Give a reaction between two nucleons, similar to Eq. 32-4, that could produce h:lb2v(30 ge:dk bd mra eg:2md:3 vh( bdb0klr $\pi^0$.

  If a proton is moving at very high speed, so that its kinetic energy is mudoo 8;kfgjqm-(dz7gjz; xg75 ch greater than its rez7d7g q8o ;gzk5j(o; d xmj-gfst 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*ulb rm n6yf0u3ye)4 t the constituents of normal atoms, consist of? What might happen if antimatter, made of such *64t urn0fy3buel) y mantiatoms, came in contact with our normal world of matter?

What particle in a decay signalwq p)r*p8j r;gs the electromagnetic interaction?

Does the presence of a neutrino among the decay products5: pqdem0m d;p of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produc0 :medp5 pq;mde a neutrino? Explain.

Why is it that a neutron 1ru x2r/2 zhosdecays via the weak interaction even though the neutron and one of its decay products (proz xo2/h2 1surrton) are strongly interacting?

Which of the four interactions (strong, elect* ese q,:m h54/ioevuni: zc(bromagnetic, weak, gravitational) does an el4mz (:eo:b*ni 5hi,/evu s eqcectron take part in? A neutrino? A proton?

Check that charge and baryon number are conserved in each of the dei3e/c)h6wdcz d+x v0raa, ah.cays in Tablex0ah ec,r.6zc3di)hawv +/da 32-2.

Which of the particle decays in Table ghn dqoqbr9) x8ib,e (9b4cq; 32-2 occur via the electromagnetic interacc4bq8();e q9gdox bnqb9 h,irtion?

Which of the particle decays in Table8ji c msc*pu/1 32-2 occur by the weak interaction?

By what interaction, and kq wib-anhmd wswf-g0 ;i fz49)87:mhwhy, does $\Sigma^0$ 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 Tabl;g g,eo-*e vr:n*f 2qysjh:um e 32-4 occur via the electromagnetic interactie: efh,sumgg *;qr-*: o2 ynjvon?

Which of the particle decays in Table 32-4 occur by the 4 h/* ifwnb7tpweak 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 no/kv ;2k qs-n;p0rhd dj color charge or electrical charge, and did not feel the weak force. Could you dk s; q0jp hk2v/-;nrdsay that this particle even exists?

  Is it possible for a particle to be bothzr9o*7g sg5k ish(dj9
(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 chromodynm1j1o ;brn-bq amics, would it be possible to find particles made up of two quarks and no ant -r11 bobn;mjqiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when they are insidep t 8)gf2ji5ow the nucleu )p8 iw2goftj5s?

  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 kinetis) +vdrb79rr wc energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV ;0owb35svxh/ y(p amwelectrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protons makej: hayz; :d/v cybnm9um4j: /v $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revn6e 2op4o;uc79e dgf. 3efzs uolution for a very high-energy proton in the 1.0-km-radi du9.fo4c3e on uspzeg;2 76feus 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 o)(fbwj./hsk l-j qw4hzzm6: gf 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 picking out details of :s f p-xolp8v1vnn 3k/aa0k wr,k/z6t the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size ofk6 xwna:slr1v/na /pptk0,k 3 zv 8fo- 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 lm u )0h+r*yyvdo protons make to reach a kr0)+yv*l huym inetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengt9dbd:wf5xy7of gfe3 9h ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radiuse;(7:p c vk+gznda z:q 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 tunnel that will be usez el8d tk3) v1ul-o)cgd to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7te831-vz)k l g)lu cdo.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takfuv ztb c29 7v5,us* :nsux1mbes about 20 seconds to bring the energies oub svbz n tuvx5,u7fs1:9 mc2*f the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once 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;j)8 dsrd(did j;kb1e 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 a55xxl c6luj e7t the 1.0-km-radius Fermilab synchrotron for 1.0-TeV protons? B = 55u 7c elx6xlj   T

  How much energy is released in the decae2hbq h, 4fr2wy $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released wheja835nmfh* fuetjij io9 p,*)5o )zmfn a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produyad2,dqa; (tcg*rh 4x ce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particju/wglt 4gdrdu2; 9q; le were the kaon insudl9 ;dwr/jtqgg42; utead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are headinxv3bgg.r c a8;g toward each other with equal speeds. What minimum kinetic ener ag ;.8bgcxr3vgy 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 have if they are tra xjoll07h(zg* knu; igf2n7r)veling at the same speed toward each other, collide, rx *0 (ggjliokzlu 2)h7fn;7nand produce 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 t qi;h 3s7lz2sthe masses of the W and Z particles t z2is7lsq3h ;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 pro29kdfow)r j3 zduced when a proton and antiproton at rest w)drkzf923o jannihilate? $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, that35v*ptp cfb f x6q(2kb it is impossible for an isolated electron to radiate only a single photon. (b) With this result in mind, how can you defend the pho* 6p2fb v5b3(kxptfcqton exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produced when an electron and)ly984rrl bl wx iatxej)s ,9z:ob/7w a positron, each with 420 keV of kinralw9ste)l:4l,x b/8woib79 y) rj zxetic 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;lrqy wn(4r s1,zg,su and decays are possible? For those forbidden, explain what lawslr;,4y(1qsun wgz ,r s 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 tkinol6 8j 1a,d+i3ot awo 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 energy of the electy9 g gzp9ntti+:8v 7ym jc4t3mron 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 estimatpmkfai579s *l e the 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 t3c.6z6i tlzyqe-nb .a he $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of th3c dzlxc 803 saecfbx/)u*d-de $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertaintk 4ok g p/cfa**ncgk3i j-uc.1y) 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 * f9 1bg6u/tviuzthh :decays are possible? For those that are forbidden, explain which la uuh1 hf/z*ib t69:vtgws 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 5i0 r s 06pmu/avxguu(can form (a) a neutron, (b) an antineutron, (c) avagr0 xus05im 6u (up/ $\pi^+$, (d) a $K^-$?

What particles do the foll ;1k;p3d3sr;*lfskkphxitkq3yu 53 lowing quark combinations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combinfq8w54;ziut)ok zont c ,uuv3wn15m 2u 07dm sation 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 Feynx6 zl5jn7gp 1oman diagram using quarks (as in Fig. Below) for the reactionzp75lg1x 6noj $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram f*h2 (syvm4lcl or the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whoseot8 u)t4y;jkb kinetic energy is 25 GeV? What is its waveujy4kbt8t);o length?
$\approx$    $ \ \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 t9 m/rb qeebt59he 1.0-km-radius Fermilab Tevatron with an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel anbt emq9b5/r9 ed 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 annihil zopubl8m2,m e4.i0weate each othe.e,b20 z8 opi mulme4wr? $E_{\text{total}}$=    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 )s2 nbk :g7oc9w :fe)6 kqhzamby what interaction could they occur? For those forbidden, explain w9)gnfa :h7sqm2 c z):o 6bekkwhy.
(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 a(1arprg-k n l)+qd/ *g+xkeh 8p sy3pure possible, and by what interaction could they occur? For those forbidden, explain why.s)r3l(qp*hukek a+p np-ry 8g1/ dx+g
(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 ,mac q3d(k 51vqfp 1sz$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak theou;qw8v 4h6dj mry 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 fbtbgdop4,6g 7/+ja, p t,bq whor each of the reactions, Eq. 32-4, for producing a pion. hqbt/ 4,gj7 g,w,ppa+ob t bd6$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the readhq:m 1h vw17j4lgu/gz d 9h-rction $\pi^- + p \to \Lambda^0 + K^0$ 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 water molecul+x,/xs tg2(lyz r /qxck+(geie?    fermions

  A proton and an antiproton annihilate each other at rest a ip h4c:kzxu93nd produce two pions, xi:p4uzc kh39 $\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-call,*m /vii) z ybds.+/)x ss er1yamaq6aed 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 igxan7d9zplczta h 0-+890w brn terms of proper time, measured in a reference frame0a w7anrxb- 80d zhl9+9gctpz 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 average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing :hslx1m i g*nq)*xxd1 particle in the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the 8dcsg a(9zw8p(sx*mw reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the spee7fq:h o ( gll:bw/9luud of light $c$ is the speed of a 7.0-TeV proton?