Give a reaction between two nucleons, similar toskgo0;j1 vh*0tvrix48ac g q3a zj+*b Eq. 32-4, that could produce a ;aa1 s8 tirq4 v0xo k0zv*j *ggjbh3c+$\pi^0$.

  If a proton is moving at zvclh3loz1.0tjya3c8d :;b fvery high speed, so that its kinetic energy is much greater than its rest energy1 cza c8j lv.ftdb3:0oy3hl; z ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticles to the constw nn33tqsh mig(7 nw: ;buka:/ituents of normal atoms, consist of? Whnth37n(q: ; abgw/km :s3iunwat might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electrom batf87 7dgco9agnetic interaction?

Does the presence of a neutrino among the decay productg zga )avi*)nzo2y-n.s of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? yo-a.gz gzi2 n)nav *)Explain.

Why is it that a neutron decays via the weak interaction even though the neccul,b .p)ma6m0(, tppq cwj*utron and(pmccp )ctm qu6,bw 0.ajl*p , one of its decay products (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, gravizola//q5-h ls/:xktbtational) does an electron take part b oh:qx kz5las/-t// lin? A neutrino? A proton?

Check that charge and baryon number are conserved in each of the(sc97(uux mnp 6x,pnd decays in Table 32-2m97n6p(( dp usux cnx,.

Which of the particle decay;-jpj 9tvnndob 0hhmkj0 g9 08s in Table 32-2 occur via the electromagnetic interactiokhpj9d0v nb 8 gjhnj-t0; 9m0on?

Which of the particle decays in Table 32-2 ocze5)d. nejj)m cur by the weak interaction?

By what interaction, and why, eb7 e9uo4o/;q xm,w (dn,vsf hdoes $\Sigma^0$ 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 electr3az1d.u0 l4xu*kzxf5v b fz-comagnetic interaction?u5xza 3 ufbfc zkd-*v4z0l x1.

Which of the particle decays in Table 32-4 :+* ws mqj5zdkoccur 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 massl2-fg-r zgesa. o0 p6j7aksl5o ess, had no color charge or electrical charge, and did not feel the weak force. Could you sayf az0o6-2op.l sar75g - jkges that this particle even exists?

  Is it possible for a particle to beny- 4g34sj9,kppyrm9;)6dp wn 7qehnj3bzq a 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 ) ,a:szusbjhk , ;0aoxit be possible to find particles ma,0kjbsshx z :u,a) ;aode up of two quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay nk.45xba vfo81/ shd uwhen they are free but not when they are inside the nucleus1d4a58uv .f/ko hsn bx?

  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? .,iffnwsi1 9yr,3 ib v   GeV

  Calculate the wavelen6/ 0c nyukonq;.h3acygth of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protons +x-+(gcy 8zq owt4nkomake $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very high-energy protb.4o dgyqehtkc8 3ys (+9qk3 jon in the 1.0-kok(9ytsq k3jgh4b+8dy3c.e qm-radius 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 Example 32-29c5mxe hunlfr5;ah:kq 80)y7fj ei 7x 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 nz8y ,r2k* xg44 a svv 2mfx)4jjl:orivucleus: 30-MeV alpha particles or 30-MeV protons? Comparevszgvv2i m4, 4ayo*j42l x)8 :jrrxk f 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 m+t mk2 hs)vo;rany revolutions do protons make to reach a kinetic eo 2k );+vrmtshnergy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengtu(y6xjg 0uuj/ ivr0(ih ($\lambda$, 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 deub 7q 1q/jmk twf:3vpm:terons ($^2\text{H}$, 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 lrx e c 9frx-wj (q/d;;q /z8audzal+ ek5ah1/used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic fij/r(ah l d5/akqe crx1qaz-u;;/eld +wx f9z8eld will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds to bring the energ9ja m3vdpk 1d.ies of the stored prodd9vkm a1pj .3tons 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 is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a partica8 ckkcbf ap0)2)3elsle (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 inten r+rikxwc2/d6sity is needed at the 1.0-km-radius Fermilab synchrotror2 /rc+6ix wdkn for 1.0-TeV protons? B =    T

  How much energy is released in j5aa1.3m cocjzr0z j 68 *ecnzthe decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released when 1sfvp*h b g+o:a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutran7w+idr6 v ji3t-yd* dp)2 cscyp)v7on pair?    MeV

  Estimate the range of the strong force if the mediating parrmg33xdc4k9c ticle were the kaon instx3 gcrd3m4ck 9ead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward eaww w-r)ic*h9q- wagl /ch other with equal speeds. What minimum kinetic enrail 9*/ qg-wwwwc-h)ergy must each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energexkgz8j 9 )e ,47(vj otkmlha8y must two neutrons each have if they are traveling at the same speed toward each other, colmljzk vgx4a t9(h8jk7e ,o )8elide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using Eq. 32-36 tilbh i817 sx3,,bf eh+inqrna92gd , given the masses of the W and Z particles as about 80 ti geix, n +a7r9h , 3hq8lnbbdisf162to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photonz5s dbmh kga4 zx3q h0irpe:am(8)*n)s produced when a proton and antiproton at rest annihilate? aeaiz 4) b* 5q g: h)zr8xmpnm3khs0(d $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 9rk2q xojv r36for an isolated electron to radiate only a s v kro3692rxjqingle photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produced wjp 0 f:twh4wr4hen an electron and a positron, each with 420 keV of kinetic w0rw p:ft jh44energy, 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 reactbhu:dt+ j)8v2ujo, c gq au4a;ions and decays are possible? For those forbidden, explain what lawdu :uo a;2tu 8jb+ch 4ga,)vjqs 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 decay*(g go dil(uftfzi8 b :8j2lhx4c8xr -0j(uek $\Xi^- \to \Lambda^0 + \pi^-$. 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 ei d(r15av-s9gdyr k5 gnergy 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 and then the lifetimebnd rus9v)8;j of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of the) eq , y6mom7y)lipqdc.5(c:1kezv;df 9tqug $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width o3;6vywuz fmsm7h bv. .f the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncerty8hd r q,8m8b8zhlb 2painty) 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 dec1(fcolclqw;xw8. c9 otg//tx2 cly1j ays are possible? For those that are forbidden, explain o.jt ccg1 8fclty ;2x(19/o clqw/ wxlwhich 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 combinations that can form (a) a neut a6rna64g*qqxh6;lv23uj g g bron, (b) an antineutron, (c) aub2 grq l*;xg6q h64a va63gjn $\pi^+$, (d) a $K^-$?

What particles do the following qd/dur0l ;x4fsj l9pf 0uark 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 tx vv 7kp-3qm5qmz3 7tlw5g mw4o 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 Fja(dp)w ud7, z 1c y9gvs8q*ekig. Below) for the reaction w z,dgy(akuve9j81q )7 *p dcs$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the reactiogw 4w9bj/m ,iwfzqn29n $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is bkf- fg,gf,n5 n:e+ cy25 GeV? What is its wavelen+eg ,:-fyf cg,k5n bnfgth?
$\approx$    $ \ \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 Tevatronk o8e0s1s/psh with an energy of 150 GeV. /s1h ekps0 8osIf 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 releaj/ sw.p nbkbsbhdlh:b,7+ ftyz ,fw) )0+x.npsed when an electron and a positron annihilate each other?h0wk 7s d) p,xfnt+,lb:fbb+)psy.b/h n j wz. $E_{\text{total}}$=    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 rearhv/3 ie:eegc,))c q +hwvc0bctions are possible, and by what interaction could they occur? Fo0e+ce:c 3/bv)wgr,eqh i )hvcr 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 iuax+*o5ic )m(x4 fyqwnteraction could they occur? For those forbidden, explain why. x+m *ifay4o(wux) c5 q
(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 b 7+ck 55tv nvdvm)n,+dl83ds1 swl tf$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurcblk43gki ot/ u, 12dlqw1d t6s 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, forjf0i8i1mr (fas9 o,j o(z mmxg)7/ecb producing a pion. ofexig c, o0z1f rma7j9m(b/j(8im) s $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the rp:-yq- uwjs e)eaction $\pi^- + p \to \Lambda^0 + K^0$ 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 water mol ,-wi hqskc75fjc:x0l ecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two pions, tg)jy d+8x q-v tqv8dx+jy-g )$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-calof(l:tr nmry3q;epju. ;wf:( /szw- kled 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 of propersf4vpze09u 9 jw:huc o2 ss:l; time, measured in a reference frame 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 meh9fls :4 zs;we pu2u9ovc js0:asured in the lab, on average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particfyay/r74aipl k6. ko +le in the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to ugyh qyz9z850l ;k pfpl+n; nk8 1k-kqdescribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of light 3 mkl /baobpq *tzs(;5$c$ is the speed of a 7.0-TeV proton?