Give a reaction between two nucleons, sijltl(z 2 1l*ibmilar to Eq. 32-4, that could produce a jil(1l 2t*lb z$\pi^0$.

  If a proton is moving at very high speed, so that its kico +ky3i -bbdw+lo;i8zedx0mj 4k n60 netic energy is much greatci0dz48-lko306jd oim+y ;w+ bk bnx eer than 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 to the constituents of ad u/x*hy.s6 tnormal atoms, consist of? What might happen if antimatter, mast *u.hx/y6a dde of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic interaction?- y40(ezragb0 ll7b hl

Does the presence of a neutrino among the decay products of a particle necess lyqwg(/.pib7 arily mean that the decay occurs via the weak iny bw /7.(ilpqgteraction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction eveoodum3: qfq6i 9e1b 05bfnbk; n though the neutron and one of its decay productsun9o1i;bd5o ek6 fm0bq3 q:bf (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, g 8 pet uc*qrxag*5s-v8l yd22bravitational) does an electron take part in? A neutrino? A r pe52qt*y* lbcg -adu2s88xvproton?

Check that charge and baryon number are conserved in each of the decaymdu1g q -qq42m 87xrvhs in Table 3mqm42q qvr1dx 87ugh- 2-2.

Which of the particle decays in Tc e 7h x)a*w juytsxt-9a4t95uable 32-2 occur via the electromagnetic interaction?* taw-u7x)95yxhue cjt4 9sat

Which of the particle decays in Table 32-2 occur by the weak interaction?8uafa0iq;f f8 g-5; hik 0fuar

By what interaction, and why, does9xun3.wgd7 vgd)m a 2v $\Sigma^0$ 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 elec,uxaenz*gk. 6: 1c(qn(uxcqi tromagnetic interactionnangqei x(qz( u1*6.:kcx,cu ?

Which of the particle decays in Table 32-4 ;zokbl44w zx2g:zitt1j*i,f zt ww0, 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" that was massless, had no color chaf )ic9a;-pz-6:wl riq8gab vorge or electrical charge, apb- rfwloi a 6a8g9iq:);zv-c nd did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a par9vw5)jiqr: 6 cmao,wf xx8rj. ticle 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 chromodynamics, would it be possible to find particl -,1sji.w ff:dr.oohhes made up of two quarks and no antiquarfsfdw1h .j-,: .orihoks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when they are inside the by+j.im 54: ra+omm3a01mecin h-fhfnucleun0ho. a 3 fmi+fmr-+:ayhbc jm1emi54s?

  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 6.3eqci4 ) srd:qt htnzhy1.m a567se(n,5 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons. .27 fpy(opmfg *bbw5j E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic fielphc7d8lomt3 2mw.;,mc:,hrqn s x w m.d is used 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 hisi0 s cir8r37dbl4381yk: vbftf vbk8gh-energy proton in the 1.0-km-radius Fermilab acceleratosf83 k t0libyb r d:sc3bk4vr8f81i7v r? 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 accelerated:* c8csuq dil2 $\alpha$ 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 ofl.p:-h )jluoo1tad g.d630(9mqnzpw)x myqx the nucleus: 30-MeV alpha particles orz.m.lx0ahm)oglp)d xq:(3 qu-oj9 dypt 6wn1 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 the dee+s,rjn1 tx 9/e8eb/nv bocdt 2s of a cyclotron is 55 kV. How many revolutions do protons make to reach a kinetic end/rv82 e9x jotbn/s, +etnc1 bergy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength 0n ,juv8mwip3($\lambda$, 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 deuterons t oso;i :m:io/($^2\text{H}$, 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 magnets for the Larx ;z;t:o uofranb).i-.ske n57k5eesge Hadron Collider (LHC) calls:at 7inek;k5se -b;u5)sfe .o on.r xz 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 secondsywk+p dm 0 *s y(,5 d1iob94:rsouqb n8f(kyrg to bring the energies of the stored protons from 150 GeV to 1.0 TeV. The acce 1m,yr4ik (9yokd(: 5s n g8qbdrwu obsf0*y+pleration 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 (charge7 x+ 3rsts*kpv $e$) 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-rad9ks+d : ugxrx;ius Fermilab synchrotron for 1.0-TeV prsdkx9 ; gu:r+xotons? B =    T

  How much energy is releasee jn*+cj(x06 q ul-a:ivkgx. bd in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energ xjc 1.4xmua :cm/(ruiy is released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron pair? m/.piedt: g2:dhg3o4tlo4,ww2 xs f q   MeV

  Estimate the range of the strong force if the mediating particl/0 m3o9b re.g4r1nj7 0iryqxb weywl, e were the kaon instead gl9b7/rnqxey w y ,4j031ei.rbor m0 wof the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading tf .: +dxjm5h)s4z m)jszj )qv9mktq2soward each other with equal speeds. What minimum kinetic enerds.x 2m tjqzjvhs 5m9)+)s fk:z)jm4qgy must 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: * aqq4x.0czc6fj 33gsstrsx have if they are traveling at the same speed toward each other,.4 qf qj6c0g tsx:3sr* zc3sxa collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak forcer7+lsc6u;mwuo(t-afrv 8 rs:6:maew using Eq. 32-3, given the masses of the W and Z particles as about 80 to vcr6oemau:w ulrf7( r68s w -s:tma;+$90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two 1uzu o.jkf-wc )d (k qm00kd:fphotons produced when a proton and antiproton at rest annikd( -:q u0)1z ouwdjkm.fcfk0hilate? $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, 3o(0j 7)dddqzu*qx 5 o+ owdgvthat it is impossible for an isolated electron to radiate only a single photon. (b) With this result in mind, how can you defvqdd5j)0(+7dwo oq3d uxog*zend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two 4di dfzfz /8(j;(vxcmphotons produced when an electron and a positron, each with 420 keV of kinetic energy, annixzz ((/48vd;cdif fjmhilate 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? For thosw6m6s,ucm.t r e forbidden, exp urmmst., cw66lain 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 ofhgc l,b4i vce:xgjja9f*, 6m, 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 ener/et67cyx-1zdqox:yy dlvc e /ks;. -ugy 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 thetv2-, m dejz8a energy 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 the0lz 0z /dj6lwc5pstu8 $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of v 51ujyxaoj493ikko, the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uni6i j 8kfzf(a;1 .mlcrvf0 w2acertainty) 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 followinv od; dvi32 wdxi1z*9ig decays are possible? For those that are forbidden, explain which laws are violated. i3i*izdd wdvv;1x9o 2
(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 fn v-y2(uf/uidorm (a) a neutron, (b) an antineutron, (u2(n- dy/vfuic) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations produce: (atc+d4mbo zm8fxcq 4/b z)85dr) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination needed to produce cjx4hu 1 mf7kz rfl02,qoexd92, 0gb .eok7gpa $D^+$ 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 the re*zg u ym*rdkj00 ioh30 1y)gjjaction *jgmo0z3 rj* 1yj ighkd0)uy0$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram fnxjhb1-z1v1b/u*eru no a/l5 or the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is)7 9lqyi6cynxl+zm ,i 25 GeV? What is its wavelengt7yql 9lminyx +)i6,czh?
$\approx$    $ \ \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 energt3pudr*ew.v7u(w6 yjy of 150 GeV. w *6d.uvrej(pyw7u3tIf they are 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 is released when an elmf c iv0q.xmipo (fu..ey. ;7aectron and a positron annihilate each other? of.. qu7yp x.. immevi 0fca;($E_{\text{total}}$=    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 bh(qjhs*5n i9bbourh18s +*a wqhye gp +*3m7cy what interaction could they occhc5yohqnh* **b+ sw+ 9g7bpasjiu1 m3 reqh8(ur? 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 cm;e gte+0ohj s7 .k9uare possible, and by what interaction could they occur? kesj;07m+h9 gotceu. 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 3z3gx4 ,i)szdc gg4)) tk nbtp$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak theory at ab0(( wy:fx /i/rvttys5j nboc 3out $10^{-18}\ \text{m}$. 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,. k,oybysr4b , Eq. 32-4, for producing a pion. sokb4b,y r y,.$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-valueal:ajll0mn) w, (66dw o6 dqfg 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 a2 w.z,y80i) p9q0fbal wcnere re there in a water molecule?    fermions

  A proton and an antiproton annihila.r -;ng fvg08r1rfm /mpnrz5p te each other at rest and produce two pions, 1zp rm-ffn5r .8mr/np;0rv g g$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distanc lfdu0x )a8qw(f-ju (oe 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 inldfg ,9m5i 9te terms of proper time, measured in a reference frame where the particle is at rest. If a tau li 9l9 gm,df5teepton 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 following wxf;cjq;. dqa*d.e*greactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model jf )wup/b wx5v x3.ojujwy+k f2+.rx2 to describe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of lv2t:-kh h *t fxzm8 s)m,*qwunight $c$ is the speed of a 7.0-TeV proton?