Give a reaction between two nucleons, simila w3; fvvgr knetx86 opjqy*,/,r to Eq. 32-4, that could produce a 3vx*8r po /,;gwj,kfyq tvne6$\pi^0$.

  If a proton is moving at very high speed, so that its kineti bzo3m.iq(nk-bz0zptq :8dg1 c energy is much greater than itiqd 8k t1mzp.zq3g:bnz0o - (bs rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom,"6a suzg2o6fgx ,1j zwg,3xg, m made up of the antiparticles to the constituents of normal atoms, co 1,g xg,fwszm,g2j6 gx36oa uznsist 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 r-z6;n w8lymwmfq.(finteraction?

Does the presence of a neutrino among the decay 3n (j)ven8sd m d 2vv; vlb1ea1l8o;cgproducts of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explen)(3 ec2v1; 1mag s8ollnb j8d;vvvdain.

Why is it that a neutron decays via the weak interaction even g 1ty d3w6yr:tthough the neutron and one of its decay products (proton) are stronglytyrg:w6t d31 y interacting?

Which of the four interactions (strong, electromagnetic, weak,jcs i dz0(t) xo*o05xi2zu *se gravitational) does an electron take part in? A neutrino? A prodox5 *x (jzz2 *0ei0utscis)o ton?

Check that charge and baryon number are conserved in each of the decayzv 4ye4)kc f1;b8 t0vulr:bs*ujf 2pps in Table 32- s4publkf pt z41 fy:ve;*jcbvr82)u02.

Which of the particle decays in Table 32-2 occur via the electromaz xmy2tm v :q814d3;t:xy takognetic interactixz1tt m3ytd4k a 2:qyx:mv;o8 on?

Which of the particle decays in Table 32-2 occur by the weov n( ism0jo ur-a49dd*+;vgn1,bdc2di hu) uak interaction?

By what interaction, and why, d+w ()f.y4kb;bjm -mnnq+4lwf o owiu,oes $\Sigma^0$ 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 electromagnetic interac7ijvy+:ippy*kyo, 8adn:e.uit ilm/l8 44l ztion? .aony7 elpk,8vi 4imd u :ptl8ij+4: zly/yi*

Which of the particle decays in Ta: qxf 10 rizs(x6(ijxqble 32-4 occur 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, had no c7*/w)(z ud*be xdromw*m i;vcdm7r(nolor charge or electrical charge, and did not feel the weak force. Cvr*w ( *;dm77dx()* /crwzdeo mn ibmuould you say that this particle even exists?

  Is it possible for a particlub5: h)i arwc0e 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 chromodynamics, would it be possible to find particz13)td3aaxlnw29 n 3f uj qz9rskd3+u les made up of two quarks and no antiquarks? What about two quarks and two antiqua3+91j 2r3wa)un lsu3tfk qzn9xadz3drks?

Why do neutrons decay when they are free but not sezr9i1j-)1 y6gtjccwhen they are inside the nucleusr9s 1) itgce1y-6cjzj?

  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 kinwpl99r t/*+m/ t tzdveetic energy is 6.35 GeV?    GeV

  Calculate the wavelen e)ysv 0bm+t;vs3zv; eno :m-zgth of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protoqrxyp(-3iz nr u*xw* 3u4j:vbns make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolutio .,ozsbi4ls4a-0vb qon for a very high-energy proton in the 1.0-km-radius Feo 4,qio -balsb .4s0vzrmilab 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 32-2 accela n*6kuw )nm/kerated $\alpha$ 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 oue:e0sq * 35 2ziy qcg8tuv2rwdt details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths w2q0yeticz e r 3*dsgw8q:v25uith 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 re3dys. ca..d o/,p0wmiqf8y w tvolutions do protons make to reach a kinetic energyfc d8i.p. msa/d,wy0o3qwt.y of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength ( h t.i-z9kqn +jhkn*,v6 lb*ag$\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m k ; 81v*x3tmzzdnnqc hz 4dk.7e5-xkjis 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 used to house the magnets fo5cpc/sa( :pt qr the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. a: qt/cscp (5pWhat magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes ab n*;s+ena za 23qeqxo0out 20 seconds to bring the energies of the stored protons from 150 GeV to 1.0 TeV. The accelerata aesenq n;+z*x qo023ion 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 energye f wb)mwsh)8(w1 p0zd of 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 atf uh70oo h1h;kz) 6amn the 1.0-km-radius Fermilab synchrotron for 1.0-TeV prot)uo07a k;hhoh 6zm 1nfons? B =    T

  How much energy is released in the j+:iqn- f9o kedecay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is rel) (m oqmvis*d3eased when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produceqb,m -f jj(hmp 1zq:8q a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediatin+i5cs0t5iw s7kf 59g/jonvgig particle were the kaon instead go k g55fvi0s/ +s79iji5ntcw of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. What minimum fy-z/e acbf** kinetic energy must f-*cfyab/ ez*each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy mu(71 .x2l7uzvbayuf3j cb,j jccc- f9p st two neutrons each have if they are traveling at the same speed toward each other, collide, and produce a f jubz jjlf,v13cc7ac7-puc( bx.y 92 $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using Eq. 32-3, given the masses of q7i ndhr87fp/suz9 )lnj3ag, the W andaf9)/p3ir,nsd gh7j7qlu 8zn Z particles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photon ux-eti0hleb /*:j k0ns produced when a proton and antiproton a:t*enxh0bj/i0u- k elt 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 isolated- ke:d7ctc r8g v:am)0*xtysd electron to radiate only a single photon. (b) With this result in mind, how can you k -mgccevt7xday)0ds*: :r t8defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of thb*8gz4x q jj; +vwtgy5e two photons produced when an electron and a positron, each z8;g 5jgxyj+ 4w *bvqtwith 420 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 reactions and decays aqs *9nh eb. -c5dp8wsvre possible? For those forbidden, explain what laws are violated. d h9 nv8.*qesbc-s 5pw
(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 t6mu.+i1d yknbb 7 ku8jhe 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 kinen1 0xhdslis7u z3y0ox4;g gyrw,u/u/tic 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 thorb0ky+y7pr;2nq r : een the lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of the im9)+1tl i3wte/+crfg blm/:im.z swtp ;z-w $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of thec;;cjcqfo 5hn w y2-,l $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncer25jooasx)kw. tainty) 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 possiblc 4d )p-uv7ma4:o n ctk64)pey3ovvxde? For those that are forbidden, explain whichmyvc k4xeo d)7pd:a46)pvun3o v -c4 t laws 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 can form (a) a neutron, (b klf91m)ua +n3gr8a dh) an antineutron, (c1a3nk8u m+h9ral )fgd ) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations produce jo 1.v02o)-k3owrh 6spq/pq qiz,sy g: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combination needed to,bw ,k3ytkjm; 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 quarksn jv(ze+umr (6 (as in Fig. Below) for the reactionm+zr uv(e(nj6 $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the ricn7xlss 24xim ,,)rceaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy o9dkl64fle; we(kj *u qf a proton whose kinetic energy is 25 GeV? What is its wavele ljkq9eedu*(4; lkf w6ngth?
$\approx$    $ \ \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 with a gfqu2/e3 yoe)n energy of 150 GeV.q yeu3og2 e)/f 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 reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and p qp py5*)vso1g :fp:;tys:qoa positron annihilate each oo;:yps :ty*q v1)p sfoqg:p5pther? $E_{\text{total}}$=    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 interaction could thex yszb( :lfls25,7b (izbss1y 6cqs8nrb :k:r y occ1 y:bbsys bk:xfqb,:6r (sznli852(scl 7 zrsur? For those forbidden, 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 w ed6qss, v2/yhhat interaction could they yq 6esh2sv/ d,occur? 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 txy f zz +zhu3g9ojn)) lrx p/.1 .z2thm3n(se$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electrowp.f 7euo4zj /(, gsrzteak 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 reactions, Eq. 32-4, for ax5o +lp5v lu36v(ut vproducing a pion.+3xtvuv vopu5 (a5ll6 $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value f2u ) meb.y:s:-kiiblg or 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 water mol2e xyca j3fz. vh.k8511vc aqsecule?    fermions

  A proton and an antiproton annihilate each other )9y9mix/ r3rbwj mtb;at rest and produce two pions, rr3b;m wjtym)x bi/99$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called usezb+l9 w+2jvzxqm k 4:yf4n7gvqq; ;nification 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 unhg t1 paz(t,/a/k /zproper time, measured in a reference frame where the particle is at rest. If a tau lepton is creat (/hz/,kptu an/ zta1ged 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 missingh, uumh8od6t+ 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 e :ag2xg)vv+b the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of light n+qwoh/ z6ak8 $c$ is the speed of a 7.0-TeV proton?