Give a reaction between two nucleons, similar ctr1 x; 1tdl.hs qa0i;to Eq. 32-4, that could produce a .1dtircqs x; ; t0alh1$\pi^0$.

  If a proton is moving at very high speed, so t:m dwyi ge;j1jw9f-+ lavr1 lvn:x t02hat its kinetic energy is much greater than its resg-v jlx2mv+;tif1 l r:w9dw:ne j0ay1t energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticles tw8x: kf1ku*1; poh guto the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, caut11;w k 8x:*oukpfgh me in contact with our normal world of matter?

What particle in a decavv1rd4pv0f4 j pb-.iby signals the electromagnetic interaction?

Does the presence of a neutrino amol9 5i 1qwd1vffpdc p) 0zny1vk+eb-s2ng the decay products of a particle necessarily mean that the decq ncfk sdv1l- 5fwydzbie) 1p19v0+ 2pay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays viarbww ./m8+gsf the weak interaction even though the neutron and one of its decay products (proton) are strongly inter+/smw8 wrf .gbacting?

Which of the four interactirs:q h jrvzo8f3 kpfn8(c9.d r+0m0 seons (strong, electromagnetic, weak, gravitational) does0d erv f r8(hmn.3cs:q ospk8f0jr+9z an electron take part in? A neutrino? A proton?

Check that charge and 3t+jvq vh2sk9 baryon number are conserved in each of the decays in Table 32-2 3kh vjt9sv2+q.

Which of the particle decays in Table 32-2 occur via the elek*sj(utf(:4 -t vgrvvctromagnetic interacts 4t-uv f(:kr*tg(v vjion?

Which of the particle decays in Table 32-2 occu)lzwzs 0, vuthj:j1 /ur by the weak interaction?

By what interaction, 6os w3m8p.cwhand 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 deci k3dylit6+pj- m,ul/ ays in Table 32-4 occur via the electromagnetic interactiym tji -kld3up/6 li,+on?

Which of the particle decays in Table 32-4 occur by the weak in juzpc2okub r d8r4p*k .v)*g9teraction?

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 mazlh - mryu j9)f 1unt ux,b78z0c5tl7wssless, had no color charge or electrical charge, and did not feel the weak force. Could you say that this particle even exh w5yltj - urntbcm789u7f)z 1, l0zuxists?

  Is it possible for a particlfj6qz1xzcbo4f2i:k rhcn,( 1e 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 chromodynamics, would it be pyrgmt l,5 7*lr*bfw+ mossible to find particles made up oftbl,l +mg*5 my*wr7fr two quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free byg (xw kvj,ap8qr+; c8ut not when they are inside the nucleus? ;8acp8,v (wrxj+qykg

  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 pr/0ojzfuc .i0lk,zz)o oton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelengtaa1di (y 1 7 bpuc7vc)u 6lnljdfn,(qwwb8l*/h of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic fielde qg-rp xuzf;5sy9vh9;c jy+2 is used in a cyclotron 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 proe exc+b04m iuw5lg 98cton in the 1.0-km-radius Fermiiegccwb9 e lx54 8u+m0lab 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 ac ;4gu 70m*azo*h h+i;igwlahccelerated $\alpha$ 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 )aw6-6ds*f (jn-cl0ny ssm rl nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of snm -(l -nja0y)sdl r6*wcsf6 their wavelengths with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kV. How m u;e+m60hr fmeany revolutions do protons make to reachfmu m;6h0+ ere a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengthpstu6sa-)hr ols , nr7w2x,c - ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m is to acceler ffa -t*v4b,cqkkea, 8ate 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 tunnel that will be used to house the magnets f+y,aoe l57i4c6rolwo or the Large Hadron Collide loo,w5co7r+4l6 ayier (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds to bring the energies f 7rq7rz5tq6d of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once per turn. Esrq7t 67f q5dzrtimate 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 a2ao6fr 9* ow(sedq* orm4d ee; particle (charge $e$) 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 needed at the 1.m.dzdn-+p *-am 4jff2sxcmk30-km-radius Fermilab synchrotron for 1.0-TeV protons? B kndmf 3f.saz -4c-dmm *+2 xpj=    T

  How much energy is r r ua9ad;r7gv.eleased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy g ,4m:y55ohpcgd/ gkiis released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron pai -gojx778cgewt pq(so;.4e-cd f5 vm fr?    MeV

  Estimate the range of the strong force if the mediating particle wek +z,m.myf rpr;so((p re the kaon inspy rsp, o;(zrfmk+.m(tead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other8 .xl)+gen xx; i,xtni with equal speeds. What minimum kineticxl,; x+gexi8.xn i t)n energy must each have if 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 thef*g txgqi*, 8vy are traveling at the same i,q*8g gfvt*xspeed toward each other, collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of /b,xy l ls(f1rthe weak force using Eq. 32-3, given the masses of the W anllb ,x y/sf1r(d Z particles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced when a proton and antiprmoi of s2h z)0l-88,kn*vie 2rlm +iohoton at rest annihilo i*f2 z) ,r-8mhk0nv+8elmh so2 ioliate? $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 momentum and energy, than2 g-gxc1 drp b8(ofl.(y,al at it is impossible for an isolated electron to radiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram ia21(lgb ,poa.8 dfy x- c(glrnn (Fig. Below)?

  What would be the wavelengths of the two photons produced when an electron aa nz4,-ncof,m0ey) n 1 s-bjywnd a positron, each with 420 keV of kinetic energy, annihi n)y4,s- bae0o ncjfz-y1wm, nlate 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 possible?9)r8c qmfpa g (c6s6ks For those forbidden, explain what laws are violaf6m( )a r69cs8gpqskcted.
(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 pry8wzpb vt2o-v ))t b0noducts in 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 icmlxg04o n ,/ att:z0xn the decay $\mu^- \to e^- + \bar{\nu}_e + \nu_\mu$. [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 ex,lh.5 zo9-fgzuwepea p8/(o .3jeot stimate the energy width and then the lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width oytf2 o 0m2w7hhf the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of -augr 7v, hs+zq8i:l gki:cm8the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (v1x: h*z9cvjeor uncertainty) 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 those thatyy3i5*;0:uvpaleq ap are forbidden, explain;y q py5a*uv :p0elia3 which laws are violated.
(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 flagko mzgau*f ffu9-ll 9+/6* vkn 41oorm (a) a neutron, (b) an antineutron, (u/ 69l*fk-ka+lozg194mffog *a lnv u c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combine rs82hemas +*ations 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 to 0dxbdw66d c; k2io2p+ b ch2bpproduce 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 Feynmahp dluipn,ul*4 /tq:4n diagram using quarks (as in Fig. Below) for the reactionhqlu4*p i4,p/ un lt:d $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for8hjj z6o1 2tui htp+7l the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton who2 )l iqxx;7;vnp)y tf :uc5pjudck/ .jse kinetic energy is 25 GeV? What is its wavelength? liknj ) cuqjp/2f :d.pcu)x;xy5 ;vt7
$\approx$    $ \ \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 Fermila ngmdla rjij31y;/8;h b Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and approximately how l drl;imnj8ah3 ;y g1/jong does it take for them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a positron annihild6 5+ wp.kzzda7 i-nolate each other?a-56p +dd nzzlowk.i 7 $E_{\text{total}}$=    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 possible, and by what interaction could thi( b pa-umm8wj2nob)y;)y gd(ey occur? For those forbidden, explain why;bi-dj8 )a( m wgony)mu2pb(y.
(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 possg i:yha b.wg0,.ol1smy,: senible, and by what interaction could they occur? For those forbidden, m .: ibey:.owg,g0 ynl sha1,sexplain 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 +zo wc6yuqls3 r;3og* $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in lzs1o,y(a,wa flx-, sthe electroweak 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 reactionsclt0e k0 *xqs(9rg:ab , Eq. 32-4, for producing a pion. bxs*e:g0 lcr(t0a qk 9$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value foxd ;i/k7i xl, wwccb76r the reaction $\pi^- + p \to \Lambda^0 + K^0$ 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 ap1wl (nb)ylk8 58eohd water molecule?    fermions

  A proton and an antiproton annihilate each other at rest and producoojpp vx2af 25p(n(r)qp m +s4e two pions, n 2sajp+ 4m)vpp(p5x 2r (oqfo$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called u 9:vsru(-a) ghl r) 3bctfkf;k*jjs1t nification distance 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 3* c08n u+toq awph;lhj. 6k:cmq). byt2-2 are in terms of proper 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 would its track be as measured in the lab, on average, ; +ku)c.hw8jl. by* tcpoahq0tqn6m:ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing partb2,e/g t9vm/a/fza g hicle in the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the react t0t1gi9o5igbrbl 9j h*d2-ouion $p + n \to \pi^+ + \pi^-$.

What fraction of the si9yso ; w51dzvpeed of light $c$ is the speed of a 7.0-TeV proton?