Give a reaction between two nucleons, similar to Eq8 b( p09hqbu3m h+ylcv. 32-4, that could produce a hupy8+bh m9cv0l3 (bq $\pi^0$.

  If a proton is moving at very high speed, so that its kinetic energy is zw-g mkzcizs0 +n//(e much greater than its rest eneiezm (zg/k0 s/+zncw-rgy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antx4j.gb h)6oub0pm2 b3 aebn6 wiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatomb0a njbh 64bxo3m6w pu.ge2 b)s, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic i+9;sgj(b2gf0 twowh.s f3d zrnteraction?

Does the presence ofzx b; ,lbvxwbh0+ic f. ;2fxh6 a neutrino among the decay products of a particle necessarily mean that the decayb.i xbxl0fz62x;whb;v,+ fch occurs 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 even though the nj(seiv6j4 7t q--tso leutron and one of its decay products (proton) arevt 4i 6-oq7l t-ss(jej strongly interacting?

Which of the four interactions (strong, electromagnetic,e5oiv ;f 4f :zw8f/bax weak, gravitational) does an electron take part in? A neutrino? A protofo b vf548wi/ ex:;afzn?

Check that charge and baryon num:s yp;nsm rkd9/1ivt+ber are conserved in each of the decays in Table +/tdr ;iys1n pmsvk :932-2.

Which of the particle decar7cy ub)yz 6mif); f:nys in Table 32-2 occur via the electromagnetic interactionc y76ny ;bmfu)if)zr: ?

Which of the particle dec6u zc st4/f(sways in Table 32-2 occur by the weak interaction?

By what interaction, and why8oiu vk e29vt wzc,a2;, 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 particlqr jov p2-v6fy) fy6y*e decays in Table 32-4 occur via the electromagnetic interaction*pf2fy r ojqv 6yv-6y)?

Which of the particle decays 0xu *+nq0ce j vp)il5iin Table 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, hmy 9d,w(vt:uohclf*p + 9:zcsad no color charge or electrical charge, and did not feel the weak force. Could yo:td(pwzsc mu *9o,v+yfl 9h c:u say that this particle even exists?

  Is it possible for a partejd36*oi7 r5nu hz*g dicle 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 p)b* 8d ;l-kk er5lbp2pped) tm+o-bhxarticles made up of two quarks and no antiquarks? What about two qua po5 r+-xmd-b)p)k;pde*l h8l2kbbt e rks and two antiquarks?

Why do neutrons decay when they are free but not whenyhu( *d7 m4wls they are inside the nucleus myl7sh*4 (duw?

  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 knn3uqtpz9 o 4q6o/ jvabv5f -5inetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV electro/jq:/ 0ysuhjro e-;w c j++gb;s0xljons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protons make9p:k **yvd:n u tgxb+e $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolu o a33o+df+6qdhpzd1 0s2p eg/rfvm7k65eb bd tion for a very high-energy proton in the 1.0-km-radius Fermilab accelerator? qmhz/fd6br1b0+ok dsgd 5 7pa36pfv3+2doe eT =     $ \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 Exampwzb 9fi8s, wceoos0 35le 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 dbdh32dn:;fcoiu x,5 vn 9fc*o etails of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the:c2,b*iduoff59n;vdoh nx c3 size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cy-q8bv65tfws p8 fs5fp 0-bvq(3jjbfsm2cl 4uclotron is 55 kV. How many revolutions do protons make to reach a kinetic energyv0s(b6 s 8qc8bu2tp m- fl4j 5fsp5w-f3j fvqb of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (/jlh.btbf fc ge/4 rs 0zx )v:*wv;:rv$\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m is tqtgo,-jr( ,c gzpj 5*io 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 forn fo; w8+i+mhk v1xez.th2r(hb0, iur the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be requirexr02ze t +mih .biv1ohu+ , 8fkn(wr;hd? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 secondsf418s v xqzag *y5nbn3 to bring the energies of the stored protons from 15* xq81bn3ygz5snfa v40 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 a particle (chard3iaqgf 27hdee d)*sn*l+ sg.ge $e$) 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-kolk9v v:3yfu l91kko3m-radius Fermilab synchrotron for 1.0-klk99ov 1ol :v3yu3k fTeV protons? B =    T

  How much energy is released in th6w7e6cvy+ z 6 pkgqab636p pdze decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is releau2vkhjc2) 7qo sed when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineut2fx8)2 zvokwp-v7jk vron pair?    MeV

  Estimate the range of the strong force if the mediatingxrhx0 m 5xmm hj1r/b(3 particle were the kaon instead ofb/r mxh(3m0jx15x rmh the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other wi5 hd; 3use62 y op2kl2)etdacwth equal speeds. What minimum kinetic energe6atchu 53ods2 )lpy2d;ke2w y must each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kineticf(by7g wq mv )9e: u33mz3grzo energy must two neutrons each have if they are traveling at the same speed toward each othero z3uy f:rmw7 ebg (3m9)zg3vq, collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using Eq. 3+du ,5q eyzwa29ggylwm 0sg (.c86 ved2-3, given the masses of the W and Z particles as about 80 to 6w8dgu y(v2qz.cl,e+ysg 9eg w0ad5 m$90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons producgn u cnx2*s. y3: j+mytb,:luz r5lf3sed when a proton and antiproton at rest annihil ujun5xfl c3by:ty z.s *32+l: s,gmrnate? $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 isolatengn61 h e:e0bhbti;x0d electron to radiate only a single photon. (b) With this result in me0i0t e;bhx:6hbn1 ngind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavel*))ek;v (yitg; uow rrengths of the two photons produced when an electron and a positron, each w oviyke* ;(tw r;u)g)rith 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 are possibwvw+ lc d3uc) reur9e/px0r1;le? For those forbidden, explaindu0)/+xr e3r1ecw ;ulcr9 vp w 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 kinetic energv* ogy:ylk3ekz- 6 pvqxpn8 821dta-w y 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 energj1oqcsw ajln+3 9p:(k y 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 lifeti43kc t, 7 dbftq1a)atmme of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of tha dyeg m/vy:muw(w)q )8r1 h(je $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of *ac fpj 5vpa*+-kmqk.the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy wia)c zfw4ut 6f3dth (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? Forlm1l j 3tnu4b4myy8*o af3ji5 those that are forbidden, explain which laws arbj3mof 8lytlui3j nay54m*41e 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 ne)+ dg2sjynqm7utron, (b) an antineutron, (c)2mq) ngj+7sd y a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations produce: (jd b7p yz-9;iwa) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combinationwh 2sw+3p zc6cg0x. nskl0ma v jbo4r3m5h, 1n 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 diagr i .y/dm-ax(d3mt/tcram using quarks (as in Fig. Below) for the reaction (m. tdca rtm/3yxd/ -i$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram n*z3v-1bwoz p1j7qi tfor the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? What is itsc r u pum2g9zo l(l:d. jbq7f3l0e.nr8 f(s6ry waveloq zgrsur3e( uydf.( :687.2bl m0cpjfn 9 rllength?
$\approx$    $ \ \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 an ev 9/hc)eat14c k 3zywunergy 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 reach 1.0 Te3 zyu)/wac1thekv4c9V? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is releeipj-;,5b 9 f qmagjvr56-rt cased when an electron and a positron annihilate each othev mpgetj;c,5r6ri5j- 9f-ab q r? $E_{\text{total}}$=    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, ezbbtnp* n-/u:hy,j5 p8x hyrq oi(;, and by what interaction could they occur? For thoseh8z pi b*y,un/r-:tx j;(qyhn5, ep bo 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 what interaction could a n+)pdh(4m ya3*jnq zigcn6/they occur? For those forbidden, explaga4*yqjd zi+ hnnm3/ ca()np6 in 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 ,b;h(fmys d*;7vt ofk:)ausk $\pi^+$ 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 aj5 p00gqv)iy;sogaky 2/la0e t 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 eacevz6 .fz3cpga (nm94 0ehka6nb0 nj(gh of the reactions, Eq. 32-4, for producing a pion. n6fgakpn 4h jzb (m 9.0e(0ac3gvz6e n $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for*3z6/ kkzb hyz 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 moleculas sqf9tirw: n/25 0hue?    fermions

  A proton and an antiproton annihila/ 8xss8 : 9tblbfb0bbu.df.kyte each other at rest and produce two pions, .:fby lbb8 8/b.xdt9sbsk fu0$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unificatiea(4c /h -*3w (vnl dmg9ebcmkon 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, me-vujz q82cnx( asured 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 the lab, on average, ignoring any collix28qc(-unz vjsions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the following reactions. w/yk yu566cqox7llv 3
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to des33 ly1v.0mu o* h b.tzalm-hulcribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of lightqz2o w63 ah/ywbw*o7g $c$ is the speed of a 7.0-TeV proton?