#initiation of variable
w=121.5; #lambeda
G=6.67*10**-11; #Various given values and constants
M= 1.99*10**30;
R= 6.96*10**8;
c=3*10**8;
#calculation
k= G*M/(R*c**2); #(delLambeda)/(lambeda)
delw=k*w; #del(lambeda)
#result
print "The change in wavelength due to gravitational shift in pm is",round(delw*10**3,3);
#part3
k=5.5*10**-5;#due to thermal Doppler broadening effect
delw=k*w;
#result
print "The change in wavelength due to thermal Doppler broadening effect in pm is",round(delw*10**3,3);
#initiation of variable
mp=938.280; #mass of various particles
me=0.511;
m2h=1875.628;
#calculation
mic2=2*mp; #mass energy on L.H.S
mfc2=m2h+me; #mass energy on R.H.S
Q=mic2-mfc2; #Q value of reation
pc=Q;
mc2=1875.628;
K=(pc**2)/(2*mc2); #kinetic threshold energy
Emax=Q-K; #maximum energy
#result
print "The maximum neutrino energy in MeV is",round(Emax,3);