Give a reaction between hewwuvel4v 6./)hp 4gtwo nucleons, similar to Eq. 32-4, that could produce a /uv g44vwe h.p)wehl6$\pi^0$.

  If a proton is moving zovfrw-x,8qydx7*jpe11 l+tbm; q,v at very high speed, so that its kinetic energy is much greater than its fo dlxvy*8-m,rvxqqb+11w ,jpt 7;e zrest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," maz4vp 0ismxh(hlkz2 8 1de up of the antiparticles to the constituents of nor h40 mpl(8k1 i2svhzzxmal 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 on78b71s xjc)e)zr5pig 0tgfsignals the electromagnetic interaction?

Does the presence of a neutrino among the decay products of a particle necessapvs.,s-g 1zsarily mean that the decay occurs via the weak interaction? Do all decays via the weak-.zs1vs,p a gs interaction produce a neutrino? Explain.

Why is it that a neutr)+.c 1 4f-54jgoywycz gopgphon decays via the weak interaction even though the neutron and ogpo 1)gycy+4c g4w-. zhj5pfone of its decay products (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, gravitationayxlhepug 9 5ath 2p:/(:d s1lxl) does an electron take part in? A neutrinodul 2xeg1p9:5h ph ls:/t( xay? A proton?

Check that charge and baryon number are conserved in each of th:a+y,qsd6 vf 9tyq9, yss+ycve decays in Table 32-2.:y s9ts 6v9sc,q,+ aq +yyydvf

Which of the particle decays in T:kmiwg/q5 z 9 +sf26o ke;hqnbable 32-2 occur via the electromagnetic interac2oek q5s;mf:+zb9q/hw gk6in tion?

Which of the particle decays in Table 32-2 occur by the w8*rn8m g: ao w0rgf:h ay2n.hreak interaction?

By what interaction, and why, d6sfwopp2 i*y 7da q17zoes $\Sigma^0$ 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 electromagne,6x anmtt ns;*tic interactiontm x6*n,;nat s?

Which of the particle decays in Table 32-4 oc5rf 6szab s4q8z.u eq7cur 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 of "neutrinolet" that was massless, h+dct*9,mwea j kl4a2 had no color charge or electrical charge, and did not feel the weak force. Could you say that this lm hca9 eajtk 4d2w+*,particle even exists?

  Is it possible for a particle to bgy +6gb zq7*/tes;gbye 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 chromos ie)cdtir4(bnfc;747b*nimm jmj 4*7b*p yodynamics, would it be possible to find particles made up of two quarks and no antiquatnji;bd7icm 4 oe(n7y7)i rm4 m4cj*fpb*b*s rks? What about two quarks and two antiquarks?

Why do neutrons decay when they ac 95w-h0ljcq rre free but not when they are inside the nucleuw5qcl9- c r0jhs?

  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 energ kt;vmhzw,97mg ::jz sy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV v50c8er dp :qld2wc c*electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used ish 7eqf9 wbl,/j(0q acn a cyclotron 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-u f+3iw cb:k4xzn7fk6energy proton in the 1.0-k+n6 3z7ickkxfwf :4ubm-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 Exapc3*j3)vmp *rnpuq;+)ae up :b1sqv yw38mgdmple 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 dwvilyt2olbm, w0j(m,9 , e)s+dggo6 jetails of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size +2l0v )9,,o, d6(yoi wj ewt sgmlbjgmof a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kzjwo rdv ctvg/ );+;w je/jc51 1a/qujV. How many revolutions do protons make to reach r)jww1j /e a5g+cd1o/; u/vjc;zq jtva kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengt69wnf u h b0mzvq,m r9uv5j2o*h ($\lambda$, 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 deutero11t.nd 6qn1* tayjk vsns ($^2\text{H}$, 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 used to house the magnets for tv a* 0pkj51odohe Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =o0v d kj1ao*5p    T

  The 1.0-km radius Fermilab Tevatron takes about 20 sec3 +5 vapx4dp) c8px c2nbdbek6onds to bring the energies of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done on3 8pk65pedcx+)2n v c4bpdax bce per 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 c) s3/s+ynj0 hck ,.fyhpa+ixa 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 Fermilya qh3894 ijeuab synchrotron for 1.0-TeV protons? j3 4ha u9e8yiqB =    T

  How much energy is released in the deq)2uwo k8,yrscay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy isqpr: vfts379 yat9*jj6r-mv p released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is requ0ku : tmsmpj2 )xc/**j*zgwobired to produce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating p:f qi4(sk *c6fkst,c farticle were the kaon instead osqf(4tf,ckif*c 6k :s f the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other w;g aga6 h);wbxith equal speeds. What minimum kinetic;ahggwb; x 6)a energy must each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic enu a7g6sp:m0.f(ddl kzergy must two neutrons each have if they are traveling at the same sp .:dkgl0usp7dfz m 6a(eed toward each other, collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of8no gwra 234ke the weak force using Eq. 32-3, given the masses of the W and Z pawro84na ek23g rticles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the t;i npdqu* j-4vwo photons produced when a proton and antiprotovn-jd;*4p uqin at 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 an iu8c q/9- iq h45o yr2nj1qcui3sjzys3solated electron to radiate only a single photon. (b) Withqou j58q19isz-4 ycjrsnc33 uqyh2/i this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of thq*k tze3 z 9xia)1tt0we two photons produced when an electron and a positron, each with 420 keV of kinetic exk3 qzi e9ta01z*twt )nergy, 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 ar duvvc 7);t x)lo-dwc.e possible? For those forbidden, explain what l ;dd ouvt)w-lc. xvc)7aws 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 :-kjbnned :x +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 maximuc35rlyu uq2fs0d n*u-b w+fr 3m kinetic 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+isg*oefc8.et u 3.yz5bz 2d j lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width ofrhmj )b-u(i u 4j-.mfd the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width or 9 v0o618novx: kh cm-mf*whsf the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncntngaa2s5 1d,4f,vnn jqe /z:ertainty) 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 thoyon vp1+h.e )-njit )xse that are forbidden, explain which laws are violat et+)h)ynxp.-n o1vijed.
(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 neuteu;t.g+,a bnhron, (b) an antineutron,ng e;.h+b, uta (c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark comq4)yt d;fe hs:binations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination nee, xpz:b* s7,kbsay8+t u wkzl*ded 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 qua4z,7n(b97jkdvqa b3z mf5:mgxzuw h1rks (as in Fig. Below) for the reaction79 7 xngvqazhjk 3z5(b4:wbm1 m z,dfu $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for g-xwa/ b5a6*;hpkzmzh 5rkt - the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kin6u gdk- 82b*hbf-oc ysetic energy is 25 GeV? What is its wavb82u6-kof-cs g *ydbhelength?
$\approx$    $ \ \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 ;zd2 2b 6sabxswith 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 reda;sbb6xs 2 z2ach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a pos8 d0,, xh t0nd9f-wv+cevk mcritron annihilate each oth09 ,+cd8wh kecxv-rtdv mfn0,er? $E_{\text{total}}$=    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 followin lpg) 2gejp80hg reactions are possible, and by what interaction could they occur? For those forbiddep)2g ehgljp80n, 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 what interaction could f1m7p hm8x c. ha:6x,x ggbfv6they occmb 8pfgx6.mc,axhvx6h:7 g1 fur? 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 ac7hbexscfem- r2 1paf5 mg qzc/53 n/( $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the ef; 1noxw4nq)z,o zz6nlectroweak 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 reactucy (lo d o)6q5,-m( ozk hapwtx;wq-8ions, Eq. 32-4, for producing a pion.podlqqo6h- c; 5,()oatx( w8-kwyuzm $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the rehj*pc uml9f15 o cl1d-action $\pi^- + p \to \Lambda^0 + K^0$ 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 fermiok/c 3fy9f5nauzkah f 1z z8g.-ns are there in a water molecule?    fermions

  A proton and an antiproton annihilate each other at rest andw75lb2lj6sf v produce two pions, 5 f7 2lsjvl6wb$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distance ofr z;b,rc7r/ we2xe wqn720rfp $10^{-31}\ \text{m}$ 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 timn6+ zcgn6sc:v2 pue :se, 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 th6n2u +c:6snpzecg :sve lab, on average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the foc1/aulwo/er zw( l/o.llowing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the reactiujkj.k f y. rnis(48t7on $p + n \to \pi^+ + \pi^-$.

What fraction of the speed ok bxmus.kwngl67 9j*: f light $c$ is the speed of a 7.0-TeV proton?