Give a reaction between two nucleons, similar to Eq. 32-4, that could .+ghwuvz6fcw *, kdw8produce a hw* wckgfzv,.d8wu6+ $\pi^0$.

  If a proton is moving at verynoy +7cqxs9ta 9w wr/r47w kw5 high speed, so that its kinetic energy is much greater than its rest e7aty c5 7+q9owxw rwswr/k4n 9nergy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the a3lanx ikz h;85ntiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact wix;3lz a ik8h5nth our normal world of matter?

What particle in a decay skn s,1;ln .2hub9x266 v yw6wifnmmqcignals the electromagnetic interaction?

Does the presence of a neutrino among the decay pr txq/mi 6(bpfm23p..eyc 9j mkoducts of a particle necessarily m qm6 p3yjke(txmbp.mic f.2/9ean that the decay 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 t af ,bj32wni6s y*ufd87b a1pthe neutron and one of its decay prod3pufadj yabbf*w6 82i s1tn7,ucts (proton) are strongly interacting?

Which of the four interbbip1 vmmn kqo 6k4t73d 6h6/lactions (strong, electromagnetic, weak, gravitational) does an electron take pah klpi 46od 6tkm7/m36n1vbq brt in? A neutrino? A proton?

Check that charge and baryon number are cpwl3eahol 8tcwn f(;4d/5x+w eyu 5q9onserved in each of the decays in Table/te9awn3l hx c;(w+ywoel q5d5u f84 p 32-2.

Which of the particle decays in Tgt-/nz9eer koc,klj xy/8 6- bable 32-2 occur via the electromagnetic interactekyrkgb o 8e9xnczl-j/-, t/6ion?

Which of the particle decays in Table 32-2 occur by w o2*i3y -c0cw ygxwu1the weak interaction?

By what interaction, and why, doesay(8 xvxxnuk*jx8v7xx;8 bj/ $\Sigma^0$ 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 pp, z;3kikwg;ar :0l xTable 32-4 occur via the electromagnetic interact0 3kxa, i pk;zprglw;:ion?

Which of the particle decays in Table 32-4 occayoq0 ( n7t0ytmw ,p4aur 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 colorsej2t awm9 5*r charge or electrical charge, and did not feel the weak force. Could you say that 29re*w js5mta this particle even exists?

  Is it possible for a )l aceh7d i -jgdc 6:de/d2yxpp;g, d;particle 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 chromodynk06kj h99ix gvamics, would it be possible to find particles made up of two quarks an k6k90 xi9hjvgd no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when t;/ n7)qczsfmz hey are inside the nucleussq)cf ;/ m7zzn?

  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 kibz6(pz z/fn/ znetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV eld.l9mak3s *dn ectrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotr16,r ylvu x ya-cy;5)0shbgnr -+oqbt on in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time fordy xyojnv:):4e:c2 -v x3ihby one complete revolution for a very high-energy proton in the 1.0-km-radius iyn :jo c-2y:h:v d4yx)bvxe3 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 of Example 32-2 l f n wgk6j0.2 ++kammgjl;id70i qp7saccelerated $\alpha$ 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 pickin+0 b,4cq mixgzc 1zo(yg out details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengthz0,xc yqmcz+(b4gi1o s 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 kV. H2.k3v(s lgmi :4 kiftsow many revolutions do protons mafsm( :s i3vk .2ilt4kgke to reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengt 7xbxi.u. d:+b0/pp :wjkect uh ($\lambda$, 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 acz/xw ;qip:jhwwk 1)9p5 nxw,qcelerate 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 ugnja5wq30k)cxg x3e6 e (-(tt icw7fw sed to house the magnets for the Large Hadron Collider (LHC) calls for prf-a0twc7c)(wenjiq(gx5 3t3 x gw6ekoton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron take8d:mvi8+4aa1 dgiwal s about 20 seconds 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 essentia8awli1 + adg :avid4m8lly $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particle (charge p3m2igjcca .87qo w9 f$e$) 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.zbe5 bps,xoe;- 7vuv(0-km-radius Fermilab synchrotron for 1.0-TeV ob u(ve-,p xs;zbe5v7 protons? B =    T

  How much energy is released in th( r (affl;okq;*ga ht4e decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energykske vn 62+xjs5v qr*5 is released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron pair?5l/ki* jb*3 1zqn leci    MeV

  Estimate the range of the strong forcd5gc2- al2:q x bck4t.lb5jq o4e8cmf e if the mediating particle were the kaon instead of th2bcq k2q5 ec.4o-5ba:4lxd8 ljg tfm ce pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. Whatgb0rr; ln7tivrmjv b8e-tz/h e:xghx w83.; 4 minimum kinetic energy must each have ifr/ irvv-.nxbg:4 8 r ght7wt;0xm he3b8je;zl 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 traveling 3.,ec+/ry 5sriy lu( 5twhqlwat the same speed toward each other, (yi53c,lr ryh.s u/wqtelw+5collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force 8 iq)av::i yvpusing Eq. 32-3, given the masses of the W and Z particles as ai8v: y) :aqpivbout 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced /o ,(f+ugny m651w,mlxpk 42marrsxawhen a proton and antiproton at rest annihila,m 4 alm op/26y(sfg1xrw m nx+,rak5ute? $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 momentum7l9:q,c ammhovu 2dx9 and energy, that it is impossible for an isolated electron to radiate only a single photon. (b) With tdu9,mlq7 :hv9cmx ao2his result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelenodt+opbky; e0x5+b 3qgths of the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, an3oybdobxq+ e +50t;pknihilate 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 possible? For those forbidden, s;7lp+-y 8*kb(yccn o.lti qnexplain what laws are violated. y yo +ncnsq.l;*lkc (ip8-7tb
(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 products in the dec7dt;(te) aky/df k/yzay $\Xi^- \to \Lambda^0 + \pi^-$. 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 eleg5dm x6k a50lwctron 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 el9x) vgdr8,rnqm+1up ;lw r :bstimate 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 thf:zw cl1veml1 je1a(. m:(sxke $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width oflo6)eu+umxl 3nz .f7l the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or unc ( ar1zbkmk74mertainty) 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 possiblep2wtb+ecb+2 l m r(r0u.+chab? For those that are forbidden, explain which lawsm e0+rl w2ucb+tr+a2p (hcbb. 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 coai4v: av 6q5jtmbinations that can form (a) a neutron, (b) an antineutron, 5v 4qatav6ij :(c) a $\pi^+$, (d) a $K^-$?

What particles do the follow z;ucw92r s16ru5 unjii8 aut:ing 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 neededvyli5g-o 81;n lf5 ref 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. Below 8ntez .p+dqt0) for the reaction d pte t8+0q.zn$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the reac/ta07lz/ o enwtion $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a h r;bs23m3tup proton whose kinetic energy is 25 GeV? What is its ;3tp3 b2 usrmhwavelength?
$\approx$    $ \ \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 Fermilav*uj4tq5. sggo86x t sb Tevatron with an energy of 150 GeV. If they are accetj6v g sqgsu*x5ot8.4lerated 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 a positron annihilacbfl 8-uh g *qe*(kk7x bvz6apa7k07ete each other?xq( egeb8h ka6acflk z** 0bp7v7-7ku $E_{\text{total}}$=    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 posi cd1l89+gdl )jsv5df4 4gwcv sible, and by what interaction could they occur? Fodvdjsclc dflg4 5w 9i84v) g1+r 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 wh** 1lgs y9r-7ab-rm.fqv :p5/xk bx ezm dm2vgat interaction could they occur? For thos db xgv1*b 9em.g5x/-m-7vp*:fyzqs mrr2a kle 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 kctz v8*ki 4o:$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak th n;+.yowldi4in 0 md+seory 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 c vg(a2fnw. :o)heg)dfor each of the reactions, Eq. 32-4, for producing a pion. )ch.2fv :()ogen ad wg$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-valu2 3g:5yg uuu) )bypwhue 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 thereex bxc61tn9fe0jotul:8gg +: in a water molecule?    fermions

  A proton and an antiproton annihilate each oth 0bawdnzu+ezg,b 0js/xd/kmdcy3+6 1er at rest and produce two pions, /m ze06/1 0sw 3yzbdxgd,k+bajc +nud$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distanrqhqzz 9-g0dwhy0 74, ce -8lsm.s gaece 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, measured in a ht v g-,zmdq,p45y8pj reference frame where the particle is at rest. If a tau lepton is created zq5h,pptjy8 -dmv4, g 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 particlb7pu zl2gfxe 9.t(r*s e 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 react- hzzn:+4zk 3w,srgslion $p + n \to \pi^+ + \pi^-$.

What fraction of the spez l sx(lgmfxnl(:n8k6 2ku):ied of light $c$ is the speed of a 7.0-TeV proton?