Give a reaction between two nucleons, similar to Eq. 32-4, that c e jsif9//3mg0w4hub pould produce a fipjgse u/9hwm03b4/$\pi^0$.

  If a proton is moving at very high speed, so t1j ,xbi4n61vm0r-1) wusjz w(cobym c hat its kinetic energy is much greater t 1wjb6nm4m0cwz u(jc-)r1by1 vi,s xohan 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 ah ro -t.d/nix*ntiparticles to the constituents of normal atoms, consist i /- xtr.onhd*of? What might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay w y eb0;:dz3njsignals the electromagnetic interaction?

Does the presence of a neutrino amongk -/huwiv0a g kc5wy5 qlt(69v the decay products of a particle necessarily mean that the decay5 -05ak / cw9thvkivq(lg 6uwy occurs via 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 the gk+0fvy:18q*wpr rat m d,;fcu f(:yh neutronuhtr 8fay,*mfw 0q;1:grv+d:ycf p (k and one of its decay products (proton) are strongly interacting?

Which of the four interactions (strong, el(qww( 3-b/wuw+f)dnw xz9 rvyectromagnetic, weak, gravitational) does an electron take (+vw zur 3xww fwd q()y9/w-nbpart in? A neutrino? A proton?

Check that charge and u0wmk3-4 u+ j*ffsiqs 7az+zhbaryon number are conserved in each of the decays in Table 32-z* zk7h i-3w4msjfu++s 0afqu2.

Which of the particle decays in Table 32-2 occur via the elkcwyg.l3ns -6 l5c *kiectromagnetic interacnc5*g kylkswc. i3 -6ltion?

Which of the particle decays in Table 32-2 u c2t 0ff2(f vkhub5f8occur by the weak interaction?

By what interaction, and why, uy git:i pvk2w 7gi7,gq;4qm2(zj y4vdoes $\Sigma^0$ 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 electromagne8o3g3upp lg:q3 hrqrktd8 :y4tic interactionrug p3k:tdp :qg84h3 lq ryo38?

Which of the particle h (1p61+mcch s(zehelo3k:vm decays in 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" uq b z-b)1is4hthat was massless, had no color charge or electrical charge, and did not feel the weak force. Couldu-ibq 14z )sbh you say that this particle even exists?

  Is it possible for a particle to be bothf1;2y . uz/*mlhjsq 9extqcf +
(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 qu 7t5: 9xhimpsugh,f-d antum chromodynamics, would it be possible to find particles made up of two quarks and no antiquarks? What about two quarks andp,u57s:hg9i mt fx -hd two antiquarks?

Why do neutrons decay whem,0so:,onc kw(qfccz9 ds 2r9n they are free but not when they are inside the nucleus?9c,(,nm:zrc ofo0dq 2k 9s csw

  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 l;qw:paiu;s;jq0ssy ( w6k k/proton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelenmoh1 (b8yhc mj,a)w o/gth of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protons s8eb. (zjn+ejzn , oqj; so,8rmake $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very high-energy proton (wnb8r f 6myy3md.a u6nnj j4. z1hu fet)83ouin the 1.0-km-radius Fermilab n)j yu z8ue.(6om4ubf rd.tnm3 afh36ny8w1j 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 32-2p7 a8zb3jr 0e0c sds/z 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 ywn;1/zzx -hroe8b h-details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleon in a nbw- y;znrzx -h18h/ oeucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 5r(pmjdc2vh ;ua l 1(+d5 kV. How many revolutions do protons make to lar(d;vd2mjhu+ cp(1reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengthxwbk;gao92 sl fj6suo 38v )2rcws1 q) ($\lambda$, 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 acceleratyu7o wfw0 4xi2nkj+; z;zuz:ce 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 tunr+o 8cwl.i j b*zm2my,nel that will be used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? lcr z,y.8ij wob2+m*mB =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 s: *c5eqp x(rwic-c+p)l skc1qeconds 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. (Yo-rckx:i scc +qp*pec)( 1lwq5u can assume that the speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a parti4ugdb r 8b;cw4 gq2yu7w,9n jqcle (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+xsrda*so6(d needed at the 1.0-km-radius Fermilab synchrotron for 1.0-TeV protons?r osad *dsx(6+ B =    T

  How much energy is release+ r:uj km+zuf;d in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is r q 1bbcfr,9p5dm2 )k6myrnzp8eleased when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produ2fkmedt7;vt d(-5;w 4ygsbp n ce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particlz.1q*bp* u-rtuy: gete were the kaon instead of thprtgy1e t ub*.-:zu*q e pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward eac jwqi5h: axc57h other with equal speeds. What minimum kinetic energy must eachj7:awic5 qh5 x have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must two neutroaya5v8ws40yi o3 ,mst ns each have if they are traveling at the same speed toward each other8tm4i5 y,vyo0wsaas3 , collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range os:+ wg8 f3gjmef the weak force using Eq. 32-3, given the masses of the W and Z particles as about 80 to sg8w:gmfe3+j $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two pt .hsjosonnc. (o6d g *li o, +:7mbdv9bvu)u3hotons produced when a proton and antiproton at rest annihilate? .hgmvocb*3no:d(o u7it.o u svj d9b6,sln+) $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 isola*-xj)lgr7 0f0ofdp n dted electron to radiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram x7*-g fnj0 dr0ofldp)in (Fig. Below)?

  What would be the wavelengths of the two photons produced when am1nd,js k .: qnjfvm-g,gsg13n electron and a positron, each with 420 keV of kin1 .-,,g ndjf:sjnvgqk mg 3sm1etic 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 decaysu,*m qk6un t+c are possible? For those forbidden, explain what laws auut6 , +qkn*mcre 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 decay b6,m 4tdh, gqb); 4x 2dtdenti$\Xi^- \to \Lambda^0 + \pi^-$. 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 electq(f l9crlu-d 3ron 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 estft+ q*g.o: au:qzq mf2imate the energy 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 ofl g2z 0jt,:-*alapfj z the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the zjlplm- ycb+0 z3 n+g:g42 zvx$J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) of 3zs22 zjpj cfj27 *zio
(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 possuk)9i tl 7v/lzible? For those that are forbidden, explain which laws are violated. zuv9 )kllit 7/
(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 (a) a neutron, (b) an antineucffm 6xpwu2 smhjlx0/ 6auws-;7:p1 l md k4r,tron, (c) a :6 wdm0p,kux6 umcjmap;l7 wh4-ssl/ f rxf2 1$\pi^+$, (d) a $K^-$?

What particles do the hdbo -e3ys9;,(n ad xtfollowing 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 to produce a dr l z(llu0,.v$D^+$ 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 qx3 ,a /;7akr5x6na:tn1dkauc) gpy kwuarks (as in Fig. Below) for the reaction t)a/ay:k 6 1x5wnaxr acdk ,npu; g3k7$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the re7vv;f *- ar;oorteo y-action $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? What y4kn4a o -9(wxf,guavv a6k-i is its waveleyfi--xwo4 uk6( av9n,ka v4agngth?
$\approx$    $ \ \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 enesf o,b-y( 7mpzrgy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and approximately how my,p7bfzo-s (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 .1ws8 n6uh bb6vjj8tla positron annihilate each lt6.bbh86j w1svn8 juother? $E_{\text{total}}$=    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 interaction could tyyiqi f*,2.ws hey occur? Fori.q,f yiwy *s2 those forbidden, 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 interah oeljh: 5x0e5z(.waaction could they occur? For those forbidden, explxah(lj0 .za e5 e5wh:oain 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 aq(z73 yc7 bzpap2eq.j $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occursl9e yvvz:5 i0x 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 producing ct7u2t z/yiz e/u(b1k9 5hzv ha pion. z17h2 ctk/yzuv( et5uhi9z/b $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for tho9v jyrx0fu)9 e 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 fermion slr+xfpl ;0zy1-)) dxnz/lnrs are there in a water molecule?    fermions

  A proton and an antiproton annihilate each other axag9lwybc2 - y kbxmx(l9/97 *x rov2pt rest and produce two pions, p-(kmyg 2xaxcx w* llvo /929b9rxy7b$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-calmhb3ijx nbf 4f.qh0tm1m8:)g3 o zc4 jled unification 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 oi fy(vq7 r bi;v6yx,/,- q u8xk4hdlpof proper time, measured in a reference frame where the particle is a;8dyup(lvyi/46ivb 7kx qxoq -f ,h,rt 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 fol bo4oi f 30(z,g yfgaq:a9h /grvg9vk4lowing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model t x av),j9eq.aao describe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of li j8 6jap.mxyg0ght $c$ is the speed of a 7.0-TeV proton?