Give a reaction between two nucleons, similar to Eq. 32-4, that could p0 ctc iv zj))om/ jut4h9mt4,t rki/f4roduce a thk4 mj/tjo4i4rvm9 zt0)c ,i)u/fct $\pi^0$.

  If a proton is moving at wdwixp:p2 3,e+je kv :very high speed, so that its kinetic energy is much greater than its rest e:3i w, x :j+epvpd2wkenergy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticles to the cdt7q4 s 8(etwzonstituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with our normal worldt(ts z78wed4 q of matter?

What particle in a decay signals the electromagnetic interac 2 hrda5pf4.vc k6y/nbtion?

Does the presence of a neutrino ag *; uu9lt;:ibqiaxbex f3:( ymong the decay products of a particle necessarily mean that the decay occurs via the weak interactionqxl;tx: f3a9;ig uub*:bi ey(? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction rc 7c9(1jvi,m;on8zo: rwxwkuf n/5reven though the neutron and one of its decay products (proton) are sj/5(rn uw:; cw7 rmn91vo, k8fz icroxtrongly interacting?

Which of the four interactions (strong, electromagnetic, wea,5dksosa- )k- jpc-.yqs cu wh6pu.*h k, gravitational) does an elec.*) op duuw.k, --kchsc 6-sqjaps5y htron take part in? A neutrino? A proton?

Check that charge and baryon))/*yt-k*rn y :7iqgbrit cog number are conserved in each of the decays in Table 3/gr -ttrcgby i:iq7*)ynko) * 2-2.

Which of the particle d9x3eridcpgr. y )y/s,zo 2xd9t*g:p zecays in Table 32-2 occur via the electromagnetic interactionp edgrxy)9 3,sd zxtgir. z*9/2ocy:p?

Which of the particle decays in Table 32-2 occur by the weak interactio(jzbip,g); 16fhi4gngd0 w( u ewy z7nn?

By what interaction, and why, doeb cp/+bfp0 y1zs $\Sigma^0$ 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 i;39zau3 *bfdvhs (f r *jikpx-n Table 32-4 occur via the electromagnetic interackfxr(9*d3vu sp *fj;z ha- i3btion?

Which of the particle decays in Table 32-4 occur by the weak a g57b w1ux e6vvawj*+jdi h2+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 massless, had sc q6an m) nemf:/2:vnno color charge or electrical charge, and canq)snmm 2:/en: v 6fdid not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to be both z r9*0pctw2yy.1(zwgcsl np:
(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 chromodynk-glnnybg 8a /6 g1b3yamics, would it be possible to find particles made up of two quarks and n1bg3nk- 8na6y lb ggy/o antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when they are insi4v9tn eku5 aq;de the nucleusnq5e9 a;tuk4 v?

  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 prot+ne;odi m0f)z on whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons. E 7ov5 8 mijik6gt0je g*=    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protons make tkb2.nv a kw,3 iys idm2uu69p(eeq,. $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very high-eneyd x8fyc)-b2bp* vda1 rgy proton in the 1.0-km-radius Fe18f v-b pbx*ay) 2ycddrmilab 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 Excd p6-zrq-7 vjample 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 pickiecs8vmafe 1va(,o*, e ng out details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleone ,e(*ca v1efomas8,v in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kV. How many revofp y5f tuzn9o,lz/7mc7f1g :xlutions do protons make to reach a kinetic energy of 257f9xylm cz5 o17, f/gput znf: MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (7m fvwko4al+ m5+;.l izz/ jwe$\lambda$, 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 deuterons (o8v o q76qf(x6 ,xck .atj5ecs$^2\text{H}$, 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 usedi*ksl hrm4p9s4x n5 dl4gg0r 5 to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetixnsh0k4l5p54r m*d 4 grlgs9 ic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takmo6c(,x2i dv1zj qrm- es 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. Estimarm,z1j qi-6dmv(oxc 2te 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 of a particle (chh2aw6tcx oa5i2/)qi m arge $e$) 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 Fermngq,9/fr5v doc6z avv5iv+il f-og ;3ilab synchrotron for 1.0-TeV prot o +6v;qn-c 5zl,gvi5g/ior9d3fafv v ons? B =    T

  How much energy is r,i3j5hj 3cd ) g.ovrxveleased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy n4dt,s nrgi67is released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to lil)r0xb ic3o+ 9bg/mhos( y*produce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particle were the;r-np*na- 2hs p*jr eu kaon insn -r2ea;hs*-*unrjpp tead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading tow t2ly r+zls djse:a1rr 5/*f:nard each other with equal speeds. What minimum kinetic energydrj5ers *ra s:l12 :flyz t/+n 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 two neutrons each havxu 0,9) awov 01:datyi gznz2be if they are traveling at the same speed toward each other, collide, and pro0g2z9 0i:bvoy, w)zxau dt1na duce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak forcee4w(hy +q.m x 3bltfr* using Eq. 32-3, given the masses of the W and Z particles as abowqr h(*elf 3tb m.+4yxut 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photn,ix(ix+y4 fgons produced when a proton and antiproton at rest annihil ,giyi( +nxxf4ate? $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, thatqbc/1b2ettc( r. 8 wps0usb 4d it is impossible for an isolated electron to radiate only a s b8b 4qs/dbew.(cru 2tcpst 10ingle 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 elect4 b.t:6vl. bp0jrywhl t ;n9hpron and a positron, each with 420bv lr hl0hj6t..9:4wt;pbpny 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 rey ukhoqmmebr);w6 233 actions and decays are possible? For those forbidden, explain what laws areoy m6b3;)3mwk2rh u qe 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 prod/92h by jmkfo6v6u2bqucts 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 2) (i ysz,sk 32;rwb:nncoek tof 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 eneii0 b29rf4+zot.ovcw rgy 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 theer+gc .9pfgy, $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width ofzf dby3. ap7kv16no/ip; ;cfd the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertaini3fxw (guc8/j mh(s. oty) 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 tj,2 vaozx4n4eh )e y.yhat are forbidden, explain which laws are vi ya2n v,.x 4oh)eej4zyolated.
(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,3m ewux2+dchmgl105d7kx g-h wgar : (a) a neutron, (b) an antineutron, (c) mlrwe7g1,gwx-h3 0 xkdh5 +du:agm c2a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations produce: (zieu1jb++8 x / z(roaxa+bi /ja) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination needed to+ g +vcw:sf jv5jcpu7j (nvl*: 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 (as in Fig. Baqpl oyr7fdk: x :8o*4elow) for the reactionlf 47*o ko::8xyqprda $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the 8ua),nrqn8q f reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? What:9m)eu+cqr tj tw) 5mj:,nzha is its qzu) )mjan,rje cw5:t9m:th +wavelength?
$\approx$    $ \ \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 ,rk2+ /ks9)xhxukmrdo)0uatwith an energy of 150 GeV. If they au) d/axsh)k ,m+k2r9kux0o r tre accelerated by 2.5 MV each 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 eleooi4i /hjn+(a0rnfp+, fw p4wctron and a positron annihilate each other?nfj4 /p+,r(oiohwp4i 0faw n+ $E_{\text{total}}$=    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 reactioey hhc 0) 81 x0ov7jdawoh+jg,.om) xnns are possible, and by what interaction could they occur? For those ax0xgwon)0eh voy+j md1,jh)o8h. c7forbidden, 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 whgf55pq/ bs 9j*)ncfxs at interaction could they occur? For those fo9p q /sg*cbf5)n fsjx5rbidden, 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 h2g,coc9/ fyrf)-fql+ef d. u $\pi^+$ 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 at abo:hm0pextww3 +ut $10^{-18}\ \text{m}$. 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 producing.k1w0 wq exqu5,uzm-k a pion.0kq-,w .u wum zqe5x1k $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reacti,0r)mg(m;ra i dob 9yfon $\pi^- + p \to \Lambda^0 + K^0$ 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 ferm6 x ,rfonuw.)5e,rpd iions are there in a water molecule?    fermions

  A proton and an antiproton annihilate each other*mr f,e* xu5de at rest and produce two pions, *xdf5 u*m,ree$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distance ipptsc s 3q986of $10^{-31}\ \text{m}$ 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 propanwu(dk* l xyl9ve:h+ qb7-7r er 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 track be as measured in t9bh *7w +qvua 7e(dxn:k-rl ylhe lab, on average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the k rkgkc426fq)e)w.f grzo ;kw*x8ey:following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe th- yi1 6:tr..-jjb2 ghboluxooe reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the stprg9o vxozb+ 4qx2kn6::0g a peed of light $c$ is the speed of a 7.0-TeV proton?