Give a reaction between two nucp2f3 taag fd:h i;:j/eleons, similar to Eq. 32-4, that could produce a fg a hip edtj/a2f::;3$\pi^0$.

  If a proton is moving at v pxm2l56imwk7l+1vc l ery high speed, so that its kinetic energy is much greac5lmpx l 1v6+ml7 2kwiter than its rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up ofdo/ol0 mg j(e3 the antiparticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiato/3ojegom l( 0dms, came in contact with our normal world of matter?

What particle in a decay signals t, /uf y(gt.u13tumhwfhe electromagnetic interaction?

Does the presence of a neutrino amoh 9q.gm7kq6 opng the decay products of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays via t g.76qpom 9qhkhe weak interaction produce a neutrino? Explain.

Why is it that a neutron d:23ec pemdu2-,bk q3 8xzm woeecays via the weak interaction even though the neutron and one of its decay proe 3q:82 3u-mepz becw2 dxmk,oducts (proton) are strongly interacting?

Which of the four interactions (strong, el+tci.o,f,yc ;c . cjirectromagnetic, weak, gravitational) does an electron take part in? A neutrino? A pyrci;,c.o+ij ct, . cfroton?

Check that charge and baryon number are conserved in eachd-deni-l,pb2 ;htrls:. - ecl of the decays in Table 32 d-t.lhn,ibd2 -e cl: ;srlep--2.

Which of the particle decays in Table 32-2 occur via the electromagnetic intern- ms 9ut7ahrn at86g*acaumn t7*s gna rh89-6ttion?

Which of the particle decays in Table 32-2 occur by the weak interactiofi, cm,5)h s .:jdzm nqzqcowwp. (1c9n?

By what interaction, and why, dov3q dsoa t+cxm :p;p(/es $\Sigma^0$ 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 electromagnetio( - dq .c7mk2mzzssk4)2blpvc interaction2c7klmmz2b 4qvspok.s( -) d z?

Which of the particle decays in Table 32-4 occur bjqi4 n*lxybqosstgvj2 : u33g2*k:-l y 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 "neutr *+w;n6kbqce11v - lzllnp5y ldz1o(/ cpjf/x inolet" that was massless, had no color charge or electrical charge, and did not feel the weak force. Could you say that this particle even exists?fc /eonz k+pb z6( l1lvy-w *nldjp;xq/15 1cl

  Is it possible for a particyt* jbqsc-cofk7(( dk -i8d f-le 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 ben6h4ji7rfn m7iamt 13 possible to find particles made up of two quarks and no antiquarks? What about two quarks an61i3a7 mh7fmntr4in jd two antiquarks?

Why do neutrons decay when they are free but not when they are insidp -:3-g;craewfue;wu e the nucleus? wruaw;c3e;eu-:-g f p

  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 ener:t c2r:0f:ofc w3b;i okhlh8ngy is 6.35 GeV?    GeV

  Calculate the wavelengv *fn,80v;mwcdji, pcth of 35-GeV electrons. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in aiijmzh(y5ck.p9 f+8h cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revol qhm(v joxmaze)a4z3* 9(wqf; ution for a very high-energy proton in the 1.0-km-radius Fermilab accelerator? T = wa(oeazqx3*9fhmm(v )4q zj ;    $ \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 accelj*y6*1 )6rr4 pdeseen/tcpokerated $\alpha$ 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 nuclepl2ej5r qi1xa-xo4cp-,(ahbg 6l g)eus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleon in a nuhl c,xage4 la 51 (ijpg--e 2bp6rxq)ocleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotron is 55 kV. How many revolu316ryv8 (moh1reudfzp x ,rz9 tions do protons make to reach a kinetic enerp1f9(m xrzyz3,ve1hr o 8ur 6dgy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength 2v +wo0s p 8wa,qx rr+u apjyor1z:)x+tb*3zr($\lambda$, 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 accur9ge gb eas,;gnu 3 x.rjk(;/qvu3+s elerate 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 tunne:lgab; ivhyb5om-1d +l that will be used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 TeV. Whavy; :gim1bob-a dl5h +t magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron t/98ulhlv-we v akes 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 protons on each turn. (You can assume that the speed of the prlue-v 8lw /9vhotons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy1r j l empj(7b+rh1 2-cx l:jetj52jdj of 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 1.0-km-ra zcry u94bczjknp z,+48d27g+czm mq8dius Fermilab synchrotron for 1.0-TeV prozj8k zdbgc4uzn m2y8cr q,47 +z+p9 cmtons? B =    T

  How much energy is released in the i6 y(s-b 3pnandecay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy coy0iln wbn6z)9p bss/1 .s)r is released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutr -bcl*ii9ys r9:agk bdnch01j.u 25pion pair?    MeV

  Estimate the range of the strong force if the mediating particle were the kaon )zfnapyxf ) i.+;guj nu3a(. finstead of the pg)3nfup; xa.(uy)f.iz n aj+fion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal speeds. What minimum kineti-xetl1m.hv x+j b4xk0c energy401tjlx-kxxm h+e .bv must each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy musu1.g)ztmr7ig6 l4ud zro lc ty(w.5e,t two neutrons each have if they are traveling at the same speed towa5lgo z.4tt6iwr 1(mugulz. ,er cy) d7rd 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 masses ofsrwu w.oe(03py7 zz19*oni qh the W and Z partic(zpr*u7qz h9w.0in owosey13les as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the two photoit ryskgn5;78fwv a+ 0ns produced when a proton and antiproton vsnwy0 t+fkig78 ;r 5aat 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 energc3u: e3rtav/8 ywyct ,y, that it is impossible for an isolated electron to radiate only a single8 3y/cu t aycv3e,:trw 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 two photons produdw k9w kc/wl bd8;o. rpa44i)iced when an electron and a positron, each with 420 keV of kinetic energy, annihilate head on? 4id.8/l)wdapco 9w ;kkbriw4 $\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 possible? For those forbidd (+sq mgyz21haofg(/qen, explain yo(gq+ (2fmzq gh /sa1what 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 +ojeiwc)yu3+lbl; n v/v9+r keach 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 : gf/-ib+( mwb9xk wghin 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 xrn3 g fgd+j tb;,ro89the 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 the wxssdqi;x2q(5 pt b -ov- 4p*v$\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of th5a,p1w yf oqjw k5 h,6sxo0k +,bnpel)e $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) -kotc /w n(on i-nmovv7))*yd z* ib/vof
(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 possit2 ;j)x6mmu+t-uln jnble? For those that are forbidden, explaijxm) tn ml;tj6uu n2+-n which 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 combinations that can form (a) a neut4 sa+/rb lx0br fmeobi3+0m .rron, (b) an antineutron, (cbl+oem+r3.b40ra xri s bmf 0/) a $\pi^+$, (d) a $K^-$?

What particles do the follo:s-tpc k;x g;dpvj6l,wing quark combinations produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combinatxda: .j6vy+j qion 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. Belowu lc q41r vu(-dw;tt14 fyjo.+cayy;m) for the reaction ; la. tyc(u1;f +omyw -jut41r4dqycv $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram f6hx4bb6efr* 6juws;*yl i ovf j.n0c4or the reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy o m b2cwge2wx82f a proton whose kinetic energy is 25 GeV? What is its wavelength? w8g xce2 b2w2m
$\approx$    $ \ \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-u j i2kzn,o7:;quo0cat -u9 umkm-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 u9ouu oin, z: tuq;2km0a7j- cto reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a positron annihil)ok gb4 d:m,:n5c d 4wfvz(jk(ev8nheate each othe4 5v8w)hn 4v:ekg djk,n e bfz:(ocmd(r? $E_{\text{total}}$=    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, andal2a /c2wt pft:h)4i k by what interaction could they occti2)wl/ 4 tf :ck2ahpaur? 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 iordj)nkh0t . tp .)l3hnteraction could they occur? For those flokrd.h30ptnjt .)h)orbidden, 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 yu7*khjm8 w8d $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs it9j ga-*wrltq0b*p;tb5mu /fn the 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 the reactions, Eq.m r b+5cyrubyctd/-qa ns-:7* 32-4, for producing a pion. s* y urncmc tab7-/qy+b:r-d5 $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the react0immvrqzx2bh 3,a geta+,80bion $\pi^- + p \to \Lambda^0 + K^0$ 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 p4jv4t8 y -fcr9j:nj 3im.icwin a water molecule?    fermions

  A proton and an antiproton annihilate each other at re1 c 0o23xjhamvst and produce two pions, a201 vc3om hjx$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification dismgnx /7a 1h.am mj17aetance 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 termllf :/:v*7qtewmh)az s 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 measure:*emh af)z l7:tv/ qwld in the lab, on average, ignoring any collisions? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in the fol 1j+fp *bj c4)l7csvaslowing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describevjir ph64slgb0s)3z3(k m4eyj 1 oo2/cae o-g the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the spef0sk0 *i8l /o vffrck.ed of light $c$ is the speed of a 7.0-TeV proton?