Give a reaction between two nucleons, similar to Eqj+re4;.z dja f. 32-4, that could produce a ed. +; zjra4fj$\pi^0$.

  If a proton is moving at very high speed, so that its jz 8fq6km /fpw3 +yr;de;wxu 4kinetic energy is much greater than its restw/m;jf8 wzfk+3 rx6q4ypdu e ; 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 cons,(+ e+.c flonhzar0v:pm prh (tituents of normal atoms, consist+,m h0ocev( pnrlrfp+ ha( :.z of? What might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic interactinaa* x7e q4/ 8yl7r0h0wovqx ion?

Does the presence of a neutrino among the decay products of a pp4se togd. :6oarticle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a d.etos:p6og4neutrino? Explain.

Why is it that a neutron decays via the weak interactiony2tkc; vr:y;,* xunem2ax 1nj even though the neutron and one of *;xjxkn vn2r,y atu;m21 y :ceits decay products (proton) are strongly interacting?

Which of the four interactions (st2;nwhob5 0sq .r hc/ejrong, electromagnetic, weak, gravitational) does an electron take part in? A neutrinhoq; 5s/2c0nr j h.wbeo? A proton?

Check that charge and syvl;/by3v8,bm3u4 m r3qbtd baryon number are conserved in each of the decays in Table 32-2 8 vytl;43dumbqv,b/3mb3 sy r.

Which of the particle decays in Table k(.if(3 upzaq32-2 occur via the electromagnetic interaction(uzi 3fa q.p(k?

Which of the particle decays i0u;rn; evbqi6+ns hde7m9.pt n Table 32-2 occur by the weak interaction?

By what interaction, and why, :ppa kwk,*;2on..r 1t djczv:2pe hqfdoes $\Sigma^0$ 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 d r(x(z3o0 k-t. gsuzgq6kd1jv ecays in Table 32-4 occur via the electromagnetic interac sq1.u(z0rkgo( g3 xdz-vt6jktion?

Which of the particle decays in Table 32-4 occur by the-t0 zi/tkgdd* o,bkv3 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" thatsfp0+i7 rd4plq9,t 9y8moks bkw0l, q was massless, had no color charge or electrils4qfop,q w dys 8l+m9,0k0t7i pbkr9cal charge, and did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to be bot1xaml yc49p dwb7 1:u,uq3xmch
(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 ityjltc n1 rj) d p-y5-dty7(9oi0 nqci. be possible to find particles made up of two quarks and no antiquarks? What about two quarks and two antiqtic y7-y o l.n1)ij0jtqrny5d dc-p9(uarks?

Why do neutrons decay when they are free but not when they are inside te3bnhr 7k 0;;rqdyi:b-qh/ :py)m uvd)egqg ) he nucleus7yuh;)d:hvq;qr:e 0pr i)b b/-qmgnd)3eygk?

  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 5xy egn9,7 fhiis 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons. E v/mq :iofq2k63weo-s gjlb-+=    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field isf4zdcuh* 6nz + k;9zlb 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 revolut 2b3al09 tog-(2) w usr3v,dkl lyctvbion for a very high-energy proton in the 1.0-km-radius Fermilab acceleratoryb2 0 ,t)2a9 bl(v rwlv-dk3 tcgl3ous? 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 ova90/fe f// zu) m.ws*f 80h(m aqvdfkeudr:uf 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 oy2rpuzr k::47, r udhparticles or 30-MeV protons? Compare each of their pu:zoh,u 4y7k2r r: rdwavelengths with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees76)i86siys l8f wbf gl of a cyclotron is 55 kV. How many revolutions do protons make to reach a kineti l b68g6 )fif8yis7lwsc energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (jn1q:1 /3j7zjrifm*ahr ru,o $\lambda$, 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 accgcflm;d.yq2teq 1k- mq 6q .a,o(5xmkelerate 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 hour ;. px5:nlxygse the magnets for the Large Hadron Collider (LHC) calls fon .r;:gx 5yxplr proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron tak* eec fjgn -+e7yvcoq1b8v.3kes about 20 seconds 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 vje1f*cn3 yc-q koee.b+8vg7protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of njc ,yed8c 2p+l-4hjwm -e nz3a particle (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 Ferm4(kjmc ;n- yo uhmz8f;ilab synchrotron for 1yjo; 4n-mcu(km8z ;f h.0-TeV protons? B =    T

  How much energy is reledgu,wrz3x.-0llyk ttw . )w s.ased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is releas1avc6a rmw* 8 .7i2hjb3x2jfjf i9q msed when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron pair? xj7mfl jch:v c4u )5m1    MeV

  Estimate the range of the strong force if the mediating partitaf ws p 8q5esn u2m5q0c;(/wscle were the kaon in0 ew5naptmsc5s 8 q;qf2uws/ (stead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward eac*avxxegktde1loxw i( 591wih *v66t /h other with equal speeds. What minimum kinetic energ odx6ew61 vgixexwtk95ihl (*/a 1vt *y 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 /1zacyzv- 4 z+vx6lcktwo neutrons each have if they are traveling at the same speed toward/kzz6lvxy -v4cc z +1a 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 masxy +n8ax6kjgb++x 0c;w3 w y/phplm6vses of the W and Zvhayw +xcxglx3jwk p / 0+;b6mp8yn6 + 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 produced when a proton and anq bv;49 o4ybqbtiproton at rest annihilate? 9yob4 b;b v4qq $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 isolated melpn1.9r lix *4cj1c electron to radiate only a single photon. (b) With this result in mind, how can you defend the phot imlx4pjc9*.clr11e non exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produced when an electron an sz* t8+x. bk,aklgx2rd a positron, eack2,8trlaxbz.*gs k x+ h with 420 keV 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 decays are possib* p2 5pdklt5zgle? For those forbidden, explain what laws adlp5kz5g tp *2re 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 in the6sz:pqz f:8vk 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 oqnml8wwj4hn;72 j:nk k+uo8 af 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 egc ax; kj t7b10k.s8mz51iuxp71tgae nergy 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 the:plf;fckb8 +pjk3;-r obtqn; $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of dpv,dbb,gx gq 9i3n sj ),altxw2 ,41sthe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) ofwcw3c . h5yl9wu*:j yj7/ owdf
(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 posv-.l/r g(ten :xk9h tusible? For those that are forbidden, explaiv.knlu r9 te (-/:thgxn which laws are 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) an antineutron,8fjr.2i4s s;o2 xp pqzpsix8 r4 ;zjsfq .2p2o (c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations qfd sveqha( 05g5a+w- 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 4ie;ddo: ruxir*p (a. 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 Feynm.,ah*eitak3ky/0 n dm an diagram using quarks (as in Fig. Below) for the reaction kih.k 0ym /ted*aa,n3$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the reac-y v4pcqb36rstion $n + \nu_\mu \to p + \mu^-$.

  What is the total ene 0r:vma pz pdw/idmt6+8s+fm*rgy of a proton whose kinetic energy is 25 GeV? What is its wd6tisp+mv+0 *: adm 8p/mw fzravelength?
$\approx$    $ \ \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-1dzp;h) z/;m71y v rt1gr ubkmradius Fermilab Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and approximately how long does it take fvbpr 1 ym;dk )r1z1tgz /u7h;mor them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released whenqye 7i0- fs +mvwv,k 45bkmzjg13(cyo an electron and a positron annihilate each oth,f(j msqg1- vyw7 4kmvkyi+ecb o5z03er? $E_{\text{total}}$=    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 followinz0n 8cb7 jjlh9g reactions are possible, and by what interaction could they occur? For thosebl8z90 jc 7hjn 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 co1s fq.*86xs* nfpyy x5djm.bhuld they occur? For those forbidden js8pdy 5*.sb 1yqh.x*fn 6fmx, 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 aq 6eqetw7 */tk $\pi^+$ 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 ac1pagmttm+frw16 w2; t 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 r9.s+rrmkh aq*t7 0aj o2i 1znneactions, Eq. 32-4, for producing a pion. *raj9t rnq.1 him2zo0a7+k s n $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-valuk*ay , dn7x,lke 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 fermya)/vinwzuj e/s s :a:qd-(z;ions are there in a water molecule?    fermions

  A proton and an antiproton annihilan3 3q).q,gkjqdw 8a3 ft/blwdte each other at rest and produce two pions, w3da ,/ fbtk dqgjw3q. )3lnq8$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so6jk639w0j. n0c c hhm6o efdmo-called 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 )p4ca)lcb)u c,+bpo ta reference frame where the particle is at rest. If a tau lepton is created with a kinetic energy +4)bca)lbp)c, c puto 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 n ) e5spk68yezparticle in the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the4srt9qdc t6: kqrr *k+ reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of;mz02 z4aeclb +t6 jgi light $c$ is the speed of a 7.0-TeV proton?