- - - - - - - - - - - - - - - - - -International Journal of Scientific & Engineering Research, Volume 4, Issue 12, December-2013 665
ISSN 2229-5518
Amol S Jagtap
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Interaction of photons with bound or free electrons of an atom has been an interesting topic
The possibility of existence of the “big”
electron having the certain size and the form when photon interacts with electron is proposed by J.J.
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in the academic as well as research areas. Photon
exhibits wave as well as particle nature according to wave- particle duality postulated by de Broglie. The effective mass of photon can be defined by the relation mphoton = [hν0 / (c2)] [1,2]. R. Manjunath [3] shown that photon carries mass proportional to its frequency and when photon interacts with the particle, mass of particle increases by an amount of the mass of photon. The elastic scattering of photon by free electron is discovered by J.J. Thomson [4]. A. H. Compton [4,5] described the inelastic scattering of photon by free orbital electron by process of billiard-ball collision between photon and free electron.
Corresponding Auther: Amol S Jagtap
Department of Radiotherapy, Cama & Albless Hospital, Mahapalika Marg,
Mumbai-400001, India.
Email: amol_jagtapm@yahoo.com
Thomson [4] and Neoclassical theory [6]. However,
the phenomenon of change in mass and size of electron during the interaction with photon by free electron is not clearly known. Here I have proposed new theory on absorption and re- emission of same energy photons by free electron which proves the existence of “big” electron during interaction.
“When the photon of energy E and mass (mp) interact with the free electron of rest mass (me), electron will absorb all the energy of incident photon in terms of photon mass, becomes unstable and goes into excited state from its ground state. While de-exciting from excited state, electron emits photon of energy equivalent to its excess mass isotropically”.
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International Journal of Scientific & Engineering Research, Volume 4, Issue 12, December-2013 666
ISSN 2229-5518
In this process, excited electron becomes
the new source of photon and emits the photon of same energy as that of incident photon. Therefore the energy of photon before and after the interaction is remains same.
Consider photons of energy E and mass mp incidents on free electron of rest mass me, Since the energy of photon is associated with its mass by Einstein mass-energy relation E=mp x c2, during the interaction of photon with electron, photon gives all its energy in terms of its mass mp, to the electron. Hence, the mass of electron increases by me + mp, becomes unstable and goes to the excited state with excitation energy equal to (me +mp) x c2 during time t1 which is shown in FIG.1.
time required to complete absorption and re-
emission of photon in this process in t1+t2. Where, t1 is the time required to get electron into excited state and t2 is the time required to get electron into ground state from excited state.
Let us consider,
Incident photon mass = mp
Incident photon energy = mp x c2
Rest mass of electron = me
Rest mass energy of electron = me x c2
Therefore,
According to conservation of mass and energy law,
mp + me = ( mp + me )* = me + mp
mp + me = (∆m)* = me + mp ------ (1)
Where, (∆m*) = me + mp , is the increase in
electron mass in excited state.
IJSEMultiplying bRoth side of equation (1) by c2 we
From excited state, electron comes to its
ground state by converting its excess mass in the form of electromagnetic radiation by process of E=∆m x c2 in time t2, where ∆m = (mp + me - me). In later process, the change in mass is converted into the energy and energy of emitted photon is equal to the energy of incident photon.
Here the excited electron becomes new source of photon and emits photon in all direction. The
get,
mp x c2 + me x c2 = (∆m x c2)* = me x c2 +mp x c2
----- (2)
mp x c2 + me x c2 = (∆E*) = me x c2 +mp x c2
Here, (∆m x c2)* = (∆E*) is the increase in rest
mass energy of electron in excited state
Equation (2) shows energy is conserved in this process i.e. incident energy and final energy of photon remains same. Therefore there is no energy loss of photon during interaction.
According to the law of conservation of momentum,
Initial momentum of photon = mp x c Final momentum of photon = mp x c Initial momentum of electron: 0
Final momentum of electron: 0
mp x c + 0 = 0 + mp x c ---- (3)
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International Journal of Scientific & Engineering Research, Volume 4, Issue 12, December-2013 667
ISSN 2229-5518
Equation (3) shows initial and final
momentum is also conserved in this process.
The classical electron radius is roughly the size the electron would need to have for its mass to be completely due to its electrostatic potential energy [7]. The classical electron radius, also known as the Thomson scattering length is given
by following equation:
scattering of photon if two photons interact
simultaneously with the same electron. This could also results in the inelastic scattering of photon by free electron in Compton scattering process. This theory can be useful for the study of fundamental properties of electron and other elementary particles in details. In the true sense, this is not the coherent or elastic scattering of photon by free electron; instead it is the absorption and re-
emission of photon by the free electron.
r = 1
e2
= 2.8179 ×10−15 m
e 4πε
m c2
0 e
------ (4)
Selvam (RP & AD, CT & CRS, BARC Mumbai,
Dirac suggests mathematic point like model
of electron for quantum electrodynamics theory.
India) for helpful discussion and comments on
manuscript.
Form the results of some experiments on the X and
γ rays it is assumed that electron may be flexible
ring or spherical shape distributed charge of
electricity with radius of order [5] 2.42 x 10-12 m.
Equation (4) shows radius of electron (re ) is inversely proportional to its mass. When photon interact with electron, the mass of electron increases by an amount of mass of photon (mp ), therefore there is decrease in radius of electron corresponding to mass of interacting photon and this change in radius of electron exists for the time interval of excitation and de-excitation of electron i.e. t1+t2.
Present theory considered the incident photon carries mass equivalent to its energy. It proves the existence of electron with greater mass and smaller radius when interacted with photon. This increase
in mass of electron could lead to the inelastic
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International Journal of Scientific & Engineering Research, Volume 4, Issue 12, December-2013 668
ISSN 2229-5518
[4] A.H. Compton, Quantum theory of the
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