Give a reaction between two nucleons, sf7k ,zbk4w vv n,f5.mbimilar to Eq. 32-4, that could produce a zk4 vvbf,7wnk5f,m .b$\pi^0$.

  If a proton is moving at very high speed, so that its kineticglqlh nsm0t fnx ;+9(; energy is much greater than its rest energx 9q0l ns(;;hf mlt+ngy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," mad a .*24yggpnczwdovsm( 60fpg9 6j8jee up of the antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, madfw8 vg4(na* 60gj 6e2zmgdc op9.psjye of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signa01ze3h *8ltujh /ly otls the electromagnetic interaction?

Does the presence of a neutri;+35xr yzh-dwn hfoi;3 g;e cmno among the decay products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.dm3g+ 5-e3;iczhx;w;orfhn y

Why is it that a neutron decays via the weak interactiono*jc:d+ tm.l9vbob 4l even though the neutron and one of its decay pdb.l4:tvb9*loj+ o mcroducts (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, gravitational) 3z1jq c:0ist(vpf d9w doessidv z9q 3jc :f0t(p1w an electron take part in? A neutrino? A proton?

Check that charge and baryon nuegy 9)h )gdemtx-,9.kr vo/mclpy1g9 2kmtx.mber are conserved in each of the decays in Table rce9kmtg). v-y1.gk o)9xemxhl dm, t9 pyg2 /32-2.

Which of the particle decays in Table 32-2 occu*; /tyw d,77 oqq*dt awznfgr8r via the electromagnetic interacn 7/tt*awq;qzr7f8d dgy,o w*tion?

Which of the particle decays in Table 32-2 occuy-kl(:ok;o 6kncfd5);sv hmh r by the weak interaction?

By what interaction, a x6ce:phodk(1 nd 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 in Table 32-4 occur via the electromagnetic intera(+t,nur4qc ixqln s12cti,xrq4n c2 tslu1qi (n+on?

Which of the particl8axj)+mz:hopvpfzra;1 55or c,wg 5d e decays in 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 offu62g w.o8jgb2 ip(kg "neutrinolet" that was massless, had no color charge or electrical charge, and did not feel the weak force. Could you say that this particle8ug2jgbp(.2wof6 i gk even exists?

  Is it possible for a particle to be elts g955z.zgis / l9wboth
(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 chromodynamys0jsyn-t 7hw-gj(:r2ot 0 spics, would it be possible to find particles made up of two quarks and sw:2 ohsjy -tn0j07s rp-y( gtno antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay whey+c-se0 d :3kquyui (qw lue,z(9cvn/n they are free but not when they are inside the nucleu/ ,lv quud 9 k:wz(e+ccqs-yu30 eyn(is?

  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 enerqb*9 /yhjjesu s0lzv/mi +, 3h;t jot:gy of a proton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of k 5k veibe/ ip7*,5qnhnx: c8q35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in zke39v52yw +fj bzyu t1+x,mi a cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution forjb-qx+,wucjqpk yf ; (:tft 73 a very high-energy proton in the 1.0-km-radius Fermilab acceljt(;cfjbq7:kuyw 3+,p- fxqterator? 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 Exampleuuh kdo,gls pdz3q480c6ldrc1b ,.)w 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 oup k t+b; t7cqw)rc(on0t details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each otc+70kn tqwr() ;cbo pf 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 in wiu o;7/rts8s 55 kV. How many revolutions do protons m7w8ou rnt;/siake to reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength*ohkp86w2 vwh ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m 9 -m8r)s 87lykegngmb 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 that will be used to h 4qz ;s(y;dswv an3l:t7pmt5bouse the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy;vtzwldns tqb(5 apy s3:47m; 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes aboutdw (e -ezf.;o fp+m,av6)qddh 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 essez6 (+dpdf- ;m ev)h,fodq aew.ntially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particz;7c:b r pdpvnvmj +p d0-4 p:-pahqs2le (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 needehjoe)t*cjhq6sp b ;bgp4x 7: -d at the 1.0-km-radius Fermilab synchrotron foxs:j;b hb - )c 4ehp6p7tgoqj*r 1.0-TeV protons? B =    T

  How much energy is rel/as: (uz7szz0f 2*k tjy3saxzeased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is relgq f)5f 8+jvxso0ts8feased when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antig1swo2 3z9 tozneutron pair?    MeV

  Estimate the range of the strong force if the mediating particle were the kaxlapuw 1wt4( ra71k( gon instead of the pix w(k lt(7 wpua1ar41gon. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other wi gc4 acl.9hze2+ rbg*jth equal speeds. What minimum kinetic energ.e cgh 2rag49* bclzj+y must 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 ea)a x47c-tbhspk g7 e6lch have if they are traveling at the same speed toward each other, collide, and pro-h7ce xa tsp 4b)k7g6lduce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using Eq. 32-3, given the m ghc,f6 3 gqatd: pmv48*rj*lmasses of the W and Z particles as about 80jm 6lm d,3v r*ta4fgpq*8 hc:g 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 and antiproto(lhcg(e;l kqaj t64gkpq1 (g6n at rest an(j gphlk gq4 tqgle6( ;6(k1canihilate? $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, th,): vltq2cl : vojb*hxat it is impossible for an isolated electron to radiate only a single photon. (b) With this result iq* v)hbvl :l t,oj2x:cn mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengt(md3mqi65a :gl oh/ t2d6p onqhs of the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, l6/qhqda5og6i:2mpmto( 3 nd 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 posh kr.k9h )byh3u q*u:qsible? For those forbidden, explh: *u)qq r9uby. h3hkkain 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 energy of each of the two py5 ua3g--v h/12k huc*mssai-lpm1t hroducts 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 thw2nsrytjdaig ,7 +h a,t 5:ew)a)o,zze 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 estimksup x3p5 k4pxo 3x53oate 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 tha 3 s hkuaei0b7ou4w(-e $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of t z9l/ofd i)l//au-d,vh w( tqajvq ;:rhe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) of (l*:v bu/ z w6o pfjq1cbfm(d8
(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 ty+ 3dxv4 gu)rrhose that are forbidden, explain which lawvr ru+4gd3y )xs 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 form (a) a neut hqar 8+,so5vk dfhx72ron, (b) an antineutron, (c) a r q8 o7va2hfkh ds+x,5$\pi^+$, (d) a $K^-$?

What particles do the following quark pl9,j er2, tfb:wt6ehcombinations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combiv cnw/58n-srn qx q1r(nation 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 y./0 pps: wbxvFig. Below) for the reaction xyps/w.0:vbp $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram fe 3lfa03qx (bvzx yj)zu0 b-c6or the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic e*:i.t*itej /a);tdyd*soc9jr q eg6hnergy is 25 GeV? What is its wav9ad cr; hjie*tjt:d).i/t *s*ge6 oqyelength?
$\approx$    $ \ \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 energy o-t itf s+7z9-psg-ggmf 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 TeV? dg+ig t pz7-f-t9-ssmg$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a positron annih -gvoi;cg0zpia pfs,ofim ,w ( k),-i+ilate each otw+og0;fi- p(ak-mz vio )i,sc ,gf,piher? $E_{\text{total}}$=    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 5ib :pesqr k/p.v /0(glusb6d2w qv2n what interaction could they occli/ uqn5se20k sp(26:rqbw.vb/g v pdur? 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 possible, and by what interactr m0dt)u 5.f8 +cqpmuuion could they occur? For thos+ .fcqum0u5pm)8 dt ure 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 ah y2zyz:+lh:0 e8q fon $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak thc c0g0/:ngdqr eory 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 ;tcl2d4f t/cpnl,8p t the reactions, Eq. 32-4, for producing a pion. ft4tlp2l p; c,tdn8/c$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-valu/jez : (wvp0dm3 plpqbke 9*e0e 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 molecule lu;i;qz,;s qy?    fermions

  A proton and an antiproton annihilate each other a1khe3v qdo74rt rest and produce two pions, ero 7 34hqk1dv$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distazrnp), awt;dr ey(66 rnce 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;kpagat )ifg(43 7g wc reference frame where the particl; 7gawfg 4tg3c (kai)pe 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 the following reactio zasuh/*y9op, ns.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe th)l .1v (ob5iocjvc bk;e reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of light*a4 lpwcya8fsf y8e3-fl v( d4 $c$ is the speed of a 7.0-TeV proton?