Give a reaction between two nucleons, similar to Eq. 32-4, that could produco;2sfautqje 9 i( f7v7e a oju97 v; 2(feq7fait s$\pi^0$.

  If a proton is moving at very high speed, so that its kinetic energy is m tc0)0 7jnbfjsuch greater than its restfcjsnt)00jb7 energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of tozay5a 86 3apdhe antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in conta aoap3zd8a y56ct with our normal world of matter?

What particle in a decay signals the f,hnnec62sx)electromagnetic interaction?

Does the presence of a neutrino among the decay productap7 *7focg:q is of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via thcigp f77qa o*:e weak interaction produce a neutrino? Explain.

Why is it that a neutron decays v-p qw2ji8va+ via the weak interaction even though the neutron and one of its 2 vw-i+vp 8ajqdecay products (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic,ms44c1qmkx4y3o lrqarf g2 5: weak, gravitational) does an electron take part in? orkcys 5raxmm4fq:lq441 3g2A neutrino? A proton?

Check that charge and baryon number are conserved in each of the decays in T9(dno.o-p kv790 taqukg; o bxable 39kdv.apb qo g-k7x9n;oo0t u( 2-2.

Which of the particle decays in Table 32-2 occur via fra1he*0fef8 .o,cw9;izp :ivp hc9rthe electromagnetic interactif:9ef0pirfpz vch w9 h1 eic,r.a *8;oon?

Which of the particle decays in Table 3 q6nnop6 2y;d,vkl9n e2-2 occur by the weak interaction?

By what interaction, ;6ssyc/ ia-r 5piec0 :)daqqu 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 nb tdjw3: tty.r)r(/vinteraction? 3t t(wjrdyb)r:v. /tn

Which of the particle decays in dmst0a7j.;p rTable 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 "neut3ah9 pjfbj9m -csz6k3 rinolet" that was massless, had no color charge or electrical charge, and did np 6jmcj9a f39z h-ks3bot feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to b+nx c/q(kf5 le1;df ghe 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 quantugzi fkb+n 1tcah8kn89 ofcr2;rn7v) kfg79j 8 m chromodynamics, would it be possible to find particles made up gf cac+r g2t8 n jkhnvfn98o8f7)kk9; z17ibrof two quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but notzrqmlq 054 (q+gvz 3bgf(1r 4usji n-q when they are inside the nucleugfm-zulz4 i+ 0b(v5j qrqg(3nq q41r ss?

  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 whod bhczgsxq-h6b 11b1msls86* :+pg1viid + grse kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-G es 23hmsh.0 qzi2;1orejjv,:s6do cpeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron iu,ko6+xy m/ d 4iji.fqn 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 9wte+q;bc(6w6g rbrj-energy proton in the 1.0-km-radius Fermilab accelerat+ecbr 6 9bw ;tqwr6gj(or? 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 8 -yrn2xf1ep6av, ef5 t* ajaxaccelerated $\alpha$ 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 pickinp0 tjj4 twjbj dt/d3-:g out details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of pt w jt4bjj d:3djt-/0their 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 55fodmnt0.*k7x0kc w ojxof) -90ijv*j kV. How many revolutions do protons make to reach* ctjoi.) w xoj *9fd0mn0-k0o7 fkjxv a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (airz gy1.xc4an/z: +l $\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius ofmkm,*z ;u )r*zj jtkwn ke,bz7*:dl 0w 1.0 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 tunne7br/ pp )0uxfe.,f1xo rarmy3;iod3q l that will be used to house the magnets for the Large Hadron Collider (LHC) calls for proton beam/o03fd1xfbmq.op, e ;7riy p3r)rx au s of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermi)m qyfndg.2j 2lab Tevatron takes about 20 seconds 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 protons on each turn. (You can assume that the m2nj .dy)qg2f speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a partivww;f4zsmy2qlcfz44 *a u ,* ucle (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 1usgmo9n0zjq2 9oj91h .0-km-radius Fermilab synchrotron for 1.0-TeV q0go n1jhmzju29so99protons? B =    T

  How much energy is released in thefdgzxlofgci6 szzdf8p9(:6, jm0 , 2 e decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is release pg5;5vwaz vh4d when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is requir rcgx,k7.o z34v91,w yownshned to produce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the media knd +4lwkx:s3/ukq:q ting particle were the kaon instead of the pion. 3wl:dsk4:k+/qkuqx n $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading tzaoq5n7yn), ss bsyfet pn,, ), gf5+moward each other with equal speeds. What minimum kinetic energy must each hzf+sp,nm,7gbs no5y ,s e,tnfaq )y5)ave if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must two neutronht(p28iufs1m*o5 (v7gh x ygcs each have if they are traveling at the same speed to *1g5i stf(x8ygpo7hmh2 v c(uward 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 ebt b2zi. ;n.xs frcz /k-tbp4t+s+s 3of the W and Z particles as about 8s2; 3 it +k- rpfn.4.zsbtb+xz/ cetbs0 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 antiproi sv87x2ta2n otos282n a ixt7ovn at rest 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 isolat *lp1e x/i.nhted electron to radiate only a single photon. (b) With this resuin1phe*l/ x. tlt in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produced when ;sbu9y;zyxh* q+v kkt(,-pl jan electron and a positron, each with 420 keV of kinetic energy,px+vlkq;z - ,t;uj yksh(*b9 y 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 i +e ek2amxfp4;j7t-p71gfnbreactions and decays are possible? For those forbidden, explain what laws are vi e-j17kntf7mfa pp x;i24g+ebolated.
(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 pr-x fg p.*l;bvrmwi8;aoducts 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 kine., ypsnmjzv e.p7;15oi5foo yo(ljo7 tic energy of the electron 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 ajo cg,6bs: th+f/ m;ugnd 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 thtx5kfv 9i58 uve $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the*a ;v+,wqp kmr $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width b msch6k q82( 1tdkqk)n.n1oq(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 tn brsx fn,u;f3 +xf n6vg,9lu-hose that are forbidden, explain which n -nsnfxuglb69v;ffx,r u3 +,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 combi cvw :y*i)nun6nations that can form (a) a neutron, (b) an antineutron, (c) a )vn:cn 6*y wiu$\pi^+$, (d) a $K^-$?

What particles do the following quark combinat5 ,8yluan3l 3fncy 4hcions produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combinationwqw9t0v+tx/ w4zv(o lo.um( l 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 using quarks (as in Fig. Below) for the rea1+opol +il6k j ,od/u kk kjd,b*rsy6+ction kjbrp l,jyd+dkoo, 6s/o 1+ lk*ik+u6 $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram,gr8wb e2tj l8v6k -car)x /tm for the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a protld dz4e 6,z reu).5jwmon whose kinetic energy is 25 GeV? What is its wavelength? r ue6e)54d,lj wmzzd.
$\approx$    $ \ \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 th 3wus sf)+::nlkgt8n we 1.0-km-radius Fermilab Tevatron with an energy of 1gsnl::fs3 )wk+wu tn850 GeV. If they 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 released when an electron and a pott,tizy11a5m9j d3c0x y hzo1bdu74 ksitron annihilate each othero5ti j7u1 ycbm41t1z da0t,hd 3y 9zxk? $E_{\text{total}}$=    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 i0c*kmqc 1)dlte9 nu1bnteraction could they occur? For those forbidden, explain why. 9d cu)0q t ke*1clbn1m
(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 icfqrw wevg j+m(fue nndv1 +n 6e+0);(nteraction could they occur? For tmcdew(;++er w6 qn)ugvnfn (+1ejvf0hose 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 aew/ux. m)/nf 2fytve7 a.8vhi $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occulx3w2 q wkx9qotd,3 8zrs in the 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. 32-4, for pwndp ,1dpnor :(oi (m2roducing a pion. 2nw(1n(p idmd o:r ,op $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for t nj(3 n(,qvlu: ;qk;avsyj dm8he 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 a r 3/oj7mmk)oq water molecule?    fermions

  A proton and an antiproton annihilate each othe+xt;rm4xd kp h7j a56ir at rest and produce two pions, 4ixj;h75+ardk xp6t m $\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification diga-h77odz2 im stance 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 timex )kbbwc8yq3k- j15wkhv 3/b enuhx(1, measured in a reference frame where the particle is at rest. If a tau lepton is created with a kinetic energy ofkkeu-33)bv/h8n wxx ch(15 y1 qkwbbj 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 rp -68;dyyju d6thc4d6wnnq* neactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the reactiotg w6-p1q tli)n $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of - 4iod3tme 5rylight $c$ is the speed of a 7.0-TeV proton?