Give a reaction between two nucleons, similar to Eq. 32-4, that could pro.tt ej5)mhv6g 0)wqk irjp7(e duce a mw.)7j(g6 vth )tekj0eqri5p$\pi^0$.

  If a proton is moving at very high speed, so tk.5o*fg3yp: tfu t4aiby;5 pthat its kinetic energy is much greater y *pkg.;: p iayttu4fto5 fb35than its rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the a(1r4 n2 vs7m8i ,hf2n)pwnjerljevv 4ntiparticles to the constituents of norm2rpsj)vfvmn v 4 ,en4287wr ijel(n h1al atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signalsl9 h(p8nj4mmz8tc,wg the electromagnetic interaction?

Does the presence of a neuw6taa.a.7zn: a3lkk ytrino among the decay products of a particle necessarily mean that the decay occurs any az.63. tkk7:awa lvia the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak intcdxt9m,s5z i bd1* 3aueraction even though the neutron and one of its decay pd3,bc z 951sad* muitxroducts (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, grs65b+jnmz5y k avitational) does an electron take6b 5ym +zk5njs part in? A neutrino? A proton?

Check that charge and baryon number are conserved in cg c*ukyvki:.-a)l -eo)nr 1p2xl dh3each of the decays in Table 32c e3ladv o rckyxngui:-h1.* ))p2-lk-2.

Which of the particle decays in Table 32-2 occur via the eleg c+8b7lc* esqctromagnetic interactiocg + qe8clb*s7n?

Which of the particle decays in Table 32-2 occur by the weak iy6 ny7ttwzz ,8nteraction?

By what interaction, and why,3y- -k,xw gxhz 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 via6awwepe d)1 0h the electromagnetic interaca0h e pwwd)61etion?

Which of the particle decays inp yegu73xy 3,28zc v .f*ltd,nqmf,dk 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 "neutrinolet" that was massless, had no color chargjg6k3dsr o ba2cnwg7 +p2z4u.e or electrical charge, and did not feel the weak force. Could you say that this particle even exists?n722 b64r.o cwgg3jkpusaz+ d

  Is it possible for a particle to be h*kiz2*.*jh cby :vwoboth
(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 possible n-n2rzev,.lh ol, v2k to find particles made up of two quarks and no antiquarks? What nel .2 2-o,l vk,vhznrabout two quarks and two antiquarks?

Why do neutrons decay when they are free but not when they are inside n 6ji + 5vld9gio/yuc2the nucleusn dyl2 jgi9/5ovu +c6i?

  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 kinetic energy is 6.35 GeV? 3gutihq-h**df6 9ey8qgz k m:    GeV

  Calculate the wavelength of 35-GeV el m0cncb*r )s)qectrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotronm/o)d7wh ynlsi*iv7/l e 4r )q in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution fo +)ex6j kk 3iv,fs:lev c7cn+lr a very high-energy proton in the 1.0-km-rcn3fx,v :k+ve7k6+ci jl ls)eadius 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 accelerate3q6pwour uf-2pe *tn)d $\alpha$ 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: 30-MeV alph ardd23*2uq7nkx ):c/ ts qiepa particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleoutpn:*2x)7as kqicr/dd e 2 q3n in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of b4bl mnv8cy- +a cyclotron is 55 kV. How many revolutions do protons make to reach a kin-yl+vbnmcb 84 etic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength pe3a hp)sbdko(lq*/d.g2v9 x($\lambda$, 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 accelerat0,t v u2z(ahwta nr.s7e 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 for the Lau xyf30iutg c6p+3, :bscw m4urge Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B ,xu:bsg cw 4tpi03 um3c+yuf6 =    T

  The 1.0-km radius Fermilab Tevatron takes abib lbm:uiqm/zw-n87 ;1 bxv* sout 20 seconds to bring the energies of the stored prot us:z m-ix8wnbb l1 q/bv7mi*;ons from 150 GeV to 1.0 TeV. The acceleration is 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 partic ofpg6pf,fhh2na)d4q6 a zv xq2;69dhle (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 l hx -53 hp4fpt(r t4xkdp 6.dyenb-3bthe 1.0-km-radius Fermilab synchrotron for 1.0-x(p353 yepdbld r4hhf kp-t .nb6t-4xTeV protons? B =    T

  How much energy is released in the o 4lxb9las0wp0/eknwn39u ; adecay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy li lf5bly4)y+ 7tg7 6b tu8r(aaw8yxcis released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a ne zv9kg)rukk(5 utron-antineutron pair?    MeV

  Estimate the range of the strongpt7d 7p)s9 tyc force if the mediating particle were the kaon inst yctp7p)7 ds9tead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal sp5nb mtmnvjz;t+dasb4*/4 it/ eeds. What minimum kinetic eners b/ni tz *tmv5m d;+4ab4jt/ngy 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 e5 am i6gkjpd d61db96yjx0l+mto5st8ach have if they are traveling at the same speejdd8b66iy mx pkt51 sdag9 6o5mtlj+0d 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. 32-3f)7 3jwxmbl,d , given the masses of the W and Z particles as aboutj3 wf7)m,xd lb 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 an*gw/-u7xnw) rd+(g(qdpiq z r tiproton at rest annwdgr7 id(zgwn)qxpru+/q*(- ihilate? $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 isolatei9p5- ljdi6+aa ey6x5 f f8zwrd electroi ixrfp+el yfa 6zd5a-j56w8 9n to radiate 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 photons produced when an electspc99* ot1qp .e-oik rron and a positron, each with 420 keV *-s9ret 1pi.p co 9oqkof 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 cu53h7;wt nyv lzp99ddecays are possible? For those forbidden, explain what laws aren y5;vw9t uhclp3 97dz 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 in the decafitz;6-(q x; rsk.t rqy $\Xi^- \to \Lambda^0 + \pi^-$. 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 electop* oo,z: 1w2n//ka8y yi xnvdron 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 energy width and then the lifetime ofo k.dpt 3- x g,mh,hr-jya9dq6 the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of ta5ynk gfs req7( z8/3l:j) qwmnrv74yhe $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of -7 oi9n lwo:qj:+jogtthe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertaintcrb5n-r f g0q. q4y80 u3otygqy) 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 den+lib8 ). p9ru5vom2z2z lwemcays are possible? For those that are forbidden, explain which laws are violated.m8zr 5 z2 u.)2mle +vp9inwbol
(a) $\Xi^0 \to \Sigma^+ + \pi^-$
(b) $\Omega^- \to \Sigma^+ + \pi^- + \nu$
(c) $\Sigma^0 \to \Delta^0 + \gamma + \gamma$

What are the quark com h4: lrbzg1 mf0bg9dxi 6./ y5hjakd+obinations that can form (a) a neutron, (b) an antineutron, (c) azr4f1.ij5 dy +gk:gm/d9 bhb6 xhlo0a $\pi^+$, (d) a $K^-$?

What particles do the.:fi)f*h4brnyz uyf0 following 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 combinationnniv/e.gyv;i je706 y needed 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 Feynman diagram usin9zy3e yts+m6cx+twj; g quarks (as in Fig. Below) for the reaction+ z93 mj;tx s6wcyet+y $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram fesvj31*ak,w of* :kb z zj+d1.clwr +por the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy isyj3*l7 k3svb5.riz t w 25 GeV? What is itswjvzrkb 53*sil7 3t.y wavelength?
$\approx$    $ \ \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 with anp1;cij-l+pg w3co5 sjp/ae ) xig :vz8k)a;nn energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, hp)xa o1aig3k+nncwe;8-i :pj/g)j s; 5pclzvow 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 posz l q813)mt;nqi ) 5zsoafsyg8rz2+bn itron annihilate each other?f+o2bg )i8m3; ) 1 s85zysartzqln qnz $E_{\text{total}}$=    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)nt ca:)-pjpp7i(ik cy kjz4- are possible, and by what interaction could they occur? For those forbidden, explain wc7aij z4pitk)p( :c ypk)n-j-hy.
(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 by what interaction could tyn+o8m cz33 uvhey occuv+ym38 nu3zo cr? For 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 8 (dbls*v8bb7 e5boou$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the elec-b2ka6wgtn -xd55vzml jm7m z( xk*9 ltroweak 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 reactiodw q/. 1v8lh2 k1 18ilueznmgnns, Eq. 32-4, for producing a pion.hm8/nw1e q1vd8 2glnklz1iu . $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reactiodt )k.jkap1e,3e+ bivn $\pi^- + p \to \Lambda^0 + K^0$ 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 molecule? fxlu: a2u.1dhmw 9d; s   fermions

  A proton and an antiproton annihilate each othegwuj* u,33nq8a ,7n ltt)bln gr at rest and produce two pions, jt8t uw*7l l q,3), na3nubngg$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unnk0wh/ c gtbpgg6u 3.h.4w6vbification 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, measured in a ww8:nqi.c n- breference frame where the particl.n ic8nwwbq-:e 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 tl sm)z-l*ozf2he following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the reactio: nw8hjh*4zy l xtc-k3ifs0 c:k akj98n $p + n \to \pi^+ + \pi^-$.

What fraction of thesx wac8l il:-/ speed of light $c$ is the speed of a 7.0-TeV proton?