Give a reaction between twmw7o)n* 95bpdl uxkf y y a+jb-;s+9tno nucleons, similar to Eq. 32-4, that could produce a apny; l 5b*u9bxw-jo7fdst)+km+ 9ny $\pi^0$.

  If a proton is moving at very high speed, so thab:;2f 3c lz336hvnbb qx r1smft its kinetic energy is much greater than its rest energlq v3fs2 ;6chmfbx3nb13:bzr y ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made 0p5;g)zr q2 ta/ag pjd/zt.djup of the antiparticles to the constituents of normal atoms, consist pa .zqdgj ) ra;dt j5t0//2pgzof? What might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decauf5 a-f y7 5r acv/rx 1m;q/a0fx8xhsey signals the electromagnetic interaction?

Does the presence of a neutrino among the decay products of a particle necessari, 2toak fhksbmh+c0* 2 w,msg0ly me g2,0,mhk cwa bs2mkts f0ho*+an that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron d7t mhd2z eliinww9 6 1+//jjoxecays via the weak interaction even though the neutron ann e h+wx61ml2z7td j/i/ow9jid one of its decay products (proton) are strongly interacting?

Which of the four intbx /l 8eyz2:sqn4ct)k a kix2.jn3xr+eractions (strong, electromagnetic, weak, gravitational) does y4se:tqlxr.)akjbzcx2 2in8 k+n x3/an electron take part in? A neutrino? A proton?

Check that charge and baryon number are onkcelj gd g6qv7 p*+ft.6 4a2conserved in each of the decays in Table 3g 4acl*+fnpjq27kt. 6 d 6vego2-2.

Which of the particle decays in Table 32-2 occur via theksg+rpw)v3 /n efe7f( electromagnetic interacne)37e+krfwfg v(s /ption?

Which of the particle decays in Table 32-2 occa srj so:a7)n8ur by the weak interaction?

By what interaction, and whyc2gcjkm8..ol- dd) eboa 0,rl, 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 Tabljm99;toko3 r ye 32-4 occur via the electromagnetic interaction?mo3 oyj 9k;tr9

Which of the particle decays 4vc;o0 f(zx +yrn./mavt 8nc;tn ky t: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 5i*.qptj q aj1a og0w91tzr3u of "neutrinolet" that was massless, had no color charge or electrical charge, and did not feel the weak force. Could you say that this particl9j *t g 5ziq.aota1wq0 jru3p1e even exists?

  Is it possible for a partic-z.jd*v/h i 8tc;.kqr xazea8le 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 pcu *p yiq(i,hmw gcza),d :x50,gdie :ossible to find particles made up of two quarks and no antiquarks? What aboutiezya d,:g,*qimc g,i(c)w:u0d 5xhp two quarks and two antiquarks?

Why do neutrons decay when they are free b* 4 yr/fk i9-dbd1+3omytqjc mut not when they are inside the nucleus?bm+-9cfo rqk1i4dy/yd 3*mtj

  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 energyatr y9p 9lpq+6t 3w0c 7wb(ycq is 6.35 GeV?    GeV

  Calculate the wavelength of 35-Ge ucclv -,q: v)) lgw0md+tstplmd m05-V electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which prot:5b lo: . wkn6vo7z.vz 5rczesons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very high-ener 9 sbys+f nelokn+nd:,q-k ,;sgy proton in the 1.0-km-rady9 ,ssno+efdkn nq,k+l;- :sbius Fermilab 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 oe1-pb iz77y us w,l3 j,ie. le,s8uxqyf Example 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 particq;n s 2o(fzk;gles or 30-MeV protons? Compare each offn;q;g 2(k szo their wavelengths with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclot(h(*bb xa6hxau-f m lq.)p8ttron is 55 kV. How many revolutions do protons make to reach a kinetic energy of ph tx(f- .)bahqub6alm*t8 (x 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (ljs ui-/8 a4ypv43lxf$\lambda$, 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 deutero4b.3f 35gzitzgiw - v3rdmx3 pns ($^2\text{H}$, 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 Large nbdb )ab*b4t pxri2a6ke; + /c;jfg6bHadron Collxcr/4abf6bn6 k*iga2+ db je)btb;p;ider (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 secondvw):j3 zy,x52 pdsn0 4 jvznoes to bring the energies of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once per turn. Estimate the energy given to the protons on each turn. (You can assume that the speed of the z n:ojd0yvsjpx4zn2),v ew35protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particle / uypgd a:4rk3zep; f6(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 atsc ) gz0z;6uot the 1.0-km-radius Fermilab synchrotron for g 0)z6;ozustc 1.0-TeV protons? B =    T

  How much energy is relea 0y*zd:*7a9jlusbncf s:bt,q sed in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released wil*q2 f ;p,ofzhen a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is requis/2g/ll: 19i7p itnix pb/xu ered to produce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particle weaxriwc4l *lh)u t1;6.w9 qw/o1 vlzx rre the kaon insx.wwqi6thu l * la)rlw;rv41 zx/o19c tead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with 7 qdkyl4wm.cr8 es)*oequal speeds. What minimum kinetic energy must eaowks4lqm eyc8)r*.d7 ch 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 q vv+y;ga4(tadvn:9; jwi f5c each have if they are traveling at the same speed tow:ad+5fjvvctn vq( 4ag9y; w;i ard 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-ru yqm(6ufj l67ylie(7,goa using Eq. 32-3, given the masses of the W and6ru -qjygoull6 i7 (y(,mfa7 e Z particles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons prodh1l pm3e svdj/yv-ynqt1*)*ayo 7i 2puced when a proton and antiproton at rh 7vi*ydmjy/ep atlspq*12n o1)v-y 3est 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 +h2wa+ qku1lian isolated electron to radiat1i q+kwhla+2u e only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produced when an elect9o n8heeth/a4 .z4mqn ron and a positron, each with 420 keVoth /eq8.h9mn4n 4ez a of 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 decaysy n orso*s 7b-wb )/gulbzfbk0s*p352 are possible? For those forbidden, explain what laws are violated.o */bfbl)-z2r okpssn3syw*bb 7u5 g0
(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 proq ,e vp )zfn)h;(rehdj 1wxhn.g/*-kzducts 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 enj*j8 qaq+put(thg /; lfer.-jergy 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 ypnwy3h 33nr-l,0. oc yfrs+rthen the lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of thy4b6*c f w maqdl-p0o,e $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of thet 0 z2q/, ohq/t0dyql5dwdp3u $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or u ny0a1nuv --l gmxdx6*ncertainty) 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, explai1z lg*e 9ht.xjn which laws are jz.el1*g h9x tviolated.
(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 anto.e 1 29lqcua8eqst gtir**n3ineutron, (q.g oi t*se c3a*ue1lr9 q2nt8c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations prra/*z,s dukj)oduce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination needed to7x /zsnw1pb b seyzc)8tvw1tow2h:6 . 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. Belowm;snt whj3n(5ar /j 8d6mel6c) for the reaction 63adlsj;nm(r8n5w /chejm6 t$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the reacl)t.lwwk6w k1sef p9,tion $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton wu/ggyd u7 bi1b/ nn(o1hose kinetic energy is 25 GeV? What is its 7/ugbnyg1noi/u1b( d wavelength?
$\approx$    $ \ \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 Fermill l* aimbv fti7j6((1dab Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and am(d l6j ba1(*vil7itfpproximately 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 ) rl m hm0cp,do;shrx/kv9+:w when an electron and a positron annihilate each os: l0hr ,cx; +w9vo)mrdkpm/hther? $E_{\text{total}}$=    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 intera/;iz69mh ry 1flchz hlj(p6e5:yzl o+ ction could they occuf 1m;h zzo/chrl66eh yizl :p5l+(y9jr? 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 are possible, and by what interactksd8ka58ez)rx2/0;3 j bab yordik r.2 i2izmion could they occur? For those;. iebizo2j3xr/ mbkr 2zk0d8 )kai r8 y25sda 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 arx1 wo44e2 yqn $\pi^+$ 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 atmv ;7dp.q;s sl z1f/ng 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, fr)71 htwunj ( yk 0zqi)0c8d*i0otwwwor producing a pion. i)ww (rohqwwyktn 1jdzcu0t)*0 0 8i7 $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for tv cfpi..+ulk8he 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 ther7n7bjk5;sc mr e in a water molecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two pion) fy0.w+uqba1ciz 3q ol.k-cl n(dsh;s, ;l lfyiquch1 -+0an .q(.s 3kozb )wcd$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distancea.7otk jkha 3+ 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 Tablgvg 2 lelz9,9c :/gau:x,jmh ee 32-2 are in terms of proper 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, o hallej9gmg:cg/ v,9, :uzxe2n average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in igmll9(mv7p -)mp y+wthe following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the reacsvr4dla 9g0 x9sco; uah9,8du fq/8cntion $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of l (fexnro +xv+(ight $c$ is the speed of a 7.0-TeV proton?