Give a reaction between two nucleons, similar to Eq. 32-4, that couldb,7)wtdkci 4 koa i:i5 produce a kitk:wc 7o54 aidib), $\pi^0$.

  If a proton is moving at very high speed, so fu 2p y,yqeq*7 ys;vx(2munn;that its kinetic energy is much greater than its rest e2 qu sy;eyn x,p*(n;vu2y 7mqfnergy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticlgd5 bxfl,f , 9u7jjbt5es to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in conbdjb5 gf tfu5 ,j,79lxtact with our normal world of matter?

What particle in a decay signals the electromagnetic interacno uh7+bhw8aoy3 mvu(-e xhvux5u-+ 1tion?

Does the presence of a neutrino among the decay products ofm7gw,j lq. k*-w0e y3supawb 9gpp, o5 a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak intera7w,yg 9g.owppsm0j,-uw* lp kbaq5e 3ction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction even though thn qdn4 qj *0im+b-pbx7,iri3ie neutron and one of its m pri+qi7n ,n 3*iijbxqbd0-4decay products (proton) are strongly interacting?

Which of the four interactions (strong, electromag25-s7k5fsaj ;dq pm penetic, weak, gravitational) does an electron take part in? A neus j7kde52msf5qp-; p atrino? A proton?

Check that charge and baryon number are conh: 7os wx 2b(yjqki4:eserved in each of the decays in Table 32-2.:( 2bs :7iqkj4 xyweoh

Which of the particle decays in Table 32-2 occur via the electromagneti)0ogts ,oxt9 kc interactisxog9o, 0tk)t on?

Which of the particle decays in Table 32-2 occur by the we5jwbv 5- sd cvi9b(7;fr:iku lak interaction?

By what interaction, and why, d.* +c2lxe.q ymiu 9zb 70wlp).mobqueoes $\Sigma^0$ 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 interfcoaug 20c5eh; 9q3n0* a4fgoy1nn itaction?1g;eo 32chfng qt any n*4ai9o0uc0 5f

Which of the particle 3inw,/vn;lr ,tm) 5zpo 0lzwsdecays 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 7 nb1 bu.htb4ra69srcv6/axp kind of "neutrinolet" that was massless, had no color charge or electrical charge, and did not feel thevh/xp4 sb69a 6 .rb7ubar1ntc weak force. Could you say that this particle even exists?

  Is it possible for abr3d;yn z-t c1wr4 vw+ particle 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 chromodynam rf:g2tqz*jr aw f0-3qsw3qagf9*iu2ics, would it be possible to find particles made up of two quarks and no antiquarks? What about two quarks and two fwz2q90wqfjuq*2tisa3* g a f:-3g rrantiquarks?

Why do neutrons decay when they are free but not when t4kzue 1(9 98pah*jddaw u* hujhey are inside the nucleus?a*u8j pwh*(41 e9uzhjkudd 9a

  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.giiiyxzfgdlttt ) 44 2.h9k07(6v zt c35 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons. Ef5 x/vn+c1+z jg4q1rs*elhz4a oj3zw =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used 4 x,av;c )xhl: ic1odvabgd/ 6in 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 high-ens,b(47 eynfem*s ha44+qdzbahkm/4 e ergy proton in the 1.0-km-radius Fermhq4sam/f44,*eeb ey4kahmz d 7 sb( +nilab 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 o pz/yotg :tv 87c;x19esjm pa+f 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 det j nl59 au:0- *g0vtoilhj3lryails of the nucleus: 30-MeV alpha particles ohl y5 :lu*ljj9tg irn0 v0-oa3r 30-MeV protons? Compare each of their wavelengths with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across twg 80-hqdr q-zckl +t8he dees of a cyclotron is 55 kV. How many revolutions do protons make to reach a kinetic energy of z+k88 0rwldt-g -qhqc25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengthq blg/ 5h3;swhqdro:b98prmm+qz k0/ ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1awz* - r)dsh:t4kl h0y.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 tunnel that will be used to housm9k5 g-bk4uome the magnets for the Large Hadron C9o-mm kbg u4k5ollider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds to bring the ene5k9wpi4 k4w :x3cdcwargies 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 o5cw9k p4wa3cwd 4i x:kn 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 * ;7zsnldnbii8c+ exk oi //n: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 thbwc8:3ir ho2ce 1.0-km-radius Fermilab synchrotron for i3cr8bc h2 ow:1.0-TeV protons? B =    T

  How much energy is released in thwnq*( 06ckm4 iucks 2be decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is rere:f5 wt+d /ez55- dfxn8c wtrleased when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required toimyy 5 8(fhocyeq4)c/ produce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if 6waxu9+ ega1 lrdr+, ejgn)r9the mediating particle were the kaon insn1agxr )ud+w 9ejrr9+ 6l, aegtead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward eov)04uj0sattzg ,p wvc8o.i ;ach other with equal speeds. What minimum kinetic energy mjs.a; 0 wvt4z0o vcuotg8pi,)ust each 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 vdh6 p,zpl nx)fvr087 traveling at the same speed tow),nhxvp f 8 7dp6rzv0lard 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. 3o7p iild0e06 +on:( otw,+hzd6ovgt: pi ,ybe2-3, given the masses of the W and Z particles as about 80wit i+0:hzpei7 p ,t,vly0e( 6go6ddb+n:o oo to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced whenqoez)hv s,0 i8 a proton and antiprotoo)sh8vie0q ,zn 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 momentu f3kvu0enf7(f w.3r wxm and energy, that it is impossible for an isolated electron to radiate only a single photon. (b) With this result in min330v7(eurwx f fkw.f nd, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the twnzcy.zt kq.3.o photons produced when an electron and a positron, each with 420 keV of kinetic energy, annih. .nqt kzyzc3.ilate 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 rex:ku(1+7(wd wj 6w4: xe2lzpmzrt jbdactions and decays are possible? For those forbidden, explain what laws arelxdp6:7b 2 z1 w((tmx kejwj4 u+w:zrd 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 72zvk+c,uk zq energy of each 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 i8:dc6af9.w az b6u0ur.j/q rx zg 1cain 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 energhsuu ;qwj .p -3oim;8py 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 ok)wt tpr9kta7o*;fupegni y: 7 6(/ibf the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of z c720r jie1ydn)svn; the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertaindgzirn t jf.n1-x2+t/8;ogbkty) 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 forbiddviv lpo ;)b nuu+7p9tj ej3*9xen, explain which laws are violated7;+ ) v9ile9u pnjb3 vxtopuj*.
(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 thc3kt e s0:yn8fat can form (a) a neutron, (b) an antineutron,sek 3fc8t :0yn (c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combsj6klf5w0:g y)a;v-f zv/hh uinations 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 t57qzl 7hthg 9xv9apayt d/3 5so 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 ic*p)dp wi.tb+ b b,pns7g 8+zthe reaction* dng 7b )p+ wipc8ts.ib,+pzb $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the6jkmg3m4xy-t reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy a*xlt7cx:9wvb.cg 9a is 25 GeV? What is its wavelengtb a97 x9v*ctxw.gc:al h?
$\approx$    $ \ \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 +3gd bb,ejuux-bnl2.xe: k aabq :e):an energy of 150 GeV. If they are:j:-bn buelqa ,b 3ge2u.) k+xb:eda x 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 is9ysms7: x u5mhgf5tr9 released when an electron and a positron annihilate each o5 y9tfmrsm7u9:sg 5x hther? $E_{\text{total}}$=    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 ev 9 0db:1b lpsxdcll3f: qc),could they occur?: peclsl l31:c0,9xbddqf b)v For 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 wha 4k8qj c:qb/-ei x)rwut interaction could they occur? For those eib:x rcuk4 /qqwj8)-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 auy kq3+m :en )n9jr+jo $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak theo n,alg*w*mob -v kcdz3t9oz891qm sp6ry 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 thegi sf9s szh1o; k4da7/ reactions, Eq. 32-4, for producing a pion. sk7zsad/1 s49h; iofg $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the 7d q0:fp(r ts7r4tmld 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 therelh0:blec: 7 ba in a water molecule?    fermions

  A proton and an antiproton annihilate pmtwl7 9;jmd :each other at rest and produce two pions, wmt;7j d:9plm$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distance kib6 pnsd.q 85of $10^{-31}\ \text{m}$ 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 prepa7 1*ao8u gs68q rszoper time, measured in a reference frame where the particl6*aa1 gsq8o8s peu7rze 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 fwmt8b4, z mb4lollowing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to descri8vhnpd 6 7.i+ ms2)vnbsxi5 krbe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of thep t1 eivy,5pe/josre.(+kc 5d speed of light $c$ is the speed of a 7.0-TeV proton?