Give a reaction between twxxjarp*wc5 ;0 ,rwd, k/0oacwo nucleons, similar to Eq. 32-4, that could produce a o0 *0,xk/wcawa; jc,5rwxd r p$\pi^0$.

  If a proton is moving at very h0 rues ,te1/vbv/7qlr igh speed, so that its kinetic energy is much greater than itulre1s70 vq/ v be,r/ts rest energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the anw 29fluurm6- (lmsl;c1g vt/wtiparticles to the constituents of normal atoms, consist of? What might happen if antimwv(ft-sc /;u1wm rumll 9l2g6atter, made of such antiatoms, came in contact with our normal world of matter?

What particle in a decay signals the electromagnetg(/gm+fmgv+ i ic interaction?

Does the presence of w.x qum:-s/e8d9dfbce:p6 6xblub: da neutrino among the decay products of a particle necessarily mean that the decay w6f8.ube x:9ebmdxd b 6sq:cpdl:-u/occurs via the weak interaction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays v1g+u t g0)rpfdia the weak interaction even though the neutron and one of its decay products (proton) are stronglg +d01rpf)tguy interacting?

Which of the four interactions (strong, electromagnetic, weak,1(rd1u8nuzmajw/sqd+v f2 w0 d he;1d gravitational) does an electron take part inumdw/d8dznf0r;jd+1 1wvh 2aes u q1(? A neutrino? A proton?

Check that charge and baryon number are conserved in xff5 .0l+,q *y udvzsen4r f5e-ye0vjeach of the decays in Table 32-qxu,s+rez0.dyf f5 5e j v*lfve-y40n2.

Which of the particle decays in Table 32-2 occur via -,bg nw 5 5bm3l.anlmb9a.xs gthe electromagnetic interacm.-w n bmagngs5b l 9x,b3la5.tion?

Which of the particle decays in Table 32-2 occur by th(bomi.t 2d2z szx9an j/*q 1ske weak interaction?

By what interaction,( aa7rb q3v0k ykn7:un 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 dem xl.ov 8n 3e2 35o.okbvfk.vwcays in Table 32-4 occur via the electromagnetic interaction?3f85vbn.km.lx.w3oeo v v 2ko

Which of the particle decays i1-x 1rx(adwoa oxat6:n 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 cd+v d 9crv hmu*al828polor charge or electrical charge, h a+pdv8vd9* c8m2 lruand did not feel the weak force. Could you say that this particle even exists?

  Is it possible for a partd1iu k -ag.; -cbkpv :)qg;jd:gx:kuticle 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, woaschmq 1j (eex. )pnv3tyf60 4uld it be possible to find particles made up of two quarks and no antiquarks? What about two quarks )yf( hp0xs3njta61ev e .4mc qand two antiquarks?

Why do neutrons decay w egpj0g+1t zyp.m (lfzvn*e5w8mu r01hen they are free but not when they are inside the nucleus?z f(0rvl j8.nte50gmp p+* z1g1ewmyu

  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 en*/3bjop.j(l , bmbfniergy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons. r /6jr:vwqi* o E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in7 xlyj k9b7hi0 which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a very high-energy pr i(r;r+bc))sjp)j pdow 7 av5/aodpl5oton in the rdwdrvi5l 7)ap jcbs5o (op))/a+p;j 1.0-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 Eghsrdj - 5e:;uxample 32-2 accelerated $\alpha$ 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 particpmr4hhw(c -0duy4k 9 cles or 30-MeV protons? Compare each of their wavelengths w0-wdkh(ryu9c mhc44 pith 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 rev* u (oqmcuw1l;olutions do protons make o*1qwc;m( ul uto reach a kinetic energy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength* w8l;xt+apzw 8zong w3+ycv8d 5the+ ($\lambda$, 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 deutero; cwey6jn/llp;imzf )2*x 4hyns ($^2\text{H}$, 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 qecu f7phxo 94u0-:0xujh6h a will be used to house the magnets for the Large Hadron Collider (LHC) calls for proton beams ofx0ua:9e4jofu c-0uhhp 7q h6x energy 7.0 TeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 secon65o7jnjx w m,zi ,ayq4ds 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 ainqz,4w,y6x7j 5jom assume that the speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a particle (charge /b5tci() iudle p9e o6$e$) 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 intensit qid*68p7co /vunb- pqy is needed at the 1.0-km-radius Fermilab synchrotron for 1.0-TeV od-*iqvqu 7/nppcb68protons? B =    T

  How much energy is release mvvh.8o:ag/ md in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy z)m1 emfnb-,i is released when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required t7d (*zqkc,j( wxla5slo produce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particlm ;7; r)e2he kknblcee*.lr4re were the kaon instead of the pio *4ekc; re.72 lhnb)rree; klmn. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward h:rfpxq 8-icp).7jcpeach other with equal speeds. What minimum kinetic energy musf p87cq xc.-ipj h:)prt each have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must twog5t in t dq5iz.g6pl*3 o7*nsh neutrons each have if they are traveling at the same speed toward each other, collide, and produce a nd 56thgn zipo.it7q l*g53s *$\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using Eq. 32-3, given the massei2 lrnkm7d1bz5 v,2sg s of the W and Z particles as about 8sgm 7kz2d il5b1,nr2v 0 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 *s1o0aqe9 p8 fe;j g3eo pxy4cantiprotonfo3ca10y e9 ejq;o *x4gpps8e at 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 iq+u ofj,:gakz g e:(d3solated electron to radiate only a single photon. (bague, +:zqdo 3jkg(: f) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of the twosd z 09fny3m9j photons produced when an electron and a positron, 039mfy jszn d9each 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 possible? For those forqfqhy ;xl3q v2 bc ,:r76wbaq;bidden, ex2bbl7q6,;c x3f q qyvwar;:qhplain what 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 each of the two product;adba k.9a( 7ttlc(vas 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 m f1xvxac5 b7g(e:wl, 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 thlgpgg*9e moa jgcd 4g3z v7vwh))(w 3*en the lifetime of the $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of twgd, ybh3 .dk7he $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of to4m(31 ,gcgfntg . nis 4ibfq:-e6g qbhe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainthzd-kd( bao t v5ff8+;y) 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 mspce/*vp. (ethose that are forbidden, explainpsepv/*. mec( 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 neutron, (5 aahokdyky0m26 .6zeb) an antineutron, (c)2m6k6.5kye 0 zhd aoya a $\pi^+$, (d) a $K^-$?

What particles do the following quark combi+ fxg,v4/:qc xbisj:nnations 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 produce z) 2 8gaujewb.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 reactiw*a h6fg 4 --jrjn,lseonsn,wa- -e lrhgjj*46f $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the reac.ol:k vxqa(ki*j-0zbtion $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a protoelfs if3(pt8 2n whose kinetic energy is 25 GeV? What is its wavelengt(p8 f3 sftl2ieh?
$\approx$    $ \ \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 Fermilwzqo 8b. -2ileab 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 lo8i- lqe.2ozbw ng 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 posw1m* g+(/b iaq7)ot+ -n tn+mqynyowhitron annihilate each otherb71(t-maqm + h* g+ny)/ +nonw yqwito? $E_{\text{total}}$=    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()btpqkw- *v ayth k28 possible, and by what interaction could they occur? For those forbidden, expykq)kvp ( 2t*bawth-8lain 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 arer/xfxd -b8crn/9hwa8 possible, and by what interaction could they occur? For those fb/ha nfwxr/8 9-crdx 8orbidden, 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 agb+b6f0ph t sn:8by/6fqxs m 4 $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak thex-z wum,-;ai axus )q3ory 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, d2wmusnx6 8m2 for producing a pion.26mx 8n2mwdus $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for 4n;8us n b/e+bnezf;athe 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 a watern6a0g,dpvygw )o3f m 1 molecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two lj,g.3 +ti+pdse7r fw pions, +rig f,d3l+tje.p7w s$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unification distance w fe/8ygj w/)/zveh3m 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 on (0r9 ysr16h rzy oni;*ps:dpf 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 wou*ipy;6r0:dz sh(9ns p1 oryrn ld 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 follfyo;hh7mhbe1ll;:rp zh3.ec841 xs f owing reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to des8sa 0r/x *rkgccribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the sc4hwmlc8km2ai* ub,.ew im* 1peed of light $c$ is the speed of a 7.0-TeV proton?