Give a reaction between zwq1lj)eax+h :3nn z9two nucleons, similar to Eq. 32-4, that could produce a zn :hq1 3xn)a+jze9lw$\pi^0$.

  If a proton is moving at very high speed, so that its kinetic energy is much gvc9o;fi aicqm-w h oq8,/ ak2,l,iqd-reater than its rest energy (8dc,vwlii,/ q9qmq,a;ihc-o-o2f a k $mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticles to the constituuaes( t o-6)ufents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with our normal world of mtu sea-6)f u(oatter?

What particle in a decay signals the electromagnetic interovqjy14q i-.u)g: c dzaction?

Does the presence of a neutrino among the decay products o 9hbg,r5dj c-ml*z bb-f a particle necessarib-59hbgljmbr,-z * cd ly mean 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 decays via the 5pdjlq192ymsil, h4wweak interaction even though the neutron and one of its decay products (proton) are strongly interactidilm 2ps9w1 5hjyl 4q,ng?

Which of the four interactions (strong c n .( xbxhfet-z(3nvkj159na, electromagnetic, weak, gravitational) does an electron take part in? A neutrino? A proto5-9axz(3fhbnc(nk1 .jtxn v en?

Check that charge and baryon number are conserved in eac)bj3* bkmkw6ch of the decays in Table 32-2 6b)*bmk wjc3k.

Which of the particle decays in Table 32-2 occur via the electromagneti-42pspcf h ,ba;gvn-jky 1pk- c interactk-kn c,hg2j-4pv f 1abpysp ;-ion?

Which of the particle decays in Table 32-2 o-mg/p**mob 6br fb:i w3 2gnbsccur by the weak interaction?

By what interaction, andctogv:3ni)k- m kr)s2 why, 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 electro ctnn2ay k+i):magnetic interactionacknt y:2+ in)?

Which of the particle 2tg+ 3xt7)x-b yfz8 ceiyr,ty decays 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 "neutrinolet" that was xm0 ghe tt)58tmassless, had no color charge or electrical charge, and did)ex 5httm08gt not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle tu 0 c1u 0ri1cq0k-uq dd61qfaro 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 quan6i 9+z+o grepx6a:fmwq gz9:wtum chromodynamics, would it be possible to find particles made up of two quarks and no antiquarks? What about two quarks a q9xo m6wafp9i g +:r+:6gzweznd two antiquarks?

Why do neutrons decay when they are free but not when they a9zzcv vqb m( jk0/0kn/re inside the nucleu/jb(qvz 0ckzv/m9 k n0s?

  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 kinet 0f-tqbiifg 72 (gd;0fzzn2cvic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV elhf 2z0r hr3km0ectrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protons make d8od2-xnoxrj//ry(r h7srk; $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one compleg683hjqyce5j l5aa(y5ccb/m ai /u u0te revolution for a very high-energy proton in the 1.0-km-radius Fermilab accelerator? ycehq5/ac/ aim j b5a630jglu c(u5y8 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 accelemg )jo2vp4 t4q yy:co4rated $\alpha$ 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 h7qu /f/(4w iam: cx5jt 1nsjs1./qwmcv/ jvtalpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleons/1sjwvq.47f tqu m1 xmaiv/:(5jh//ncc jt w in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cynr 0b;96 uu cgex4ok4mclotron is 55 kV. How many revolutions do protons make to reach a kinetic 4o4c;6x0b nuk9g erumenergy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (ap46d7gpzoei:8j pb bb 2-b4q $\lambda$, 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 deup* d;y;;gcxks/ o,07fy,qco w n,v txaterons ($^2\text{H}$, 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 tu)*zyb bbpuk9pb,tf6bra236o u y 5p1vnnel that will be used to house the magnets for the Large Hadron Collider (LHC) calls for proton9 oyypbbpf65p1 )z6 br2vukbub at,3* beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes4xfylx8nuqq* 5v z0 zvl-r+o8 fb i+3h 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 oqlzuob 3+q+yz-4lfx5fxr i 08 v 8v*hnn 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 paw5wk xrlt5 b51rticle (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-bi3w q xm .p6dfrk0d-5-t9hq skm-radius Fermilab synchrotron for 1.0-TeVt5-q0swr p qbx-dd.i fh3 k96m protons? B =    T

  How much energy is released in the d-llx ufh2b 1uhcgywwqs25q 9r 3:0l j3ecay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released whg-(o 7zt kf ph. o-lss:jav0ju/ cd2u0en a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutroxvnnoy-c (i-5n-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particle web n/o* tpor;,sqf(mk+re the kaon instead of the pionq /fob +*s( rn,mk;tpo. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other wr9+pg v4dp z yonw)zke+, ca;,ith equal speeds. What minimum kinetic energy mu+epk a d vy,wn; r4+)g,9pozczst each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic enert23: yex xpg gm8x+ha,gy must two neutrons each have if they are traveling at the same speed toward eacxtp aghyx+ g,e:3mx 82h other, collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the w1nvfqw2ikk n-( 9pwf+eak force using Eq. 32-3, given the masses of the W and Z particles as about nipfkkvw 9+1fw n-q( 280 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced when nz +;om;1ru0hzhdd; ma proton and antiproton at rest annihilate? d+dhz;mh1nm;; zour0 $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 a h 2-6fl yde4mb8-m7t(hewwcdn isolated electron to radiate only a single photo weyh -dbelt(8 h2m4fdwm76-c n. (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 electron and zv/ h ekzkww;b3+)gjgf),li 2c0e9qt a positron, each wkt w;03z) eh+,webcqf2gzj gk )ivl/9ith 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 reactiomf783ovalbjykz4 ;: a ns and decays are possible? For those forbidden, explain what laws abzf3y :7oav4 km;a8jl re 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 products7gx lgw,d3 qb-r-h h/m 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 50 fum(st9zqpl:nb wzbo6;i6yq x *2e 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 then the lifeti ous5v/j1 uxpm4 3azh2me of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of . yf65 qe*rrczthe $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the 0 t)- pbb ym,6e:fqrmlr gb.-g$J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy w rpz85aowu lp8 fo6,:9hrw .uuidth (or uncertainty) 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 possib/g0aa)o g )e;.jd5ueoihn-h dpm7 f1dle? For those that are forbidden, explain which laws are violatefnd) da)5.hoe 7gm 1p-oeg;dh j au/i0d.
(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 antinw 3:j4 a ze6;1jdp +ohzp;hgvreutron, (c) a h+ad;pj346:zejwo rv1zh;pg$\pi^+$, (d) a $K^-$?

What particles do the following quark comkamjt7:4 f4d6le x bs+binations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination neeacoo ;tr3+ w,vs*wrd9ded to 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 9 5 :nghxqnyx5w8x2y,fuh +wh(as in Fig. Below) for the reaction xhw55uw+y yghn92xfxhq n :8,$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the m,vq3g ,wfs6c8lf+z freaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kin1xirosniog / z n e1m/i+lh1-6etic energy is 25 GeV? What is its waveln 1r-zo h+iile/sm xg61i /on1ength?
$\approx$    $ \ \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-radixgi65ab*it- 1foj;ox 2ii7o cus Fermilab Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, 5;7boo 2j-i1f i tx icgox6*aihow 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 annihipkm;ebroo;zl ) ;-t9 elate each ot r;lo; ekbez-m)o;9 pther? $E_{\text{total}}$=    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 posii7rl vrxo82: gl mdi4)d o;8asible, and by what interaction could they occur? For those forbidden, explain why. g 8)o4xdiov:2r7 i ;rdl8mial
(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 : 9s;ufuth6nzw-9q s gpossible, and by what interaction could they occur? For those forbidden, explain why6 s;hnzu f-9wg9 :tsqu.
(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 a6m / u i 5hmr4g3/ii;w*mnjgcx $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak theod i a*qd*7tny 1nz/-zzry 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 myw: aq7r/t,c1o+ qhr3dc v9zeach of the reactions, Eq. 32-4, for producing a pion. trvhqw d 1q7yr+c,oc39/a:zm $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reactioaq (pthok-/ h;n $\pi^- + p \to \Lambda^0 + K^0$ 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 the7lv(nv,v 3a 8xe8.z0muxz kz rtz 7*cjre in a water molecule?    fermions

  A proton and an antiproton annihilate each other at rest and prod.8jb r1ms. a,+qea hebuce two pions, qjhm.. esar,b1+a8b e $\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called uni 5urct,9yff8d : 2f7 msst-rddfication 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 7 pu8hg(6c8gd ltju9r wl)dx1 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 trax1dr tju (g8hlpdg7 )8c6lwu9ck 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 folz/wpc/e 2 uih9lowing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe t 3 sto;d u2llr(vjie,i.fl* 8ohe reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the spe ,pob.ut+:ec ted of light $c$ is the speed of a 7.0-TeV proton?