Give a reaction between two nucleons, simil6dv)j42e 2d v cai,tduar to Eq. 32-4, that could produce a 2tuvai,vj 624edd )dc$\pi^0$.

  If a proton is moving at very high speec t jg;wc/zb,-tvn ;:yd, so that its kinetic energy is much greate;b,wt:tync;g/-z vcj r than its rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up oflpqu8g a9evqf1 (5 d/y hi8 4ibudb9o1 the antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made ol oyp( igf1vehu1bd d/ 88bquq995ia4f such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electk2git6bii:df zf tk/;5( p3 dvromagnetic interaction?

Does the presence of a neutrino among the decay products of a pary38 zp oow4)gl7g p4ghticle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino?pl go w3z4y)74gp8hgo Explain.

Why is it that a neutron decays vi a3 hngh:2qhd/a the weak interaction even though the neutron and one of its decay products (proton) are strongh2:nd3ha /q hgly interacting?

Which of the four interaeayd .-u *f)srctions (strong, electromagnetic, weak, gravitational) does an electron take part i* srf )y-.eaudn? A neutrino? A proton?

Check that charge and baryon number are conserved in each of xkotil5wp ; zmi)* n59the decays in Table 3;) 5il9tnpw* z5oxk mi2-2.

Which of the particle decays in Table 32-2 occur via they46,;m bw308 climy ck a7lq bpfw:ai; electromagnetic interacti;;67bim: qya0 k ,c4 8wl ail3wpfbmcyon?

Which of the particle decays in Table 32-2 t 10omun5d +u-hkj7jj occur by the weak interaction?

By what interaction, andyx ftr7s 85)d,k7h edt 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 i a+h o-;jkzaa7o.3 wxjn Table 32-4 occur via the electromagnetic interactij3kwz.aaj hao-x o7;+on?

Which of the particle decays in Table 32-4 occ05 m rj2(ehd,b8gcl47drk2qlc gs+xzur 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 "ne5:5(ly k z zms*jynd4gku., zxutrinolet" that was massless, had no color charge or electri(n ym5k uz,*l:jy4 z xk5z.dgscal charge, and did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a particle to b8gda1 us)y- n4tw0qoje 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* s0/ggig2j)ol5ptssa.*h uc find particles made up of two quarks and no antiquarks? What about two quarks and two antiq)sc gp5hg2u*iaos /tjs* l0g.uarks?

Why do neutrons decay whe y5uh ten7 3k fzwi2aps*p1hr-m. 8fc9n they are free but not when they are inside the nucleus?s.yw8 u5c 7fer-zmtfipkpn * a32h 19h

  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 enerl* li/ 3iiv;bagy of a proton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-G9;c0kj/ bi nhdeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cycl wjwk*oj /m30zotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very higt. vaxk*m /9spi41ez ni8 j9ozh-energy proton in the 1.0-km-radius Fermilab acceltes./i94n kzp 1*zaoxv9mji8erator? 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 ac) aibz/iuq7p9p(hx x7 celerated $\alpha$ 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 nu3 qri4 t x, kq;r+x4riqz+by3dus8od6cleus: 30-MeV alpha particles or 30-iqzsd irdy,6bxqkqr 4 +t4+;rox u833MeV protons? Compare each of their wavelengths with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotrot, zpd-)su8ft k8bk :xn is 55 kV. How many revolutions do protons makt:tz8sdp8 fubx,kk) -e to reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengtyw2eb wk s k*h)i/-t yao.(l4kh ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m i-ybc/-pt: rwkhsfq +;s 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 housm;ur 4/+r dkyhpy1-buqlii 0lk0je6-e the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What mag ylp; e0rur kmj1q6-d04uiy+k /lhb-inetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron j ;mbr(yep4, ytakes 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 yb(m;yj,erp4 assume that the speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a parf,d2 geq:mix0 ticle (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 q, o25vrurh ,j1.0-km-radius Fermilab synchrotron fo 5vo2j,hr ,qrur 1.0-TeV protons? B =    T

  How much energy is re.qx,-x3u2g: w v psrdeleased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released when a /-,emjy-qavm/4 itxavb0m ( b $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutrokq8wd8u o7.ean-antineutron pair?    MeV

  Estimate the range of the strong force if the y(0+uhr+o8pbf lua6q,gpti 2mediating particle were the kaon instead of the pion.,l+bp +upyr862 o(iut 0 afqgh $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. Whatep.04 d am uulxfsgi ,khx0*(9 minimum kinetic energy m,mxup*ig shlk 9.040 exda(fuust each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kineticuf k,4 c4puqt4 energy must two neutrons each have if they are traveling at the same speed toward each other, collide, and p4k, uufc tq44produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak forh;ys xskt z8;5o5yq8lce using Eq. 32-3, given the masses of the W and Z particles as ; z85;k 5yo8 thxslsyqabout 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photonm g -kt(+7pprns produced when a proton and antiproton at rest annihipnrg7- kp m+t(late? $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 :pc 2h/ -z +tz.hsuur3walq r6 aur5a5momentum and energy, that it is impossible for an isolated electron to radiate only a single ps 6crta/a5u2u.r wpqhla+ - r35:zhzu hoton. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photog*bj bn fq4b:93pe8mkns produced when an electron and a positron, ee knq8b*gmb pf49b:3jach with 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 anuc w:t;*kq q9c; mkwd+d decays are possible? For those forbidden, explain what lwctq:dc9 k+ kwu* q;m;aws 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 products in the deca- f*2d67xcdciumayl0zgz 4(z y $\Xi^- \to \Lambda^0 + \pi^-$. 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 thedr7.y 7rxtcaij8,f i: 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 t+tr 8 3cguucs- rpcg1-he 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 the u-xgkaxxbvsu; ;4zw83* vtv2h9lx vd1 c o:f3$\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of th2 4gpanlroxjnbbye *23si9 i*we;(2k e $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) of p au 3t/ b)o+x.wm:hll
(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? Form7f-;nae 4z9z*nm z zl those that are forbidden, explain whz;l fm 9 z-z7nanz*4meich 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 form (a) a neutron, (b) an antineutrbc15a x 13w4r+ om vbeszsi.9ron, (c) a r e sxz4m1 abc35wr.19sobi +v$\pi^+$, (d) a $K^-$?

What particles do the following quark combinations prod)bp08u u5xd kvp q:k,7i*ehxnfx4i: cuce: (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 producj0v xj.xh +a 78fzmjz))hlm m7e 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.2bvif a0 //nqu Below) for the reactionuv/iq/ af2b n0 $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagradkf;li c g9o- (i,oblrpe/ 5dwh) ab37m for the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a protonfksoi h24p*5(ddl l2y whose kinetic energy is 25 GeV? What is its wavkpsddl52iy ( 4oh*2fl elength?
$\approx$    $ \ \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 witg5s vt4g . rnudx;(:wd5+bkg hh an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how fahnx grgv;(:t .5k4wud gs d5b+r 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 e /ag +b,/:buypyu*su positron annihilate each other *pgy:b ea,/uub+uy/ s? $E_{\text{total}}$=    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 reactionsjnk06p/i lks) +m 8wnt are possible, and by what interaction could they occ kt wp+mi) kn/s8j06lnur? 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 reactio cwyo/:yp95 pgc)2t ky.h+v)uo)fdaa ns are possible, and by what interaction could they occur? For those forp)yp kw5.:/yvfoccyd 2)gut a9 h)+oabidden, 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 zrug)l:uvp04 $\pi^+$ 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 1lirm.,nqs17v uk8x )6vpk teabout $10^{-18}\ \text{m}$. 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 87umv; m a;t3eiuizr; for each of the reactions, Eq. 32-4, for producing a pion. e;i;rutz imv 83m ;7ua $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reack;7h2r u qld4stion $\pi^- + p \to \Lambda^0 + K^0$ 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 mokzb q: s0mi45,abx+uplecule?    fermions

  A proton and an antipro xt,fv90v v srn4yl:+ston annihilate each other at rest and produce two pions, lv4+:s0rv,n9vt s y xf$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unificahr bwg7e8 ;rg7(pl9ektion 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 ij,iy5ojqk o( uqkmy9, nhg:0;n terms of proper time, measured in a reference frame where the particle is at rest. If a tau lepton is createdoygj:k,q,( 9h5; no mi ykq0uj 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 reactions. zqaax0:no6zg a -l p75
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the reactq,4 tjtnv 4qr v;+glt-ion $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of lrq jo7v170yi ruw;3tqight $c$ is the speed of a 7.0-TeV proton?