Give a reaction between two nucleons, similar)8zns.c9gymrvfs 7w6u8o .n bwy-(ay to Eq. 32-4, that could produce a yw7s 9o.-y8sg)um8bazn r(cnw6.yv f$\pi^0$.

  If a proton is moving at very high speed, so that its kinet;clhj4f52yb/ z1b u5g eei5sqic energy is much greater than its resthifg5 j5/ l2cz; yqs45u e1ebb 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 constituents of /rc:+nqs)vknym;g (; qzl k iu9if7;nnormal atoms, consist of? Whmk7;zr/(fl9 nqi: )cnygsn+ ;uv i ;kqat might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagne jbmx:ix,4k 85ebkp+8xps ii/mg (t-ctic interaction?

Does the presence of a neutrino among the decay prox0, mt/aqg*1 ek agzt,ducts of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neuam*aq ezgkg ,/,0xt 1ttrino? Explain.

Why is it that a neutron decays via the weak interaction evbvni5 8l ,9zfeen though the neutron and one of its decay products (proton) are strongly interacting? ivzn5b98fe,l

Which of the four interactions (strong 1q2ls;vi.tdxn: du ;h, electromagnetic, weak, gravitational) does an electron take part in? A neutrino? A proton?;;1l:di dh2vqxu t.sn

Check that charge and 7ac5ao -svqty 4s9/rfbaryon number are conserved in each of the decays in Table 32-4q9a-5 t /cfsroyva s72.

Which of the particle depw2bbm,xy+hhxa)+ 3mus5y z 3cays in Table 32-2 occur via the electromagnetic interaction?,a )p+y3h 5whm23xmybuxzb s+

Which of the particle decays in Table 32-2 occur by the m;s-mx2vpm dg.3 ad)y weak interaction?

By what interaction, and whyogae,ykx g6+4hfp22 b, 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 occur via the electrod,y 8a t+o2gmg)x ;8s 5 )fhyjqey.ehpmagnetic interactmd8.he5fqyy8s o2)a;x) e ,ptjyh+ggion?

Which of the particle decays in Tably iza-1fi,20lkedce *i ;n8zde 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 kin4u4g6c 9qwv9x nuasi+d of "neutrinolet" that was massless, had no color charge or electrical charge, and did not feel the q9vac su4wi 4ux+6n9gweak force. Could you say that this particle even exists?

  Is it possible for a particle to be both rv vi qlt)ci;2) *tx3u
(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 cjn-cp1f3 fpy6m7-2vd . kbiz mhromodynamics, would it be possible to find particles made up of v-7pn fdpkym -612z mbj3f. citwo quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when0ovipu 2 wg63: 1soj6yvprl;q they are inside the nucleus:o1glo6vijp rq63yp v0s w2 u;?

  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 )xrcc(:2x xtu whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-rzpye n2*5bhduo ( ./fGeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which przapf:+2. xwqo+ iu)xootons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolutifb,azk/)8d, dloa + ynon for a very high-energy proton in the 1.0-km-radius Fermilab accelerator? To8,dz/akb)+y,a fld n =     $ \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 32-2 abdzflyh* 9 3 d9+,loeaccelerated $\alpha$ 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 nucleus: mcjnj6;:aq t+wxv5f 530-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleqjv5cma 65:;j+ tw nxfon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the d1u uha8; v:1;pet r xphy ixn99(c0kbmees of a cyclotron is 55 kV. How many revolutions do protons make to 9ut;;8 91pyiuhx01(npkx:mrh ve cabreach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengn k4firyfwv92 li ,udq9ln 81(t1m3kdth ($\lambda$, 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 dew /nstv) tle*8uterons ($^2\text{H}$, 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 tm qop;c72q qncctoro6d7.k 2p r: s85bhe magnets for the Large Hadron Collider (LHC) calls for proton beams of7cp kb8q7c;o.: tosndmrocp 62qr5 2 q 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 energige90l zy-sjos2uzw1 +es of the stored protons from 150 GeV to 1.0 TeV. Theg19z0 ssew+zu-yol2j 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 particle (che p,2 ucs/y+mzlcy9u ek* .kq*arge $e$) 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 Fermig:/pr2m,m u9 gwgu-9*cc ydywlab synchrotron for 1.0-TeV protons? B =,:-w m cmgrgp9 /u 2cw*ygyu9d    T

  How much energy is relr*k2azh1 s;hmgog 26b m7d; seqfo. :neased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is xf48hp4e)cfae 1d,l l released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutro oe.n hq5 4d)fc-2 (ocampjf0un pair?    MeV

  Estimate the range of the strong force if the mkdxp .c420idjso0yxq6k v- (. y 3qzryediating particle were the kaon instead of the pionozk.yqivxx026dk d4y 3 py . -r(js0qc. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. What mini9 h.ilj8 h9vhq: i)e-ghm 5shtmum kinetic en9ths jim.):eq hhh -ilh 8g95vergy must each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic ene5/ ikf 6mlwl94qsb 7cergy must two neutrons each have if they are traveling at the same speed toward each othe49i6ebflq/5slc7 wm kr, collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak uqxb o/ep/ 9j-f/ab(m force using Eq. 32-3, given the masses of the W and Z particles as about 80 to/qbmu/9/ejfax-b o p( $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photohyko9 u-ia0q 1uex ;/ans produced when a proton and antiproton at resiq a ;k9yha uu1o0-/xet 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 momentum and energy, that it is impossible for an tt8:f vt1p5vp+ c7sx qisolated electron to radiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. t 71 5pt+qt: scv8fpxvBelow)?

  What would be the wavelength gs t:nbsm;u*+s of the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihils stb mnu+:;g*ate 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 azwc(, 3, yxsm3eyla6,mn . hntnd decays are possible? For those forbidden, explain what lan( 3 6wy3l,h.,scxmynzt,aem ws 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 energ ;q/f dp-hwx6 4 7:b,ijnt:xhsjbf.f ey 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 energy01uksds 91xh/l-ylu,n) tah)qp x es4 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 lifetime of 6u yzci. 8fp5my rx 5k pobv,09 o+amo(t7)ffethe $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width o+ s jj:7 npsq *lnn,ner)60qhrf the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the 2m7)i j(v-jmz3 349hdfucmw, lwfj kh$J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) of *-/fwgqcz c*r4xs xlid+p) d (ah*iw2
(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 forbid(+i,-qv o7 u pybinzt(wwl2i+den, explain which laws are nlb+pw( v i+u7-(zi,yi2to wqviolated.
(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 .30d u x,r3ej ueg(djcrwl0(yform (a) a neutron, (b) an antineutron, (r0edx drel cjw ,jy03g3u(u .(c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations prod5sut) fhjq ( -grvjhb,l5r*3z uce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination n:1xw6l-wqhh 7vat*qjf nm0 1w eeded 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 qz4 nkdi5nasx7 t bn39evynxn29e 2 x(;uarks (as in Fig. Below) for the reaction;5 7yxdis tvne9n4n( xz2xenkn3b2a 9 $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the rea+ a7g 5.8(seaw mv5ciwlm0c iqction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? What i)s0o/iswd)cotld b0 y vl,-)gjq s4p /s its wavelength?sdslbpvd4g0)y )wil-sqctj0 ,oo//)
$\approx$    $ \ \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 energy on .:scn 3t)ehzf 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and approximately how long does it take 3.ec tsz n:n)hfor them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is release rto )o fkf+ 40j1k*tdgnm23sc7lza3bd when an electron and a positron annihilate each other?bjcn kfls z0dg+7 mr231af4*3t o)ot k $E_{\text{total}}$=    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 afz(. ;:oyzu 060q stjdq,agq ore possible, and by what interaction could they occur? Forayz:,6 ( o j t;dqf0qs.oquz0g 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 ar2fue.hssycd1z27+u2bg6mid e possible, and by what interaction could they occur? For those forbidden, explain why. 2y 1uzmh .+uigfs 7bd2es 26cd
(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 xz9gr+-j2 -il2z phl revc *c7$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occohc1 q0cgbyo0-q.a hh16hr.jurs 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 a pion. 3fkp4g s: f0.wq3kkcs(nz9op 933kws cs0kp zq.of4 p kfgn(: $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reactitum:-; to(qbns6p dm/on $\pi^- + p \to \Lambda^0 + K^0$ 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.( ky (tvqt;x:i yo9lb molecule?    fermions

  A proton and an antiprosn9qe4k yc ea 9/1um3jton annihilate each other at rest and produce two pions, cnjay3 ems94uke q/1 9$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-callev6kd nuos*oyuov8exz-*h ix 4skwo (542t+ g9d 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 proper time, measured in xy8w9/ vv v3pqa 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 average, ignoring any copv /3vx 98wvqyllisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the following reactions. ;b fkd vlfk4c3,:5ihb
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to descr5bbof 3)0u az:xirmi- ibe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speedjihy;p kbjz759i7oeogqe - ;0 of light $c$ is the speed of a 7.0-TeV proton?