Give a reaction between two nucleons, similar to Eq. 32-4, that could produce 1ls5 q 80cx/w;zwxaxf- sw(k q 0)hukza kckq50/w( )8uw wxxsx sh;z -za1qf 0l$\pi^0$.

  If a proton is moving at vee4 q0inkb 47b8c/ lf)9j2njxixsn1tfry high speed, so that its kinetic energy is much grea c9fqx/n nsitx)in44j1kl8 be7j 0b2 fter than its rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiap 9w .eu6wrc3yjn+s64k y n5ndtom," made up of the antiparticles to the constituents of normal atoms, consist of? Wh9ce64ny+.jnyr6ud wn pw3ks5 at might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnc3- blc vv(4wketic interaction?

Does the presence of a neutrino among the decay products of a particle necessarr(kaj tm3x 6/s(tzg :x2ksd )oily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Exp)a:j2d3/gkk (x(tox rsm zt6s lain.

Why is it that a neutron deoy *rm*w4z foh)8sp;kcays via the weak interaction even though the neutron and one of its decay products (proton) are strongly interact;p 8os* k4o *mw)yhzrfing?

Which of the four interactions (strong, electromagnetic, weayy an8mu5uk:1k, gravitational) does an electron take part in? 5y n1umau:ky8 A neutrino? A proton?

Check that charge and baryon number are conserved in eac4 afkfk,9zzn.+qg n0uh of the decays in Table 3f4nuq9ka,0 zf.gk zn +2-2.

Which of the particle decays in Table 32-2 occur via the electromagnetic)z,xpgmkl xg/ 2ar*anyt d, 0* interact l) *tg,andkx2ym/a*0p, z rgxion?

Which of the particle decays in Table 32-2 occur by the weak interacti nk ,nqs*x +e0gvy9y)ion?

By what interaction, and why,dkkp r /yxoat*ef v;wiz2w/8q7- mj*3 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 electromtbus 5xljq96 .z jr()mmm tp,;agnetic interactmtxs).(, u9p5 qbm6 zlj tjmr;ion?

Which of the particle decays in Table 32-4 occur by :7ym1t(:dvcew(kr d gthe 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 massless, had no cyp/).lh/v-s7jl;ykke (ovbn d ;u )twolor charge or electrical charge, u)y/hv;) .wll/j( y7bp t;koveskn-dand did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to rzkjsp 5r1vqd/)d 6r;5yup8tbe 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 chromodynamicw8hh/ 7o jea6b)n* necs, would it be possible to find particles made up of two quarks and no a ochw/hn6 ebaj87 )e*nntiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when b 1iohk+g9(:ncpi3o0 wusza9they are free but not when they are inside the nucleusw nhk+zsaub9(1c: g3oop 90ii?

  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 : nxdi,ees*8vkinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 3n tedz:e6, 5rm5-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is umz57o1czu vpmn* 0j/qsed in 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-energy pro:yp adu ah a 0qkbyf.5/bg5sxox*n25d;gg 7.n ton in the 1.0-km-radius Ferpb.a qnskghy57 n*;5:ddfgax . 25ug/0xo byamilab 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 tacss / sk2+-xmh 8,oiExample 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 details of the nucleus: 30-MeV alpha partic71)o0hcg( 4rqjyq dn-bjjrl)les or 30-MeV protons?bj7 r 14dj -)r0qhyc g(q)ljon Compare each of their wavelengths with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the deo1u-/dyn 6rmcyisl1) es of a cyclotron is 55 kV. How many revolutions do protons make to reach a kinetic 1mrso d1n luc/6i-y)yenergy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (j;b x.- 3cj3csy2dzgt$\lambda$, 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 deutero5g/f s;f-wsdnns ($^2\text{H}$, 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 th9dtw4 vt g9te7)hr8kne magnets for the Large Hadron Collider (LHC) calls for proton beams of enertv 7wht9)gn dte894krgy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds to bring snsn -k94xqyo c;.s)ha6f+m qthe energies of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once per turn. Estimate the energy given to theqnfqaxy; s-o4 +9ss)6h n.km c 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 (chaabw z;o0y l*)h, bqnc8rge $e$) 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 synchrosn*jc,k3/ ov4r iot/n tron foc ,4 o so/v/irn3kj*tnr 1.0-TeV protons? B =    T

  How much energy is released in theal 3gvna9k8n 4 decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released when27wz:sdc jwmo0u:de1 g tre*nj 7*. je a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron pair? bu, zk ;fqkw9q5qu8(n    MeV

  Estimate the range of the strong force if the mediating particle were the qm np0:6has18/v oiv:s0xqp dk/f)mqkaon instead of/oxq18p nv h/ )q60aq ki: mmv0psfs:d the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. What mt dl7u kh2)kiuc2g ql+ ,xho.5inimum kinetic energy must each hi7 k t)l xclk5q,uuhd2g+.2 ohave 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 ha81 .d xeoatvxy/1td;mve if they are traveling at the same /mo vde81 ;d1. xxtyatspeed toward 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. 32-3, given the masses of*dw(vhl799d0 m1ckpr0,vs eiwlp j-o the W and Z particles as about 80 to-clk w1v,i0lo dwh jpmd r99pes0 7(v* $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced when a proton myo c*txz r96gt)w,+uand antiproton atz mxtoc+r g*w9t, )yu6 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 momentum and energy, thakt1-co:28aog c h3 ewgt it is impossible for an isolated electron to radiate only a single photon. (b) With this result in mind, how cangw 2c3kt:ocg-8hae 1 o you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavwee c 38ktx86:e egjpv) *tof0elengths of the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihilate he) :w 8et v8fetg0oeexc jk6p*3ad 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 areb hb 3 w3uyet83-8di- l b-jjdrc,ae/t possible? For those forbidden, expl b,tde-l/ jbi8u 33t-yrbjdc3ea-wh8 ain what 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 energy of each of the two products-oxzahpwn+t, 3bn .cq08 pd9p 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 the decay 7id wuy,sy*k ,$\mu^- \to e^- + \bar{\nu}_e + \nu_\mu$. [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 ener 6n/j* louow;kgy 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 of thetrsm-:c q.r k+ $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of thep 5pi7 g9ah /;ur9fq,gd9 nwoy $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertgvyss33 bi983 sjgmm,ainty) 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 forbidden, exp hx.aqx wsas/27nc))k lain which laws are vx/kaw7 ).sqcna2) sxhiolated.
(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 antineutr :mw)g6,bh f2x( f g.f5yimi)w(txj zmon, (t.(6hx5m,mf jg): iw b2wg xffmy (iz)c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinatikoo ph(7pir430p wgcgg;u)*c ons 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 profv5;aidh1 yjixs0;a+ duce 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 Feynma4 h khxzt3m5j/n diagram using quarks (as in Fig. Below) for the reactionh4h3jtmk5 /zx $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram fo 1+i xaz 1u+qa9rdrdw+r the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of( c2qfuv0bj0 f a proton whose kinetic energy is 25 GeV? What is its wavef0cq2u0(vbj flength?
$\approx$    $ \ \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 withj 89c gzbwf86(azygk , an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, , 86k89cg jbz(a fzwyghow 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 released when an electron and a positron )-urg+zdq *fd c3j (nyz+7cpfannihilate each ot+-yf+n rjzzqd)g3 u7f*pd( cc her? $E_{\text{total}}$=    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 interactiojhmt ekj7 z4e;e vq3+/(v7)m vfacq(cn could they occur? For those(q+amq347 ;ech) ekvm cjz(fe7jt/ vv 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 interaction co 7a7;g1t*unbwou 1 ;a *vdzbxeuld they occuro;1 *g1bzbwv;7anuax ue7* td ? 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 anvea 85relwwctu6;6m5mxo6.e5 60oh k2dcaq $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak t-x d)umtli45 u his3+mheory 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 produc0 gdx5vp- m(dw fvp-i:ing a pion.g0(-m5viw f-dx:pvdp $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reacta4 )2e 0u:x0nbmzaere +/dj tqya9 pw,6a,hobion $\pi^- + p \to \Lambda^0 + K^0$ 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 wateufm+3 2vy a /md)fi;tt,;jrd kr molecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two pio:tfvf-l *hvl ,ns, ,tf fl*v:hl v-$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unificaf1 i), julgl eaoq65c*tion 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 1 v8m/hnk *:xgfksi4v4 k, tqra 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 4 xrtkk8g:q v*hvf/kn, si4m1as measured in the lab, on average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the followingg:uyw m) 57i-ex tgfi5 reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to descr/)u i.q sf vc9a izqxb8:jt74qibe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of lig-gpq*t0 nj0xyn iul59ht $c$ is the speed of a 7.0-TeV proton?