Give a reaction between two nucleons, similar to Eq. niwh1f)0znb vjefv)a0:pw (. 32-4, that could produce a wnij. fwp0z)( af01nev):bh v $\pi^0$.

  If a proton is moving at very high speed, so th1fw5dx.yyu9;e b /jp nat its kinetic energy is much greater1 j5fux ;/y.p9yndebw than its rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom,1lisdvp: t 7.ux ;p oa4c)uf0i" made up of the antiparticles to the constituents of normal atoms, consist of? What might hap:0ol .uvp)1difipa tc74s; u xpen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromakhc/*x q,i y,d-p zry+ dr0o(zgnetic interaction?

Does the presence of a neutrino among the decay products of a particle necessar / ku6g7n;bqywq 2b)eoily mean that the decay occurs via the weak interaction? Do all decays kb y 6qgeo)/ unqwb27;via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak intera3fzu0bjy 3 9 p8a-ozkrction even though the neutron and one of its decay products (proton) kpbr30 afzu 8y9-joz 3are strongly interacting?

Which of the four interactions (strong-4frm6,5 cee1xzab s l, electromagnetic, weak, gravitational) does an electroz xl se6bm f1cr4ae5,-n take part in? A neutrino? A proton?

Check that charge and baryon n;b+v17 ld, k cdk/tlwl pmc 08ozzb1+cy,g;ofumber are conserved in each of the decays in Table y, blgw 1/+;lbfdc0d+l oockv,p;1c8m7zt zk32-2.

Which of the particle decays in Table 32-2 ot/fuw-t ys)3 ji1g0qkccur via the electromagnetic interactio qu/gt1j tswiy-fk3)0n?

Which of the particle decays in Table 32-2 occur ndildl7c3jemm 5r*.r-j, nz;by the weak interaction?

By what interaction, anystni)a )k)p9 4eg ny4d why, does $\Sigma^0$ decay to $\Lambda^0 + \gamma$? What about $\Xi^-$ decaying to $\Lambda^0 + \pi^-$?

The $\Delta$ baryon has spin $\frac{3}{2}$, baryon number 1, and charge states $Q = +2, +1, 0, -1$. Why is there no charge state $Q = -2$?

Which of the particle decays in Table 32-4 occur via the electromagne tpurxn(9,dh+ n/0hnz tic interachtdux/9rn h ,z+ n(p0ntion?

Which of the particle decays in Table 32-4 occur by the weak interaction:xsv 6wr) 3 srfnxm+o+?

Quarks have spin $\frac{1}{2}$. How do you account for the fact that baryons have spin $\frac{1}{2}$ or $\frac{3}{2}$, and mesons have spin 0 or 1?

Suppose there were a kind of "neutrinolet" that was mal6 zy rve4u(k-ngc*f+ssless, had no color charge or electrical charge, and did not feel the weak force. Could you say that this particle even exil4f verny-( c+kgzu*6 sts?

  Is it possible for a p 9rul -1-mp14,zzl ra mph v:*0yvvxsoswn61j article to be both
(a) a lepton and a baryon?  ----待选择----yesno 
(b) a baryon and a hadron? ----待选择----yesno 
(c) a meson and a quark? ----待选择----yesno 
(d) a hadron and a lepton?  ----待选择----yesno 
Explain.

Using the ideas of quantum chromctz.ol *tfnv.lq 48 p,odynamics, would it be possible to find particles made up of two quarks and no antiquar8n 4tlto *.,pvcf.qzl ks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when they are inside 2vp/:k1ih zjz the nucleuszkzp:/j2vi 1 h?

  Is the reaction $e^- + p \to n + \nu_e$ possible? Explain.  ----待选择----yesno 

Occasionally, the $\pi^+$ will decay by the following reaction: $\pi^+ \to e^+ + \nu_e$. Which of the four forces in nature is responsible for this decay? How do you know?

  What is the total energy of a proton whoswfs97/hnl 0q l : zh 7rbv.4u56hcfghye kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35 x:y+ :lajcck.-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotronwpf8 : yz.wf/:kd 4j 4lly5chh in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very high-energy p gz:9. xui;6bo:oanvp:jqc0 jroton in the 1.c zaj u;xpgb0:vj6 :noqo :i9.0-km-radius Fermilab accelerator? T =     $ \times 10^{-5}\ \text{s}$

  If $\alpha$ particles are accelerated by the cyclotron of Example 32-2, what must be the frequency of the voltage applied to the dees? $f$ =    $ \times 10^7\ \text{Hz}$

  (a) If the cyclotron of Example 32-2 accelnl d+) nqh;+t2fbi qc)erated $\alpha$ particles, what maximum energy could they attain? What would their speed be? KE =    v =    $ \times 10^7\ \text{m/s}$
(b) Repeat for deuterons ($^2\text{H}$).KE =    v =    $ \times 10^7\ \text{m/s}$
(c) In each case, what frequency of voltage is required? $f$ =    Hz

  Which is better for picking out details of the nucleus: 30ihv;v. li-0pvq*iq2b4s l tx ,-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of4vvi-x0 piql2ls*q,vt ih; b. a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the d.hsgn dl4w.t)cch): *:mf4nx cahb 1oees of a cyclotron is 55 kV. How many revolutions do protons make to reach a kinetic energy o wn) 1tnmhs*fc : cx:b4h)dg ..lcoha4f 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengt:z.nql zg*mu))z vp i111h cuah ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.an;jew etw +abfu.5l4o q.;y/99 omy s0 m is to accelerate deuterons ($^2\text{H}$, mass $= 2.014$ u) to an energy of 12 MeV.
(a) What is the required magnetic field?$\approx $    T
(b) What frequency is needed for the voltage between the dees?$\simeq $    Hz
(c) If the potential difference between the dees averages 22 kV, how many revolutions will the particles make before exiting?$\approx$    $\ \text{revolutions}$
(d) How much time does it take for one deuteron to go from start to exit? $\Delta t$ =    $ \times 10^{-6}\ \text{s}$
(e) Estimate how far it travels during this time. distance =    m

  The 4.25-km-radius tunne s.qcw er ryi8t:/s;wjk /ke+5l that will be used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. Wha8s.w:w5e/si/rektj q cy+ ; rkt magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds t qn.i -tsi,f8j h cv:2*ejtqp:o bring the energies of the stored protons from 150 GeV to 1.0 TeV. The acceleration i,v:-he8cjp:. qts2 itj*n fqi s done once per turn. Estimate the energy given to the protons on each turn. (You can assume that the speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particle (;0dqy bm;a4tnxa0rr*sohpy :z1 w:u5charge $e$) in a synchrotron, in the relativistic limit ($v \approx c$), is given by $E\ (\text{in eV}) = Brc$, where $B$ is magnetic field strength and $r$ the radius of the orbit (SI units).

  What magnetic field intensity is nsx;9bqhh7 u n 60ppl2xeeded at the 1.0-km-radius Fermilab synchrotron for 1.0-TeV protonsxl690hu;b 7ph n2qxps? B =    T

  How much energy is released in tvtr j(aum7)7y7s gr0dhe decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is relea hi;g/hox9gn03(c ufnsed when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-ant12,z fz k )s5eevh:tdr ga7l4tineutron pair?    MeV

  Estimate the range of the strong force if the mediating particle were tog s9dt:3 ohk)*(rf xjhe kaon instead of t:oo hs rx)ft9* dj3(kghe pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal spes k7.8iec7q hkeds. What minimum kinetic energy must each have i.ch8i esq77k kf a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must two neutrons each have if they ,:o:.oq (jtosq a1j,lkm u+rware traveling at the same speed:l1jo, st aur+m.:k,j qo(qwo toward each other, collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak fkhadq okp1 mn 1yz6y07x s5:e.orce using Eq. 32-3, given the masses of the W and Z particles as about 8mq1xen6 phsy5d k:o.1y7a z0k 0 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths os yvj-2vmc:.l*if 2nsw7em9w f the two photons produced when a proton and antiproton at res7wf *-9lmenw 2v.v j:csi ysm2t annihilate? $2m_0c^2$$\approx $    $ \times 10^{-15}\ \text{m}$

The $\Lambda^0$ cannot decay by the following reactions. What conservation law is violated in each of the reactions?
(a) $\Lambda^0 \to n + \pi^0$
(b) $\Lambda^0 \to p + K^-$
(c) $\Lambda^0 \to \pi^+ + \pi^-$

  For the decay $\Lambda^0 \to p + \pi^-$, calculate (a) the Q-value (energy released),Q=    MeV
(b) the kinetic energy of the p and $\pi^-$ assuming the $\Lambda^0$ decays from rest. (Use relativistic formulas.)
$KE_p$ =    MeV
$\text{KE}_{\pi^-}$ =    MeV

Show, by conserving m;lo 7:fpzb*kw vo0e)g diq7-nomentum and energy, that it is impossible for an isolated electron to r -*bnif0zwdv:pk7o e;gl) oq7 adiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photonsn)wrvedg-2, (y ka ,*dtv b/gr produced when an electron and a positrg/(yb ,rd,dnvae )*rk vg w-t2on, each with 420 keV of kinetic energy, annihilate head on? $\lambda $ $\approx $    $ \times 10^{-12}\ \text{m}$

  In the rare decay $\pi^+ \to e^+ + \nu_e$, what is the kinetic energy of the positron? Assume the $\pi^+$ decays from rest. $\text{KE}_{\text{e}^-}$ =    MeV

Which of the following reactions and decays are 5. szmefg5 /un(qczr( possible? For those forbidden, explain what lau(s z5ge( qz./n c5frmws are violated.
(a) $\pi^- + p \to n + \pi^0$
(b) $p \to e^+ + \nu_e$
(c) $p + p \to p + e^+ + \pi^+$
(d) $\pi^- \to e^- + \bar{\nu}_e$
(e) $\mu^+ \to e^+ + \nu_\mu$
(f) $p \to n + e^+ + \nu_e$

  Calculate the kinetic energy of each of the two products ik(thi nth;qd:9i5afjj b *jxa f/-; )nn the decay $\Xi^- \to \Lambda^0 + \pi^-$. Assume the $\Xi^-$ decays from rest.
$\text{KE}_{\Lambda^0}$   MeV
$\text{KE}_{\pi^-}$   MeV

  Could a $\pi^+$ meson be produced if a 100-MeV proton struck a proton at rest? What minimum kinetic energy must the incoming proton have? $\text{KE}_{\pi^-}$ =    MeV

  Calculate the maximum kinetic energy of the electron in the dec6.dafp b*z:jyay $\mu^- \to e^- + \bar{\nu}_e + \nu_\mu$. [Hint: In what direction do the two neutrinos move relative to the electron in order to give the latter the maximum kinetic energy? Both energy and momentum are conserved; use relativistic formulas.] $\text{KE}_{\text{e}^-}$    MeV

  Use (Fig. Below) to estimate the energy width and ttw7r ;larkks/fm7ie .vu.33rhen the lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width orl/vm ;h1 pf/ t;tlyp7f the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of mtp a1sp+*kce 3ip,n,the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or 2niwd a 7p+;fnuncertainty) of
(a) $\pi^0$, $\Delta E$$\approx$    keV
(b) $\Sigma^0$? (See Table 32-2.) $\Delta E$$\approx$    keV

The $B^-$ meson is a $b\bar{u}$ quark combination. (a) Show that this is consistent for all quantum numbers. (b) What are the quark combinations for $B^+$, $B^0$, $\bar{B}^0$?

Which of the following decays are possible? For tkqdgw4p l8tbu.xv;.rm fz ki6j 38 r+yi,o8m7hose that are forbidden, explain which laws are violyrwzd8.. oftv73 8ukmprl6i j,8g bmq xi 4+;kated.
(a) $\Xi^0 \to \Sigma^+ + \pi^-$
(b) $\Omega^- \to \Sigma^+ + \pi^- + \nu$
(c) $\Sigma^0 \to \Delta^0 + \gamma + \gamma$

What are the quark combinations that can form (a) a neutron, (b) an a9 *z xjw35qd s9.xqvkintineutron, 5x s*dw9q xjzq.vk 3i9(c) a $\pi^+$, (d) a $K^-$?

What particles do the following qua0bj1vazlf2f8)t : 6ydrp uye6rk combinations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination needed t * d (4:fow+8wcdink6fdckp*r o produce a $D^+$ meson ($Q=B=S=0, c=+1$)?

The $D_s^+$ meson has $S=c=+1, B=0$. What quark combination would produce it?

Draw a possible Feynman diagrg*q r cl9bk5f6am using quarks (as in Fig. Below) for the reaction lqgcr5 b6k f*9$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram f1 rfj(83ei6g 8yccqi l2 au8zpor the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? What is it.ca sy(1 /tl;hkhjf)sa *; nzms wavelejs.zf;(1 )h/ym h;lt*aacnsk ngth?
$\approx$    $ \ \text{GeV}$
$\lambda$ $= $    $ \times 10^{-17}\ \text{m}$

  Assume there are $5.0 \times 10^{13}$ protons at 1.0 TeV stored in the 1.0-km-radius ring of the Tevatron.
(a) How much current (amperes) is carried by this beam?I =    A
(b) How fast would a 1500-kg car have to move to carry the same kinetic energy as this beam? v $\approx $    $ \times 10^2\ \text{m/s}$

  Protons are injected into the 1.0-km-radius Fermilab Tevatron wfeme 2v cg3.*(ytcu-q ith an energy of 150 GeV. If they.tc2mu- g(* y e3vfeqc are accelerated by 2.5 MV each revolution, how far do they travel and approximately how long does it take for them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is releasigk r, :f-uul36ew b-wed when an electron and a positron annihilate each rfubk3wu-ewlg ,i 6:- other? $E_{\text{total}}$=    MeV
(b) How much energy is released when a proton and an antiproton annihilate each other? (All particles have $KE = 0$.) $E_{\text{total}}$ =    MeV

Which of the following reactions are possiblebmz(;;zbja,sy 1vzp .e;2 pmh1e lq: 2hn;zh z, and by what interaction could they occur? For those forbidde2; hsez,1p;vme zm;2.j:hz zqhab 1;b lynz p(n, explain why.
(a) $p + \pi^- \to K^+ + \Sigma^-$
(b) $p + \pi^+ \to K^+ + \Sigma^+$
(c) $p + \pi^- \to \Lambda^0 + K^0 + \pi^0$
(d) $p + \pi^+ \to \Sigma^0 + \pi^+$
(e) $p \to \pi^+ + e^- + \bar{\nu}_e$

Which of the following reactions are pos/yqff*5 9g4uwqbjb 2 /dz/yzssible, and by what interaction could they occur? For those forbidden9qy bz/d by/usjgzf4/2 f*q w5, explain why.
(a) $p + \pi^- \to K^0 + p + \pi^0$
(b) $p + K^- \to \Lambda^0 + \pi^0$
(c) $n + K^+ \to \Sigma^+ + \pi^0 + \gamma$
(d) $K^- \to \pi^- + \pi^0 + \pi^+$
(e) $\pi^+ \to e^+ + \nu_e$

One decay mode for a qapden23ot 2jn *ja+1 .uuv0i va k*u3$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the eleu qb5ry rtu3du26/9n /nbck6hx9pjc *ctroweak theory at about $10^{-18}\ \text{m}$. Show that this corresponds to an energy that is on the order of the mass of the W boson ($M_W c^2 \approx 80\ \text{GeV}$). $mc^2$$\approx$   GeV

  The mass of a $\pi^0$ can be measured by observing the reaction $\pi^- + p \to \pi^0 + n$ at very low incident $\pi^-$ kinetic energy (assume it is zero). The neutron is observed to be emitted with a kinetic energy of 0.60 MeV. Use conservation of energy and momentum to determine the $\pi^0$ mass. $E_{\pi^0}$ =    $MeV/c^2$

  Calculate the Q-value for each of the reactions, Eq. :;hj 8+ ,m(,znfu dpqpalmzhet**qwp d5 )0lm 32-4, for producing a pion. penq pd m8 pf,qdlwz m,+*mz;)*( hhj5t0ula: $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reacti a7 1r11akglofon $\pi^- + p \to \Lambda^0 + K^0$ when negative pions strike stationary protons. Estimate the minimum pion kinetic energy needed to produce this reaction. [Hint: Assume $\Lambda^0$ and $K^0$ move off with the same velocity.]
Q =    MeV
$\text{KE}_{\pi^-}$ =    MeV

  How many fundamental fermions are there in a water mol9-ktd6lmplco//m(t becule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two pioyw 070z-4xps0qz u omons, 400 -zq0u o7ozsypm xw$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distancepsjfix4/g6 3h of $10^{-31}\ \text{m}$ in grand unified theory is equivalent to an energy of about $10^{16}\ \text{GeV}$. Use the uncertainty principle, and also de Broglie's wavelength formula, and explain how they apply. $\Delta E$ =    $ \times 10^{16}$GeV E =    $ \times 10^{15}$
(b) Calculate the temperature corresponding to $10^{16}\ \text{GeV}$. E =    $10^{28} K$

For the reaction $p + p \to 3p + \bar{p}$, where one of the initial protons is at rest, use relativistic formulas to show that the threshold energy is $6m_p c^2$, equal to three times the magnitude of the Q-value of the reaction, where $m_p$ is the proton mass. [Hint: Assume all final particles have the same velocity.]

  The lifetimes listed in Table 32-2 are in terms of propuusb g0i k 2rjzov tr5t+)hst)1:b+c*er time, measured in a reference frame where the particle is at rest. If a tau lepton is created with a kinetic energy of 450 MeV, how long wouldtr0b2sv+j :osuk5tr1 ih)b+uzt g*c) its track be as measured in the lab, on average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing partw;:4k/bwzx b qicle in the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to de-; ;d:czfdv00 i qcvgpscribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speqidojg,7 wsti5f .6b 17q uq-ded of light $c$ is the speed of a 7.0-TeV proton?