Give a reaction between two nucleons, sj ce9 83 6pjub+pz)bjcimilar to Eq. 32-4, that could produce a pbpcj )9 jb6zuc+ej38$\pi^0$.

  If a proton is moving at very hightzm1n)fi /()s2q4 ciswkk f4g speed, so that its kinetic energy is much greaf 4k)qi(k sis f wz2n/g)41cmtter than 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 antiparticles to the constituecx/t zl+b7k(ents of normacb(zt/7kex l +l 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 signals the electromagnetic interactionmj ,(y;a i8my/wy9-s bs3c :gvm5cbr r?

Does the presence of a p+, /sirmmog( neutrino among the decay products of a particle necessarily mean that the decay occurs opg +m/ms( ,rivia 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 toqzv*hrx0 2 z fo68dy0he neutron and one of izvxqo0df*0y8r2 oz 6hts decay products (proton) are strongly interacting?

Which of the four interactionsu9vg4g m1cm*n.v 9z td (strong, electromagnetic, weak, gravitational) does an electron take part in? A neutrino? A protouvm 9t g*9zc1. nvg4dmn?

Check that charge and baryon number are conserved in y-* dns wip6hb82y rcs3ya 7t;p**suj each of the decays in Table 32-2.pauss nb6;8 3pw-tr2hy*id*cs*7jyy

Which of the particle decays in Table 32-2 occur via the electromagnetic interacvc b6u1f ho(:opx/c(itj +twe r7d97athc 1r(+o (f7pb79dwa e :uotc6j vitx/ion?

Which of the particle decays in Table 32-2 occurz*q* zr7fe4qlu)m0 hk,l)ztn by the weak interaction?

By what interaction, and why, does 9w(skxbq ,m*(p sn bd/$\Sigma^0$ 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 in2f.s kp57xzff Table 32-4 occur via the electromagnetic interactisz57.f2 k ffxpon?

Which of the particle decays in Table 32-4 gl8bg 8tqg)d.+)cw tb 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 "zm7k 8j) nn7h o8c7uf *dvxxv)neutrinolet" that was massless, had no color charge or electrical charge, and diuho 7nm8 k87x )v)*cfdzjv xn7d not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to i)js(6yv dmjps 7: l.zbe 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 poson82ubc( u ns.sible to find particles made up of two quarks and no antiquarks? What about two qua.uu8s(2n nobc rks and two antiquarks?

Why do neutrons decay when they are free but not when they are +ygwc2zm(y -z inside the nucleus?y+yc-g 2( mwzz

  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? zvg/n7 ec6l ,)-g yluq    GeV

  Calculate the wavelength degd 5ila/s,65jsu;x of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protons make0*9b/pgo5ka 3qrhk7 xc qsyj7 $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very high-energy proton ;y- mg0 e/)rfva1pwhu5 . pkclin the 1.0-km-radius F pc)lha/5m.w0ug-re yv 1k;p 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 xv+)0r wheid (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 nucleus: 30-MeV alpha particles opj g ukyv.t8; 5tq,gl9r 30-MeV protons? Compare each of their wavelengths with the tly5vtpuqg9 ,. j ;8kgsize of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 jd+ow3 n-tx h8lqmm (9kV. How many revolutions do protons make to reach a kinetic energd3 m h(9m8lotqwxn+ -jy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (ud3:71m:0 jo:rd jvdjh 5hqp: n rzta9$\lambda$, 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 accelerate deuterons (qm6s,;dkg .sslu/(ah$^2\text{H}$, 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 magnrxv/imx0d, f;ets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0dx0; imr f/,xv TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Ferl9a(8 j 01ailon4d z *ckkhz6omilab Tevatron takes about 20 seconds to bring the energies of the stored protons from 150 GeV to 1.0 TeV. Tjzlo1ho*iad 0ca 8nl694 (kkz he 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 particle (char z(c14x p7m 7/9yzk jmqq opj;.sbjad4ge $e$) 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 asq-v-u.)l7jbqo nom; t the 1.0-km-radius Fermilab synchrotron foqm )bo l;jv-u-qosn 7.r 1.0-TeV protons? B =    T

  How much energy is released in thejx x3 ktx:tjgny ip1u w-8y*z );o7py; decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is renpjkxd1 r0h8+4 wl i3 iwksv1(leased when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron pair?/arsk 9 7on ha9xw(wtunvo-2 0    MeV

  Estimate the range of the strong force if thet 7g/i2qac/sucej w/1j.ok7*1h ndmt mediating particle were the kaon instead 2/ 7gsnta c e.q/jihdkw t7 *j1u1o/mcof the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading towfhdb-i5o 1 mg8ard each other with equal speeds. What minimum kinetic energy must f -8g 1boih5dmeach 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 they are traveling y :o/qokr6sok6 a)a8*1x rnlaat the same speed toward each other, collide, and produce a kar* 6 a:ola8knrs o1xo6/ yq)$\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using 9qaedg* ;zqe(Eq. 32-3, given the masses of the W aq e(dez9;q*a gnd 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 antipei3jo f*j9 ws:ji) l1jroton at r:1s3jj9jji loei *fw) 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+i9gw l smp0x1xt1q jb;u 4v7d, that 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 exchax;q4lw1gp0 tvi u71m sdjx 9b+nge diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produced when an electjgbrrf6*n :5c*t+lt)q: ut hxron and a positron, ):g*t+n lrujbc tq 6 r5xt*f:heach with 420 keV of 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 reactionshwwd 0nq-s-01gfd 7vsf1i/gl and decays are possible? For those forbidden, ei1v1 -whsg/lndf0- sq0gd7 wfxplain what laws are 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 do1f5 bfa 7vcuvuj;,5mecay $\Xi^- \to \Lambda^0 + \pi^-$. 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( .r4 m +bchbazcbqvz+y/: 8mt 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 zrypbc7) 7;(t db+wrlenergy 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 ofn2q;d3j n1/po wqw cr7 the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the) i3j d unissg ef27f,xq3/6ab $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy wi8kf ele 4rzu agkj9ulf.zc 92x(7v 1g)dth (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 are forbidden, exply*.ooqw dv :f 67lum5wain which laws are viol5odvq:uy .*lw 7 omwf6ated.
(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 form (aap1 ovyi by)/0) a neutron, (b) an antineutron, (c)ya bv1/o)p 0yi a $\pi^+$, (d) a $K^-$?

What particles do the following quas5.8:jd ; j6ttzzpl dj )lz2dark 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 to producjnu37) ,kp zjmu7)6twbd vah+ e 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 re ccik6/bg(t i*action(tkgciic 6/*b $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram f o9 p 3wux/ zp0hy38s0abc5ywlud+j/5 3gmhna or the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy i9m)x8vto knvmdt j,h)g; :l8 fs 25 GeV? What is its w8hnjfmt)k x,l9vodg m: )t8v ;avelength?
$\approx$    $ \ \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 an e) 7aqxjg)m(n:j gd5(*(zfw a vvmu sg5nergy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and approximately how long does it take for t5nug( ) *vvfz 5(s gm ag)j:dxqjmw(a7hem to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is h:f ru2 xnc4sn/ *-ymhreleased when an electron and a positron annihilate each oty-/hc:* xn2rhmf 4 usnher? $E_{\text{total}}$=    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, and6gh gt )z+ ok +kj-90h exj/iztcn3w5u by what interaction could they occur? For those for jin)-t5gtkjcw9e 3hgz+h0 zkx6u o/+bidden, 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 reactiotxhp1.i1:(esawi vf*:yjn )cr. - qdvns are possible, and by what interaction could they occur? For thosirqd a*ph:.v-1iws1cf(ny .:je )vxte 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 afbo63zvu ;c 7w $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking ocimm-auj67x-lg /f ja7v f13j jcurs 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 prodw/y1pp 1a*8h 9dj2jdi/boj 6kj 9avqvucing a pion. 1/ /pdjh1989j ijwy vq*a vb6 adj2kop$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for t byqw70p7 ophttrzd9 dv .n ,;m/k(wo2he 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 fe5l-4xsioxk/8 aonho n:)l zx;rmions are there in a water molecule?    fermions

  A proton and an antiproton8 z nk zorv,.sgnh 4zlmk;,5dj0l:kppoq6-3x annihilate each other at rest and produce two pions, klhq xk4prn z:,;vz dljo5,-0o gzm8 3.s6npk $\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unificatiofvz1x,/xguhkj +uem 2;c; ,ta n 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, mean z5v8l/8bvuu7x :g8m jon6ypsured in a reference frame where the particle i:l8pmv6ygu 8o/5b uzn7nv x8 js 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 foazekcr99vz3 w1y1 3 e / 9mxcew1zmxa0llowing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the;mx71 .(c)hrz ,8v)x xpdpqjuc+s zvm reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of b pkg;obnqf/-n:a5i q0 3 w43mzsv c-wlight $c$ is the speed of a 7.0-TeV proton?