Give a reaction between two nucleons, similar to Eq. 32-4, that coulddsslw-g34lky/ )xzi3 produce a dklsi z-/wy3)l43 sx g$\pi^0$.

  If a proton is moving at very heplv 32(6 +fge3qt uqkigh speed, so that its kinetic energy is much greater than its res26eu(v lq+p 3ktg3qef t energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticlesw2o wq-uj7 mamp5, v+e to the constituents of normal atoms, consist of? What might happen if antimatter, made of s 2ww5-, j+qm mvp7aeuouch antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic in0)5vt(nu8zeqe n 18 mc vckviq)m;+lateraction?

Does the presence of a neutrino among the decay products of a h/i9ygke q4gy) v:a6zparticle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? 6v4e/ hi9zq)g yy :kagExplain.

Why is it that a neutron decays via the weak interaction evmr e5bx64+ x8to-k zfh 3o;kl,wuukf8 en though the neutron and one of its decay pro8kk;8oxeur5fu 6 lx+-mhkow 3,f tbz4ducts (proton) are strongly interacting?

Which of the four iny)au:qu ck0fwm;wsm kn87 19tteractions (strong, electromagnetic, weak, gravitational) does an electron take part in? A neutrino? A proton? ky0aww umms ;:fqcu7 91)k8nt

Check that charge and baryon number are conserved iswv. k6(jq2ro n each of the decays in Table qs.w2k (6jvor32-2.

Which of the particle decays in Table 32f;k o* f),stq8v3sbehxq/kf 1-2 occur via the electromagnetic interachffb ,*v fxqtok 18;e/)sk q3stion?

Which of the particle decays in Table 32-2 occuhz50 4vjmgos;5ffv hsh 9hvwfe48(8 cr by the weak interaction?

By what interaction, and d) a(*d bfvl 0ef mkbz8y6) 3 -xxrs5:gxvd(xrwhy, 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 Table 32-4 )2e 6rzt0c1nqnvgi lu .v ;gd,occur via the electromagnetic interactilu6tdgzcg0eq2v,) in vn1 r.;on?

Which of the particle decays in Table 32-4 occur by the weak interactionrwhfrm7x,q)fo8rj - --*u5kq tu4lzi?

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" thqaujr07/l ,qbat was massless, had no color charge or electrical charge, and did not feel the weak force. Could youja,0qb/r 7 qul say that this particle even exists?

  Is it possible for a particl;a rootna *-v(xzl 7a+e 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 possib5,yum7cxfnsctt 57 q4/x, nzsle to find particles made up of two quarks and no antiquarks? What about two quarks and two antiquarks/ sy,ctnx5u 5sxq7mn tc4 ,f7z?

Why do neutrons decay when th,l,c1j4jd :2gojqlp5q a k4 hiey are free but not when they are inside the nucleu5ph,ljqjil 21 jgo4d a:4qk,c 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 ener) ,hpf; nyz0khk/sc w e6:+ynfgy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV w5q30d c :a7wgt,dz owzd nu2 *9g(c(j+wpyftelectrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is; yaps(* jhtq*g d9snkcsz4 3; used in a cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complesd 7 ib:85ebhfte revolution for a very high-energy proton in the 1.0-km-radius Fermilab accelerator? :bdbse7i f5 8hT =     $ \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 Exam(,ljo,iltmmeg+: i.m x2o4ky ple 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 detaibz ) pm/ p)p6pduex6r(ls of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleon in a nucleuspmppprd zxeb 6)u/)6 (.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kV. How many rnz)/u m n6pl:2xqkqlgl w +p4zb w),v0evolutions do protons make to reach a kiw+lq4vlzgm,0q : 2z)6)klpnw nbx /upnetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengthot+.vdw yl y2b8e*, zt ($\lambda$, 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 accelerbf :4tk;5qaj(klg ct3 (tsg)iate 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 for ts*his 0 qk y/ 2hzophcil:mcfh*r80.(he Large Hadron Collider (LHC) calls for proton beams of energy 7.*(c khh8fosh:hzi./prs20 q 0y m*i lc0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds t.0klr. 5r yljao bring the energies of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once per turnaky.r .lr5j 0l. 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 energyvg;iq12 lyr t- 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 intre(rt +uzt9/mkh d0 d(ensity is needed at the 1.0-km-radius Fermilab synchrotron for 1.0-TeV protons? t 9( z(ukhter/d+drm0B =    T

  How much energy is released dz z(yl 4obvra(o0+b: in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy imciie2 d.3f0g c; ja-gs released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antinewev nbkx9alhjwn87 4*y9p/u ( utron pair?    MeV

  Estimate the range of the strong force if the m)e8x szqp7xpx+ 9rg -ep5ib 7aediating particle were the kaon insteab5 9+ere8sqxxp -x7z)7pp g iad of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward ehp2oji4a; /2 (p2yjy t0 ugmmd s.,kbmach other with equal speeds. What minimum kinetic energy must each hyg u;.t2jjso kimap0pd ( my4bh,/22m ave if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must two neutron: i .i1*gw mbo9invo7vs each have if they are traveling at the same speed toward each other, collide, and produce ai7 b1wgm.v iov9ni *:o $\pi^0$ 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 therm3(;2bpd+c2f kcz tpf/z -l waar1i ; W and Z partfal dm3 zpa+2rk;(c bw;i2cztp1-r /ficles 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 a proton+r *tdcwxml:jm oudx1i-10f/ d 1h6ju and antiproton at resju- xh1xj u+0dm1cr16 w*it /flm:dd ot 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, t dkde;/7,.kyz,qom j ihat it is impossible for an isolated electron to radiate only a skyod,7m e,j d ;./zkiqingle photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photons produced whe l7,vh;di bw8rw(2xgd)2fn aen an electron and a positron, each with 420 keV of kinetic energy, annihf7,d;rvb) ad 22lwnwiexg(8hilate 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 a qi ;po3:8ort p1p8njzre possible? For those forbidden, explain n3p8t8oopj ri:p;z 1q what laws 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 kineti-y:y .z)joct,hi 5 y1z ek*smpun, wi-c energy of each of the 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 kinetic energy of the electron in the decard ;r5hjcr tt4n:;3cky $\mu^- \to e^- + \bar{\nu}_e + \nu_\mu$. [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 lifetiyf63wxho q0( ime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of 5io*l3i ncox25n96re j tlv/dthe $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of twe4 p-l y 65vzv4r-oh2 qjxu(ghe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy widt1 x)xvep;)vkhifs wtk:ook9 p)b/y42h (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 po9 epji .jr/ky 3k0ro-sr2)uukssible? For those that are forbidden, explain which laws ak.jpjoy)r / eu30rkr ik9 s-u2re 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 forml.v iy/y:sha7 nr :rp8 (a) a neutron, (b) an antineutron, (l7s/in8vp.a h:yyr:r c) a $\pi^+$, (d) a $K^-$?

What particles do the foll c088 tl cibph+ .hrxu41r+pdkowing 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 combination needed to produce an47v,w; sdl pp $D^+$ 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 quvqjw3l( (sf9j.i9z fy arks (as in Fig. Below) for the reaction9(s.vwzyfifq3j9( j l $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for rzppa- 5 ,gqmd7lb 13jthe reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whoser(ag*47eh c:r b70abd5iceu,wr szk5 kinetic energy is 25 GeV? What is its waveleng4e a(0r 5i7cbckwrs,b 5 hdz *u7g:areth?
$\approx$    $ \ \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 in p84n2b6ugb1 qy8;x cxczvk+lto 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 and approximately how lb;glpxxv8 y+b1 8cz2qn64 cukong does it take for them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released wmd8kg -:i5zjreh 0/l fwt+t f+hen an electron and a positron annihilate each om i-5k+et08h:zg+f djftr/wlther? $E_{\text{total}}$=    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 coufnq;1 0g)+ xu zriebnq9fs 4x9(sojn+ ld they occur? For those forbidden, ex+srq4ong fs uq)x fzxn( 0n+b9j;e91iplain 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 reactjcid+ 5 waf8/tions are possible, and by what interaction could they occur/at+ ji8 5wcfd? 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 9:pc( f n(. xhnbca9vi$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the elm1(rw lnt .s.a+nyi-i ectroweak 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 tnk hr8:iwzsau tr ,ja96/a 1k0he reactions, Eq. 32-4, for producing a pion. 8hwk: ,96 a/naztau0ji1skrr $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-valumteu(;x g*u4 re 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 wjfe*g lu*., es74y9+g ,jcmvre qum 8kater molecule?    fermions

  A proton and an antiproton annihilate each othv;w 9upq8.fj ter at rest and produce two pions, 9.wut ;j8vpfq $\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unificatior xp:7h+:hy yrn 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 propb)2u g9dci d,x;pke7y er time, measured in a reference frame where the particle is at rest. If a tau lepton is created with a kinetic energy of 450 Meu,i92ypdcx d;)7g ebk V, 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 thekd7t5aoxs(o i4-l elf-/2v cl q(p,a z following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe bhmld v tc5 3kj ;*h:6/vnp(zzthe reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the spl:8+i (wyfwmi eed of light $c$ is the speed of a 7.0-TeV proton?