Give a reaction between two g3 vnj fv h6d5-:mjt*lnucleons, similar to Eq. 32-4, that could produce a v mn:-t5djg36 h *lfjv$\pi^0$.

  If a proton is moving at very high speed, so that kx)0x(cza d.u its kinetic energy is much greater than its rest energdk.ca xz )0x(uy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticles t8 (ccp.nvlb ko44n c2ra:wou 8o the constituents of normal atoms, consist of? Wc.rp82 ckob u48(4ac: nonvwl hat might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic3will9lz d74 frsszb8s 5(4lv interaction?

Does the presence of a neutrina.qm8+u ww-; vhagk a;.r2)c0t jgfvg o among the decay products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via the weak interaction p0g m vqcw 28.;+w)uaakgafjt - gv;hr.roduce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction even thoughp8s/)je)zy p go:4b/f )qdhlh9zx .g y the neutron and one of its decay products (proton) are strongly h od4yh) b8sp:9zfzgy))qj/ p./exlginteracting?

Which of the four interactions (strong, electromagnetic, weak, gravitational) d4s9:s.aqv.6xej ow fb- jpg5ioes an eogp9vi. .s-s jxw bqj5ef4:6alectron take part in? A neutrino? A proton?

Check that charge and baryons) kl+g-. h86jq/tg e.-m wuo 5cypdof number are conserved in each of the decays in Table 32-2.kdmgjo-.hy)p-qf/u. 6 s l c5 we+8tog

Which of the particle decays in Table 32-2 occur via the electromagnetic se+9 i ;ponpkng 4,/sminteractiio9sp/ snge n+ p,mk4;on?

Which of the particle decays in Table 32-2 occur bb9ua 2e+6 (+enizce eyfnbq6:y the weak interaction?

By what interaction, andj6i nh73pwu tg*97r 2ysu8wa s 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 o f05k tafv5x.w7eiv 6s kaz9*ne i:si*ccur via the electromagnetic interaction?5*t6 sn0*a sw5eeziivff 7 vx:a9kk .i

Which of the particle decays in Table 32-4 occur by thek7dt+8tv,b.hx 6drzb 9vh x;w 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 tcyo/4y. o:x hcolor charge or electrical charge, and did not feel the weak force. C.: yy/ho c4otxould you say that this particle even exists?

  Is it possible for a pa)2q xmgtp0dl. fgbfov5966k wrticle 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 it be possible to f(rf p5rx*ofto()a*s ;o:ryxe ind particles made up rxsa*5 x;ft( oyo(*orefp:r)of two quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not whenjth2;jujq:.g w5ogs. u1s fem0/s jh+ they are inside the nucleus?w /.quh:s2;u1fje jogj jgs .5ht m0+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 kineegteq4a+ 59rw tic energy is 6.35 GeV?    GeV

  Calculate the wavelength of 32( *cr ieeg6kb5-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which prop6v )tx5xk.m htons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution fort,wo8t aihwxjno3 581z i1-i h a very high-energy proton in the 1. ohtwj8w,385 -1niazxo it1ih0-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 acc9y/tjdhi/g.jv 4c b/f elerated $\alpha$ 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:xrorf sruc3dxy8rrp * ;3318zf0 +spz 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the sizedc 3fz+rs8xf13szr rx 3p0p8o;ry*ur of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the 7+1ieusw u* 0sy 5yqctdees of a cyclotron is 55 kV. How many revolutions do protons mak70c*y yq siw+1etu u5se to reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength kk(p9nc ta:x/ pk 0r.z($\lambda$, 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 deut134 g axgu4nkferons ($^2\text{H}$, 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 houlv;/2 w yd-fnise the magnets for the Large Hadron Collider (LHC) calls -l;i /dwnv2fyfor proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab(8 j ruupls-+a5cir3w 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 prot3( -uriwpa8jurls+c 5ons 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 (cha ej.wtvb(f* omyo9,l14 gcew:rge $e$) 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 Fejboc8tzfc3,, *dh4 o wrmilab synchrotron foo3,of4z c8*bhwjc, t dr 1.0-TeV protons? B =    T

  How much energy is rele jz55 c-gdcfdzw),ajr)k2 s(t ased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released when(2*:yl nwedty) yh eg4 a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neut1xqz edg76p,v u oqm;/ron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating partic:sxy ) -.mbgqfle were the kaon ins.f:g- ) yqxmbstead of the pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each oci*ch)p.p*w ,ryg mj:ther with equal speeds. What minimum kinetic energy mus: *.hrij,cy )w*mgc ppt 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 each have if they arh;vz puex i40fy d.e717m6 teee traveling at the tu7e ;ei.x6 4h0feyvm7z 1dpesame speed 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, given the massebuc 1w e c6-da6ndd,q9s of the W and Z pbeu6c q6-n,d91ad dwcarticles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced wx*3em (e d(ctij4cu (jhen a proton and antiproton at rest annix3m( ecdu(* ct4iej(jhilate? $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 impossible for an isolate j0pofsgwpmmj914y, , d electron to ram 0,m sg9yppw4j1f, jodiate 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 the 1093 znb:f-wenikxdv two photons produced when an electron and a positron, eachn-b:xv3zfdik0ne1 w 9 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 and decaysd i*) 4bepw6n 3popn*t are possible? For those forbidden, explain what4)3i wb6pe*dnotp*p n 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 enejgn ug,uy ed ,c +xm*6 jvf0*4l4wpa7lrgy of each 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 kinetic energy of nh) t(9c,vbqpl2 ib f 6 e.6jjns37pgrthe 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 ncd t0jb e/1a-the lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of tgo ve+, 39c(gy+qklr/h2qbbd he $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the mfyaip+x4 * ,b$J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) or10qac.i ixue9 ;sh+ vv sq;;hf
(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 decaye v9ihe5b1srpd8yk *lpa5g,+ s are possible? For those that are forbidden, explain which laws are 5 rs*ve1a,8k +5 l9ppib hygedviolated.
(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 antineus fzqa /*vrd2ihwml.;4;d3idtron, (c) 2 z4.f/;r* l3ivishwdamqd;d a $\pi^+$, (d) a $K^-$?

What particles do the following quarksnplia+u aow:+)qr8va0/dh ,3m z zh 0 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 prod;57ls4u2jnne s y:rn7b: 6yn3k ufd cew8vv+juce 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 diagrah6,i8v hsmnfr ui/t0+jd:9 t bm using quarks (as in Fig. Below) for the reaction i:jbm usr/vh0+itd,h6f 9 tn8$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the react)rgasleej, bob8 r1/6ion $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kineticcuj jfn jc/3106rv .pc energy is 25 GeV? What is its wavelpfv c1n 30j .r6jccuj/ength?
$\approx$    $ \ \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 ener q oof(6adg3+tgy of 150 GeV. If they are accelerate6otq g3(df a+od 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? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a positron annihi7s7 j txw(nod839 kpmdlate each other7sx8dtd( j3kwp 9mo7n? $E_{\text{total}}$=    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 followiskhewpcn+l tgf 9) 0 5b1-sfg3ng reactions are possible, and by what interaction could they occef-cs l+3t1)ngk gsw9pf5 0bhur? 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 interaction could then7 xfev;efps1a 6 7uw7y occur? For those ff7 xvafe 17 u67snw;eporbidden, 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 7gt1+diw4a go$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak t;kg06r ir jft9heory 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-valuech37pfq -nup*01 b 3 xlbrgu:v for each of the reactions, Eq. 32-4, for producing a pion.g0ux p3 frbvh-7b* 13l:qcupn $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reayv1i-gv1cylpn21y h (k.n+sv ction $\pi^- + p \to \Lambda^0 + K^0$ 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 molecu9b* 9ds5olid(ka 3r kzhd+)bn )yz 4ufle?    fermions

  A proton and an antiproton annihilate each other at rp+ nhgno eb16,est and produce two pions, pb ,eg+nho n16$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification di70 ivzqx-rvj*f 3nl x5stance 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, measux) mnurtn 0/l,red in a reference frame where the particle is at rest. If a tau lepton is x 0mtu,nl nr/)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 :*3f i 3ew/wya txhnf6following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the r93lyood 0 1hkteaction $p + n \to \pi^+ + \pi^-$.

What fraction of the ,+k8cf 3rxz2ags ry1sspeed of light $c$ is the speed of a 7.0-TeV proton?