Moon Moon Devi. INO.

Transcription

1 Moon Moon Dvi. INO.

2 Plan of Th Talk: Motivation. Nutrino intractions and cross sctions. Diffrnt Exprimnts to masur nutrino cross sctions Dscriptions. Rsults. Conclusion.

3 Motivation: To study nuclon structur. To prdict rats of signal and background vnts for nutrino oscillation sarchs.

4 Nutrino Intractions : Nutrino intracts only by wak intraction, by xchang of a gaug boson. Wak intractions ar lss probabl to tak plac compard to othr intractions, as th masss of W and Z bosons ar larg.(w~80gv, Z~91GV). Ths intractions ar of two typs: chargd currnt intraction(cc) and nutral currnt intraction(nc). CC intraction is mdiatd by a W boson. A nutrino intracting with a nuclon xchang charg with th nuclon and turn into chargd lptons. NC intraction is mdiatd by a Z boson. For both th intractions, svral procsss xist lik lastic, pion production, dp inlastic scattring,cohrnt,rsonant and diffractiv.

5 Nutrino-lctron intraction : For lctron nutrinos th lastic scattring with lctrons can b mdiatd by chargd and nutral wak bosons (W and Z) W 0 Z Th lastic scattring of muon and tau nutrinos from lctrons is mdiatd only by th nutral boson. Th inlastic scattring procsss ar causd only by th chargd currnts. 0 Z W

6 Th cross sction formula for purly lptonic intractions: Th cross sction formula for tau nutrinos ar th sam as for muon nutrinos. Rf.

7 Nutrino-nuclon quasi-lastic scattring: n p p n ( ) p ( ) p n W p n W p ( ) ( ) CC CC NC p Z p Form factors introducd sinc proton, nutron not lmntary. Dpnd on vctor and axial wak chargs of th proton and nutron.

8 Dp Inlastic nutrino-nuclon scattring: ν l + N l + X Parton modl is usd to mak prdictions for dp inlastic nutrino-nuclon scattring. Nutrino bams from pion and kaon dcays, dominatd by muon nutrinos ar usd to study this procss. N X N X Sinc parity is not consrvd in wak intractions, thr ar mor structur functions for wak procsss, lik nutrino scattring, than for lctromagntic procsss, lik lctron scattring. Gnral form for th nutrino-nuclon dp inlastic scattring cross-sction, nglcting lpton masss and corrctions of th ordr of M/E: d, dxdy 2 GFME 2, 2, y, 1 y F2 y xf1 y xf3 2 Th functions F 1, F 2 and F 3 ar th functions of Q 2 and. In th scaling limit thy ar th functions of x only.

9 Singl pion production: p, n W D p,n p, n Z 0 D,0 0 p,n CC1 NC1 0

10 Nutrino-nuclon inlastic cross sctions formula: For nrgis < 1 GV : For vry high nrgis (50 GV < E < 250 GV): Nutrino-nuclon lastic total cross sctions formula: Rf.

11 ν Cross Sctions Pictur :

12 NuTv (Nutrinos at th Tvatron): It is a fixd targt dp inlastic nutrino scattring xprimnt at Frmilab( ). Sign slctd bamlin. SSQT to produc a high purity nutrino or antinutrino bam. Dcay pip. Shild. Bam is almost pur ν or ν. (ν in mod 310-4, ν in mod ). Bam only has ~1.6% lctron nutrinos. Sign slction - St ν /ν typ - Rmov ν from K long (Bkgnd in prvious xps.) Uss a continuous calibration bam running concurrntly with data taking.

13 NuTV Dtctors: Targt/Calorimtr: 168 F plats (3m 3m 5.1cm) 84 liquid scintillation countrs (triggrs th dtctor & masurs visibl nrgy, nutrino intraction point, vnt lngth.) 42 drift chambrs. Solid F magnt masurs μ momntum/charg. Continuous Tst Bam simultanous with ν runs - Hadron, muon, lctron bams - Toroid and calorimtr rspons ar mappd. Toroid Spctromtr

14 Rsults: Th diffrntial cross sction pr nuclon ax a function of x, th Bjorkn scaling variabl, and y, th inlasticity, can b xprssd in trms of th rlativ flux as function of nrgy and diffrntial numbr of vnts as, d dxdy 2 E 1 E d 2 E N dxdy Data slction critria : a good muon track for accurat momntum masurmnt, minimum nrgy rquirmnts : E Had >10 GV, E μ >15 GV, E ν > 30 GV. Nutrino Rlativ flux dtrmind from a sampl at E y Had low hadronic nrgy (< 20GV).As E 0,th intgratd numbr of vnts ar proportional to th flux. Dtctor simulation is usd. Diffrntial cross sctions for nutrinos and anti nutrinos at E ν =85GV (for difffrnt x).

15 Masurmnt of Winbrg angl: Also, this xprimnt masurd th valu of th Winbrg angl utilising th Paschos- Wolfnstin Rlation NC NC 1 2 R sin W 2 NC/CC Evnt Sparation : CC CC CC Evnt: Long Evnt Lngth NC Evnt: Short Evnt Lngth Statistical sparation of NC and CC vnts basd on Evnt Lngth R xp Short vnts Long vnts NC candidats CC candidats Th rsult! Masurd valu : ν : ± (stat) : ±0.0016(stat) Givs a discrpancy of ~ 3!

16 K2K: Supr-K as th far dtctor to confirm atmosphric nutrino oscillations. Nar dtctors to obsrv un-oscillatd nutrinos and to masur nutrino cross sctions. Th K2K nar dtctor nsmbl 1 kton watr crnkov dtctor. A scintillating fibr watr targt trackr (SciFi). A solid scintillator trackr (SciBar). A muon rang dtctor (MRD). 12 GV protons on Al targt at KEKa ν µ bam (97% purity)of pak nrgy 1.3 GV. Th first to publish updatd nutrino cross sction masurmnts in th 1 GV rang.

17 Rsults: Nutrino intractions on both carbon and oxygn-basd targts was studid. 1 kt Watr Chrnkov Watr targt Th first masurmnt of NC π production in watr. Th ratio of nutral currnt singl π 0 production and th total CC cross sction is calculatd to b σ NC1π0 /σ CC = 0.063±0.001(stat)±0.006(syst). This valu agrs with th mont Carlo xpctation of SciFi Watr targtth first masurmnt of axial mass M A in QE intractions in watr vnts from th K2K-I run and 5967 vnts from th K2k-IIa run. Data abov Q 2 >0.2 GV 2 ar fittd to obtain M A as, M A = 1.18±0.03(stat)±0.12(syst). 20% highr than prviously masurd.

18 Rsults: SciBar dtctor data Carbon targt First sarch for CC cohrnt π + production at low nrgy. Evnts with two rconstructd tracks ar slctd. MC prdicts xcss vnts at low Q 2. But fitting Q 2 distribution yilds 7.6±50.4 vnts Expctd 470 vnts. No vidnc for cohrnt production.

19 SciBooNE (SciBar+Boostr Nutrino Dtctor): Boostr bam Dcay rgion 50 m SciBooNE 100 m 440 m MiniBooN E Dtctor Uss Boostr Nutrino Bam (BNB) at FNAL (on axis-100 m from B targt). Th nrgy pak of th ν bam is 0.7 GV. Th dtctors: SciBar, Elctromagntic calorimtr, Muon rang dtctor. 8 GV protons from Boostr with th rat bing 4 X protons/1.6μs hit B targt (lngth 71 cm, diamtr 1cm). and producs msons,i., pions and kaons. Th targt is surroundd by magntic focusing horn such that th polarity can b changd to gt ν and anti-ν. This xprimnt collctd both nutrino and antinutrino data in a priod from Jun 2007 to August 2008.

20 Rsult: ν µ CCQE vnts. Lowr statistics than MiniBooNE, but bttr Q 2 rsolution Highr statistics than K2K SciBar, and lowr E ν. Highr vnt purity - lss rsonant contamination Confirm M A masurmnt with low nrgy nutrinos and low-a targt. NC1 0 dtction. Sam dtctor usd to masur NC1 0 in two bams. ν µ bar CC1π Cohrnt procss Nutrino vnt Anti nutrino vnt

21 MINERνA-Main Injctor Nutrino Exprimnt ν-a: It is a ddicatd nutrino cross sction xprimnt plannd to run in th NUMI (Nutrinos at th Main Injctor) bamlin at Frmilab. Th dtctor will b placd upstram of th MINOS Nar Dtctor in th NuMI bam lin. It will masur nutrino intractions across a wid rang of nutrino nrgis (1-20GV) as providd by th NuMI bam. Th dtctor is bing placd upstram of th MINOS Nar Dtctor in th NuMI bam lin. It will b th first dtctor to hous a wid spctrum of nuclar targts (C to Pb) starting with thr targt matrials C, F and Pb. Sks to masur low nrgy nutrino intractions.

22 MINERνA Dtctor dtails: Cryotargt Outr Dtctor (OD) Layrs of iron/scintillator for hadron calorimtry: 6 Towrs LH 1 towr VtoWall Downstram Calorimtrs: 20 moduls, 2% activ, shts of lad (Elctromagntic Calorimtry) or stl (Hadronic calorimtry) btwn scintillator plans. Sid Calorimtrs: 2 thin lad rings for sid Elctromagntic Calorimtry, 4 layrs of instrumntd stl Innr Dtctor Hxagon X, U, V plans for stro viw 4 towr Lad Shts for EM calorimtry

23 MINERνA Expcts: CCQE : Expct ~800,000 vnts Prcision masurmnt of σ(eν) and dσ/dq ovr a wid dynamic rang Prcision dtrmination of axial vctor form factor (F A ), particularly at high Q 2 Study of A-dpndnc (C, F and Pb targts) Cohrnt : Diffrnt nuclar targts will allow th first masurmnt of th A-dpndnc of σ coh across a wid A rang. CC1: Expct ~ 1.6M total rsonant, 1.2M 1π. Prcision masurmnt of and d/dq for individual channls. Dtaild comparison with dynamic modls, comparison of lctro- & photo production. Study of th rsonanc-dis transition rgion. Study of nuclar ffcts and A- dpndnc. NC1p 0 : Clan idntification of π 0 s. Extrmly good momntum rconstruction. Running in >1 GV nrgy mod would allow undrstanding of NC1π 0 background.

24 Evnts MINERνA Challngs: Exprimnts using magntic horns suffr from wrong sign (WS) backgrounds in mod. For th Boostr Nutrino Bam, WS backgrounds compris ~35% of th total vnt rat. Ths must b rmovd from vnt sampls for accurat antinutrino cross sction masurmnts. Difficult for dtctors without magntic filds. (35%)

25 MIPP: Main Injctor Particl Production Exprimnt: A fixd-targt particl production xprimnt. TPC, Bam Chambr, RICh (Ring Imaging Crnkov Countr). Calorimtr. Primary proton bam of momntum120 GV/c, scondary p,k and π bams of momntum 5-80 GV/c from NUMI. Multipl targts including liquid Hydrogn,and Uranium tc.) It prmits dtaild cross sction masurmnts.

26 Conclusion : W had a ovrviw of diffrnt nutrino intractions and cross sctions. W wnt through th dtails of diffrnt xprimnts lik NuTV,K2k,SciBooNE,MINERνA,MIPP. W had a viw of th rsults both obtaind and xpctd from th xprimnts.

27 Rfrncs: Nutrino Physics by Kai Zubr. Massiv nutrinos in Physics and Astrophysics by R. N. Mohapatra and P. B. Pal. Physics of nutrinos and application to astrophysics by M. Fukugita and T. Yanagida. Quarks and Lptons by F. Halzn and A. D.Martin. Nutrino Cross sction and scattring physics, Flming.B. Low nrgy cross sctions from K2K,MiniBooNE,SciBooNE and MINERνA,By Zllr G. P. arxiv: hp-x/ v Napls. D. t al, NUTEV cross sction and structur function masurmnts. Nutrino Cross Sction Exprimnts, by, Wascko M. hp-x/ , Kato I. Th Frmilab MIPP xprimnt,solomy N.

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