Give a reaction between twyx .b*7acoa ldp2tt:uz 0 h*1po nucleons, similar to Eq. 32-4, that could produce a ab p1p :.ydxo2**7tc0hzulta$\pi^0$.

  If a proton is moving at ve0 qs3e s ntgc7 dtq-6diqq2v4(ry high speed, so that its kinetic energy is much greater tha7nt( dd2s640qcg-q sq ti3ev qn its rest 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 tymqoafgr aaxrn ,co:hz9382++ty-)ho the constituents of normal atoms, consist of? What might happen if antimatt oa8fynay)+:,c9m3a h2trq-h x+ r gzoer, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signs;y l7 (vwdmt e9)w t1)epwd+zals the electromagnetic interaction?

Does the presence of a neutrino among the decn fknt ,r- g50x(vop6cay products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction 0vo5kgxc ,6(ntf r p-nproduce a neutrino? Explain.

Why is it that a neutron decays via the weak interact4: x1d.h ume/z/6ao- frkdlkd ion even though the neutron and one of its decay k/d ohfdl/zxd4kar m: 6u -1e.products (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, wea2g*d.po 6 etku*c ,m7b-woacej h4a :ss43hmbk, gravitational) does an electron take pak46ote:mbawbah* 47ecmsd2 ocp . u g*sj-3,h rt in? A neutrino? A proton?

Check that charge and baryonyv4f jn.saybp( bi/gg)o0 )-p-8tckw number are conserved in each of the decays in Table 320wc/yivgbk8t a.--(og)b yf)npjs p4-2.

Which of the particle decays in Table 32-2 occur via the electromag(9jh xk4d srz5netic interacr sjh95x4kzd( tion?

Which of the particle decays in Table 32h5nc6qd+3 nr2 vo1aenc a8vc- -2 occur by the weak interaction?

By what interaction, and why, does v nyv0/l)hcs*ba ed-)$\Sigma^0$ 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 occurls dpmvza7 s)wx45 3py5vr-7j via the electromagnetic interactio5 psrl 57dpv43jmw)7sxyaz v- n?

Which of the particle de,rrw,6 +tauuo cays 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 "neutrin5*sm2 9xaagbhiw)kv6e 68iyn olet" that was massless, had no color charge or electrical charge, and dxnhv)6k 69* 5i 2gswaiea8ybmid not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to be both 9e*.d iq.:5 j.xqg1e4tbbp+ze dgrtm
(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 chromodyn(o(ij ay91 f +jgnkv8o4qjlz; amics, would it be possible to find particles made up of two quarks and no antiquarks? What(oyjoj8kz g (94v;nq+ j fa1il about two quarks and two antiquarks?

Why do neutrons decay when they are freekon4)fc8hl1 eq- gqahz:k/j*oeo e( 0 but not when they are inside the nucleus?faooq1ekz h-j8 e :n4o) /*cl(hq0egk

  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 energpy)b e: n arzg*yzvag (,375df y)rlo7y is 6.35 GeV?    GeV

  Calculate the wavelengtlao/h li:daa -20pdr. h of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in whic f ;wf3a2w z4wman)7bkh protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very hidbps p5s n e5pm0z(* pj1rdaa(r 9lp,6gh-energy proton in the 1.0-km-radius Fermiaszpjde6 9 ( *5 0ar1lnp(ppb5mdrsp,lab 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 32-2 acceler,viqg1lt2 i -t 4q+jwvqw*x6yated $\alpha$ 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 pickino .dt 0i;vjb(bg out details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nuct.b(j0v ;o ibdleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kV. How many revolutionsm.wlkb;7qzro , l93cs do protons make to reach a kinetic energy of 25 MeV? s3 bq.rcozk ,l97m; wl$\approx $    $\ \text{revolutions}$

  What is the wavelength aw6 nilalr0 t 8reua xqt8:(00($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius sddpzqzgg2dz4vinb6 38) sk 4k c(,:tof 1.0 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 house the mag 5cw*7b9 sdtzpg)n,/grwbho4y iy:v0 nets for the Large Hadron Colli* n/d49)toz7hs ,bcg0 r wvgb5iy:wyp der (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 enuh l3p3qi jq;,: ph;tnergies of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once per turn. Esti:jp,lh;pn3q u3;q htimate 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 partikx3j*xtfdyrw as/1 y8p+ 1p2nr/n ze54sjq:p cle (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 the 1.0-km-radius Fermilanf:xq1uxito( 9m9czr* f :j7o b synchrotron for 1.0-TeV protons? B ju*z:f xxif qm nc(r7t19o9: o=    T

  How much energy is released wzlnz6mkt d 4(mut* pnn,8s33 in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energ z)ndgjk6s - lkq5:4eby is released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron pa.n5d0 dber3 rl)hlljl(+ n :mxir?    MeV

  Estimate the range of the strjzk*paqk:, u8 ong force if the mediating particle were the kaon instead of the ,q uzj* akpk:8pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. What m-lh4-y2q2ple ,ru 5r rrm7ybyvh0 2me inimum kinetic energy must evhe 2l2y0r u 4rm5,e2 ymr7rbph-y -lqach 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 traveljo,,y , rifq .vp:;qdting at the same speed toward each other, collide, and produc: v to.qr, pfq;i,,jdye 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 mass8s2n jbf d;+4(thfk((rvzblkes of the W and Z particles as a j(zns k82;+bf br 4h(ldt(vkfbout 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths o4.u/2a sfoahn f the two photons produced when a proton and antiproton at restoaaf/u.2h 4n s 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 isol k7:aeceovl;(ated electron to radiate only a single photon. (b) With this result in mind, how can you deolak7v; e :ec(fend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of thxa3o,wj o6u:.z heor62 ned ;d aap)f)e two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihilate head on?32ew;6x rzn)djoho e aua,a: 6. f)odp $\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 deg 7h5t5xcfe;x cays are possible? For those forbidden, explain what laws arx teg;f75hxc5 e 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 producybm2mj( c7sn rpt /wd, +z:uxjf.)2iwts 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 decass0zs 3orbepj x05sg4c418l h y $\mu^- \to e^- + \bar{\nu}_e + \nu_\mu$. [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 th)d -wkl m+p6bwuo9/)dbf q)z.onu; b yen the lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width ofwg28 wl0j6n cx the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the cbc o ba7q8wyayt+47:$J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) . x8* dlvprg0tof
(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 possibr+/gw ,ewuf h+le? For those that are forbidden, explain which laws ae,uw h w+grf/+re 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 neutron, (b) a3( ghcd5 6f8zg+ejrz:xz 0ncbz* rd. in antineutron, (czjdz:+80 (gdz.5 *irb nhccg63ezxfr) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combmoa *r3: n2 +t6wzecslinations 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 produce a (/oqg ka4c:9nz 2zmoja-c j/f $D^+$ 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 usixp15ndyi 1fn *5u6j9tic ( zlbng quarks (as in Fig. Below) for the reaction d5n t(1ux fjpb9*i5cly16n iz$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the rea4cyvqb3/ j*l yction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kind249ql lmag dln4l4x1etic energy is 25 GeV? What is its wavelength? 4ddl1 4qgxml2 n4ll9a
$\approx$    $ \ \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 m+* ut*g fjskp3ow x70wo8 +ljthe 1.0-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 approximatefx3+pjmog+7ljwk o w8* * t0suly how long does it take for them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is releasehxd 4fbbp1, *fo58gd0u)vt rhd when an electron and a positron annihilate each otherrb1bd uptv)0* gh x54f,f8doh? $E_{\text{total}}$=    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 interacty to4o zq,-jh9ion could they occur? For those 49zy q,hjo- toforbidden, 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 ar(9t71qzxlv bcodb*f.- g zm(r e possible, and by what interaction could they ofborqv7(t xb1 l m9- g*z.zd(cccur? 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 x-+pmz1 ef q6 clm0a5p$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in t. uffv*5ny a4tl o+h*ghe 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 p (t koy.y 0mst9e5kx,zt6 3+ldzl3o ksion. (03x,t6o95. 3y ldetkyzk s zslmo+ kt $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-valu/oo vjxwr:62a (8enyce for the 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 therey;urj hcs2*l( in a water molecule?    fermions

  A proton and an antiproton annihilate each other a;cc sq5*u 8,79tdughnwsmxv 6t rest and produce two pions, th s;v dq uc87wnumcg6s*x,59 $\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distang r9bie d2mc(a6:l- sgce 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 ud 7,49qkhku i,v-lohin Table 32-2 are in terms of proper time, measured in a reference frame where the particle is at rest. If a tau lepton is cqh,v7ukdh oi 94l ,ku-reated 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 in8za yi(( d)wr2gtqfx4 the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to desct7i47g6-f xucbj(ci p ribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the sp06i e*hsd6aew/ a:ysceed of light $c$ is the speed of a 7.0-TeV proton?