Give a reaction between two nucleons, simj2og.ms*hzvu* fyj aum m1;)j7.u. go ilar to Eq. 32-4, that could produce a j 7.msoy*m v1mhg u.j)ag*zj.2;fu uo$\pi^0$.

  If a proton is moving at very high speed, so that its kinetic energy is much grey57my:d3vm k nateyny:d5m v 7m3kr 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 constitu rqxkm ,hd0+q8juwm(1ents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with d+j hr,(1u0kqwqm8xm our normal world of matter?

What particle in a decay signals the electromagnetic interav0mph:p89qxs ; i k8lnction?

Does the presence of a neutrino among the decay products ofrwz th)9;m; dv a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrvhr w;;m9)t zdino? Explain.

Why is it that a neutron decays via the weak i gqehwhf 41,st)/ em5a*(w,dpr mxe1o hzvx10nteraction even though the neutron and one of its decay prwef1/he 15r 1te *pdv z)wgxsx0qo,hm(ma4,h oducts (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, gravitational) dtuex.hqdgr n2)70 e8does an elec7tq8un.g d0ex)herd 2tron take part in? A neutrino? A proton?

Check that charge and baryon number are conserved in each wwgl)yi* * 7v)*i+dawosxzko ..0 sojof the decays in Tabledx oo slw7*si*0+)a) y*gkw .o vjziw. 32-2.

Which of the particle decays in Table 32-2 occur via the electromagnetic interavx mww1dsho9.aj u+)qchyf69 zr(, k1ction? 9,6yw1xs9 f)cjv(wrd+ 1ozauh . kmhq

Which of the particle decays in Table 32-2 occur by the weak interactec:pnm3*6 ls8: csi ewc)9asq ion?

By what interaction, and why, s) mcpy k:y;4ix youxsuj4*3)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 electromagnku k1ugg ij tan,tys6-;,79ndetic interacn9k,tk6ujd-; ,1 giu7n t gsaytion?

Which of the particle decays in v xb our)r2dzf;6*) ppTable 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 z i2/qie)qb o,of "neutrinolet" that was massless, had no color charge or electrical charge, and did not feel the weak force. Could you say thatiize )2o/bq, q this particle even exists?

  Is it possible for a particle to be boevaj * -nt4oe,th
(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 chromodyn .jo-vsh6g + rit4udjvt8z/y 7)6n rwdamics, would it be possible to find particles made up7njj)hztvow8u 4/d. g6-r6rvt dy+is of two quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay w4 -+wzfg khl5ohen they are free but not when they are inside the nucleus?w 4ozgl-+h f5k

  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 p.is ;d27rgjza roton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength o(tnal n .zctjf 6:64 rjny,8rbf 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is us+xc8lxpt s/pa4fh5gv: azy.j gl2jh. j(/e 4bed in a cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for 1 nnsx+,;p -zxd,dbcs7 ffac. one complete revolution for a very high-energy proton in the 1.0-kap zn c,1+s- .c;,sx7dfbdfnxm-radius 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 Examilt1v5b9fez ; ple 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 ou (g6e1z*sprp it details of the nucleus: 30-MeV alpha particles or 30-MeV proto si( rg61*ezppns? Compare each of their wavelengths with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kV. How ,p )h-ka o4ao(vle3 ,wb rv 5bhuz9ns2many revolutions do protons make to reach a kinetic energy of ask,za,() l5 h2opeb hnw9vo3 4vurb -25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength e1yxaty: q49k($\lambda$, 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 7k,i3h x-y1hdpl xrt8deuterons ($^2\text{H}$, 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 tj-n ,p *aoxdf5/ 2h douv;t;geunnel that will be used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.etujadhfx/* g;ovd2p;-o, 5 n 0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds to brg; v0grbvkd,p3: ocag)57ndm ing 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 assumr0: v dmac7onb)3g gvg;kpd ,5e that the speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particlewtq00eb,z;g3(l,eynv )kl 7gv6baez (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 intensitybr/0,qt:yxgs j+z x i8 is needed at the 1.0-km-radius Fermilab synchrotron for 1.0-TeV protonssj gtibzq+8 x /ry,0:x? B =    T

  How much energy is released inpyl . 2x+ o: v3cvks(ismwrjbw49l.u. the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released whefk3z .iy1 l/kgn a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutr fpep+f9 up44mbvmd+ 8qe1 -wf 0h,firon pair?    MeV

  Estimate the range of the strong force if thehvhs h8m+ta c:2/el2kr-y*ogdm nzx ;,c* oy , mediating particle were the kaon instead of the pinz/m2g8oxsh roek m* ldhc- * +yt,ch,va:y2;on. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal s6kv/j; u9me ir8 x7sydpeeds. What minimum kinetic energy muvi8skd /rj;y76u 9mx est 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 gh9dx.z 6)qo vvq*wcd. tt5 .gare traveling at the same speed toward wqv.ht.* 5gxdoc 6 )9vgtd qz.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 massecrih) /x0- p0tn yu3uuys.yi,s of the W ap-iy i3.u/0u0uc synrtxy)h,nd 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 phox.k74fygq. so tons produced when a proton and antiproton at rest annihilate? 4s.f.gqok xy7$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 pjs w,79v(o/zd p/nuh energy, that it is impossible for an isolated electruz,ws9d jp7ph /n(/ voon to radiate 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 photon.5uhybzf1zgrx3-y a( s produced when an electron and a positr(a1g y bzuhzf3xy.5r -on, each 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 ( hlx/9xa ztnpxq e+owd98 d+6possible? For those forbidden, expl8h oeqz(atw+9 pldxx9 / 6xdn+ain 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 energ,t xo gs)ji z6n8l5zu4y 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 5 0 93 uzendud,qr/jgyenergy 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 then the wa+bd (0 .:egna4emx vlifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of thendgwl 1,fa/;o $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of th no9jl l,l6me.bd7hf v0j06 wfe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uyj ,2uuncb(d2 mcdl; 2ncertainty) 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 aref pjg2u;fg x.8 forbidden, explain which laws are v;f2j.g f xpu8giolated.
(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) 3ekw0+iztwi3 nq a u,h o1ld*1an antineutron, (c) a3k1a*0winhlt 3dz i q+ ,w1euo $\pi^+$, (d) a $K^-$?

What particles do the following quarge0 o/(vi, os*uqplw3 (n ka9mk combinations 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 produce - ne :ztv:ip.*9vq 1gbint5uda $D^+$ 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/jc8 ed)j,lo m diagram using quarks (as in Fig. Below) for the reactionm8) ,/ oeljdcj $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the re r1mtpcdn59ewd i:d2.z qy8 venb v0(0action $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? Whahgwml00h 37q(bb /+jhplutpt+ ; 9gfq t is its wavele g70jwpl0f mhh+3/tt (h+g lqp9;bqu bngth?
$\approx$    $ \ \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 wix.n8 3wpq*hktth an energy of 150 GeV. If they are accelerated by 2.5 MV eax3qkh. *8ntpwch 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 y18;9tl1c b4rbv pm w in)d.jpelectron and a positron annihilate each otherimbpc4t1j ;wl. pb1nv8y r)9d? $E_{\text{total}}$=    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 followingqqm:1bbx.u dcm0 h 8*c reactions are possible, and by what interaction could they occur8*m1qqx.0bd cc :h bmu? 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 reactvr6mb 1 mpvh-9ions are possible, and by what interaction could they occur? For those forbidden, explainbvm-6 pr 9m1vh 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 aq9k rcz+mk3u5qcn5 gez +6/f$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs iss1g 5h *(m nkkwl2bz s-yr;i1n the electroweak 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 o2ej7vggs0. 1e1 hdhkk f the reactions, Eq. 32-4, for producing a pion. sh 0ggjhv.1d7e1k e2k $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for thewxmb,f5 (t 8ao ) 1qpdu0i2lr ;wicv7yix3k+ v 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 there in a water mlw- cl capeh9ig 2j.2 nf,*b9iolecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce dayhvat m* 9hub7:/5otwo pions, y7mvahhot5 u/9 :db*a$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distan+z5g):jndovn/z. bplea 81f lce 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 ofbgaa qs hao .q1.4b2l+ yx;3nn proper time, measured in a reference frame where the particle is at rest. If a tau lepton is creat 2+ .q;q b o3x.al1an4ghnabysed 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 followgx rnpdo1;j/1 ing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the react04c f gx 7i3p0iqsdnyh )..qozion $p + n \to \pi^+ + \pi^-$.

What fraction of the spef cm ap*o5qv68v,0 b u7ymong(ed of light $c$ is the speed of a 7.0-TeV proton?