Give a reaction between two nucleons, similar to Eq. 32-4, that could a3air +cc.3zhproduce a +i3ahr zc. ca3$\pi^0$.

  If a proton is moving at very hi0mq5gyn.5esbd o(/cqgh speed, so that its kinetic energy is much greater tha5by 50coqdqen/(msg .n 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 antiparttuv v3kk9: n.iicles to the constituents of normal atoms, consist of? What might happen if ant.i9 k :vunktv3imatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic interams(( dv1q2np8xv3,jrxe/bh e ction?

Does the presence of a n5mqh6vham -la, 0(vbbeutrino among the decay products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak intb(mhvl0qb-a, 6a 5vmheraction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction ev 0m5fla q/obt6 0xz7uaen though the neutron and one of its decay products (proton) are strongly interac5tazbm6 qa/07lux0 o fting?

Which of the four interactions (strong, electromagne; jiat n2*q; cvpj + u4x-s0lc.nl-lmitic, weak, gravitational) does an electron take part in? A neutrino? A proto jpalm+l0; qv- -c ;ui*n4 tslxnjic2.n?

Check that charge and baryon number are conserved in each of the decays bij-0g3 em zj/in Table 32-2 /g j30bmjiz-e.

Which of the particle decays in Table 32-2 occur via the el:xq /zr43ss :subzsr.ectromagnetic interactionzs:zss 3r/usbq.x4 r:?

Which of the particle decgo24g8 ) 9+q *rqwbfg cme+sfjays in Table 32-2 occur by the weak interaction?

By what interaction, and why, does *xuml i+la + s8cws5bp.d-c7v$\Sigma^0$ 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 y.xgzkqve7v8z1xz gx37v *p;in Table 32-4 occur via the electromagnetic interaction7vz.e z v gx3x*8 7yzp1gxkv;q?

Which of the particle decays in 89 ujji sx+v f):o2gzyTable 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 noyfnpm w-uu6f6z7n d 6dw9lv5/ color charge or electrical charge, and did not feel the weak force. Coul/p 5f6yw-n v9uz6 m7fd6udlwn d you say that this particle even exists?

  Is it possible for a particle to be bo : qmyj8nm8vs;bry :di 2l8uz)th
(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 possibvtcn1. p,fsa(le to find particles made ut.a f,(v1cspnp of two quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not wjkx djj zx*cv34w( y0(hen they are inside the nucleus* z(v(0xkjd4xj3cjwy?

  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 ene4(jax i*lg o4xrgy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV elect2qo0/ft aau18gn(jsw rons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyc7e6mdf xih.9 tw1*gtplotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a ve0 gr9q4-0ffu:a 7r beviopq; ary high-energy proton in the 1.0-km-rq-o ;prvaif0a4rq: g9u7fbe0adius 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 cyclotronfr2 xkeg j v b(++h bc;*j,rq,l+:byjj 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 details of the nsp1ndp z/0zj:zsz / i1ucleus: 30-MeV alpha particles or 30izspzd/1z:ps j 1zn0/-MeV protons? Compare each of 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 myja21* nhib a *m:0zglany revolutions do protons make to reach a knb*z1 *0hj:a2 imaylg inetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength 9 0obgkoe8rp4x1lmec t8- i*u($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m is u9 nh)30 lpttq wa,ks2to 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 tunnel that wi:)b,gf8rm au:8ekhi x( hd6 lill be used to house the magnets for the Large Hadron Collider (LHC)b :6x8 khi,h)urm (l:g8efida 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 seconat u)ktp)wpe-3sm pd;k4*stq : sn1 .sds to bring 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 protou1 tks. -)pktp* :3 tandw;pesssq4 m)ns 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 (ch4z3bjqa2mm (+msa 0 pbarge $e$) 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 bfd8;.pdil r+needed at the 1.0-km-radius Fermilab synchrotrobp.ir +; 8ddfln for 1.0-TeV protons? B =    T

  How much energy is released in t ut2d+5:z ocrl (qn5jnhe decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is,b+xko62ob pn released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron 5j8k nrl,o;c 8*ujvnmpair?    MeV

  Estimate the range of the strong force if the mediating particle were thi-kf 6 ipibau .dq0/eu9z:s mgv 4,q5ye kaon instead of the pion. i-q szmfi9 u4ikpue5/vg :b yd ,q.a06 $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other + n0t klg(a5o vi8pis-with equal speeds. What minimum kinetic energy must each have pks +tg(-5volini8 a 0if 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 v)t rd7uu.vh9yx:o8d5 jb8 fr are traveling at the same speed toward each other, collide, a9otd 57 rrvv8. d:)b8hyfujuxnd produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak f 7yrb:yt+e hb5orce using Eq. 32-3, given the masses of the W and Z particly5 b:r +ebhyt7es 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 j: vx( xtyc5;iwhen a proton and antiproton at rexv jxtc(;5 iy:st 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 imh,se n9zsh .;solated electron to radiate only a single photon. (b) With this result in mind, how can you defend the photon excez9 n,shh.s m;hange diagram in (Fig. Below)?

  What would be the wavelengths o1aqa +pdcvpi5ih0* 2fyl ov- 2f the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihila2d ifoa1c20vy *v-ph iqpl +a5te 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 reactioneo4n -t7saj /vo(6 ls5pn sr)js and decays are possible? For those forbidden, explain what laws are vio opo6trvjs js)n- /e nl74a5s(lated.
(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 dldtbhy a97 g721 9(rklbnu( jpecay $\Xi^- \to \Lambda^0 + \pi^-$. 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 nij0h)8ar*;q(9-uyzab mxiu 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 andhp :ex*gt xss2a ;z:d.0o/p ay 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 th*-se xmh1 8waee $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of t p otg*8l.ym9yf;is0mhe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or unce.;w58h pnp srzrtainty) 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 dg9+y)npuj wj(ecays are possible? For those that are forbidden, explain which laws are violap)n( jju9gw+yted.
(a) $\Xi^0 \to \Sigma^+ + \pi^-$
(b) $\Omega^- \to \Sigma^+ + \pi^- + \nu$
(c) $\Sigma^0 \to \Delta^0 + \gamma + \gamma$

What are the quark combinatio5kv9r:5gw0;j el k*ep va p9+l;xphhons that can form (a) a neutron, (b) an antineutron, (c) a 9;x 5 hpkwe5+v9 *ljrkg;lpa:epo0h v$\pi^+$, (d) a $K^-$?

What particles do the following,w:exqg :fxu 89kv .dr 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 thtcfb+l0 hku3a( ;a*s- p:w qbo 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 using quarks (as in Fig. Below) for the rew (s/hmwocs((c3vr y 8action(w ochssm/w(3 vcyr8 ( $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram forr /ku1d9s1xeasj9 2 jj the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV?lm)8kkf6m ae3lmtq1- ry d u-2* tzg,e What is its wavety3d1ka 2g6 lz-,m-rme)qf me*kt8 ul length?
$\approx$    $ \ \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.yvrfb x*s1 *y40-km-radius Fermilab 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 lx bsfv4ry*1*yong 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 andx )ni3iy ob-(u a positron annihilate each other-o )(nxb iy3iu? $E_{\text{total}}$=    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 interactio5iaql,ur1i1l: 5ylog n could they occur? For those forbiddel1 q y,l1laouir5:ig 5n, 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 possible, and by what interaction could th ) 2xtsbi/l8n,1b4 mbcf tnb:iey o:ltn8 nt/c 2i4bbbmb fs, 1ix)ccur? 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 /clrnbustu*9ko3j0)h; o, fk $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in tcjihmf83wf) 8he 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 reactions, Eq. 3266bnn b,gt8 nx-4, for producing a pion. bnb6 ,gn6x8tn $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reactvd)b h.9g,v*l9 uyo+pd k -oqpion $\pi^- + p \to \Lambda^0 + K^0$ 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 a+k9sbufu6-y9j1 vn+ 6rpof csre there in a water molecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two pions ateeio(j*-:kh,a5d o , detjhae5 (a,*-o:oik $\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distanceyxdi s+7b4n 7c 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 -szfnysu vo64k/4k 7e in Table 32-2 are in terms of proper time, measured in a reference framekvsf4 k 4n/uey-s67oz 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, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle ,ud( bv-r.voj3 wm2zvin the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to descn4pydczm; n. rd0:9cl6 byws8ribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of ligf 3f(blx;4kqt2y6bob b. upm(ht $c$ is the speed of a 7.0-TeV proton?