Give a reaction between two nucleons, similar toepjf). h(k8fu Eq. 32-4, that could produce a juf)8(.pkhf e$\pi^0$.

  If a proton is moving at very high 0qtd em004luu5wa.s cspeed, so that its kinetic energy is much greater than its rest energy ca0t05u .wdls0qe um 4($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparuynwh8p ; crc)1zv3-ab-t j7cticles to the constituents of normal atoms, consist of? What might happen if antimattejb 1 -zc7v83ch nyt rwu;-apc)r, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decqf*d wxj)5 c-tezmf5yc(1nnm d:q )zn,vv *, cay signals the electromagnetic interaction?

Does the presence of a neutrino among the decay products 1tl rhhf:arlw5m -j,+of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays vihm ar-wh1fl ,+:t5rlj a the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction et+ nk2 yo3ahw:ven though the neutron and one of its decay products (proton) are strongly interactina 2oy knh:t3+wg?

Which of the four interactions (strong, ers-z 0,qxn rx9lectromagnetic, weak, gravitational) does an el9xzr,q x rn0s-ectron take part in? A neutrino? A proton?

Check that charge and baryon number axblz/6bk g-4a, lsc)d re conserved in each of the decays in Table 32- d al,b-g)ls/z6 ckx4b2.

Which of the particle decays in jzf9b.p is(/4vethk7 gzc)m-2cz f; qTable 32-2 occur via the electromagnetic interac- ;vfqt(cf2c )zzhz79 j ibmk seg/4.ption?

Which of the particle decays in Table 32-2 occur by the weak interaction? ds9c/ ap( toe6:kfr3e y6c-h w0iw4 ttk5w0oz

By what interaction, and l ft3;tj(v,raf02xi;j.fhja 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 eldxp2 jhhrle.(9-y ,uoectromagnetic interacojy 2rud 9ephh(-,x l.tion?

Which of the particle decays in Table 32-4 occur by the we *ua7o(m5585 b8wt rvhndgkxp ak 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, hadg i4lax/wp1 perfq )yv). ;;pm no color charge or electrical charge, and did not feel)vayilp; p./regwqf1;xm 4 )p the weak force. Could you say that this particle even exists?

  Is it possible for a particle toewl 0/ *1hdlcas-5jlo 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 it be possible t3(h3 gfeqy 7lno find particles made up of two quarks and no antiquarks? What about two l ney(37ghq3 fquarks and two antiquarks?

Why do neutrons decay when they are free but not when tmoh2bb8 zmvf)np: fg( 0*zx4khey are inside the nucleubfkmv:oz0nh(xg p82b * m zf4)s?

  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 kinetic energy is 6.35 GeVmiu.fp-snl rp*)37e pf mlm 35?    GeV

  Calculate the wavelength of 35-GeV electrons. E =bl 2(wji6m 0hrit4xfd2q*4u s    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which protoq k zrcd bx:1o4v3+4cmns make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one completmrexd .be in8w,6( ;gw r7di.fe revolution for a very high-energy proton in the 1.w;dwbre (67. 8 m irfngdix,.e0-km-radius 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 ac.t q emtg 3cedul(+h12celerated $\alpha$ 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: 2i /(ls92 w nbtrpzk-h30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleon in a nuck/rlh9i2z - sptw b2n(leus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55e02 ia.- dtxci kV. How many revolutions do protons make to reach a kinetic energidx0iac t2e -.y of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengs hi-wym c01k,fe18v eth ($\lambda$, 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 accelerate deuf w7eh8 q0z0 3+fwxlcuterons ($^2\text{H}$, 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 hou6jtip uw ;0n :nsb5s;bse the magnets for the Large Hadron Collider (LHC) calls for proton beams of energt ; busw;ib6jp5 n0:nsy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab T j,fr:klwo) /jevatron takes about 20 seconds to bring the energies of the stored protons from 150 GeV to 1.0 TeV. The acceleratio)kj:lw,ro jf/ n 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 of a particle (charxl))*k.o-( k z 4pu6.dqh6dotpz q vlqge $e$) 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 int9i+4;xka c)3ho g)m dd:z xlbbensity is needed at the 1.0-km-radius Fermilab synchrotron for 1.0-TeV protons? B =+3gk xb)aihzd cm 4 9b;dlo)x:    T

  How much energy is released in the decaytkf79s t;rcq,nph xul1a1r8 / $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is releasedcb,x8 n k: x.wm f+/qutack5s3 when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antine7):8hm -aj j pk8l2kcduqvf6gutron pair?    MeV

  Estimate the range of the strong fjg6.gi u5 i7a)v de3**aafolqorce if the mediating particle were the kaon instead of tel5duav3*jfa ia g )67o.i q*ghe pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds.r. lf1rob)*r g What minimum kinetic energy must ealbr gf 1*.o)rrch 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 eac*tkm mk e3j;ab b)13j9sfg7omh have if they are traveling at the same speedebaofj*k1 k 3 mm;s gb379mjt) toward each 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 wr:0iv0n/q2z lsm*)ipgs8 rden the masses of the W and Z particles as about 8mw) 20nd:q 0r i8irpsg*/ vzls0 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the waveleng*(+sssi1zgw 1 qr wzd)3265az*g imhk pz:gqs ths of the two photons produced when a proton and antiproton at rest annihilate?zhzssr wa11wq*m6)sis+d25 g(pq*3gkzgz :i $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 is impossi fyvi)l8sw*tjvt5 / 7hble for an isolated elecljt* wyv )s8tfv5/h 7itron to radiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of ttn gqiv4k/ th g lu.x k*amwjv70k4/30he two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihilatk3qkn/4u7 t0 it whg4jalv/g*.vx0 km e 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 ryxqji);1 mr q m/5vxe;eactions and decays are possible? For those forbidden, explain ;e1m)/5iyj; x qrm qxvwhat 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 produh) f.qp3k bmszp5ly4+o;;hyve c+n r6cts 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 en/n- 1amdl ag8 enm8y9pmsvivbh,:p4, ergy 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 then tpn nzul(gz9sp2i n;j: ye(-en34 e6v lhe lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of the ,bt6mdzs )w hg*osj ;1$\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the ak* u38q4p,wboy 6bac$J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncerk9kf t.q,d0 vrtainty) 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 possible? For those that are forbidden, explbqq 6ummcvq5w2 5n4t 2ain whicwqm u52qm vbt26nq5c4h 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 combinatiot1: io/lzt to mr+yv.;ns that can form (a) a neutron, (b) an antineutron, too ;.yz+/ :t1lvitmr (c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combi 5u tdxm an50fr*9 dnl1y7 cu)kpdg9yd:bpw-4nations 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 pi.a5sysk+)3xytm 7 2an)jve aroduce 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 t:t9asvg hr1 k(t1ox*using quarks (as in Fig. Below) for the reaction 9 x*1rktvo gh(:ta ts1$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram fsjinw-2d a/ *afrn ; fd0sp/0aor the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energj- sj/8b-yc1nav/-ev -z 0 vsdgkyym7y is 25 GeV? What is its wavelength? ns--yajev/vvk 0scyym 8--/ dgb71jz
$\approx$    $ \ \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 wiu(2 3jodrhmx p+i,8oi4q ;khath an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they trav,; mixo4aik(u+8hq3rd j 2pohel 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 electroo (v-uu3 t.1re9bhe8-tgcl k kn and a positron annihilate each otheuc(k-keh ourge9 . 38-bttvl 1r? $E_{\text{total}}$=    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 b5i 6i 2i.e2dlpckaqi 8y what interaction could they occur2a.52eli id 8kiq6pic? 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 ing gz0izyzfq,g: *i 1.j p75fqcteraction could they occur? For those forbidden, explain why. 1 i:zcpz.ygf,z0 j*q i7gf5qg
(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 fzhz0 4au rn71pb/.hg$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the zcjhl)3h q8ax6r8en1 electroweak theory 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 thei/ o;s07py ywe reactions, Eq. 32-4, for producing a pion. /w07o yseyi;p $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reacrm *vi 5-9sisftion $\pi^- + p \to \Lambda^0 + K^0$ 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 ferljq7hw jl 4u;yb uk88;2ipa5omions are there in a water molecule?    fermions

  A proton and an antiproton aky m.1ki p ;tw5pq88vwt;t(lzl- gyl8nnihilate each other at rest and produce two pions, - ( .l8pty km58 q gvl;kiwytl8t1w;zp$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distance r;.c)ymrq2dc : gq q-gof $10^{-31}\ \text{m}$ 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 ar6qtj6uk77- .qmkztgf2a b pf 8e in terms of proper time, measured in a reference frame where the par t28 - f76fubt7mgk6jzqpkq a.ticle 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 reactions. h;dz x.y0m9lp
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe th;xw6cmy2c l c(zz 1dd,e reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the nwz1 btt(-b l6sp:vv1speed of light $c$ is the speed of a 7.0-TeV proton?