Give a reaction between two nucleons, similar t :k eil,r(,ycwo Eq. 32-4, that could produce a ykc:riw( ,,le $\pi^0$.

  If a proton is moving at very high speed, so n9.5mf g r0kqn x1jh9q/:z yfdthat its kinetic energy is much greater rk/01 nxzh.5qj g:fyf 9q9dmnthan 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 o: c in,k+4sc*ltk4xjtt6l ;lvf normal atoms, consist of? What might happen if v4;cltsllck: txitj ,* +46k nantimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay.tr m :bj5qh*4-vze.ty h7nx1g, pydf signals the electromagnetic interaction?

Does the presence of a neutri8lc (ek3r qp:.w5m :ytrn, q9xiid- clno among the decay products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak int qwii:t( kcyq,r5:p3l 8.-d9nmc elxr eraction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction evenx* dc /d/)wweg though the neutron and one of its decay products /)c egdd/w* wx(proton) are strongly interacting?

Which of the four int75fnskxyn( 8;. o-blnc.ovz teractions (strong, electromagnetic, weak, gravitational) does an electron take part in? A neutrino? A probs.(ynl-tc v ;7 fkx8n5zno o.ton?

Check that charge and baryon number are conserved in each of the d8ep 7cwf;s 4ionv(0o2zfji0s a-3thgecays in Table 32-2ang3j;otsofvif0 -czp 08e724hi (sw.

Which of the particle decays in Tw u2je)+zmj7i- owy z*e-q3pz able 32-2 occur via the electromagnetic interactionijjqe3 27yzp +--wz* wzmo)ue ?

Which of the particle decays in Table 32-2 occurlmbvt1yaa b 8te3u( k2e 9p01i by the weak interaction?

By what interaction, and why, does xqj ra13k*l0m 3gevmq oz8t9 -uu3 l u9yxbv/-$\Sigma^0$ 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 electromaj2y2zmd 01p zg gq)k2wgnetic interactimk1 2zp2 zgjqy 20gw)don?

Which of the particle decays in Table 32-4 occur b+,m1ld lntf8wx ek903ylc .iw y 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 mas rqna27pl/lfzi t6e u l;7v30qsless, had no color charge or electrical charge, and did not feel the ql2nl;e/63fv7 0upt z7rliaq weak force. Could you say that this particle even exists?

  Is it possible for a particle to be botfd3f*nllj / 5x7 rq+wkh
(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,1rf7jj-n85.ivw jx ho,r -xwd would it be possible to find particles made up of two quarks and no antiquarks? What about two vx.h -i,wfj jnrwd8 x15 rj7o-quarks and two antiquarks?

Why do neutrons decay when they are free but not when they are inside the nuclecmh7- 0 rzrxc eo;*o4huhoxom74;zr0 -hcr*ec s?

  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 whosepbw:kyw4ub9d 1aa ,r; kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-d+y q8: rc) uw76 ie,zupt:egnGeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which-.t +0q;vegslbt*xbc protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolu/vr rnk ,k ups40n vw.yy*1mb/tion for a very high-energy proton in the 1.0-km-radius rnps*vwuvnm 4r/y / y0b1.kk,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 of Example 0igv emfr k5wrm.ug,3 +s)vp- 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 dxcx+yw(0l6-b k *claz4,mbmu etails of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleon in a n,xb6bm a +uc*lx4lcm (yzw0k-ucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kV. How many revolutions do f 9mq g 1o7aqv-d,6t5a bfktxuv9x 4i6*fytw;protons make to reach a kinetitaqg q5f1vaoxw bv9 ;t4f-f tyd6i kxu697*,mc energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength fi1 n u87l6uzs($\lambda$, 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 acc3e )5ar k;(p80-nxce ndvtrwvv9hxl0elerate 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)s71iu-b u2kbvx27bxale/- nbd ya:u to house the magnets for the Large Hadron Collider (LHC) cab/exs 21 7b2)nu u:va-d 7ikyu-bblxalls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron7h bs:ay11 *u:csfr6a5ba u hp takes 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 :6 ssf b y*c5a1u:p 1haaubrh7given 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 particlkvz v ddzoe(z.i10 ::ee (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 Fermilab synchrot *s t mhchq(y/423yf .fur*)ld abd7chron for 1.0 fydhr 2 lh td/*.yf 4hmu*bc(3acsq)7-TeV protons? B =    T

  How much energy is relmg h dz*a*keen3ir +z7.b)( hoeased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy iim*iwot7jmpt-ugka7n9cd9 7 :99x h is released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutrons 8:s7*ys.f gqz7d tkel8)jgw pair?    MeV

  Estimate the range of the strong force if the mediating particle 962:tdu+liw em 5gwzv5uf d.v were the kaon instead oudl im65.eu+2tgv :f 5w9wzvdf the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading towarfio:dy ivazlue,ypj8ajx270 u7q:3 /d each other with equal speeds. What minimum kinetic energy mus:ivao, z7iqex7dfulp8/ u3 a:jjyy02 t 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 have if they are trav5h+b g5uy+6 yiez, dabpc,p;keling at the same spee;debi ,p b ph56 yyag5,zuk+c+d toward 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, givenvjmch 0*kz4 a: the masses of the W and Z particles as about 80hcmza4k * jv0: 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 27xop*p p n(haproton and antiproton o2h7 a* xpnpp(at rest 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 impoie lfxp402y1 s 0r3szassible for an isolated electron to raa2sfrs y3 e01z i4px0ldiate 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 wavelen)cy x0:hx sq,ugths of the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihilate head on? )c sh yqxx0:,u$\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 arp 6xk touqk5 /*y+8ojue possible? For those forbidden, explain wha5x* q o ykupokt8/u+6jt 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 kinetib1epfiam1f -n 23sz i w72)e3wzq2kljc energy of 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 energy of the electron in g +.9fbb hbz*67 stoefthe 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 widthh2n:bn 0 17au7on qhxi 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 t s.v0v xyaef2(he $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the 3u6)ii85wj ; fnfigqz$J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertaint9 iy)10ekf) u9wqgcy sy) 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 thatbgvrqz83ylx l9 8 v.6i are forbidden, explain whichl vgr 8ib. 8qxz6yl93v 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 combinations28x rf y0*t6xn tsla*s that can form (a) a neutron, (b) an antineutron, (c) af a8t*n*x r0s6yt2lsx $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations produce: j i wzl.k;)aq:jtekr) 9yq8)k+i fe4w(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 produc g7(hgykbn;u 4l 6txdhj+eqii(j4o6 4e 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. Below) for the reaction;sj d.. 4vkuxa+ayy.gkc x(v 7 vs..4 ;jdy.g xyk+a7uckxv (a$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the reactio y3,mkyheef 8zu2(2f fn $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a*cvib hflt2bymh 5.o9,0tn r ) proton whose kinetic energy is 25 GeV? What is its wavelength? b,9 obhrn mythic5t.)*2vf l 0
$\approx$    $ \ \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 Ftu1de /6,eygd brb3b2ermilab Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolut/,b6drugey2bdb 3 e1 tion, 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 electron and a positrok:052 iq+ t:7j espk0 xbpdvgon annihilate each othedk s52pg0b: epx0o+i vj kt7:qr? $E_{\text{total}}$=    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, k 3wrz/him,omrl,6gi-.;. donm / m gim8zl.vand by what interaction could they occur? For those forbidden, explain.rmi6go l.3/ 8z - m;igkmmnodi. /m,hzrl wv, 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 possfn9r5w d n).sfible, and by what interaction could theydf .)r95 fsnnw occur? 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;d-l. t, e5 vg4f6pqfnicej1(ip5hfu+q/vz t $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electrowe1trg9v0o9 8 feevt7s gak 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, w04a8h qvgbn2 for producing a pion. q04 gwa2 bvnh8$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reac-c121n p2ee, -c e(sbfkm gloction $\pi^- + p \to \Lambda^0 + K^0$ 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 f1p(w3mk q8s vl2s0quoermions are there in a water molecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two pionsm+ri08tfjz t. , 0ij8 zmr.t+f t$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification3 nt qni0in/;k 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 propo*a8hgrezcnw73 h5r/3bi8 v aer time, measured in a reference frame where the particle is at rest58rc7aibhrw/3azoveg3 8 n*h. If a tau lepton 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 paanlj )-,v2+rbo4ibp prticle in the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to +s;d.rxv hja0describe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of ligvow o3lkp/35rbym*f8v1byu v;b jq;1 ht $c$ is the speed of a 7.0-TeV proton?