Give a reaction between two nucleons, similar to Eq. 32-4, ) cb78or va;suthat could produce a ou ;c 87sbrv)a$\pi^0$.

  If a proton is moving at very high speed, so that its kineti6h43zm e y7l5ff7mmjhc energy is much greater than its rest enery73f e5lfmjh67mzm 4hgy ($mc^2$), can it then decay via $p \to n + \pi^+$?  ----待选择----yesno 

What would an "antiatom," made up of the antiparticles to vf7hu;9hdmy c6,mc: r the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in ;:m uhydc 9h7fr,6cvm contact with our normal world of matter?

What particle in a decajgsn49uy -ml,g.ex;e y signals the electromagnetic interaction?

Does the presence of a neutrino among the de80rq l; svxe.ncay products of a particle necessarily mean that the decay occurs via the weak intl8xn0;re .vs qeraction? Do all decays via the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction eveniyk ))elw2;mdegf 5.z though the neutron and one of its decay products (proton) are strongly interlm.wgey k ;fd)zi )2e5acting?

Which of the four interact)gl g j2ww6i.epy fo36ions (strong, electromagnetic, weak, gravitational) does an electrolpyf6ggew w.io6 )23j n take part in? A neutrino? A proton?

Check that charge and baryon number are conserved in each ggxi: purv j0 wku1,blyt-i89xx,6 -hof the decays in Table 3 uh- r0 xb jg1,:t,luvy9ixg8wkpx6-i2-2.

Which of the particle decays in Table 32-2 occur via the electromagnetic int,) d4.fvuypy,2 e bfuderaction.2yddb4pye,u f ,vf)u?

Which of the particle decays in Tabg;fo, b ,x*5ha19xubb zj+xqk4xin m)le 32-2 occur by the weak interaction?

By what interaction, and why, doeqm) *l l2tubaj 43x4mri/z ij6s $\Sigma^0$ 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 ele;h5lrnc; fhi7 3wnh, u pnt-w+0qb3rectromagnetic interactih-;tr h0fihrw,537ln; n3 wq+ u pbnceon?

Which of the particle decays in Table 32-4 occur by the weak interacqoevry (euajq(u,f5jypwp2.zl.e. c 8f* :0ction?

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 masslesg vfp :8yd*:rnwy8p6o8 . awbkzskl30*jc sa7s, had no color charge or electrical charge, and did not feel the weak force. Could you say twp.adz:nfak rk8 *y:py6s*830v7c lwbog sj8 hat this particle even exists?

  Is it possible for a -eic (upn 4bm;particle 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 chromod1uo/h rnwi * -g:mga5zynamics, would it be possible to find particles made up of two1h5r-zaimn *gow:u/ g quarks and no antiquarks? What about two quarks and two antiquarks?

Why do neutrons decay when they are free but not when th1tx+k1dy 9y hoey are inside the nucleus?dy1oyxhkt 9+ 1

  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 energy ih(/df zl e5r4bq72hgtd r m1z5s 6.35 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons kqnca qub5dn*:bn v .se e3l6/.rk0m,. E =    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in a cyclotron in which pro ej8(h8 rtybb;tons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution for a8-w5pa .xkg,uet4u1n/ md xif very high-energy proton in the 1.g/k ,1 x-5ufxptui8 aedmn4 w.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 Example1vtqk),p:*1he de umr 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 pickingh.ckk w) u 4yez-w4e .taai3;e out details of the nucleus: 30-MeV alpha particles or 30-MeV protons? Compare each of theici kaue) hwt- eaykwz3e44 ;..r 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 revonswqu dao k 7)6+xx6v0h8*3k +nf2sukpsjr-f lutions do protons make to reach a kinetic energyws+3*x djq nk k62aohufp0 fk- u)ssv8+7rx6 n of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength (yqj r(af(4e(g ce d88c$\lambda$, 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 accf(7+3m b pabobelerate 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 tg)2pbb 2h9kcyo house the magnets for the Large Hadron C9y2p2cbgh b)kollider (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 takes about 20 seconds to bring th;)k oarmqj+kv +3t4cf e 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 assuco4v q t)kr+j 3kfma+;me that the speed of the protons is essentially $c$ the whole time.) Energy/revolution =    MeV/rev

Show that the energy of a pg9g()bz66gg2*dj mac4 kgptj article (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 1.0-4/e sp3md /pjixaz;1wkm-radius Fermilab synchrotro p; /piea/w 3jxmsd4z1n for 1.0-TeV protons? B =    T

  How much energy is released in tmzgk;ty(*2wh s)ff 0, rx/dvt he decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is released wfae:z:(z w.luu ,z0od hen a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is required to produce a neutron-antineutron pair? mbo -,si.12h 0shta*sycy*pc    MeV

  Estimate the range of the strong force if the mediating paez-kze-mn*xb ,q+kx b ,p)ew* rticle were the kaon instead of the pix zpxqbbe)*m -*n ,k+ ewz,-ekon. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each other er4 k+,j2wclm,pm4oct-m-nw with equal speeds. What minimum kinetic en+,4tj- ,monc-rm2mlw4k cp weergy 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 neutrons each have if they are tra.zwxf 3)/z,x jd: djdyveling at the same speed toward each other, collide, and produce ax:jzdd. f, )zxwd3y j/ $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak f. m atp; tf1b8)w.kxh1f3hkvcorce using Eq. 32-3, given the masses of the W and Z particles as 13x1 vf ;hkfhkb.tp)t awm .8cabout 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the waveleng4lz/eww3ps r* ths of the two photons produced when a proton and antiproton at rest annihilat/s4wz3ep l* rwe? $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 impossms 8nzq8tr6.mible for an isolated electron to rt8mr 8m.s6 qznadiate only a single photon. (b) With this result in mind, how can you defend the photon exchange diagram in (Fig. Below)?

  What would be the wavelengths of t; ,byrblmg9g. he two photons produced when an electron and a positron, each with 420 keV of kinetic energy, annihilate head on?g;,.mryg lb9b $\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 x1jwz*.a ,tpgh 2szn.6pc8uz possible? For those forbidden, exupjznh s1. w p62c,* z8azt.gxplain 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 productsp nbr(w; zrh;6)eqye4 e5,sb v 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 in the8yfmk0 6d4 hf-.ucvox4m .m gs 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 :9ct 3nprpj( wagq+nzw/*c e/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 theu:dati.(s 0mv cv/yn + $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of n apj j0gj6qkcmix1l9iq* kh*(yca+,7z,a8ithe $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy wid49r l*2sf ee0/hnxnu3*fmvmg th (or uncertainty) 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 forbidden6v)ur.7od j nh, explain which lawshrdjn.u76o ) v 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 bm.wvr baur fz yv8q+((:py )/72db pmform (a) a neutron, (b) an antineutron, ((2:.(7pabw uvrmby+ d b/rqmzy )p8fvc) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations produce ;.6g9zjw v,gph itp, (.wolfn: (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 pgt1fj xtq1c /;roduce 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 the7z k wtt38)l qgq b)9x)lfmgw) reaction l mgb)tzl73t qkx g)w)f9 )wq8$p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the i;6dldavgr . wfxnh1(l(; xq/5(evd f reaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is6od ;uhr04 v/bsdekv7-kr1hb 25 GeV? What is its w6 7h o1 k be/vhbrk-vddru;s04avelength?
$\approx$    $ \ \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 Tevatron w 7 )i7wop1cqb frm2i;yq48dnoith 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 ;o qi)2o1fp7 cydmi87rq4wbnfor 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 annihilabjc gv k;/1a-tte each othe1vtc ;g j/kba-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, and by what interaxi26ui)/njkt yg+6h f ction could they occur? For those forbidden, explain why. 2+ij6n x6 igk ft)yu/h
(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 could t4x1kyupfjrc n):0d +y wem y86h(x+ jihey occur? Fory1h 8imd+ x0j4 rp6e:ux+cynyk)(jf w 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 amj jpnmi-l 3ptw(v4dw6 i,8w ( $\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in th*uqpzw4gvq6*7w b 5 moe 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.ege *, eam-ph4lb(s:j 32-4, for producing a pion.m4*leaebhp : jg- se,( $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-value for the reactijumm 80,,bbcyjb7so7be bi i/ ,4utq2on $\pi^- + p \to \Lambda^0 + K^0$ 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 water molecule? +sn 5.hg n fnrng:8-ri   fermions

  A proton and an antiproton annihilate each other at rest and produce two piok:+oc 2(gpt1(n k8ky ieh cje*ns, 8cy1htkojg:e (*+ ie2pn(k kc$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-uqj 7jc;2lj7 sp7 ) zkpi83mwacalled 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 inlxxb7-o+a/i i((z8 tz3zy 9xffhe) d n Table 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 energxo y-(+ ld/87xh f atzini9(xezbz3f)y 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 in the following bk/c:eo .6twzov,bj/ reactions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to djvl rhv75-t8 hescribe the reaction $p + n \to \pi^+ + \pi^-$.

What fraction of the spef: t s9;2b70m za dtapx0o,gkced of light $c$ is the speed of a 7.0-TeV proton?