Give a reaction between two nucleonv ;q7dz vtg8wxa6..sns, similar to Eq. 32-4, that could produce a 6 s..zdg;xv7t wna8q v$\pi^0$.

  If a proton is moving at very high speed, so that7ssh:e n+z hj) its kinetic energy is much greater than its rhjzs)n s:h7 e+est 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 const;. o 6b2 fun6*dnepzhqgp u(k8ituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with our norm6nep oh6n8ufk2bg* q; pz.u(dal world of matter?

What particle in a decay signals the ele6a8ahr7tw7x6j r ;8ntu da u7sctromagnetic interaction?

Does the presence of a neutrino among the decay producj5zm4, j7j7tk b41;i+*ukjb /ud ogpyeum5 j ets of a particle necessarily mean that the decay occurs via the wjjmz4+p7uy4*kmb e be 5o7 uijj, jt/1u;dg 5keak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak intycd a3n4h n,*,c,zqy zeraction even though the neutron and one ofdq*ach,zcnyz y 4,,3 n its decay products (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, grav:u3v; j:rt(zssbm1g q itational) does arz 3: bm s(q1ts;uv:jgn electron take part in? A neutrino? A proton?

Check that charge and baryo+ln+a+3) tg c7m t up* zye;6tvrqwn+mn number are conserved in each of the decays in Table 32-tl6a+7 q3*gnnt +eupvy+czwrmm;+) t 2.

Which of the particle decays in Table 32-2 occur via the electri)2+z rzav -npomagnetic interaction?i- pv+rnza)2z

Which of the particleaecemn8y+k)b) 5a 0cj decays in Table 32-2 occur by the weak interaction?

By what interaction, (wcj :j4 c;ootand why, does $\Sigma^0$ 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 om2/ yk h3tajv(ccur via the electromagnetic interacmkhjayv (23/ttion?

Which of the particle decay-su6(bb4lroeoym z/t*5w t+ bee 77g rs 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" ;aoan;yd8om+xmrav) )w9 g4j that was massless, had no color charge or electrical charge, and did not feel the weak force. Could ;+98vmrj) omd4w ;ognxay aa)you say that this particle even exists?

  Is it possible for a particle tp4z9r oink wx n6;wh5*o 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 chromob )7. edl:eftddynamics, would it be possible to find particles made up of two quarks and no antiquarks?ebe)7d d.ft l: What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not wh2 zx : 3j4a9g;f*:fyxoxplb:kt8tze *vjym v( en they are inside the nucleus?2x 9z :*l:xmaox *vky;p8eb34tyf:(fg tjzv j

  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 6.35hje293 n;jlza- 1ycr h GeV?    GeV

  Calculate the wavelength of 35-GeV t*/xrwc nr7zz+ :ul7cofh.b.electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in whichw7ad- taqh 1c( protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete reve 3rdhtzdf-x3i76.a yolution for a very high-energy proton in the 1.0-km-radius Fermilat . arey73x3fzid6d-hb 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 )6 ;yh )1p9p d)atvl:xwip5aols w t,d32-2 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 nucle1g e l97gtzq*0dn68efy+iqjb us: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nuclezj1qg6+nd7 0i g8 *yqfebl9eton in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees oobm,(zixvd*9z +l )axt v 0j-layhf-4f a cyclotron is 55 kV. How many revolutions do protons make to reach a ki*viyfdaj,- + (zha0-l z9m 4bot)lxx vnetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (m1(w,gih n* aux ;eis,aix/s9$\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m is eoh -is:b-yo8eg;-ttto 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 house the maz. /orhc*bgk /gnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 Te*ohcz.b/k/ grV. What magnetic field will be required? B =    T

  The 1.0-km radius Fex9bd0- 06fkbt mw+hv frmilab Tevatron 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 enertwxf0-6dvk0bh 9bf m+ gy 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 (charge n))dy6fb*n4wgxgy* gu0 ik+/( je h ox$e$) 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 Fermilab synchroof,0;u/e awmbeg wt e(j/rr))tron for 1.0-TeV protorw omreg(e)u /ta)e/ ,bw j0;fns? B =    T

  How much energy is released in the decjjv/sf wm,l ).ay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is releaskel/pz+d4 n d*ed when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to prodqm 7 n6 7gl-yywai jmmi4(pw5(uce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particle werez/d 6kgm/dwa)pupg3 4 the kaon instead of the mpg6agzd) d/p/uw34 kpion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are head93.hkbh mee n0)ues6 gt3zz6eing toward each other with equal speeds. What minimum kinetic energy mustt kh9sm3gnh6 3.bezeeu z0e)6 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 havvu(ch,rau 5tkz)9a 3x :avt wmo7o7.te if they are traveling at the same speed towa773t rz a)vovauk,cu tx.w h5a(mt 9o:rd 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 usixgx;m-ugm/megz )-3 q em 6yghpp:o(;ng Eq. 32-3, given the masses of the W and Z particles as about 80 xeg)x-;g6y :umpe mq /gpmz mh-(o;g3to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced when a proton and antip wpfjjp , d5e(f2u:xpa*pzmt. ;hg, (nroton at rest pjw uj pxd5:ze p(afhm(*2.t,p,;gfnannihilate? $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 isolatedl kabd9)-.pd l21o j hs,7i,9nudusg b electron to radiate only a single photon. (b) With this result in mindl9 d,j9 bpl)ib-,sa7d h2sn oduug. 1k, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produced when an electronrh kv2 n4whr0/ and a positron, each with 420 keV of/rhwkvrh 204n 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 decays are possible? F97k cp- ije1qqor those forbidden, explain wha1e-qkp7j qci 9t 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 enern pb w(o4/z wk+a.e(th d+j/nvgy 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 in zj:8 uul/nzpv/ 0f r0j;wg,vqthe 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 t/q /u45lzz grky5t y1xpxp5:mhe lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width ok.qyh5noy kg/mg 4) we;pc5:pf the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of7:agn6-nhj wh +) toru the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty .,g:vygp8v0q uqm.ts) 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 tfbgvr77ngf r*(3 g,f-a5lp fe8ct bs.hose that are forbidden, explain which laws are violated. b7*srbf-g .3cr fgt58p7nvaf gl(e,f
(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 antinex 8dndtjd r+)*utron, xt) dj+dn*d8r(c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations produce: (a9/wvfbh bryvwd m,.6*) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combhg; k7uh,wf d*d. i/1kya .9/mavbclmination needed to 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) f j:z u7nv,o-to* hpljw5 e6p 8qv54ssaor the reaction :5wa v4 -otpjehs,zo6s* j lqv7npu85$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram m f+ttzbiz )b.ij6v / ,91wkruee9lg+for the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy i lgj5a):pszq0kis w1yv w;i;/u)v 4ois 25 GeV? What is its wavelengt ky)wwiq;4l)sjg50o/1:p;su zii vv a 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 1sr3pf*n5ocr 7.0-km-radius Fermilab Tevatron with an energy 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 *f7sr onpcr5 3for them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released whp (kwm)6*n wlenkclth-q 0 o,/en an electron and a positron annihilate each pwk0 h-/6 m (ckn)lqnet wo,l*other? $E_{\text{total}}$=    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 interarb3r: /rttb xpm8:qmk *xs)m,ction could they occur? For those forbidden, explain why.r x,*xkb/s8 ptr:3qmtrbm)m :
(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 interaction coyy6qhz52q f:tm/k5yy uld they occurm/5y:yy z25yk hqtq6f? 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 a )h1+*q h.uglpl u u cdt:l8v)k$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in tnz ata0rejcb q9*.f94 6ivsu 0he 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, Eqlb n;m7-enx v2d5 yd8n. 32-4, for producing a pion. nyvd2 ne5n;78- dlx bm $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the +gfy w2yk :e8 uhd0(mfreaction $\pi^- + p \to \Lambda^0 + K^0$ 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 th *unn9rx gki-r7m .6deere in a water molecule?    fermions

  A proton and an antiproton annihilate each ofyt *x:3vx xey(-bs)other at rest and produce two pions, :*)tvy(xy e-fxbx3s o$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-calp 8*/qlslqw*rexb /.qled 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 prop4ec ;m77r.ek5:d9 zukvqgpvver 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 measured in the lab, on 45d9c k7 vzev7:pu e. v;krqgmaverage, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the follow71hp-x9sspa ej g; jm;ing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the re u6soxrqz5vdd69r/ o- action $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of ligofu:;0al y osewzg :+2ht $c$ is the speed of a 7.0-TeV proton?