/0 005 $t = 0.9 x 10 8n/cm2-1 T - 305*C i P 50. 0-0.2 0.4 0.6 0.8. 1.0 Ni (%) Figure 3 of a course grained steel (LA); b the nickel de ess increase L yloid stress changes in coarse gr)ined steels. (LA ar4d FX) a oninduced ,w,

[;,ms %.f, - I? ,y . ~ 1

800, i

L ' - ~ ' d' Z L: O-H 400 4 [ n 200 LL: b L A 8-O BR3 + 1F/F 100 L e BR3 x C i o D YRP-1x$tnom. 50 ~ A YRP 2x$tnom, 25 I i O.1 1 10 100. $t(10'9n/cm, E>1MeV) 2 Figure 5 Yankee Rowe Upper Plate (YRP) and adjusted BR3 shift data versus flu ll 1 l-L 1 1 Ofcast?? I

s ch' } l I-r .i I b i 90 i i i i i i Cd/Ni/P -l f $t = 2.7.x 10"n/cm .e l0.09/0.65/0;0121 1 2 v 80 O 0.08/0.65/0.009 l Chooz 0 0,09/0,64/0.017-u Plate C- ,1,07'C/ C 'b 70 ( 60 ChooztO - Bugey 2 ~ Plate B u Plate C2h 50 250 260 270 280 290 T (*C) i . Figure 6 Interpolated shifts at 2.7 x 10"n/cm as a function of temperature from 1 2 the French surveillance data base. 'l I e mu t. s tst t l ', k s. . - -....}}