Give a reaction between two nucleons, similar tas5hqca ,p8u:0t6qhu3bhh/b o Eq. 32-4, that could produce a a0hu:hc6b/5 t hbsqhq8,up3 a$\pi^0$.

  If a proton is moving at very high speed, so that its f:m:whpw 0cch (gqlf9a:dzg2b ) 7*x lkinetic energy is much greater than its rest energyhzm:lwg9 dg paxbflf w7)cq*02:ch :( ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of thaz+dhaqi /t9fg/a y3)e antiparticles to the constituents of nor zh9iaf/a+gad/tq) 3ymal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic interac+a:o0w02 zgvy8fj nqq tion?

Does the presence ofsbju*/ h* ujz,6(nkeb a neutrino among the decay products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a ne/hz (sun*e,*jjbkb6 uutrino? Explain.

Why is it that a neutron decays viaa wi, r z,cyv)p7 euj6r.26lwa the weak interaction even though the neutron and one of its decay products (proton) ar lw,2crzai )wp yje6u76.,rva e strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, gravitational) wr( d7c 6q;8/od5kgv5y +zuj r q6exksdoes an electron take part in? A neutrqz58eqkjsc wx;dr5ro7 d6y k( v6g/+u ino? A proton?

Check that charge and baryon number are conserved in each of the decays in T:56x9 9h,l jeub trfzzable j 5rztb9lhxu9 6fe:z,32-2.

Which of the particle decays in Table 32-2 o*co96cs 86n 36 ryqtqcl1msg gccur via the electromagnetic interactin16c g63go q9sl*mcry6 c8tqson?

Which of the particle d8 3r3gyu*d ,fzba;d4iiuh-ka ecays in Table 32-2 occur by the weak interaction?

By what interaction, and why, does v5 )6dxbjc- obq/,tk y$\Sigma^0$ 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 ov9u+y 1w6fh +5gbcy srccur via the electromagnetic interactr sf g+uw+cb h1vy69y5ion?

Which of the particle decays in Table 32-4 occur by the weak inter ibn61dke -;78nuhu+mxv hy0r action?

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 ofu,s7jrv*rx+ e ; a 95aonrc0gbwu) 1eb "neutrinolet" that was massless, had no color charge or electrical charge, and did not feel the weak force. Could you say that this particle even exists?7*,1 ve c;or5 a+ub 9) xbsanrr0juewg

  Is it possible for a particle/kpju+qvt2mo;p6:r iv 7 0ywg 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 chromodynafkobu +8-q.m amics, would it be possible to find particles made up of two quarks and no antiquarks? What about two quarks and abmuko 8-+f.qtwo antiquarks?

Why do neutrons decay when they are free buthulc( .ge whk;4,/tkh not when they are inside the nucleus?l(whgk/cuh., 4 ;e hkt

  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 k6npj nyd,kcb. e *j2 /:vpzg;winetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons. E =t+,joc gy9 3jp    $\times 10^{-17}\ \text{m}$

  What strength of magn )mijv5n)q w 3yee7d3detic field is used in a cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete re ub3z6 6f2mloirua( 3jvolution for a very high-energy proton in the 1.0-km-radius Fermilab acceli2u(abj 6 zr6 l3muo3ferator? 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 os/rhrte ..2e mf Example 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 pickl /m0bz,m ;olszf8+u cing out details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with themc ozfzl+/m 0bs ;,ul8 size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron1r xl7 qi.c9pn;6kewh is 55 kV. How many revolutions do protons makerhcp 1i69 lek.wqn; 7x to reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengtmia h omumd7 /0m*-;rv 67xnpbh ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radiu2d1t2g6d/z c 7ticdwxs of 1.0 m is to accelerate 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 tuparf 3 q6p/eogn kc1.+nnel that will be used to house the magnets for the Large Hadron Collqrk cp 1fg p.eo/a+63nider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermi6ukdnz7 ;f3 a/qai 7balab Tevatron 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 3dkan6 a ;uqi/7azbf7 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 o9ljcea7hz.q /f 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 intensity is needed at the 1.0-km-radius Fermilab synchroc r- s z:bwdesp76-s4ctron sr: z7 4s-cspw 6dc-befor 1.0-TeV protons? B =    T

  How much energy is released in tojto0 90 ;petthe decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released wn89 +wqf.d ijq3wiuo7hen a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is requiwj bo(:6q z ajjz+ v 0ayo1tscx;xha ;)+m:b.ored to produce a neutron-antineutron pair?    MeV

  Estimate the range of txqj rj a y .y1cath53c; eu7b.n, sm0fg-ik3h5he strong force if the mediating particle were the kaon instead of the pionni bah,yj35m5g khc0te ;x af-quc r.3y1 sj.7. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. What minimum kineteilbhvig:+f y +5i(d/ic energy must eaie/ify v5+(ghl bid+: ch 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 tr),e fm0b-rm, ten g.swaveling at the mm. ,gtw)nbef r- e0s,same 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 weak force usinbaaj)i hoj 509g Eq. 32-3, given the masses of the W and Z p)oj5a9 ahj0ibarticles 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 zxcsn4 +j 3(d p/efz0ba proton and antiproton atz pj4s c+fzdb(3n 0x/e 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 anl ,h/ g47bioxs isolated electron to radiate only a single phxo/sl74h g, iboton. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wal81mjusn*e f+velengths of the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihilate head o 1*jsn+m f8elun? $\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 reac,) 6dc2rrzfzc tions and decays are possible? For those forbidden, explain what lac) fdcr2,r6zzws 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 ./he/zvtq1 gk/sh y2wtwo 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 azzpfe w) )1f+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 lifetime of t2go,d-kn+cidlwlv4851ni u dksd 8u :he $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of4zthu87b jle5gz v n*5 the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width onnx5u 0 xzq)w-1h. sarv82sv uf the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (oi51e ivd,5h/im gtauk zz42g7r uncertainty) 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 pwt b)9 onuov6)z sx;ludw eyq)5e5;- eossible? For those that are forbidden, explain which laws are u)wevyoo ;z6; 5 xqetulb )es9)dn5w- 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 (23nefcey3x:v5z5e bq a) a neutron, (b) an antineutron, (cc 5e3ve bx2qyf35z :ne) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinai8ayj . ju 41 :z77sxjlnb1ntptions produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combin).t4oly bq) dnotq)s9ation needed 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 qua-,uycsn4* wn grks (as in Fig. Below) for the reaction ,* nuwgn- ycs4$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the re bv5d4nx4:bundl+ 0z ub.d4kmaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? Who6sm0l ffaq o/plxe6 60tzt 9.at is its waveleng.zfof060/9 6l most6p t laxqeth?
$\approx$    $ \ \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 Tejd:d ,kq8,ruuvatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and approximately how long does it take for them to reachj,u r:qku,8dd 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a positronr(i*g4 p;m0q5-pn( fxfzvd;sd )i olg annihilate each otheri*di-df n(fr5gszl; p x mg)qv0o;4(p? $E_{\text{total}}$=    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 h2q1i1rwn5reqn 0 o c+possible, and by what interaction could they occur? For those forbidden, explain whnrw ce nqro1h0+25 1iqy.
(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 what interactionq8rxo he(7 /ujpdp6u . could they occur? For u7pdx/.qpe6ouh8 r ( jthose 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 v2xz wq)t.4l h$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electrop,esjv+zf j v4sc )4w2weak 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 reactiondt*i ;l ea( k-30c*purqy2tpls, Eq. 32-4, for producing a pion. (*r yi k*;tuc0al-d p2eqp tl3$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reaction kirs8i2g6a1uj iv./ucmb dn 04)z8qx$\pi^- + p \to \Lambda^0 + K^0$ 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 th*/;.; j sg0jpfoe )mo bamw9hvere in a water molecule?    fermions

  A proton and an antiproton annihilate each othe:g2- ek j69ucbyx /btrr at rest and produce two pions, / yjg e2rt-cbb 9k:6xu$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-ca6+ y 8ubadbz6 y(iti91pbux5vlled 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 32-2 are in terms of proper time, measured ip,go*3x7 zeat ,oolx/g-4c emn 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 the lab, on a 3mgoel-xc/o7a,4o *,xez tpg verage, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in t9eld z ,qdb--.le;s1u(tgs q rhe following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to descri7oj) msv 4;.mv ag g6mjp/wg1mbe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed jlr 6ig1p h6fk+qx (634s*r i9 52udzpv wbogrof light $c$ is the speed of a 7.0-TeV proton?