Give a reaction between two nucleons, similar to Eq. 32-4, that7z eh,1n y/nyp could produce a n h1 7pyze/yn,$\pi^0$.

  If a proton is moving at very high speed, so that its kinetic energybp 7vbaont )f0ab dlal.n)/is 745 va*,p :hyz is much greater than its rest energy750a)*nbd/v,b4 aa yllova. t:s i) 7hpbnfpz ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the ay ba:s7bj2eb4 ntiparticles to the constituents of normal atoms, consist o be472 jbsy:baf? 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 intqf1pan.*l5f 3 tqcs6m eraction?

Does the presence of a neutrino among the decay products of a particle wz4m u.d,::kvuoki,xo01j sinecessarily mean that the decay occur:sx0,ukz: 1i 4mijwo dvu,. oks via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction 8xsaey)dj3 5d even though the neutron and one of iej5day)3d8x sts decay products (proton) are strongly interacting?

Which of the four interactions (stxwcw lo90+3btrong, electromagnetic, weak, gravitational) dowxcow+3 bl 90tes an electron take part in? A neutrino? A proton?

Check that charge and baryon numberdihy8r(g*p/ t7a0t pw are conserved in each of the decays in Table 32arppt dw0/i7h * gt(y8-2.

Which of the particle decays in Table 32-2 occur via the electromagnetic inteb -x*j*uc+bvry s6)fdxwh r0+ractix*b)h-uxrr* dj6f wyb+ c+s v0on?

Which of the particle decays in Table 32-2 occur( qe ltnou;j,9s,:syln om 7u1 by the weak interaction?

By what interaction, and wu9h0vv6s8g1bta0jlidr qf:d t+w 2*hhy, 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),ae2 wg/i5d ykfr/zk Table 32-4 occur via the electromagnetic interactionkk5d//w2z re,ag yf)i ?

Which of the particle decays in Table 32-4 occur by the wny mk:1zgrx2qa) mg .0eak 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 "neutrinlssyxvxbn2 3 nolow 2nx k(090tex ) /)p4upo2olet" that was massless, had no color charge or electrical charge, and did not feel the weak force. Could you say that this particle even e/ 09 2p)l4 luook3s osw(0xx) ntnp yx2en2xbvxists?

  Is it possible for a particle to be bojva4u9hme7tn0a.(5 u onu cs+ th
(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 particl(kk7ib+ z c/gnes made up of two quarks and nkgk 7b/zc+(ino antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when tdgnx:mh)e gzw3m0 .h9 hey are free but not when they are inside the nucleu gex30z nhg9) .whmmd:s?

  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 energy is 6.35 Gs ns(ia .1j++qhip a5qeV?    GeV

  Calculate the wavelength of 35-GeV electrons. E =w*sk6 8tve0ku    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is usjl 50 garpuy97ed in a cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one comp56*nlme b(rb.m, el t q3tk0iglete revolution for a very high-energy proton in the 1.0-km-radius Fermilab accn3.lt m6t keg* r,l5i(b0qmeb elerator? 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 accelerate9 mty gfjz 395mifjip.;t+8 oid $\alpha$ 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 :hpj:b vhb c6,picking out details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each o:, hcb:jhb6pv f 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 yla+p 7odw,1 v.d8gpnjar.; pkV. How many revolutions do protons make to reach a kine,pd8 ;r.a .1+nwgyp av lpojd7tic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengthc 218 evjy76dkaiamg, ($\lambda$, 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;ui+-e2 vi7ct;5 bm3 do cifo* by(zts ($^2\text{H}$, 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 wilo4jmvrd79 r s+l be used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magj4vsmo9rd + r7netic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds;0z tu vy5gmd y348sz c7x(3 ouqna()ei; khkq to bring the energies of 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 ;)y 34 qh7 3q0akms5ezyzgiukod xcunv8;(t( $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particle (chargewegp8oxq 4m3eciccs 5) ,zw)0 $e$) 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 tnj:0c.alvzm k0 8a. c)zg )o( obuk6 )doaobr2he 1.0-km-radius Fermilab synchrotron for 1.0-TeV prc))okd(ln a:2za oj. 8z0o bk6mor. b0)cavgu otons? B =    T

  How much energy is released in a7px2-myg xeqf9 6sss,il uv0y l0o(5the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released whe opbpd0ei:y18x -xl 0yn a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a nhu irph:;0qh ax q22u+eutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating partipjw68e dcx8 nqu (w5g.cle were the kaon instead of(e6ugpw. 88qnd jw5c x the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other wiagek8e2 u 9udupf9d+q m +4- a/wpai0oth equal speeds. What minimum kinetic energy m/ +ua2w-kfo9aug 40 pe9duqi8dea+pmust 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 6x / k,cn2msllhave if they are traveling at the same speed toward each other, collc/k6,n2l xml side, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using Eq. x hd;n;by6u8ves8gs m 3zj98s32-3, given the masses of the W and Z particles as ab ;x yms8j8hv ;ssg83un6zde9bout 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelength zy t/yl.g9-s)kh mx)hs of the two photons produced when a proton and antiproton at res ylxhm s)zy./)g-hk9tt 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 momeny vce,0tm0 5sjgi5;ga tum and energy, that it is impossible for an isolated electron to radiate only a single photon. (b) With this result in mind, how can you defend the photon e00vgaj55m ;i,gy tcesxchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produc bz+;1hqgybb y (d ybp-2j8st:ed when an electron and a posig;pbyqtj8z 2b b+: ybh(-1sydtron, each with 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 followi k gg80kv-69 8c(e war7ucxabing reactions and decays are possible? For those forbidden, explain what laws a c-08rgc aiguawx k9(e 8kb7v6re 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 ddk j-:k,/wxw 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 eleh.5axfc422so o:w* tw xl4wv jctron 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 thl-e(ht m9x2;tlsi7qxbpz c6pg) 1*ed e $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of xh2kyfju/ )f4 the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of t1v3 8uc9nxki rhe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy widtab)/ys+ 74/obh4 pk d0 d+g on/ys5ttxnpl:vzh (or 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 possible? For those that are forbidden, expl7phu643 sozvc6 a3cb bain which lcb3u4c6bhv o3 a6sp7z aws 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 4y73q ydex;eycan form (a) a neutron, (b) an antineutron, (x 37qde4;yyy ec) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations produc/4zlv z(uei (se: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combinatiaqb * kv9mu1f;on 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 quarks (as in Fig iso8 n+*o,jra. Below) for the reaction j8+* a,si rnoo$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram foriw(wu8 pmmacz7 c)a; 5 the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a kvh4z2/n9rh7: k c xb6irsuv06z2q iwproton whose kinetic energy is 25 GeV? What is its w6hr v7r v2:/i zzk4 w9chus k62b0nqxiavelength?
$\approx$    $ \ \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 intis83,djwy ul7t+e1 xaio/+n go 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 do they travel go+dity1sxej3+ n7auil,w/8 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 annihilate eaa g8, pgaxlg+ou3vb h ssg8i5+,:md1qch otherg,upxog88hvai,: +g+ slb ma3ds q15g? $E_{\text{total}}$=    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 reacti*e k(0 2uga09w rolp9ses;hyuons are possible, and by what interaction could they occur? For thg r0*aeu0e(s9pu2ly w 9k so;hose 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, anag.u7 :kg+oudd by what interaction could they occur? For thd+uoug k. 7a:gose 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 3e bb9ij mfu;f2,f(v-u1k 3e tmp5mt 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 electroweak theory at abn+,:x 5jv*psm4xq uy oout $10^{-18}\ \text{m}$. 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-valuem9j otp; h )*bcf*n 4 ,2w5gytq.xotfg for each of the reactions, Eq. 32-4, for producing a pion. ;f*gbop,fmow .nttq25t*c9)4 g hj xy $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value a+dt;up 3vzv:pta(k 7 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 water molecu21).gyg uiykhb53 pp cle?    fermions

  A proton and an antiproton annihilate n b -eyj*6oxz*each other at rest and produce two pions, ** 6znjxe byo-$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unifictaq;as 6 a,o4 jvs51fdation 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, mea99o(cdn0a*ab,cl kkhsured in a reference fram(d0c lhnkk,9a ac9*boe 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 particle in)l2rybctct;6 9v6nc/ i ou4om the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model t*9lsr,d8niv, r a0wyz o describe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of lighth0l y)4*l9 oz+c2/fruguurx *o n5mnz $c$ is the speed of a 7.0-TeV proton?