Give a reaction between two nucleons, similar to Evoay* / tpj)/e/uyv,kq. 32-4, that could produce a vyta*jk,)up o//e/y v $\pi^0$.

  If a proton is moving at very high speed, so that its kinetic ennhg . rp2mi1z -.ixqi); ;dcurergy is much greater than its re;;phg i..xc)inqr 1r2ud-miz st energy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antipa gadha9 + ,(qjg vmsix7pb+6(zrticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with our normamg+ 7h(9(dbsz+jqg v,xap 6ial world of matter?

What particle in a decay sighcp2pud3 o(1 i7 v ezyizrbd71iu2*7bnals the electromagnetic interaction?

Does the presence of a neutrino among the decay products of a particle necessarif.w qw6df.y7 zt(6hstly mean that the decay occurs via the weak interaction? Do all decays via the weak interaction produce h q.sftdy7fz(.ww6 t6 a neutrino? Explain.

Why is it that a neutron decays via the weak interaction even though the neutro5/v;s jk1ps.*h6kp d pekoth044 xa fdn and one of its decay products (pkp/hf4tkde p0o1 ;5vshp*s4kjdx6 a . roton) are strongly interacting?

Which of the four interactions (strong, electromagnetic, weak, gravitational)aist bx1 0cw--v b;q,;bip -zb does an eli 0x1t-pq--zbc vs;baiwb; b, ectron take part in? A neutrino? A proton?

Check that charge and baryon number are conserved in eanog 9 +t1hxnu:nh4hsc2,)w qrch of the decays in Table 32- wt+:,12 h9cnn4hrqn)sgoh ux 2.

Which of the particle decaa). .dkfk6ckknqnoh+1hcu vn60 o9 8pys in Table 32-2 occur via the electromagnetic interactio6 a n v)kq1chknfn +06 pu98o.hkk.odcn?

Which of the particle decays in Table 32-2 occur by tb26n fxx)yepru0/0u p he weak interaction?

By what interaction, and why, dqhosbmh25 54 eoes $\Sigma^0$ 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,tswz +vzvz/1o,gb2+ fo7 ed p occur via the electromagnetic interactioeo,b1d, fg2stvzz z7/wp +o+vn?

Which of the particle decays in Table 32-4 occ2qdnjim,i6l(.g k 9yuur 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"sfr* on/c o fkr:,+6*tjvvce, that was massless, had no color charge or electrical charge, and did not feel thrcrf,6tj,/k:fs nv*c e* vo+oe weak force. Could you say that this particle even exists?

  Is it possible for a pahtkkrsj )x83 3rticle 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 be possible to find partiw 8wf/qdabs08-nsty r;ysh45cles made up of two quarks and no answbh-5t qarnd4f8 / sy0ys;8wtiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are frbh5 dlhu 8sfi(2hh 3;d. 4d;zxk sp9xeee but not when they are inside the nucleus?.xh3uesbhzs8pd 4h2h5x i;d f l(;9kd

  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 8 itu sg,0v8ktenergy is 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons. E qr(3dmy4j qs:a -t2bbmutf h v 0)js3*=    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cycgii cia xn9k0kq )k++7lotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for o5rc ptx9/ln59)zj nk cne complete revolution for a very high-energy proton in the 1.t czx5p n9cjl/)knr5 90-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 offp zou3* r6lj2 Example 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 picki sog,px: 7 wnrev;a xuh/u/n-2ng out details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of their wavelengths with the size of a nucleon iae;/7- /goxnx:p ,n us2r vhwun a nucleus.  ----待选择---- alpha particles protons 

  The voltage across the dees of a cyclotrohd sr7aa4xzq+,8kq t/x*m z u7n is 55 kV. How many revolutions do protons make to reach a kinetic energy of 25 MeVxuazqm qx hrat8s+* zd4, /7k7? $\approx $    $\ \text{revolutions}$

  What is the wavelength a3n9,y58 b u igpa0fm)vdu0ms ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radiu y1si5cn,t:gg s of 1.0 m is 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 hos2+ x0j9p 4)d gvroximuse the magnets for the Large Hadro2)voxi9 4rm 0jspd+xgn 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 Tevatron.swoe .dm 5w6h takes 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 energyms6de.w 5o .hw 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 (crs.*kzgmu-- f4*m wb pharge $e$) 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 intebm/9+y y7z gsensity is needed at the 1.0-km-radius Fermilab synchrotron for 1.0-TeV protons? Bzysge 7y+m 9b/ =    T

  How much energy is released in the decayz3(jcji1qk/ +dr . vel $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is rel*hsebj5th p2v :wc5d4 eased when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-anta(tr+6v; nfuu ineutron pair?    MeV

  Estimate the range of the strong force if the mediaticeyt s1-h 4lb jttr7:/ng particle were the kaon instead of tyc7e4:t1b s jrh l-tt/he pion. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other with equal s 4y1sorb4 g3bvpeeds. What minimum kinetic energy must each3o4vy41 r bsgb have if a $\pi^0$ meson is to be created in the process? (See Table 32-2.)    MeV

  What minimum kinetic energy must two n0hm v6dg n;q,uk(4urxeutrons each have if they are traveling at the same speed tow ,x0mvurdgqu(hk6;n4ard each other, collide, and produce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the zd.e,nm1 s uo j44se,v.s2pjg weak force using Eq. 32-3, given the masses of the W a1o d4ezu,sps.v2s g n4jm. je,nd Z particles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of the twohjsw *io rc)v7 -t 6hxn-e)uj9 photons produced when a proton and antiproton at rest annihilate? isn7j* o vcuhjhr6x e-t )9w)- $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 i xy*/l)m gnv/,8/vbaw zzw c+tt is impossible for an isolated electron to radiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram i/,) m 8/b/y xvlc+g*za wtnvwzn (Fig. Below)?

  What would be the wavelengths of the two photow,mxziz2 0f1 rns produced when an electron and a posit0fwz2xr ,1 zmiron, each 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 d)w36vjjf3( o ouu o3qvecays are possible? For those forbidden, explain whafovu 33 o3j )ov6(qjwut 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 enerl/lrh /ao-z)wme d *g7gy 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 e ,41-as4fqq4ed,rymuxvjc * 7uo.cor lectron 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 then the lifetime of th1;4d/kvgn chj5 u.:g, fl;fqvvfl0 sne $\Delta$ resonance using the uncertainty principle.
$\Delta E$ =    MeV
$\Delta t$=    $ \times 10^{-24}\ \text{s}$

  The measured width of the ,:v/ilmgr guk. ,c/bm$\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of the z5kxfb77 h,vh$J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncertainty) e46uh) paeu62kprdy* 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 are forbidden, explas a)-v:z7wk-zn4gh o min which laws are vi- a g-h7komvn4z )wsz:olated.
(a) $\Xi^0 \to \Sigma^+ + \pi^-$
(b) $\Omega^- \to \Sigma^+ + \pi^- + \nu$
(c) $\Sigma^0 \to \Delta^0 + \gamma + \gamma$

What are the quark combinxkfy -ci02 sj:ations that can form (a) a neutron, (b) an antineutron, (:0s2f j-yxcki c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinatjk8l3a6g phkeyl 1, b3ions produce: (a) $uud$, (b) $uu\bar{d}$, (c) $u\bar{s}$, (d) $\bar{d}u$, (e) $c\bar{s}$?

What is the quark combi 8ri/c1gc:cz u2 u( gz+nl amc6ib9/btnation 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. Below) for /et:mk-7: zxkxiusu92mlk1 h the reactionsu/mk:telh 7912xm-xz uk: ki $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for th3 )lggyk 3paf9b) rr)f3t/u(jrw k0vhe reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? Whar nynv-3/n qb5c;mrv4t is its wavelength? q cv5nm-3 rny;n/r4vb
$\approx$    $ \ \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 Tei(3 f0xcu hjb(vatron with an energy of 150 G uxj icbh(0f3(eV. 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 reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is released when an electron and a positron annihilat8 i6lsa(oce-4 m0oz gye each othe-e am(gy04clzo6oi 8sr? $E_{\text{total}}$=    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 what in43h ts3f8y pxjteraction could they occur? For those forbidden, explain why. t8jph yx 4f3s3
(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 interaction 9 r(hq5p pxw,rcould they occur? For those forbidde(,whpr x9rqp 5n, 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 gg)m0x56 kt 2 ak5wmts s+kt9t$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in4 . t2uyvvbjs8rqiw;axu(4r,t(9aq a 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. 32-4, for producing a pion.:z a(,p3nppgr 3(ngzp ar,: pp$Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reactif)q8;p crnq1zcez ra53z+: lr on $\pi^- + p \to \Lambda^0 + K^0$ 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 therpq:jtyd1fs 3/q0t iom2 )8t0 lpva:2 /yrfyjme in a water molecule?    fermions

  A proton and an antiproton annihilate each other at rest andr1chjuv4 q-x ( produce two pions, vrx1c 4-qjh(u$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-c. ay2x* fe0wfe*jivy4er5kz, alled unification 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 in Table 32-2 are in terms of proper time, measured inez4 lc*f,ju6uv,hg.h h mg +9d 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 lab, on average, ignoring any collisi hu9ue 4g.*fhh, vjm+cl,gzd 6ons? $\Delta x_{\text{lab}} = $    $ \times 10^{-5}\ \text{m}$

Identify the missing particle in g(;dfyim s+x-q:ja1m8qi:6m n1hpvi the following reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to descr9o(ffpu nhq77feqh0 0ibe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of light 0q 9a(px7fnnq$c$ is the speed of a 7.0-TeV proton?