Give a reaction between two nucleons, simis.ip7wynj5y 6;k z,k plar to Eq. 32-4, that could produce a sz;w5yy,i6kn k.p p 7j$\pi^0$.

  If a proton is moving at very g h6l,ripdd2lje( m pk250b+m high speed, so that its kinetic energy is much greater than its rest e(ig5lm bd e2 ,ljhd0 2ppm+k6rnergy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticles to the constituents oxj pq2nd +pv);f normal atoms, consist jq); x p+pvnd2of? What might happen if antimatter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetic interadt7n*a)fbc:-w27)fjz as . cv oz.odlction?

Does the presence of a neutrino among the decay pr + k2o- d2w(cnne-vdkqoducts of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via tqnwdo kdev2 c +2k-(n-he weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction even though the neutrons3zc( 8t x,cgb and one of its decay products (prot,cg(x8cb zst3on) are strongly interacting?

Which of the four interao d-*q fnkw51xqh1oox*wv38i ctions (strong, electromagnetic, weak, gravitational) does an electrkxxv 1 *wh3iqofoo1qn *w-d58on take part in? A neutrino? A proton?

Check that charge and baryon number2 7rqwyd9e9 xx are conserved in each of the decays in Table 32-2w27x 9xdqe 9ry.

Which of the particle decays in Table 32-2 occur k k-7ity98 hw 5lf7b7 t6bnlmwrxv-y7via the electromagnetic interactio kwhn7ky7bxw7m6t5-9r -tb7y8fvl li n?

Which of the particle decays in Table 32-2 occur by 0gqwwq b1:3-.co9xcmgd: z bo the weak interaction?

By what interaction, and why, does9trnjyu,s: 0p;/b(rkdqq6 b sjy .0cp $\Sigma^0$ 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 ektm .yk,7w jd8*2c vp *4xjzm32-4 occur via the electromagnetic interactionz **8. pcjy4d2jmk,mx 7 vektw?

Which of the particle decays in Table 32-4 occur by the weak interachg + x(rj0 ,xsrraia8)tion?

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 w(64qa z;vwvq4 3efpd yas massless, had no color charge or elec4dq wv4y v(;paez 3q6ftrical charge, and did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a par(5jnvvq:11 v; txtffdeb:e wrm7qu ;iy- z 3x5ticle 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 chromod9o+hm5tsxpfb18cz : -v0g q;od1 af jdynamics, would it be possible to find particles made up of two quarks and no antiquarks? What about twoz 9a op+:01oxvcd81bmdq5htj sff-g ; quarks and two antiquarks?

Why do neutrons decay when they are r4ce0ck/ i 34otl)m o86nbuugxd )d5f free but not when they are inside the nucleus?0or bodl4iue6f m)58ndx 3gtu4)c/ kc

  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 elk7ee) +81fnzh klzf.3 drh4gnergy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeVi+num8 +nt pg2u4dg u5 electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cycroy 5tk9gwz ffy:5f74lotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a s) ftez o/l1f(very high-energy proton in the 1.0-km-radius Fermilab accelerator? T = lzt(e s)1/fof    $ \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 accelerated pqpin o) -zsr82gjo 3llj o9oje:/39f$\alpha$ 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: 30-MeV alpha p rm;ox6+po2jg articles or 30-MeV proto;gr26x pm+oj ons? 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 cyclotron is 55 kV. How many revolutiokkfe9 ybc2 u/u634iqcfy yg3;ns do protons make to reach a kinetic energ ycik 3bkyq/ gf;ceu2uf69 y34y of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength nxd q.fag.+/.; uk mea($\lambda$, 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 accelvdk.cvs b: ,z2h 8gbz8erate 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 wiwb *9:wrudx:ell be used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field ebuw rxd*w::9will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds fc5f;v s-v vm8x lor94to 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 xs9mcr o-f4lv 8v5v;f the speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of e/m1cb/ :qt rdjo i0yi83+akl 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. ;vfgjm gt)rs+a+v.e*0-km-radius Fermilab synchrotron for 1.0-TeV +tvg + g )*mej;.fvrasprotons? B =    T

  How much energy is released in the debt bc3jv)ue 9+cay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is rb- eg mtyz/1ktpxx.+ 6eleased when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-ant/v9f c pz0v/snineutron pair?    MeV

  Estimate the range of the strong force if the mediating particle wcc c u iwi/+o.-u70r1w:z-bjf *c udhjere the kaon instead of the pion1uri-b u.w u+w:dcz *7c-0jofj cchi /. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward eachd w+1vjf)tu; a other with equal speeds. What minimum kinetic energy );ua jvw1+ dtfmust 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 iwi ycbd8+m7*have if they are traveling at the same speed toward each other, collide, and p*m ydi wic+b87roduce 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 t1q6bf e kj(9,q.*xbu -xfydqkhe W and Z particles as about 80 tyx,-ufkqjbx.1 b (k9qde 6q f*o $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produce)c 6-ac+ *txvnyc2u f-eoxlh-d when a proton and antiproton at rest annihi2-vxc-ct6 ehyfnx*)a+-o cullate? $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 energyuyb +x-5)oc 4s z5.ja +nxtjlh( l.tvr, that it is impossible for an isolated electron to radiate only a single p(tl+sh4xzrt. c uy5-5n+vo jblx a).j hoton. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wave pk-n)w0eaneh-cw1;kf3k 2h ulengths of the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, wch )0 e3nn1kfk2ae-wk h-; upannihilate 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 de:5 c*5y.mzre4jvtz hb cays are possible? For those forbidden, explain what laws are violated.zh:jr 55 *ctzm 4yebv.
(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 energyrc qphc v7jkw1sug.z+6c7d. 9-wnk, 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 electro0l:wut sr:(qhn 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 wio8mc3 ncdy q jl( w9c08i23hc*dfo n)vdth 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 of2*gpt7x2 /vz(o - um 3zs( mfv4kybmh pa4ki*q the $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width ofnfnq d:c z.ca9i14j1k the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertah s6jd/( aapi7inty) 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 ar8 ;1g8q psnrd0qndli4p(ygc0 e forbidden, explain which laws are violated.g0l;8s0n(g 8dd4ny irqc qp1p
(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 nerf /gg(8ad :2bucrkrr5 3;blu utron, (b) an antineutron, (c) akar 3r(d8 gf 2u clr5;:rg/bbu $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations pr;fr-2 :ffhmk aoduce: (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 .)gotndg 4 u;dproduce 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. Below) for the reacti. 7yp.znuw)e(dy uoo*on u.)dz*ep(y7o ywn .uo $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the r(jnzga2 mb md)pvz:8,z /bgp3 eaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a wtj5e/xj /7g s )gf,huproton whose kinetic energy is 25 GeV? What is its wavelj/gtg e/5s7x fw,j)huength?
$\approx$    $ \ \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 Tevatrflkdia. ra(eu*w+. 4d on with an energy of 150 GeV. If thea l.ird.wud a+4k*(efy are accelerated 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 ann /s bcd09ripm4ihilate each otherscpmidr b /940? $E_{\text{total}}$=    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 followin4uoys7u,hn )zn 6k 7jag reactions are possible, and by what interaction could they occur? For thos)6y7ua7os,k z nju4nh e 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 possibleyewmw *2 az mdb/;hvw: rm9n2*, and by what interaction could they occur? For those forbidden, explai2 wmdembnw **2;h/r :zwvaym9 n 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 aqja.yej /6hf: p; 9pucry;ms ; $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak tzz :qpp*v(6pr heory 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. 32-4, for producing /m*0xnhz4/m4wf rrwoglpt;+ *kt , yba pion. rm/*0w4tl4 m y;n *kgprx,+b /wothzf$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for cqu: r+ irk*ure,znd1i1dj4,p *ms +pthe 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 in ql()u6s apfqqy 8;j/y:tix5e a water molecule?    fermions

  A proton and an antiproton annihilate each oth;hc xf5yppu+5 er at rest and produce two pions, p;+5 ucp5hxfy$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification * cuswq f/7; b.4hcdyvdistance 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*r3l e4u w*vzib,rkufjx*:5z in terms of proper time, measured in a reference frakr*xb4ruul:* wjezzf i5 v,3*me where the particle 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 ymvj8m)i 2 fu t-0cin/nsebl/r(7 1gzc0i u7tin the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the reaction m :56ij- hdh4klbnknr ou ;b06$p + n \to \pi^+ + \pi^-$.

What fraction of the3t iglen):mj * speed of light $c$ is the speed of a 7.0-TeV proton?