Give a reaction between two nucleons, si6p+z xugs jb(7 sj.bkx )iqb;6milar to Eq. 32-4, that could produce a 6k6z;.j )7g (upb+bxsxb i sqj$\pi^0$.

  If a proton is moving at very high speed, so that its hdp:l5 s;me;38xygs h kinetic energy is much greater than p l sg;exs:mh ;hd8y35its rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of *wl:oqk qp/sj1ltz1 yw6.ta (the antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms,: wsk/tt16aj*yl(oqq 1lz. w p came in contact with our normal world of matter?

What particle in a decay signals l;pa)g; csl *pthe electromagnetic interaction?

Does the presence of a neutrino among the decay products of a particle n8uj gk3-i pt*recessarily mean that the decay occurs via the weak interacg-jik83 tpru*tion? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decayw ,uofyx/e+p6 s via the weak interaction even though the neutron and one of its decay products (proton) are strongly inter/e f +p,ox6ywuacting?

Which of the four interactionsrd10- ic oawxldz.9 .-nrhro9 (strong, electromagnetic, weak, gravitational) doeoxi r-1.l0whcrzro d99-d.na s an electron take part in? A neutrino? A proton?

Check that charge and baryon number are conserved in each of t8e (rs,n 1bodxhe decays in Table 3 1nsbr8 ,(xoed2-2.

Which of the particle decays in Table 32-2 occur via the electromagnetic 7f0,b i 9auez 6yu)rtiinteractiont 9ryuf0uae i)i76z,b?

Which of the particle decays in Table 32yk6yqpmgatkln;9 m 8y9/21nk -2 occur by the weak interaction?

By what interaction, 8jp o:i 2eo-m4vg kng,and 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 intetq6l/*ivyh+k ractio qylhtk6+ *v/in?

Which of the particle decays id dk po8) 04scnf,.(sxme ixs),qik;on 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 of "neutrinolet" that was massless, had no color o f)fv l+gm-z(charge or electrical charge, and did not feel the wlvf(-m +)gz foeak force. Could you say that this particle even exists?

  Is it possible for a particle to bl k(6ry 8x hrxjgaeesl;u2, e1r94-a ie 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, wounu11pk +gmdx 8ld it be possible to find particles made up of two quarks and no antiquarks? What about two quarks a+m8np k x1u1dgnd two antiquarks?

Why do neutrons decay wh20sc+cn4 bxu,ncw h4ttw4o rf 293fgx en they are free but not when they are inside the nucleuf 4s23cc4g2fb0,towhw9xx+n u 4rtnc 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 energymk)a:9ck *plj of a proton whose kinetic energy is 6.35 GeV?    GeV

  Calculate the wavelength of o)m 79jg6:lkjqlhhb ,szfb c-++qk 7 b35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in whl *pt8(ce5tj mich protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one comp2g;hvt f ,.bztk-8kac lete revolution for a very high-energy proton in the 1.0-km-radiu-takhgv82 ;k .czf,bts 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 acce q) b kryqsr+zsf;-)4mlerated $\alpha$ 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 nucb,4kgfy.) 5gjzer,:wbuws/ kleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengt wesyg grbk.u:k,j, 4wb5)/f zhs with the size of a nucleon in a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyca.-p9mkf-psfu wv 18 h2*oekalotron is 55 kV. How many revolutions do pro-akhf9p p -* e82uka v1.omwsftons make to reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelengt beimwar l+ df:,9brot(9zc- 3h ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of 1.0 m iso, 2aai2 ixgw-d4v;mb3f;rqh 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 hous*cd1bf * ysika.(9j*b ss ;bjse the magnets for the Large Hadron Collider (LHC) calls for prd9 (jsb *1sa cf.; ijsbsy**kboton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about np5op bk7 . ;jottg-0b20 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 essentiallg.n;t5bo7jk -0 oppbty $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particle (chargecni -81kyszad f,xn. * $e$) 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 lc hb03b)czy :needed at the 1.0-km-radius Fermilab synchrotron for 1.0-Th:zbc)bl 03cyeV protons? B =    T

  How much energy is released in the dyfos 36mzku( k+ydh.2ecay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released w61 l(rce)5*ssu2aktwm7va bo hen a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutro :ff go2kog-2xn-antineutron pair?    MeV

  Estimate the range of the strong force if the mes wi,kp(l81g +i z3(uppjz.bvdiating particle were the kaon instead of the pikj8(pw .zi+lz3 g1i(s,pb pvuon. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading tu rbqee uv),tt,2e.-xoward each other with equal speeds. What minimum kinetic energy b)t,te xruueq- ,e. v2must each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must .bm+d8y(i7ycntp )g e two neutrons each have if they are traveling at the same speed toward each other, collide, acte) i7n8b .dpmgyy +(nd produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using u xh 35gjg bycg;m.n1.Eq. 32-3, given the masses of the W and Z ug. m1;hg 5g.nxb3yjcparticles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two phokgt y83e hl+:jtons produced when a proton and antiproton at re3eh8 t klyj:g+st 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 r jlh0 *7mg dbs21r*bd f:xxx9and energy, that it is impossible for an isolated electron to radiate only a single photon. (b) With this result in mind, how can you defend the pho9j71xrgshbrm:d2xf* l bdx *0ton exchange diagram in (Fig. Below)?

  What would be the wavelengths of the two photonsg768q-s1 t3bnzse txc cl)d;l produced when an electron and a positron, txczs c6;8 sden)b 17 lg-tl3qeach 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 decays are/z zue +dr-x 5bhvuwbsb837y7 possible? For those forbidden, explain what laws as3 7y8 uv /-5u xrw7+ezbbbhzdre 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 energytej4r2cygs* 1ot: qni2o/z.w 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 the electron in the dzxj, om-l5o n)05th wwecay $\mu^- \to e^- + \bar{\nu}_e + \nu_\mu$. [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 the lifo 04+ ndge -7ijt2qreeetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of the cv . ;2/b.ytd9ddqawr$\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of thebl83n orf*y4y $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertawdt;m3e*i2; v4o hz td3df,wx inty) 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 thosgqjf/fn.8b e 8+n spi/e that are forbidden, explain which laws are violatedqpe/+inf/ f njg.88sb.
(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 fotm ef iknl045+rm (a) a neutron, (b) an antineutron,fm4ie0ktn+l 5 (c) a $\pi^+$, (d) a $K^-$?

What particles do the following qua .c4 g s:cq:u95ot9 /rg,d;emnmwkzll rk combinations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark co;p nza cla ,(4yxljok+n4i)2m w9)h cvmbination 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 Fig. Bn3 .(q;p4 kllor3tdx yelow) for the reactionnrl;l(3.p q3oyk4xd t $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the reaction 8f1jhv/2zu ieain)lyn+r/g-nu./ * ul9vanz$n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is-1 o/3sh+mst racu4gt 25 GeV? What is its wavelengtht 4-r1cu h/omgsat +3s?
$\approx$    $ \ \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 Te n9r,j)5 nc*sbbq umu+vatron 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 them to reachbbmu 5jns*u) nc9,q +r 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a positron annikobiu-deb3; m09-nr/x+f dfe. rijg0hilate each g-r 3 refb0/ ebd-md. +kuo iixf09;njother? $E_{\text{total}}$=    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 what5s1wwwh 5q,skbh .y (zkhr/ .n interaction could they occur? For those forbsh5(sr wkbhh,1w k /5nwqy .z.idden, 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 griru/*,qvp,; kq3rbby what interaction could they occur? For those forbidden, exqqbpiu3/ *r,vgkr; r,plain 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 ayli9vb9 fk58bs8 uu0n $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the eletqiu 8gpob ou3e1jsg/5+8uc3 ctroweak 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 the reactions, Eq. id* isu 8yq)0.x2:fekz4nnbh 32-4, for producing a pion. y)*qn0k ne d:.ufxbi4 his28z $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the react n3*mnf lr c b,kts2wh.1q*zb.ion $\pi^- + p \to \Lambda^0 + K^0$ 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:sy bkc0uj2x) 8 7jkug-ro4ik8ebr t8 water molecule?    fermions

  A proton and an antiproton annihilate en3f 8z6vlpb51x bj:vqy1 ww:wach other at rest and produce two pions, w1 :y8bjvx1pwz 3: qnf5vwl b6$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unificap(ru *q frl +giz4oba* /fd;2stion 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 .4vytky 88y.g 9wljb2bzlkd, in Table 32-2 are in terms of proper time, measured in a reference frame where the particle is at rest. If a tau lepton is created with a kinetic energy of 450 Me2l tbzk4yy.wgvljy, 9d8 8bk.V, 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 *4h t0xhzbfy6 particle in the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the reactid7nx207nksh6j - p jwyon $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of lrgx9ji)67t/k1 cjjw kight $c$ is the speed of a 7.0-TeV proton?