Give a reaction between two nucleon+ cy rz+e/dvg,s, similar to Eq. 32-4, that could produce a eg, rv/yd+ cz+$\pi^0$.

  If a proton is moving at very high speed,avky0ysam8 yvdk0588 p/xs /t so that its kinetic energy is much greater than its rest enera05ap/8v0svy/d tyxs8 k m8kygy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticles to the constituents ofvlel:08 ib:jm2 u* lwof)nhk ,u)pd g2 normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with our norma 2g)0m hbku, e)u*nowd8:vj l:i2lfpl l world of matter?

What particle in a decay signals the electromacz+0-o5b5 vv/c z phjbgnetic interaction?

Does the presence of a neutrino am. w-f 1 oacngq+yo/,nmj *dqy s3z5j6xong the decay products of a particle necessarily mean that the decay occdwagmnz.on yq31x jjy,- cs5*o6/+qfurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction even though theqxzme g 2ee4h t-zo456 neutron and one of its decay products (proton) are eg-5hmxtez46 o eq24zstrongly interacting?

Which of the four interactions (strong, electromagnetic, weak, g zy85h10bwb. nwymf+ mel;w*travitational) does an electron take part in? m8h .ywbnbewf5ml+y;0z t1* w A neutrino? A proton?

Check that charge and bary)kle;mxmp a4 kp8,bg -lv)7nj on number are conserved in each of the decays in Table 32-2x mmbvj ep4glk)-ka)78;pn ,l .

Which of the particle decays in Table 32-2 o ( 5edxe9apmb8 ey;3kkccur via the electromagnetic interactx;m 5pb edk(e3eky9a8ion?

Which of the particle de2aas)/6 was -qac3oxgcays in Table 32-2 occur by the weak interaction?

By what interaction, m 3vzo3-19;iil xxjij and 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 electromagnetic inte2+hgjp)5c :oggy .qyeraction?2 g qpe+ogyc.yg)5:jh

Which of the particle delwoo6 t/ysz v*fng1/. cays in Table 32-4 occur by the weak interaction?

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 "neutrinolefe +uhd. vg uq.wg: raz18wxvg/856xjt" that was massless, had no color charge or ewreh1g zq.j fg.u/685+vgx x:vwu 8adlectrical charge, and did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particlo0s./jh..py,jd h* /h(i-hixn 2bcf,w udznoe 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 quantu5 )w+jx b2+n(dgvln h7x auno8m chromodynamics, would it be possible to find particles made up of two quarks and no antiquarks? What about two quarks ang2)nao+( +vd lx8nnuxhb w75jd two antiquarks?

Why do neutrons decay when t (ws*anh1 zc.jhey are free but not when they are inside the nucleu z( cn*w.shja1s?

  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 whose kpxyxa3g ( ogzw. -87(,jljlhx m9em 2yinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength/qtczis/4 k-xns,s uz8*g) mf of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclo2-rc9 db)et0hh)id83j )-orc xcqnxitron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete rels:/uw,swz o txp5 u-.volution for a very high-energy proton in the 1.0-km-radius Fermilab accelerator? T =swt5z/:- .s,xw ulp uo     $ \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 h3 eu)ha*+2gvs3 sune of Example 32-2 accelerated $\alpha$ 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 d2m 7azwnfr6iw/f6c m8etails of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the si68/ma fnwci 6mwz fr27ze of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kV. How8,g6muv r ,.xwj.yjqr many revolutions do protons make tqx.,8juwg ,mvr. rjy 6o reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength v8- 45ah;su*yb-tgj8d9pmh, geierq($\lambda$, 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 a:cf-)empe 50 upy8 myb*. bjgpccelerate 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 kz);v+rj4+r,kfu ben .xwp y,used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic fie,;uwy)+vx br kfe 4rkz ,.n+jpld will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds to br phjc0xjp 2(,jing the energies of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once per turn. Estimate the energy given to the protox2h pj0pj,( jcns 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 (chadk89td;oo*0ese 5 x2pk3mzdqq o;3hfrge $e$) 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 tt ie h4 7r;jzf0hs,v;6 avi;dphe 1.0-km-radius Fermilab synchrotron for 1.0-TeV protons? Bj46fdh avhp ;ie,0isv z;7t; r =    T

  How much energy is releasedt1v/h v np8+ytsaujl6 w4zn4 ,xco7(t in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energ d7t+9jbh:pisjis ju6-m()oi y is released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to 5 5cs6sj nij0- 14sx.kwuk3zpy; huvoproduce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particle/zt j13v sx.*w7gn4optaqnc:tst 2 e3 were the kaon instea to3n3cwpqn4t/: xs*z.j 2a7gtt1 sved of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each othks ;u,oib1n-bl z )ni:er with equal speeds. What minimum kinetic energyu :;)-iok1 nn izb,lsb must each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy jqw2 r:6wlw ;jhgox ha m4ae)m 2/- *p*r2lmbfmust two neutrons each have if they are traveling at t2o)hm;wr*a 2m/j gfh rx*-mpwe:wl b4ql2j6ahe same speed 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 force using Eq. 32-3, given the masses of the W ; s:-kivstgx 6and Z particles as about g ; vs:k-i6xts80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two p zc gpp)(ml81vfbx.l malngg:0+u6estkb,: 7hotons produced when a proton and antiproton at r6upagv:bl8 zlm,pl1 nf0smex )(:7 .b kggtc+est 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 momentum and energy, that it is impossible for an isolatea/hfvgsjlfi.ujlzo7)27d2 q +f7 u5n d electron to radiate only a singlq usa zdn j/f2gl5vhj.7of7f)u+l 7i2e 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 photons produced when an electron and a7, d pbui)+efa positron, each with 420 keV of kinetic energyie, )f ud+pa7b, 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 poss apc -vdl-fmo2(n0 qe*ible? For those forbidden, explain what laws are viola*o 0v q-afnlcpdm2e( -ted.
(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 oznq0lkh4 cwmf(;l 6(vf:t+kz e )wrf; f the two products 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 e (4.rvra cewl:a 8mi8zlectron in 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 estimate the etr+vz(wa) a*iu)bkr 2nergy 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 of the-05a-f7sudwc a(.eeb8k ezro $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of tgzukt1m:1sdzozc f9 -w0. )p lhe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy w7k qu60kmkezudw p 0/bu/c3s 7idth (or 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 that q: p:i*8v dqstare forbidden, explain which lawsqvt:* q8 :sipd 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 *v :p( .0ckizpgusbh3that can form (a) a neutron, (b) an antineutron, (c) ah 0pi :sk3g *uzbvpc.( $\pi^+$, (d) a $K^-$?

What particles do the foye1ua,x wo8i 7q v+udhm2e: -zllowing quark 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* 0j nzl1dgvy)psof:(34b hdu to 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 Feynman8q lj*b.u,*acs9xf vs diagram using quarks (as in Fig. Below) for the reactionxb,98q cj*f.*l svsa u $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram 0g t;9da:qun,7yb+(wuke k d rfor the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of ynwvt3gp(jo7f2,uoo4k* rz3k eii .0 a proton whose kinetic energy is 25 GeV? What is its 7.onpfjoy 3ozik3( iv,*2e rg4 w0uktwavelength?
$\approx$    $ \ \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 intow(o,(guscp54wqc7pzc 5 ijh / the 1.0-km-radius Fermilab Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, hhc(czwjg,wo(csp5i p 745/q u ow 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 released when an electron and a positr;stg ,d(je+tah d :w:jon annihilate each other? ,+t eg;:sdd(t hwj ja:$E_{\text{total}}$=    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 ch5;msx,s5 e*o jr.wy ;z b2kwkould they occur? For those forbidden, explain whyw,r .5x wjszhkey* bms2o5k;;.
(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 possible, and m t6t4-ea7ycjby what interaction could they occur? Fomjc647-a et ytr those forbidden, 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 : ad3ex qx*l7r nprg3v/q4 bk:$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak theory : a6*vy c2g6ozh0guhmh6ct)ph.t m5x 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. 32-4, for sc9 6r d/uyzjbz 2mf d5t5*z0wproducing a pion.2*msyd655 jfzzr/0c zwudbt9 $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for th mzutc;mfjc 5 /il10a./a7btx e 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 ig ,xcw:r l3f7aiockf 9kj8+o; n a water molecule?    fermions

  A proton and an antiproton annihilate each sgp18tk pw,a,98. kx7y i lpscother at rest and produce two pions, yigpslxa8.c1 89 p ,kk7tswp ,$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unifica0bp bnmsc*u* ,tion 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 32-2 are in terms of proper time, me8kzr; wkg.b-d ebbs 48asured in a reference frame where the pa4ekbs.8 r; gbkw8zd-brticle 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, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the following reacttd:*jln)68r c;pui nsions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe ths/ pzsu8c b0erad89t, e reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the spe:*zk *khg b(kc,a7foeed of light $c$ is the speed of a 7.0-TeV proton?