Give a reaction between two nucleons, similar to Eq. 32-4, that could produodnpfk *tk -2w* p,)poce a kn ,o*t) *pw kd2opp-f$\pi^0$.

  If a proton is moving at very high speed, so t85,hlkjr82ilbs :(t ak4i ghjhat its kinetic energy is much greater than its rest eh:jigkb5lhas,8 42r8( itkjl nergy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," madao-*-xzkzq kb j1 9z*we up of the antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms,-zx oz*ka1-jb qz kw9* came in contact with our normal world of matter?

What particle in a decay c+q y/up0i54tig lvh*signals the electromagnetic interaction?

Does the presence of a neutrino among the decay products of tf dqv/szv(6- a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explast/-fqvd z(v 6in.

Why is it that a neutro:5xh4 dfpnm/o n decays via the weak interaction even though the neutron and one of its decay products (proton) are strongly inteo5d xn :4mhfp/racting?

Which of the four interactions (strong, electromagnetic, weak, gwksz adyrac4 *2(7hva1 1ur5uravitational) does an electrowc* r7ayra5 zav1 d21hk u(u4sn take part in? A neutrino? A proton?

Check that charge and baryon number are consezp0llac :;i z0pi97q hrved in each of the decays in Table 32-2.a0zli:lq7c ip ph9;z 0

Which of the particle decays in Table 32-2 occurxct9*7y,q x:soch,n;6 lvzyyeu 2 (fqj8 r/l v via the electromagnetic interact2,y e8vq rqcztu xc:s y(9j ol/nv,;lxhy6*7fion?

Which of the particle decays in Tabla (c(0o i.aqg.r9jcf le 32-2 occur by the weak interaction?

By what interaction, and why, doc+t8yfuxm,pn) bzs0ef 8 4;ec es $\Sigma^0$ 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 Tabl.7tf vajjd,d9.km )ree 32-4 occur via the electromagnetic interaction?fevd)k r9 t.jm.aj,7d

Which of the particle decays in Table 32-4 occu qg* te6gxc3z9r 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" th 5z19ow*qf cogat was massless, had no color charge or electrical charge, and did not feel the weak forcco5fz qog9 *w1e. Could you say that this particle even exists?

  Is it possible for a particcee g5jd/o;v.fb8j* fle 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 quantum chromodynamics, wouv+,i9cae. f qjld it be possible to find particles made up of two quarks andf.c,qj+9 aiv e no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when they are inside thqia0r1x *)a.l*,rcbq e: tgqhe nucleusi,g0q.t e:a )a1 cxrl**qqhbr?

  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 p+p cxjr ;:vhy.2g kuurs+ia 1;sks*x .roton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV uzlpvg l-jq6048 v0fqelectrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is usendo .hl 7.ia+ nzk/7ojd in a cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very zf rwo. f.):jyhigh-energy proton in the 1.0-km-radius Fermilab accelerator? w jzoyff:r).. 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 Exaza,jk sit .xow u. l*bl3ca6)-y/qc+a mple 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 nucl; c0xzn --o:u*ca,yyic2gyyxeus: 30-MeV alpha particles or 30-MeV pry 2 c*;o yx0n -:x,uz-ciagyycotons? 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 iqpfrl*hthv 2s-0(lp 5s 55 kV. How many revolutions do protons make to reach a kinetic energy of 25 Met(lqrh v520fhpl *p-s V? $\approx $    $\ \text{revolutions}$

  What is the waveleng.jo g744vfl4wl i5izz 0evcz ,th ($\lambda$, 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 accele7b.) hs1ila ja1tu*nkf rl mf/fxqgj72u63 h8rate 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 lor8 3orsvf- e1uox8lf31 q e2that will be used to house the magnets for the Large Hadron Collr-x 8e f3sf 1ql 1o38oo2relvuider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevoh -+ss.1-qeakpr; hk atron 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 speed of the protons a1s-r.k q-+po; khseh is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of ee 6 y8 1jl2wsobnah71a particle (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 1.0-km-radius Fermcmded,qon: za; e60):7dyo ypilab synchrotron for 1.0-TeV protons? oc :y,m dedey ad06:qn)z7o p; B =    T

  How much energy is released in the f0;cz+csh u v*decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released tqttdt1- m*3 a8r0zlt when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutrejx ;m+j4tzt) on-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particlea5wl -,9ymcw t were the kaon instead of the acwml9-5y, w tpion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. Whbofn a29qsp:u6 5)kj9f xdz-fat minimum kinetic energy must each hav jf qkop9n6 )-2usdzfb5:x9a fe if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must two neu; rfj7, zvk- (pwrm+mitrons each have if they are traveling at the same speed towakrwvmz rjm 7+,p -;i(frd 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 mas 5 aij+5qupvh7ses of the W and Z particles as ab5+q 7havpj ui5out 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 29c,g nwn as*fand antiproton at rest an,asn 9*c2nw gfnihilate? $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 isolated :h j i+e q59rn5l m 0z3lxyhwjq3s+wrsc2u6. eelectron to radiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Beloc+wqhu 3 .:+65e5xeny9lhz ls0s2wr3j jir qmw)?

  What would be the wavelengths of the two photons produce:-yv/gs z (v8tsm2tcld when an electron and a positron, each yvz/-2stgcmvl (8:s twith 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 reactions and decaysoi u-+2e/r cpj8 ytwps;k+(qg are possible? For those forbidden, explain what laws -p eycpsj+(k2oiguwr8/ + ;tqare 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 eachhckp2ynx: s* mxh7m mx4u/*m, of 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 electron in the decayqw5 t 8nw5huv68eaoa+n .iyy 7 $\mu^- \to e^- + \bar{\nu}_e + \nu_\mu$. [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 bge99z -j- eeblifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of thek9: q orq;ek4y $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of:1eh w(k2:saaaua l q5 the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or wa:z0ph u h(n* q 7igng3z):vkuncertainty) 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 possil ll. a1sv1h+pble? For those that are forbidden, explain which laws are violatl 1a.pl1slv+h ed.
(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 ca6txz (encg3(vj+a / mon form (a) a neutron, (b) an antineutron, c e 6+3oavnzxg (m/j(t(c) a $\pi^+$, (d) a $K^-$?

What particles do the following qu)zvc //8 nrcqbt7+v yyark 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 produce *p054hyxn, *t0,wpizi mo,u1z pxzgra $D^+$ 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 ink3 k6q ;rm c+r;zad dk(shh5.w Fig. Below) for the reaction h;d;5 3+h mrwsr ak6.kqk (zcd$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the rjat2wi132wqb8m . v omeaction $n + \nu_\mu \to p + \mu^-$.

  What is the total ener t)k2 qiggzb63wp8)vn gy of a proton whose kinetic energy is 25 GeV? What is its wavelength6 wp)qkt2n38gbgi) vz?
$\approx$    $ \ \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 in rr-h(mks -/luyp1)aito the 1.0-km-radius Fermilab Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do thel hrakprs ) -1u(-im/yy 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 iy )1kf p*q(e/ag,ftgns released when an electron and a positron annihilate each othe()tg1 e , kpnq/agff*yr? $E_{\text{total}}$=    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 reactgx64yz8 w+2ahm pks/;pu(ie 8p9limy ions are possible, and by what interaction could they occur? For those forbidden96(p/4ls mih 8uy pwy +z xa2ei;kg8pm, 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 *:h.orq (ee7os,f.sof ,nd et possible, and by what interaction could they occutrofe. *e7d,.(f:s,s eoqnho r? 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 anr9n326hmiub x:v fj ysf p3tt-+ rq*+opy6p3 $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electro) v)r(mcx(:be 6dde0xm-z+0q z* 7qvewhojuxweak 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 foru *zfq(xm -et:;7 ioym each of the reactions, Eq. 32-4, for producing a pion.tmm :i -yzuqex*o7 ;(f $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the9fk)-ux z 8cg,0yw q(m9ec jpc 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(x txlrdxmj4 un912s* are there in a water molecule?    fermions

  A proton and an antiproton annihilate eadwpq1nmj(c: 1qdz( *ech other at rest and produce two pions, qj m d1 w((pezncq1d*:$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distance ofnm0tf(0/e yr:r./nf i phkv odb7;;kf $10^{-31}\ \text{m}$ 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 Tabprzltoor;* )(pke9 aycg;h 7(le 32-2 are in terms of proper time, measured in a reference frame where th; eor rpo7)z l( a(;9kg*pytche 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 in the follo+ewy g(m6 7 /ow6hmlxnjulpz l;q*c6)wing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model ., k sq2 )xuclla2p(xwto describe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of49 2xh 9vl:z scdejr4k light $c$ is the speed of a 7.0-TeV proton?