Give a reaction between two nucleons, similar to Eq. 32-4, that could prodeq/ aqnuwr62e uk m;u;qh 71h-uce a qu; h 2;mu-qewhun1e r7qk/6a$\pi^0$.

  If a proton is moving at very high speed, so k pqknyv y em0*a aee.-.93.cjq/r )uithat its kinetic energy is much greater than its resq /)rku. . m.v0ineck- jyp9 a*yea3qet energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom)q- nhlssd6+ q," made up of the antiparticles to the constituents of normal atoms, consist of? What might happen)-ns6 d+lhsqq if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electg)s l 6vs1idezrkp11( romagnetic interaction?

Does the presence of a neutrino among the decayl b6vrol fe)a,(4gl. */m qnwh products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interactl lv (gwm)ahb*e/l4rqf6n,.oion produce a neutrino? Explain.

Why is it that a neutron decays via the (h+ sxkia;.v rweak interaction even though the neutron and one of its decay productsis( +vak;h.r x (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, gravitational) dosr4* zr0ly1w kes an electron tayslr w0 zr*14kke part in? A neutrino? A proton?

Check that charge and baryon number,vv z+p.f3sya are conserved in each of the decays in Table zp3f v+s,.vya32-2.

Which of the particle decays in Table 32-2 occur via the electromagnetic intera1qg/o xb)g8*xa sz:p+ gh. gmvc8ghvq+ gg1: o )bpmxgxa.s /z*tion?

Which of the particle decays in Table 32-2 occur b:x*bv4g5w cvmy the weak interaction?

By what interaction, and why, d r )la -2sx9ykmju1z1joes $\Sigma^0$ 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 interflmz tb w:r.7sz*( s0laction?7ltssmrz(*f .0:wb lz

Which of the particle decays in Table 32-4 occur by th /x9c ef .ac(4/prmrcme 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 color charns jyal;x be+ar e44g h-34hv*5pm-ps ge or electrical charge, and did not feel the weak force. Could you say that this particle eve4*e-ex jgbn -pas3a+;5mhpvl r 4h4 ysn exists?

  Is it possible for a partng(-zi * hyz1ticle 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 iq- 4bwf3bij r9t be possible to find particles made up of two quarks and no antiquarks? What about two qua4fb-3r 9i wjbqrks and two antiquarks?

Why do neutrons decay when they are free but yq a3kt7;*qvffk4 .tz not when they are inside the nucleutt z.k 43;*q7afqyv fks?

  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 energ *+cmg.3ugn 1dr dvy(zy of a proton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV electro 7fj 4nm 0/zls(vcht1t0uhv3lns. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which p*dmt+:k-k o2f j v 8v e0et5srd+yuow)rotons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution f3dfk.:jxra , mor a very high-energy proton in the 1.0-km-radius Fermilab accrm da:fx ,3.jkelerator? 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 Examsmwr cv(8eqx(h,c h*- jxv 72sple 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 ou 2kest1+fuz fif-*/wb /jw sw3t details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Cuf/j2z3/s*b w1f-f kiwtswe + ompare each of their wavelengths with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across th u (ms7 6deumbn gr5o56tdm0:ee dees of a cyclotron is 55 kV. How many revolutions do protons make to reach a kinetic e u mr0:net7sodubmd em(56g65 nergy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengb1h8: n o7qn(7aipoqbth ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m jwr7f p 6.zw6gis 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 house the magnets for the sxi bzas;l,cn+/*io6 Large Hadron Collider (LHC) calls for proton beams/i*za6b x+,s soi;ncl of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevizdzk ,0 )*mxsr)w3u(u qrl2s atron takes about 20 seconds to bring the energies od2ws 3(ur*) rx,kzqs0 imulz)f 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 essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy o(ggf o/6t--lr b*ic qivjz:7if 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 Fermilab synchrouhuw3nw9 a6le,w x0,kq +er,0r- /c8tr fh ccytron for 1.0-TeV protons?n,tc wc8-9 rwruek6,+ /0h,fxueqh03 ylwar c B =    T

  How much energy is released in the decay es gq8q6x4:c:j7 bqqnab57od $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released when aie -;ggt 3lhh9 $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutroy fn:irmcr)3) :ir rd5n pair?    MeV

  Estimate the range of the strong force ift:2vw+lvc v:b the mediating particle were the kaon instead of the pion. w:vl2t+bvv c:$mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speiv,njy4pqz12 ny o )vamnn 2,v2*)hbweds. What minimum kinetic energy must each have 42avy2)m2vwbvnji,n),yn1zqh * on pif a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must tw .rqi/ gyzab1h7bl)w4 n87np zo neutrons each have if they are traveling at the same speed toward each other, collid 7ibzry)/ q1zp4. lhwn8bgan7e, 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, given the masses of the 15bin 4kpm)l rW and Z pai1 pb5 kn4l)rmrticles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of tbsw u*mq j:.b xx/i*y/ 9*uulghe two photons produced when a proton and antiproton a* q*jx/g/iuwyublxb9 um. s :*t rest 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, that it ik(/ldww.(dei-q f e*y.v-yl u s impossible for an isolated electron to radiate only a single photon. (b) Wivq(kde/ly. fuwd(e l-.*iwy-th this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the twb4xp;tbirf ac9 nt7 5,4thg*so photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihilate head pgt n;hx44 9ac* tb5rt,isfb7on? $\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 ream6 envdwt/( :dctions and decays are possible? For those forbidden, explai(nvwe /dmd:t6 n 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:6kh,e tr ih*s ,qeq(scw)zen3qw b8 -mdi 2*s 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 dec; yhj*p/ -lc7tda6mro ay $\mu^- \to e^- + \bar{\nu}_e + \nu_\mu$. [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 estim- * ,:dbro6w:wmpuwz zate 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 xu7dr6ptq( )y)vhv e+the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of thda;o 91 fbppr(e $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertair4 gy*/bmpt* rnty) 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 dec /6slwikyv iy f.f3f(9ays are possible? For those that are forbidden, explain which laws are violatei6 kv/yw9( l.yff3isfd.
(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 neutron, (b) an antx6k0rrk9akt a6 ;b;mywh3d6 n ineutron, (c6 nrx3m9 akwd;6trkhbyk06 a ;) a $\pi^+$, (d) a $K^-$?

What particles do the followini ;dkx(.5 di x ut:;tuc,7cxnpg 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 a h;0 sia98lk4lun:dpde xi,q($D^+$ 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 diagr7x l1d-ydp o7,.vd 0x.smn uahltp2; uam using quarks (as in Fig. Below) for the reaction.- u2xd y;xns.po1l,a7uhdpmt0 7d lv $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for ywry;3s-h5 gjthe reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? What is its /-x00jcemm(wh wrez gn3ic1y)8f +tc waveleng0 ym0h n-zer 3(tei wgc8wjm1x+f/ c)cth?
$\approx$    $ \ \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-radh l4 *b kqk8)(vz 4bia2bnbll5ius 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 long does it take for l24 kb(5z )b8qhlla kbivn *b4them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a positrmo +5 k3dun2fol9lg x)e -xzu:on annihilate each ot-x2ko+d) nmzo f9 g3leul5xu:her? $E_{\text{total}}$=    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,q+0ff;aypu7 j1l a qo dict;:nwp.(m) and by what interaction could they occur? For those a ;0u.7;md1( jf+ tiqcopqn:afy)pl w 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 r+(fw8yxst-/+a f)h p5ypgk y i/ri.pzeactions are possible, and by what interaction could they occur? For those forbidden5 y+/yf(p phz gy.ip + aikfrxw-st/)8, 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 p5) (9vmy; -xcmbdnyn $\pi^+$ 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 ab-0:9hg.b la0 xyahprt 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 the reactions, Eq. 32-4, for producing-vhu bg4g0an9 a pion.va4g u hn0-9gb $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-valu)i r0 9hou8hksb x)ev-(67xn i bdr 2wqi9kz1je 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 ix2.:xfbr i1k*ex3b ok n a water molecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two pions, x2pq +ta)w o5m63gmyp,hl9 ar5ot3r2am h p yxmg+)w9qa,6lp$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unificati xmz-3xd;bw yo- l9s7von 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 tl7llq: *im k98(g (kp7ku to hvd8fn9cime, 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 tv*9fgic 8lph:7l( d9(ul nmokq7kk8 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 reactions. ed ad;dy8it00
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describq+g b yp5okd080h w9lge the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the ;uqgirl t;.dh i;;qh5speed of light $c$ is the speed of a 7.0-TeV proton?