Give a reaction between two nucleons, similar to Eq. 32-4, thathg:uiqn76d+ayh8 aa) could produce a d8h+ag :hqa7n yu ia)6$\pi^0$.

  If a proton is moving at very high speydq2n/kk +3j9jmwi o 1 -e3qd a1jdjt7x9i5fy ed, so that its kinetic energy is much greater than its riymj 3yke1d9 k1xatoqn23d9/-jjw jd+75fi qest 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 constituents2 yp ,skn;fqf)h8no b);jlxi9 of normal atoms, consist of? What might happen if an)p8,;f2yn xfhj qn)9s ;lkbiotimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay 1m/x:5a5uvywgoi az 67qbt/ ae:qmywczh6 2( signals the electromagnetic interaction?

Does the presence of a neutrino among 7gqw4f -+l bhm+j:lhlthe decay products of a particle necessarily mean that the decay occurs via the weak inh4:fm w+gll7l+-q jbh teraction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron def4 r8mznc;ekr3c ll:21q,twxcays via the weak interaction even though the neutron and one of its decrx3c:efnlkm2,l8w;rq z 4tc1ay products (proton) are strongly interacting?

Which of the four interactiojzhpw d.kz810l.l d)hns (strong, electromagnetic, weak, gravitational) does an electron take part in? A nelzjw dhl.pd.)1h z 0k8utrino? A proton?

Check that charge and bary, tgic8jvvb53on number are conserved in each of the decays in Table 32- tvjbc58vi ,g32.

Which of the particle decays in Ta qav)86mtzd:n ble 32-2 occur via the electromagnetic interactio8dq:nmz) 6va tn?

Which of the particle decays in Table 32-7 uwzg1/ mw -wx/vzu8-c kfue02 occur by the weak interaction?

By what interaction, and why, doesbkuh5td3q .g* $\Sigma^0$ 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 deca b n8nh2(r+yxrfo(*ad ys in Table 32-4 occur via the electromagnetic interactiony n8xrf h*(2(r+dboa n?

Which of the particle decays in Table 32-4 occur by the weak ywvu+ *xr7v4jinteraction?

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 3km* hv ysfi l( g0t2;my5 i6-cfzc,lmno color charge or elef6lv gcy(2-m *mm0h3i ,zsi cyf5k; tlctrical charge, and did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to be botfzlf* f hhz:p)t 7vijg gf9 u610gt(1jh
(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 chromodynami+nk:pp1 jjum8y6x z0s cs, would it be possible to find particles made up of two quarks and no antiquarks? What about two quarmuj 1sj +py8x6nk0pz:ks and two antiquarks?

Why do neutrons decay when they are free buqwo7 +vjqxcwh9kgv( gp2 7(+y t not when they are inside the nucleusoh7+ q vk2w xp+g7y(qw9g (vjc?

  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 kila ppnhx byt-z 2cca3, (4x71ynetic energy is 6.35 GeV?    GeV

  Calculate the wavelen2ytm9rg20 se nen fy7pf2/,u:i xzg/t.n (zzngth of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotlc cm5w8d,xd6wa;:wxys i l; )ron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very high-energy proton ingnl -7mu6. snf)akr b/ the 1.0-kng.lknmb f s7-/6u ar)m-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 Example 32-2zi8zx:+og-w+,7nt*v nbjm+ :mza )3ubgzgch 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 detaildrr8lcg/j cg 6 py57z1s of the nucleus: 30-MeV alpha particles or 30-MeVcdrj7zl 8 y1r5pg6/g c protons? 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 many revolutions do zogzujc/29w;u;nox5l xl9w7 protons make to reach a kinetic energwxjo7; 2 9l/ uzx5ncw lzo;9guy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength 2xpm.1g- mx y8fzv; jr($\lambda$, 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)+ vnu3iplby3 ($^2\text{H}$, 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 thax 383 f*s6kv,jzg(ps h4wzzdb t will be used to house the magnets for the Large Hadron Collidhg,s zk fz*vzp(b348 swjx6 3der (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds to bring the ene; 4 g6jja 08d9s9)nciqt( b,btlxyc hergies of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once per yq)s ;hexjb a69,ctln4 j(8ig0bt9 cd turn. Estimate 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 partiuvpxl3z1 x- 5zf ,/mxbcle (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 intep/hw:gy kos8 kcpq*,-nsity is needed at the 1.0-km-radius Fermilab synchrotron for 1.0-TeV proto *:ykp hsp, ck-g8q/owns? B =    T

  How much energy is released in the de tpe ).oae(m+vcay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released wfxoho *) tvjv (o+5t mr((j;kphen a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron4) d )bfqxjgtne-zj*da+nadf7w5 1*z -antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particlznas 76mfxsnl2 vw(+. ; p6hyge were the kaon instead o+(xsas6mg wpnh. lv2;ny 67z ff the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. What minimum kinsse5t7gc f6m nj.ihmm s-p-/*etic energy must esnsfp.gj 7t m5mm hs6c-*e/-i ach have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must two neutronsn.lko6qaon 1.jvjc9dy4x x 16 each have if they are traveling at the same speed toward each other, collide, and prodjnc1 1dl vjxo6yk.oa.n49x6 quce 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 tho k/x6miv e/mp0ivh)6e masses of the W and Z particles as about 80 to /xivio/v)m0 me 6ph k6$90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two h-y4:t an(i frphotons produced when a proton and antiproton at rest annihnih(4 fa-r: ytilate? $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 encd 7ymp2we( 3gy 3x2jlergy, that it is impossible for an isolated electron to radiate only a single photon. (b) With this result in mind, how can yolyc32 3my 72edjg w(pxu defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelen* /1 .z3g)f*2f:o x7bhxm yica ck+e eopbr8bdgths of the two photons produced when an electron and a positron, each with 420 keV:xcgomi/7ax+f3.c)ebby fezpr8h1 2bd* k *o 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 pouup2 -7o+g/;sx 1:mfw hejdxjssible? For those forbidden, explain what laws ; /h1mx+jofudu xjs 2-w:p7egare 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 w)t10lqc c*2s,h rlio 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 tv 6q1c/je) 3 mbaj1cz fgh8-denergy 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 th04 xq/zqiuq,a g(f le-e energy 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 tono*f7.ulkzree .pcd7*5za kq cbfx468 (g g3he $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of tyq of,(*zcxt g3s2e/ihe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty)d20 snq)jg 4st 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 dh*o . vzm-n,/le flv*,o -aobvecays are possible? For those that are forbidden, explain which laws are violatedo*l-*e zb .hoo,m vfn ,-lvv/a.
(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,k u*hwc1f+ ;ar (b) an antineutron, ( afh;k+ *1rwcuc) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations producf6evda5zp a2(e: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination j7)5cecc aqw9 t5(zegneeded 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 (as in Fighznb6u b7/p- g. Below) for the reaction pb-gzun7/6h b $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagr itst:sj3 nukfp,u4z -jd 6km6x015 mzam for the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 Gen (-se+c* uvymtp;.ts V? What is its vst-p.tc*me s;nyu +( 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 ic/lf. q lqidp: 24y,qinto the 1.0-km-radius Fermilab Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far dl i, 4:.qc2pliy/fq qdo 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 annihiboxkt6*+yb9 d vh4 1hilate each otherb9bkti6+o *xvhyd 14h? $E_{\text{total}}$=    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, and by what int.8wdtx(nj m3cig1(jk (bjrg8 eraction could they occur? For those forbidden, expm(bd.j(ji (jkcw g3gx8n 18rtlain 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 by6ur a.v9-h xrs,d)v ukm c07db what interaction could they om6)v c v-ubh9d,xark0du 7rs .ccur? 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/ ry7q /nrg7sj k088xxyn1mom $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in tjds8(v8)n b qghe 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 foj d17grv 5jv;tpv3 ic.r each of the reactions, Eq. 32-4, for producing a pion. gc vjp;r5.v1i3j vtd 7 $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value 3opizy*lf-dvhf8 d9) for the 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 w/ )ykd;fq;s wnater molecule?    fermions

  A proton and an antiproton annihilate each ok6 wpaixats;6+5 .exother at rest and produce two pions, kiaps6x;ae . 6x5w+ ot$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification dista mkdev5vt.r246ice6av 4e/ 0hjq2uxg nce 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 propghv , uo ds54,anlv2m,er time, measured in a reference frame where the particle is at rest. If a tau leptonv l,m,ah24sdu 5vg,on 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 particle in thefgy8s.nnodp; u3 ag z c*,:1hu following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to desp ri.w+-ez mk;pihpi0*g 4nh(cribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speedwji gvsumz ah;ey/v3) 9 8b4*t of light $c$ is the speed of a 7.0-TeV proton?