Give a reaction between two nucleons, similar)sinldwnf0)bc( + +;kw zl 0np to Eq. 32-4, that could produce a nz+k sdw +p))ifn (;b0l wncl0$\pi^0$.

  If a proton is moving at very high speed, so that its kinetic energy is2,9x2as1,xpka dwokk5fmj-m much greater thanw ,opj221 -dxafk mk5,m axsk9 its rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," i+4zqvwy zr:, made up of the antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatv +yzi4q r,wz:oms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic interaction o w3/)jb,cgddit4(oh ?

Does the presence of a neutrinomuke-svt ;onut4:6 .d among the decay products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak inter4du;on:t e6su vkm-.taction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction even though the neutrongfjq eg 2s*78wyc: -uf and one of its decay produu*2-wegf :cqf gsy 87jcts (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, z3t;xxex5l a2gravitational) does an xx2z 3xe5l;at electron take part in? A neutrino? A proton?

Check that charge and baryon number are conserved in each of tgtsk5kl;xvq6k-2 , c:kimmmf))g4s mf cc l:/he decays in Table 32-2./; ivf gmskqkgk,mt :cclf4s-mk:6 ) lc)2mx5

Which of the particle decays in Table 32-2 occur via the electromagnw;oca -c al(8uetic interacti(-uo clc8;aa won?

Which of the particle decays in Table 32-2 occ6 :d3p8kz. m7sez( z pehmab-aur by the weak interaction?

By what interaction, ak,ui)k5. 6lhkk l)masnd why, 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 iuus,1jj* ir:nchz: ;pl /h tb4n Table 32-4 occur via the electromagnetic interac4:lj/rbpc z1:i;h,nu ht* justion?

Which of the particle decays in8h5r)tprog 3bb8vp zt54 oid+eh u+ /p 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" thay9l k1 +zw1qavt was massless, had no color charge or ele1azq+v lw9yk 1ctrical charge, and did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to be nvdml8; y+;ubpnn4/j0v g3n dboth
(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 f dk 57fo-upy 0k*giih:ind particles made up of two quarks and nifdyg* i 50okp 7uh-:ko antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they ares61 gxu2yi3qa free but not when they are inside the nucleus2iga1yu63qs x ?

  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 pos9 p5b4y;snj8h1 rch roton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV9e. (zwg9kw(*ds 6rop dea mjtuj*/ p: electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which .tyq,9i/qw:xgeg: wpprotons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revo2 5 +i;9yzjt6sv(xd b7oneccrlution for a very high-energy proton in the 1.0-km-radius Fermilab accelerator d6x r 7zecy(95cbso jv;ni+t2? 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 accelerated( 8if hl8ta(b/pxc 2sz $\alpha$ 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 details of the nucleus: 30-MeV /.znwsgw +2l-4ie sawm m1*sx alpha particles or 30-MeV protons? Compare each of t.mn1ass2zww-ei l/ 4 *gw+mxsheir 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 kV. Howv9,;a jn d/dkv many revolutions do protons make to reach a kineticjv9a/v;,ndd k energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengthu qxid,- 5x7f2 trf)*anbw 4ax ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 i,+ - qvlnld4pe2ojr-m is 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 tt ndpa.y 3d1zn)k07cmz 6u4yqhat will be used to house the magnets for the Large Hadronmc p 0qt.znd 6k ya4zu7y1d3n) Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermizxih/c-:-+ jzq)rz7whq o 2;: citobilab Tevatron takes 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. (oiibz;xw +z -ir2/7qhtzoj c) :chq-:You can assume that the speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy rz.p4 qj pvqcz5)9 ,*)* ltreldhe*8qb) qhogof 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 at the 1.0-km-radius Fer8; hr98djptj wmilab synchrotron for 1.0-TeV prordwh8;jtpj 89tons? B =    T

  How much energy is released in t6+tr3ko 1qt tohe decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy iso(xk*qqr 2d qmvse2l:a5 ha, 3 released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-wveyt8w6 (s+x (w ;w rxd 4qbi)s-cjb4antineutron pair?    MeV

  Estimate the range of the strong force7nipf/6ibz (jdgt9i9 qc*zi 17e db 5a if the mediating particle were the kaon instea /91j9(7bzz6 7fnii ddb i5q*pg taiced of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. What mini)ay*i /ire)gp mum kinetic energy must each have if aarp) giy) i*/e $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must two neutrons cd133t; pa/2 ao.pdivdex/joeach have if they are traveling at the same speed toward e dj/vpo3idx2c;e1/p. daao 3 tach other, 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. 32-3, giv**3 sw0y(vjt bzbt;s 4sexa;cen the masses of the W and Z particles as ayb0;wt*v b 4ss 3tz*c xs;(jeabout 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced whengnx.zcdnjhtx3 +8 v: 1 a proton and antiproton at rest annihilate? nxc.jgn dx81: hv3t +z$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, thapde4y qf4lcv+v6n-f1fph6 ps5fy;: k t it is impossible for an isolated electron to radiate only a single photon. kf4fe-yf sqf416;5ppp:vvdy n6 lh+c (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the :e pg6wv(tj7,fj .qfgtwo photons produced when an electron and a positron, each with 420 keV of ki (,w egqvfj7 p:g6f.jtnetic 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 possible? For tdn:, 0of/xlhwhose forbidden, explain what laws are viwxf/h d0,n:l oolated.
(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 eachm8 9l/oo7ag1nxvj h4xf88vay 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 kinet 6f.x/fp4nx9a80b1 m twvfr moic 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 the2 0rlqo-)uaydmx +v s6n 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*lkuj :e ,cpubi3g-xi.lc/h. $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of + :c6qdsjwvna fwg693the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) ofo0 py.s /n iykhy5y0v3
(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 u8ck4 z8 -pfomforbidden, explain w84zu8f- mcok phich 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 fo dp x rx-e /a1w-rbnuo+c033czrm (a) a neutron, (b) an antineutron, (cnzdrca-3er w b3p oux+-1x/ c0) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combing63.rux 3k- seew73ladz*f an ations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark comb7c-o8 bcq dr+nz)ah8nzvled+)fxs * 8ination 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:(sf8i5 jy (hg nhvhm)am using quarks (as in Fig. Below) for the reaction j(hvi hmh5sf:n (8y)g$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the reaction v h09.87pzlh f m;zquh$n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetifr 1mepr0 s38xc energy is 25 GeV? What is its wavelenemp01r xr3fs8gth?
$\approx$    $ \ \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 h s) :rauc))wzwith an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and approximately how lona: )hw)zr sc)ug does it take for them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when 6 f od4qnc8-fran electron and a positron annihilate each other4fdnq fr-oc8 6? $E_{\text{total}}$=    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 cou+1amk e5t i.ahld they occur?+ kea.t5a i1hm 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 possibs,9 d esomd/ d;1-tlbale, and by what interaction could they occur? For those forbidden, exp/ mst e-od,1;sl9b ddalain 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 a1v.. 0wxxy 74gm dv7 wlhqgyi- $\pi^+$ 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 abo xb+si .y7by9g jd9ca0ut $10^{-18}\ \text{m}$. 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 producin rf+ fj80+gel k6b:u9d8oqnx hg a pion. +f8kx hrqe bdu:9 +jo l086fgn$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the rf, h7xfw sz(;qeaction $\pi^- + p \to \Lambda^0 + K^0$ 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 tuq gzo;. bvk u1ad e,7ms)xe+)here in a water molecule?    fermions

  A proton and an antiproton annihilate each other adl38eq8.h hc+qhnm o7 0co b:dt rest and produce two pions, 8:hm8 eooch dqcdhn.b 0 3l7q+$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called ug.3h l )k p0hhcpio*:gnification 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 t1ngik 1v/x hl*ime, measured 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 averag lg1nx*h1kv i/e, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the rn.puoc1 9f6rfollowing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describr,gkoey. ft (m,): ,kc,/ch xf*teq 1htgh9jje the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the s dat;n5fm i9w4w4 7d7j ijno)ipeed of light $c$ is the speed of a 7.0-TeV proton?