Give a reaction between two nucleons, similar to Eq/uzw3l q;0c0 exe0u3w *pvrkh . 32-4, that could produce a *cvq3e00lp/zwuk 0 xhru; 3ew $\pi^0$.

  If a proton is moving sans7 9tr-sp1*d ( qi:a6dp qoat very high speed, so that its kinetic energy is much greater thao6ad-sq(*n9tsp17psi a :rq dn 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 thp w-fl,c7l, l(qjw3j q 9cu.qae antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made ou-c ,qj 3cfw.laq wlpj ,q7(l9f such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic interaction?g -e15b/+m( / igkh 2dcoblpcg

Does the presence of a neutrino among the decay products of a particle necesszt7y:p6 1.fc-li ymf darily mean that them :yp6z 7.y- ciftdf1l decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays viavh; /aep: ynqun7 d9fcirv2,( the weak interaction even though the neutron and one of its decay products (proton) are strongly iy cf/e d9rpinvu ahn2(7,vq;:nteracting?

Which of the four interactions (s 1qnxe 70j+wbwtrong, electromagnetic, weak, gravitational) does an electron take part in? A neejw07w q+nbx 1utrino? A proton?

Check that charge and baryon number are conserved in each of : hm77tujjssu1ms 66kthe decays in Table 7 mjk6s s7:tjh6u ums132-2.

Which of the particle decays in Table 32-2 occurcvu v08xs:g f/7 7a;bs9mzggs via the electromagnetic interacti0sab:gsg sv/u79 f;xg mcv87zon?

Which of the particle decays in Table 32-2o;gw/j8no .kawnk d 2; occur by the weak interaction?

By what interaction, and why, d ;8xbnmaox0r(teaf2:p)z s0 woes $\Sigma^0$ 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 electromaxvu l;1 gg*+jugnetic interacti+1xug g*ljv; uon?

Which of the particle decays in Table 32-4 occur by t:vp0j 7vycnm+av*z- hm u)r 9jhe 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 masslesex;jt5d7ck; rv3bt ,x s, had no color charge or electrical charge, andxb,7tket3;5;d cxvr j did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a bz:dz8 7huo(rbzan* 1 particle 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 possible to find paraks 1: 5h.et2 a5c26seokrccsticles made up of twosksc kec.t2o c15h2 er65aas: quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when they are mpu0mp 6mv991nrf*f c inside the nucleusmpm rcf9u 9n pmfv0*61?

  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 is 6.35 Gd(i l e/on6x* -j+ p1rrzdev43.d euhyeV?    GeV

  Calculate the wavelength of 35-GeV electkq bs7kzva 01b (nkc4(rons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is usexs 28ag 03 s5w*7ptcuxpasss-d in a cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one coxjp3ge7 e s-bb* )l9abmplete revolution for a very high-energy proton in the 1.0-km-radius Fermilab accelerator? T g*p3ee7 )lj9b-xab s b=     $ \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 Example4q ig-uh87 dq*f0cy kd 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 1cz7h:d9rb(be/fe*zzwi(aa alpha particles or 30-MeV protons? Compare each of their w7*ef: i we(c/rdh(zz 1 9baazbavelengths 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 many 31vrbd lob/h-revolutions do protons make to blrov-b 3/1 hdreach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengthlsz0;vi9)f h p ($\lambda$, 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 deutks.q3qizeubh; ei/a;g /6* pzerons ($^2\text{H}$, 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 *ebn96v my8j;usvtc- used to house the magnets for the Large Hadron Collider (LHC) calls for proton vsmbt*yn vj6;89-cu ebeams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron taj 0l -6jxxc9int /ps9lkes 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. E9ijctxj 0/sl x96- pnlstimate the energy given 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 ofr axfwubs +9tj .13j6lj*t:tq a 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 intenn7f w(dct )*inyqf3 9bsity is needed at the 1.0-km-radius Fermilab synchrotron fori*9c nbfwy3)ftn7 ( qd 1.0-TeV protons? B =    T

  How much energy is released in the d, u7+ rbdycbx.ecay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is ejru m .zl7d/,j3p;x ireleased when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antiny-c. l.y)bior0 2mc fleutron pair?    MeV

  Estimate the range of the strong for hhfp;v, app n/ zm:68l.hwj4 *k:hwxzce if the mediating particle were the kaon instead ,8xp. hp:phzzh;jl wm4h vw6:/ank* fof the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other +5e1s+kap3k)u x9h8nvlgsp fwith equal speeds. What minimum kinetic energy mufavsx 31l ep5k9)+gpk sh8n+ ust 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 a ;n i2apj1tm5vre traveling at the sam5jin pvmt1;a2 e speed toward each other, collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the 6 fk3eju84mqcm(jw s bp1,)nynej6 .d weak force using Eq. 32-3, given the masses of the W and Z particle.18 j m)nn 4jf6uqe6 kyebmpcjw(3, sds 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 antiprot p,fr k)5on vxju+cz9z2s ab.+on atx,+a)sf z2obnuvk5j.crp +9 z 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 impossible for aj t3a 1)io +6 ;tay5pb4ikctakn isolated electron to radiaoabitcta;)1ik ta 64j5k3 +y pte 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 electroo 86alg5k*f-(o mv3 dut(j wion and a positron, each with 420 keV o8mo(-dog6ot i a3vfu j5w(kl*f 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 possc1t/zh)wm wu8lr ;8mr ible? For those forbidden, explain what ctmz r1 w;8h/8) rmwlulaws 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 energy of each of the two products in the decayk1uyc40 xj5 e, ity8zd $\Xi^- \to \Lambda^0 + \pi^-$. 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 ki rfce0i08oz 5cnetic energy 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 z2f km2-v(xdclifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of th 6)znk(*of a6 jqp0*0lbstwb ie $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width ofv+b//*i l-cvkgxq m)d the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) o/z;4 ahje+n j8 fbpcx2f
(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 ye )e2*t1x:htsy c;z; xzes2nforbidden, explain which lxy; sen1e2* ;zzsxht2):e tycaws 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 antineutromc uf 323f. dr0sio0hsn, (c) a 3.32usdcm 0f fosr0ih $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations producevl36mxzc 8 y:h4w9i egkma :i+: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination needcziu *b5t6-b2qyn x y5ed 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 ujcu7* vz l/k/)p z6yn)kuqm; psing quarks (as in Fig. Below) for the reactionp q 7;lmknk )cup)vuz6/z*/ jy $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagran;,4 sjdvvar.t,x6- pysd 7s mm for the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energ.7p (dbfk; e-evdl m7ay of a proton whose kinetic energy is 25 GeV? What is its wavelen efk7 -7p(m.ed labd;vgth?
$\approx$    $ \ \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+t xia( h78jng6jk4uz(6e ut n with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do thht 76ji+tg( 4j6a( zuekxu8n ney 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 positronl18yu yo d5,t,uvlz5y annihilate each othoz,y,1tdv8 yl 55y luuer? $E_{\text{total}}$=    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 arewf8*x r p8yip np/-(xe possible, and by what interaction could they occur? For those forbidden, explain why. if(88p*ew x-pxr /ny p
(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 rsm.:hfx w7i3a eactions are possible, and by what interaction could they occur? For.w7 3afxm: sih 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 vpgxmwjd5s(fn4t70 4+zs e9s $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in thli,l l 6y jx)i,l9ez*10 ndspoe 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 of the reactions, Eq. 32-4, for pro,ys)rlf u12 k z./emlxducing a pion..lzsk yu)lxm21fe,/ r $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reacl2 m; yqo6ua1efgi;,bhdi3p0tion $\pi^- + p \to \Lambda^0 + K^0$ 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 8 9 n81slafvvgthere in a water molecule?    fermions

  A proton and an antiproton annihilate each other at rest and pwabx *g3se2 o:roduce two pions, 3aw*g2sbxeo: $\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-ca 1)fd3d-frv1uu ujy ,slled 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 32g s,hredc+7p u64b:wq -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 energyqpu4 +,ecwghsbd :r76 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 ta;*4llavhj,6 ,g2 un4gk/aafvt cn 4uhe following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to descw85;6 k: sifjfyekw3fdb2 q0aribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed o7+ 7e r5gv-5 3srj +yq/jlfcash+sutuf light $c$ is the speed of a 7.0-TeV proton?