Give a reaction between two nutz9-zf7l on x/cleons, similar to Eq. 32-4, that could produce a n7fzxz- t/9lo$\pi^0$.

  If a proton is moving ai.z;;f/jc)ti1*7jik: wab nn ucxl7 tt very high speed, so that its kinetic energy is much great l*b:/ z71knjtcxc)nfwat.i 7 ij; u;ier 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 of the antipa.h2pgawys:aj+q5 ,x nrticles to the constituents of normal atoms, consist of? What might happen if antimatter, made of such antiatoms, came in contact with our normal world of m pa5+nj.y q:awgsx,h2atter?

What particle in a decay signals the electromag w6txm 0sg,lj,k(0ax anetic interaction?

Does the presence of a neutrino among the decay produ)nhgj0c; ab*l6 cd0prigb5p+ts( yc9 cts of a particle necessarily mean that the decay occurs via the weak interaction? Do all decays viabtc+a )ih ;n ljr0yc cbgp(6p9g0 ds5* the weak interaction produce a neutrino? Explain.

Why is it that a neutron decays via the weak interaction even though the*r vnsn+5 e:cogr.lht;m.zpi, 9 +nfc neutron and one of its decay products (proton) are strongly interacting? r;mh vf5t n+o,gnce+ 9z .*.c:nsilrp

Which of the four interactions (strong, electromagnetic, weak, gravitational) d )kqsra :faav;*m:ir 1oes an electron take part in? makqr1* sir;:vfa: a)A neutrino? A proton?

Check that charge an5ux ,ildq8: hgd baryon number are conserved in each of the decays in Table 32-2. duq5l8ghx,:i

Which of the particle decays in Table 32-2 occur via the electromagnetic inaqknsc/jn15)a)fto r 4rj (; nteractq)a1 n4r/o snna5rtj )(c jf;kion?

Which of the particle decays in Table 32-2 occur by th ku8z *3dqtr8ee weak interaction?

By what interaction, and why, dxvm( gq, .pk1vx-.gg hoes $\Sigma^0$ 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 electrockcz ma8v7 5af*ie ;1amagnetic interaction?e1az; c8m75 a aic*fkv

Which of the particle decays ifxvk7c; h 31agn 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,xvzu ;lx81:* p4jejmx ga7s c, had no color charge or electrical charge, and did not feel the weak force. Could yo,a*mu1cx7 ;lv4x :gej8xp zs ju say that this particle even exists?

  Is it possible for a particle :rjc3, .cq zjds3/ 6priw )jurto 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, wonbdd5ai 09b oiw +r5a7uld it be possible to find particles made up of two quarks and no antiquarks? What about two quarka5 7ao 9+r0wi5bbdi nds and two antiquarks?

Why do neutrons decay when they are free but not when they are 9 vtdqj7 fi.qaocq x2bd8-r.7inside the nucleusa. d9bqc7r -dqfv2 8.qiojx7t ?

  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 is 6.3l/.gvtlx) 9o-kjkj5m6i*q wj5 GeV?    GeV

  Calculate the wavelength of 35-GeV electrons. E (r fdlxn;zg vr7za; :705 qwrv=    $\times 10^{-17}\ \text{m}$

  What strength of magnetic field is used in au e mo-p8:n4(usvj;) bhknu2 io0p(gn cyclotron in which protons make $2.8 \times 10^7$ revolutions per second? $f$ =    T

  What is the time for one complete revolution fo0elxcb- y.d7x9o 6uo kr a very high-energy proton in the 1.0-km-radius Fermilab acceeubdx .y79-6ookl x0clerator? 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 Example 32-2 accele yy+ qda.;yw847 w5xzg /eab. stoqey.rated $\alpha$ 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-MeVk78o5 s)bqqjp alpha particles or 30-MeV protons? Compare 7skp5)oq8qb jeach of their 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 5 +;wfy:(k pt*vu3v6ht0 ksnio5 kV. How many revolutions do protons make to reach a kinetic enn (ks:ituwt y *kv6+3fvh0po;ergy of 25 MeV? $\approx $    $\ \text{revolutions}$

  What is the wavelength ,exo7v)o)qjx ($\lambda$, maximum resolvable distance) of 7.0-TeV protons? E =    $\times 10^{-19}\ \text{m}$

  A cyclotron with a radius of fk ijwm 0aej3 n3pyrv*z1t-*7 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 house the magnets f+p enep a .ebg,e7uab;g:+m,b2 hq0u yor the Large Hadron Collider (LHC) calls for proton beams of energy 7.0 b 0pbpy ;bg hm,.2nu + eauge+e:7aq,eTeV. What magnetic field will be required? B =    T

  The 1.0-km radius Fermilab Tevatron takes about 20 seconds to br+ tg-9aqti2v h5aelw:4gh ls;ing the energies of the stored protons from 150 GeV to 1.0 TeV. The acceleration is done once per turn. Es gt2q le +ls5wa9: ;ah4vt-hgitimate 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 ofrf e4sujr8c7rwn)2zayi:v,( 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-radius Fe :p)rp)jjunu(6 b,ozv rmilab synchrotron for 1.0-TeV protons? B =up)z)vrup :6n, jjob(    T

  How much energy is releebflgz/v/bj 5*7f gn (ased in the decay $\pi^+ \to \mu^+ + \nu_\mu$? See Table 32–2.    MeV

  About how much energy is releag hew jiq(f l+dn:.x(vmt0i3.sed when a $\Sigma^+$ decays to $n + \pi^+$? (See Table 32–2.)    MeV

  How much energy is requiy-2ewnep8*s o red to produce a neutron-antineutron pair?    MeV

  Estimate the range of the strong force if the mediating particle were the kalwy/a 0wk ;xl,jv+rejf *2l:lo9 td *ul* g/aaon instead of the piodj*a l y lo*wekaxftlg/w*+2/jl0ula r,:;9vn. $mc^2$ $\approx$    $ \times 10^{-16}\ \text{m}$

  Two protons are heading toward each 3o ic0gjod6-7 * plfon:h aq,iother with equal speeds. What minimum kinetic ener c7l,f*ajon g360i-qh: id oopgy 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 jv, c cc76dgpy8 k1ox5have if they are traveling at the same speed toward each other, collide, and pr57ck1,yjvxoc 6gd p8coduce a $\pi^0$ pair in addition to themselves? (See Table 32-2.)    MeV

  Estimate the range of the weak force using Eq. 32-3ap+b oy nb(2h b5m5gp3, given the masses of the W and5mn h3a2p gyb+bb 5(po Z particles as about 80 to $90\ \text{GeV}/c^2$. $mc^2$$\approx $    $\times 10^{-18}\ \text{m}$

  What are the wavelengths of tpy( z2nwr bxn .ge/e;mz)6ioep a 42+ihe two photons produced when a proton and antiproton at rest annihilate? i42y6ea)o(z;b/.nwem ng p+2rp xi ze $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 imposv*h84g)b fix:p*xxsbo 4o j/n sible for an isolated electronh*xovfjxip 4gs4):*bobn x8 / to radiate 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 the twy wkv ,83 ;nhml;nvm/wo photons produced when an electron and a positron, each with 420 keV of k;nm v,w n;mlk 8wv/y3hinetic 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:w ;x*fya (;sq+2bo euld*x vism*3pb? For those forbidden, explain what laws are violate;dye*q:2 vm bix; *lx 3(a+bp us*sfowd.
(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 products in the deq6nrqe:*rndym - o .-kcay $\Xi^- \to \Lambda^0 + \pi^-$. 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 kinet(9 jl-lex hw-)yunid7ab46 wzic 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 the energy width ac0ye 2obtq9m.z d):qand 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 t3 b h+u57xlkso:m6 w nksir,djvkm 4+jmf0 ,/vhe $\Upsilon$ meson is 88 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  The measured width of th g: 1q 2 d2nhxqe2sddn)am*/zve $J/\psi$ (3685) meson is 277 keV. Estimate its lifetime. $\Delta E$ =    $ \times 10^{-21}\ \text{s}$

  What is the energy width (or uncrk9-k8chjx0 ; 7th iavertainty) 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 possibly0c(7n bl wzg/9 weo3 m/jh*die? For those that are forbidden, explailn*w w / i3cby/e9o(jdz7h gm0n 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 cowv8cg 3hz-j/q)rlpf 6mbinations that can form (a) a neutron, (b) an antineutron, jv-8r6q3zlpf )/ chwg(c) a $\pi^+$, (d) a $K^-$?

What particles do the following quark combinations p:e ;nkkgr63 zlc:el+wa 0do q,roduce: (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 producegl)l65j0baysi9n(z y 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 q q:i ex).v2uke-pyommy n4a.; uarks (as in Fig. Below) for the reactionmk e).:im.2 4pyvyua ;nqo-ex $p + \pi^- \to n + \pi^0$.

Draw a Feynman diagram for the b k;* uy/di;8;fvpvyireaction $n + \nu_\mu \to p + \mu^-$.

  What is the total energy of a proton whose kinetic energy is 25 GeV? Wha 3j r:4,ghaeout is its wa :rjeh,u4g3ao velength?
$\approx$    $ \ \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 wita z8w3 mo)btb/h an energy of 150 GeV. If they are accelerated by 2.5 MV each revolution, how far do they travel and approximately 8/m)batz3bo w how long does it take for them to reach 1.0 TeV? d$\approx $    $ \times 10^9\ \text{m}$

  (a) How much energy is relelxu1o+7wdyy/an.bat)qf2 2m ased when an electron and a positron annihilate each oo 7/+q ytdy12fxwual amb).n2ther? $E_{\text{total}}$=    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 rea n3i wpym5eht(o3 l j6mg55j.)1xgxim ctions are possible, and by what interaction could they occur? For those forb(pg55l.jxmm igjto 6nie 3y1wm5 3x)h idden, 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, and3:sismkxn w/di7u, /p by what interaction could they occur? For those forbidden, explisid/s7 x,wu 3p/:k nmain 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 r j s xc )d0 onglt735h6)mv+7fmeitj)$\pi^+$ is $\pi^+ \to \mu^+ + \nu_\mu$. What would be the equivalent decay for a $\pi^-$? Check conservation rules.

  Symmetry breaking occurs in the electroweak thbwtq + m):+ m1vytknh1eory 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-zmg ineu 2*kg)/jd41la(i, py4, for producing a pion.g2) dajy 1p/ze*g 4kii( lun,m $Q$ =   $MeV$ or $Q$ =    $MeV$

  Calculate the Q-valu) tqcwyj.*hp p+8m9l*s2f fmvozr z27h( jsh2e for 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 a water-59 akopfa9 : pjcb*ed molecule?    fermions

  A proton and an antiproton annihilate each other at rest and produce two pt0)z4 8t3 - ziejkuua,wflvk,ions, uw jtazzk3i,l, u0f4) kv8-et$\pi^-$ and $\pi^+$. What is the kinetic energy of each pion? $2m_pc^2$ =    MeV

  (a) Show that the so-called unis5)w d ohz2)0v-ljd jofication 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 e+vc60u 93 r sjg2qasmin 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 creavm0+6u2s9r 3 asgc jqeted with a kinetic energy 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 react 1eit(mx( nxl3ions.
(a) $p + p \to p + n + \pi^+ + ?$
(b) $p + ? \to n + \mu^+ + \nu_\mu$

Use the quark model to describe the reactivc4:fk sf5.9z sukb5r2gp/p kon $p + n \to \pi^+ + \pi^-$.

What fraction of the speed of l4,zdc 15ub(ad nn/x2*k cnvadight $c$ is the speed of a 7.0-TeV proton?