Give a reaction between two nucleons, s;;k 4tzpsaw7q imilar to Eq. 32-4, that could produce a wsqt4z7kp ; a;$\pi^0$.

  If a proton is moving at very high speed, so ta *kutnk d.1ow:z4p.what its kinetic energy is much greater*ku ow.wd.n1z:t4pka than its rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," m 7l4umxon 2d 7q3oyz3wade up of the antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of suomd3 nyq7u7x lz2 ow34ch antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the ele i1q ozo.m1dj0/vat 4bctromagnetic interaction?

Does the presence of a neutrino among the decay produp u;p9( -auxtdcts of a particle necessarily mean that the decay occut x uup;dpa9-(rs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interactfd. k )qz,( ryexp,zf dy5;-tmion even though the neutron and one of its decayq(yfz- erx;)dzkmtdy,p.f5 , products (proton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, gravitationa6u+i 0 elpi8ws/q/um.u.za qmq ht, (al) does an electron ta 0/mawt.8a ii/ suz .,qemqp+uhq6(ulke part in? A neutrino? A proton?

Check that charge and baryon number are consp1 ):c qp7mbnzerved in each of the decays in Table 32-2nqz:pc )bpm17.

Which of the particle decays in Table 32-2 occur via the electjs i- s jfx0m* jt2b,obmxc.83romagnetic interaction?scb j.x*xf,3 -t 0ijomsbmj82

Which of the particle decayslf)fh jhfm83b *vv3t3 in Table 32-2 occur by the weak interaction?

By what interaction, and ;lkgsyn,)jn3cz; ;x 1 (czrx2dk8ltb 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 electromagnebl- dwn,) 9ce)kd0qpgtic interact )d -lq 9pkn0egcb,)wdion?

Which of the particle decays in Table 32-4 occur buab,zro uqj3l/1 6:g boyh+.dy 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 jwyokyc1e+lb;)n cr*p-x uj532 5o k jno color charge or electrical charge, and did not feel the weak force. Cou jx ;5jo )k 3wepn1o 2jyl5+yc-bukr*cld you say that this particle even exists?

  Is it possible for a particle to be bota;j7x- 8xn athh
(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 chrom/ 4mrc+,uvc4 snow 6syodynamics, would it be possible to find particles made up of two quarks and no antiquarks? What about two quarks and two antiqua s6vmuw+4r ,o cscyn/4rks?

Why do neutrons decay when they are free but not when they are inside 7v5(h64 :c yci) v jf,bv,eddcsvl3hithe nucleu,54cli cecyf)d7v i(6v bvdjvshh3 ,: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 mu*up 3-jlb : z76;zuw hxeh.8sxc7lvenergy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-qx0oa*pf aryc)39k1fGeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclo r-:vtoli7d y 4gld(j.tron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete *: ow x begho,d0:quy8revolution for a very high-energy proton in the 1.0-km-radius Fermilab accelerator? T oxy* ,h0:eu:dwq8bog =     $ \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 acceleratek+v e7;db 5nqx1xe3ynd $\alpha$ 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 nuvhp 13ug(4mtl 3dh7du cleus: 30-MeV alpha particles or 30-MeV ptm(h4du7u3p 3vhd1 glrotons? 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 o/ 2x.rrvyi/hjv ,ne* of a cyclotron is 55 kV. How many revolutions do protons make to reach a kinjy/.e,v 2*ihn rro xv/etic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength 4du5zxe m0c8jl 01go v($\lambda$, 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 acceleraos 1wweo(;pndn72 o xv9w.cx:te 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 house the magnets fo h4) lzno.hkv(r the Large Hoh4nv.zkl( )hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab -t m,te(k-jb7 soi*:g waxi+eTevatron takes about 20 seconds to bring the energiesbx sji -k-moa:i t +,7eegt*(w 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 essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particle (chargmzc7 t2av 60jz2nb r5vbn5 lw)e $e$) 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 Fera,6by*bet6ypr d6e5)2e*nnuav e ;ic milab synchrotron for 1.0-TeVb eyc eiu2 r6;p6* ,y*bd)n56 netavae protons? B =    T

  How much energy is released in the decaymyjh:1m9mam* :2zdss)yep f n3v 7y3( ttoz (l $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy .3:yiddm;:prk7 db a cis released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neq *e,n/ te*x4ivrj d u dny/m)sim-)o3utron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating iqe vtqwai) 7i;: 4 1clo(vw;gparticle were the kaon instead of the ewowq;(i v :7l4tigi1v)q ;a cpion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. W ;ozvl**ow vl9oxf1)what minimum kinetic energy *owoo) ;l9f*wzv1x lv must 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 ney0 k q3i(gqfvp+v;/ ugutrons each have if they are traveling at the same speed toward each other, collide, and prodpk uyi(v3q+f ;v0ggq /uce 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 o(g.f fg+9urm nf the W and Z particles as abo. gm9ugf (f+nrut 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photons produced when a proton and a -9sd d qj,gw4sia)ij2ntiproton as -a2 di qj,sdwg49)ijt rest 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 and energy, that it is impossible for an :su tut /1pr1m1s 6vmwisolated electron to radiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig.ustrmst vu1 1:w6/1m p Below)?

  What would be the wavelengths of - k.y xx d3d3g+jsujfcff)i, .the two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihilate head .jfkfj i3d dx.),x+-cf 3 yusgon? $\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 possib ha6z7-b7hzisle? For those forbidden, explain what laws are violated. b7 azi-hz6h7s
(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 or (c* ge b1r1jtv.6xzmmuh40two 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 btyfuw+ j*ii77k(ii5a1jf1 q energy 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 thf*,swyk;qlo imfd 7.8 e 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 tu g4r3-l /t dpdqrt3(zhe $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width o u -u :b5:6q htp1npac4)xxrvzf the $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertaiyh*gr py2 hw83nty) 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 b-y hz py7d 09)v8tldfare possible? For those that are forbidden, explain which laws are violateddtyl7zpvy)8f 0 hdb9-.
(a) $\Xi^0 \to \Sigma^+ + \pi^-$
(b) $\Omega^- \to \Sigma^+ + \pi^- + \nu$
(c) $\Sigma^0 \to \Delta^0 + \gamma + \gamma$

What are the quark co lli a aj;99rbjrghhviq 92r:6 hb+2,ambinations that can form (a) a neutron, (b) an antineutron,9lhq;bav,g:rihi6j l 9b2r rj92ah a+ (c) a $\pi^+$, (d) a $K^-$?

What particles do the following quarkix4ha0bjy36q mf)jo 1 combinations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combinatiyz/ z1etm:ul d mqi15:on 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 quaw*hz .;6c hqvco0)emxgd7 q:lrks (as in Fig. Below) for the reaction h d:hc qg0zmv)7x* l;cew.o6q$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the re.n3opfcha7k 20jh(:v /ax ub.pv s,ddaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetu.nshfe 7h7iy aq,7+hic energy is 25 GeV? What is its wavelength? . ns ihu 7+f7h7y,eqah
$\approx$    $ \ \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-kadcvh0 7q1zz 17kzm8mm-radius Fermilab Tevatron 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 1170 m zd8v7azzkchqmto reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when ansac+ly8e4fsc 4pg:me6 ,a e *f electron and a positron annihilate each otherc+y,p8fe:al4eas s efcm6*4 g? $E_{\text{total}}$=    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 followin)a hsdxrz w(s1f(9n7 cqo m--vg reactions are possible, and by what interaction could they occur? For tn(q 1o -a(s sd-9) xrwm7zfchvhose 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 ps8cr .560mm84hz+ bc mhvjq ccossible, and by what interaction could they occur? cmzcm.8h +50cv6s bhc 4jm8qr For those forbidden, 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 shta6;3 w +atq$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak the4tj +6ash3nkwr+r nwy jl 5d);ory 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 pkhnu1l6*c+2)prevh9r .sasl: s) sze roducing a pion. kp26 ur 1srcls*shv.ez 9e)hs+ : )nla$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for2g0 hg/ 6czhwrj y(,wn the 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,.o c)kpxj f7p2 8tcl+ zhc;0 ;urxgux a water molecule?    fermions

  A proton and an antiproe 2i,.n2eevvu3 1n asston annihilate each other at rest and produce two pions, si1, e.n2v3uv e2aes n$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distjj4uw khr9 crq.ixcd -,6u1c-ance 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 Ta7z+0y (-7c)wjh j/mxrxzpnzcble 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 MeV, how long would its track be as measured in the / ch yr+(xzzz7pnc7j wjm0 )-xlab, on average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the followingr r(;n kq 6+r,mvzvuo7 reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model t obpnkf(r(6 0nn8pde*y3im d;o describe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the.6g zmep , hdqz(molu3oky6 43 speed of light $c$ is the speed of a 7.0-TeV proton?