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**SPHEROMAK STRUCTURE:**

This web page uses a simplified analysis to show that circulating static charge forms the external field energy density distribution required for the existence of a spheromak. The more elaborate mathematical proof of spheromak wall position stability is developed on the web page titled:THEORETICAL SPHEROMAK. The electric and magnetic fields of a spheromak maintain its toroidal geometry and to hold a stable amount of energy.

A spheromak toroid has a major axis and a minor axis. The charge motion closed spiral path is characterized by **Np** turns around the toroid's major axis and by **Nt** turns around the toroid's minor axis. This charge motion path has the toroidal shape of the glaze on a doughnut and is referred to as the spheromak wall. Inside the spheromak wall the magnetic field is toroidal. Outside the spheromak wall the magnetic field is poloidal. Inside the spheromak wall the electric field is cylindrically radial. Outside the spheromak wall the electric field is spherically radial. The spacial distribution of the circulating charge is constant over time. Hence the electric and magnetic field geometry is constant over time.

The spheromak field structure allows semi-stable plasma spheromaks and discrete stable atomic charged particles to exist and act as stores of energy.

**ELEMENTARY SPHEROMAK:**

A plan view of the charge path of an elementary spheromak with Np = 3 and Nt = 4 is shown below. The blue lines show the charge path on the upper face of the torus. The red lines show the charge path on the lower face of the torus. Note that the charge path never intersects itself except at the point where the charge starts to retrace its previous path.

In the diagram yellow shows the region of toroidal magnetic field. Outside the yellow region is a poloidal magnetic field and a spherical electric field.

In a real stable charged particle typically Np = 222 and Nt = 305 so the numbers of charge path poloidal and toroidal turns is much greater in a real spheromak than is shown on this simple diagram.

This elementary spheromak winding pattern was generated using a polar graph and formulae of the form:

R = Rc + K [t - t(2N)] where t(2N) = (2 N) (3 Pi / 4) and t(2N) < t < t(2N+1)

and

R = Rs - K [t - t(2N + 1)]

where:

t(2N + 1) = (2N + 1)(3 Pi / 4)

and

t(2N + 1) < t < t(2N + 2)

where:

N = 0, 1, 2, 3.
Use:

Rc = 1000,

Rs = 4105,

K = (4140 / Pi)

Top to bottom connection points were depicted by adjusting the torus Rs to 4045 and Rc to 1060.

**ATOMIC PARTICLE SPHEROMAKS:**

Atomic particle spheromaks consist of quantized charge that superficially appears to be at rest with respect to an inertial observer. Isolated stable atomic particles such as electrons and protons hold specific amounts of energy (rest mass). When these particles aggregate the assembly emits photons. This photon emission decreases the total amount of energy in the assembly creating a potential energy well.

In an atomic particle spheromak current moves uniformly around a closed spiral path. The net charge motion is at the speed of light. The spheromak net charge is uniformly distributed along the charge path. The uniform charge distribution along the charge motion path and uniform charge motion cause constant electric and magnetic fields. The time until an element of charge retraces its previous path is (1 / Fh) where Fh is the characteristic frequency of the spheromak.

A spheromak in free space has a round cross section. However, the fields of an atomic particle spheromak may be distorted by external electric and magnetic fields.

Einstein's formula:

**Ett = Mp C^2**

gives the total energy of an isolated proton at rest as:

Ett = 1.67262 X 10^-27 kg X (2.99792458 X 10^8 m / s)^2

= **15.03275887 X 10^-11 J**.

The magnetic moment of a proton is:

1.4106067 X 10^-26 J / T

The Larmor precession frequency for a proton is:

42.57748 MHz / T

Einstein's formula:

**Ett = Me C^2**

gives the total energy of an isolated electron at rest as:

Ett = 9.109383 X 10^-31 kg X (2.99792458 X 10^8 m / s)^2

= **81.87105146 X 10^-15 J**.

The magnetic moment of an electron is:

-928.4763 X 10^-26 J / T

**PLASMA SPHEROMAKS:**

Plasma spheromaks are composed of free electrons and ions that move along a stable closed path at less than the speed of light.
Plasma spheromaks can be generated and photographed in a laboratory. A plasma spheromak in free space has a nearly round cross section. However, in a laboratory the field configuration of a plasma spheromak is affected by the proximity of a metal enclosure containment wall. If the equatorial outside radius **Rs** of a spheromak approaches the inside radius **Rw** of an enclosure's cylindrical wall the spheromak loses stability because the external field energy distribution becomes cylindrical rather than spherical.

The image below shows a plasma spheromak photograph made by General Fusion Inc.

An important feature of this photograph is the ratio of the spheromak outside radius Rs to its inside radius Rc. On this photograph the ratio:

**(Rs / Rc) ~ 4.2**.

However, this ratio may be affected by the proximity of the enclosure wall. Theoretical analysis on this web site indicates that in free space this ratio is close to:

**(Rs / Rc) = 4.1047**.

For plasma spheromak stability there must be a slight separation between the positive ion and negative electron paths to prevent inter-particle scattering. Further, to prevent further scattering and loss of energy from energetic plasma free electrons the concentration of neutral ionizable atoms in the vacuum chamber containing the spheromak must be very small.

The amount of field energy trapped by a plasma spheromak can be significant. In the Plasma Impact Fusion (PIF) process the total field energy **Ett** of each injected plasma spheromak, above and beyond the total field energy of the plasma spheromaks constituant particles, must be at least: **3000 J**.

**SPHEROMAK CONCEPT:**

Conceptually a spheromak wall is a toroidal surface formed from the closed charge path of a spheromak. The direction of the charge path axis within the spheromaki wall conforms to the toroid surface curvature.

The charge path forming a spheromak has both toroidal and poloidal magnetic field components. The charge path axis gradually changes direction over the surface of the toroid following a spiral.

In a spheromak quantized positive and negative charge moves along a spiral path tangent to the spheromak wall. A spheromak is cylindrically symmetric about the spheromak major axis and is mirror symmetric about the spheromak's equatorial plane. The net charge **Qs** is uniformly distributed over the charge path length **Lh**.

In the central core of the spheromak the electric field is zero. In the toroidal region enclosed by the spheromak wall the magnetic field is purely toroidal and the electric field is cylindrically radial. In the region outside the spheromak wall the magnetic field is purely poloidal. Outside the spheromak wall the electric field is spherically radial. The charge circulate in the narrow low magnetic field region at the interface between the toroidal and poloidal magnetic fields within the spheromak wall.

**LOCATION IN A SPHEROMAK:**

A spheromak has both cylindrical symmetry about its main axis of symmetry and has mirror symmetry about its equatorial plane. A position in a spheromak can be defined by:

**(R, H)**

where:

**R** = radius from the main axis of cylindrical symmetry;

and

**H** = height above (or below) the spheromak equatorial plane.

**SPHEROMAK CROSS SECTIONAL DIAGRAM:**

The following diagram shows the approximate cross sectional shape of a real spheromak within a cylindrical enclosure.

Note that an ideal spheromak in free space has a round toroidal cross section whereas a real spheromak may be radially distorted by the proximity of metal enclosure walls.

**GEOMETRICAL FEATURES OF A SPHEROMAK:**

Important geometrical features of a spheromak include:

**Rc** = the spheromak wall inside radius on the equatorial plane;

**Rs** = the spheromak wall outside radius on the equatorial plane;

**Rf** = the value of R at the spheromak end where: H = Hf;

**(2 |Hf|)** = the overall spheromak length;

**Np** = number of poloidal charge hose turns about the major axis of symmetry;

**Nt** = number of toroidal charge hose turns about the minor axis in the spheromak;

The subscript **c** refers to spheromak "core" surface on the equatorial plane;

The subscript **f** refers to the "funnel edge" at the spheromak end;

The subscript **s** refers to the spheromak outer "surface" on the equatorial plane.

In order to understand the material on this web page it is essential for the reader to study the spheromak cross sectional diagram and to identify the above mentioned parameters.

When a unit of charge has passed through the spheromak core hole **Nt** times it has also circled around the main axis of spheromak symmetry **Np** times, after which it reaches the point in its closed path where it originally started.

Define:

**Lt** = one purely toroidal turn length;

**Lp** = one average purely poloidal turn length;

Then due to the orthogonality of toroidal and poloidal directions the charge hose or plasma hose length **Lh** is given by:

**Lh^2 = (Nt Lt)^2 + (Np Lp)^2**

**SPHEROMAK SHAPE:**

Lp = 2 Pi [(Rs + Rc) / 2]

= Pi (Rs + Rc)

Lt = 2 Pi [(Rs - Rc) / 2]

= Pi (Rs - Rc)

(Lp / Lt) = [Pi (Rs + Rc)] / [Pi (Rs - Rc)]

= (Rs + Rc) / (Rs - Rc)

or

(Rs - Rc)(Lp / Lt) = (Rs + Rc)

or

Rs [(Lp / Lt) - 1] = Rc [(Lp / Lt) + 1]

or

**(Rs / Rc)** = [(Lp / Lt) + 1] / [(Lp / Lt) - 1]

= **[Lp + Lt] / [Lp - Lt]**

Thus the shape of the spheromak is defined by the ratio:

**So^2 = (Rs / Rc)**.

The energy and frequency of a spheromak also involve **Np** and **Nt**.

There are **Nt** parallel charge hoses that go through the equatorial plane in the central core of the spheromak and hence form the spheromak inner wall.

**SPHEROMAK PARAMETER DEFINITIONS:**

The remainder of this web page is devoted to mathematical analysis of undistorted ideal spheromaks.

Define:

**Ue** = electric field energy density as a function of position, Ue = 0 at R = 0, H = 0;

**Um** = magnetic field energy density as a function of position;

**U = Ue + Um** = total field energy density as a function of position;

**Uo** = maximum total field energy density at R = 0, H = 0;

**Ueo = Uo** = electric field energy density coefficient;

**Umo = (Bpo^2 / 2 Mu) = Uo** = maximum magnetic field energy density at R = 0, H = 0;

**Upo = Uo** = maximum poloidal field energy density at R = 0, H = 0;

**R** = radial distance of a point from the major axis of symmetry of spheromak;

**H** = distance of a point above the spheromak equatorial plane (H is negative for points below the equatorial plane);

**Ro** = nominal spheromak radius defined by: **Ro^2 = Rs Rc**

**(Rx, Hx)** = a point **X** located at **R = Rx, H = Hx**

**Hf** = maximum value of **|H|** on the spheromak charge sheet

**2 Hf** = spheromak overall length

**Rf** = radius of spheromak charge sheet at **H = Hf** and **H = -Hf**

**Lpo = 2 Pi Ro = 2 Pi (Rs Rc)^0.5**

**Lp = Pi (Rs + Rc)**

**Lt = Pi (Rs - Rc)**

**Uc** = total field energy density at **R = Rc, H = 0**

**Hs** = spheromak wall height at radius R defined by:

**Hs^2 = (Rs - R)(R - Rc)**

**Ut(R) = Uc (Rc / R)^2** = energy density function inside the toroidal shaped spheromak wall

**Up(R, H) = Upo [Ro^2 / (Ro^2 + R^2 + H^2)]^2** = poloidal magmetic plus spherical electric energy density function outside the spheromak wall

**(Rx, Hx)** = a point located at **R = Rx, H = Hx**

**SPHEROMAK CHARGE HOSE PARAMETERS**

Define:

**Ih** = charge hose current;

**Lh** = length of closed loop of charge hose;

**Dh** = center to center distance between adjacent charge hoses

**As** = outside surface area of spheromak wall

**Q** = proton net charge

**Qs** = net charge on spheromak

**Nnh** = integer number of negative charge quanta

**Nph** = integer number of positive charge quanta

**Vn** = velocity of negative charge quanta along charge hose

**Vp** = velocity of positive charge quanta along charge hose

**C** = speed of light

**CHARGE HOSE LENGTH:**

Due to orthogonality of toroidal and poloidal charge hose turns:

**Lh^2 = (Np Lp)^2 + (Nt Lt)^2**

**SPHEROMAK CHARGE DISTRIBUTION ASSUMPTION:**

Assume that the spheromak charge is uniformly distributed along the charge hose length.

**EQUATORIAL PLANE:**

On the spheromak's equatorial plane:

**H = 0**

For points on the spheromak's equatorial plane the following statements can be made:

For **R < Rc** the radial electric field is zero;

For **R < Rc** the toroidal magnetic field **Btoc = 0**

For **R < Rc** the magnetic field **Bpoc** is purely poloidal;

For **R = 0** the magnetic field is parallel to the axis of cylindrical symmetry;

For **Rc < R < Rs** the electric field **Er** is cylindrically radial;

For **Rc < R < Rs** the electric field **Er** is proportional to **(1 / R)**;

For **Rc < R < Rs** the poloidal magnetic field **Bpit = 0**;

For **Rc < R < Rs** the toroidal magnetic field **Btit** is proportional to **(1 / R)**.

For **Rs < R** in free space the electric field **Ero** is spherically radial;

For **Rs < R** in free space the electric field **Ero** is proportional to **(1 / R^2)**;

For **Rs < R** in free space the toroidal magnetic field **Bto = 0**;

For **Rs < R** in free space far field the poloidal magnetic field **Bpo** is proportional to **(1 / R^3)**;

**CHARGE HOSE CURRENT:**

**Ih = [Qp Np Vp + (- Q Ne Ve)] / Lh**

**CHARGE HOSE LENGTH Lh:**

Lh = {[2 Pi Np (Rs + Rc) / 2]^2 + [2 Pi Nt (Rs - Rc) / 2]^2}^0.5

= Pi {[Np (Rs + Rc)]^2 + [Nt (Rs - Rc)]^2}^0.5

= Pi Nt {[Nr (Rs + Rc)]^2 + [(Rs - Rc)]^2}^0.5

= Pi Nt Rc {[Nr (So^2 + 1)]^2 + [(So^2 - 1)]^2}^0.5

**CHARACTERISTIC FREQUENCY Fh:**

A spheromak's characteristic frequency Fh is given by:

Fh = C / Lh

where:

C = speed of light.

**AXIAL ELECTRIC FIELD ENERGY DENSITY DUE TO A RING OF CHARGE:**

Assume that a thin ring of radius "Ro" has net charge Qs. Then the linear charge density along the thin ring is:

Qs / (2 Pi Ro)

and an element of charge is:

dQ = [Qs / (2 Pi Ro)] dL

where dL is an element of the ring's circumferential length.

Consider a point at distance "Z" along the ring axis, where Z = 0 on the ring plane.

The electric field along distance (Ro^2 + Z^2)^0.5 due to charge dQ is:

dE =(1 / 4 Pi Epsilon) [dQ / (Ro^2 + Z^2)]

where:

Epsilon = permittivity of free space

The component of this electric field along the ring axis is:

dE = (1 / 4 Pi Epsilon) [dQ / (Ro^2 + Z^2)] cos(Theta)

where:

cos(Theta) = Z / (Ra^2 + Z^2)^0.5

The net electric field E at distance Z along the ring axis is:

E = (1 / 4 Pi Epsilon) [Qs / (Ro^2 + Z^2)] cos(Theta)

= (1 / 4 Pi Epsilon) [Qs / (Ro^2 + Z^2)] [Z / (Ro^2 + Z^2)^0.5]

= (1 / 4 Pi Epsilon) [Qs Z / (Ro^2 + Z^2)^1.5]

The electric field energy density Ue at Z = Z, R = 0 is given by:

Ue = (Epsilon / 2) E^2

= (Epsilon / 2){(1 / 4 Pi Epsilon) [Qs Z / (Ro^2 + Z^2)^1.5]}^2

= [Qs^2 / (32 Pi^2 Epsilon)] [Z^2 / (Ro^2 + Z^2)^3]

= [Mu C^2 Qs^2 / (32 Pi^2)] [Z^2 / (Ro^2 + Z^2)^3]

Note that at Z = 0 the net electric field is zero and the electric field energy density is zero.

In the far field where:

Z >> Ro

then along the ring axis in the far field:

Ue = [Qs^2 / (32 Pi^2 Epsilon)] [1 / Z^4]

Thus for Z >> Ro along the ring axis the electric field energy density Ue is proportional to (1 / Z)^4.

**AXIAL EXTERNAL MAGNETIC FIELD ENERGY DENSITY DUE TO A RING OF CURRENT:**

The law of Biot and Savart gives an element of magnetic field **dB** at a measurement point on the axis of a ring due to an electric current I is:

**dB** = (Mu / 4 Pi) Ip **dL X R** / |R|^3

where:

Ip = poloidal current around the ring

|R| = distance from current element Ip **dL** to the measurement point

Mu = magnetic permeability of free space

**dL** = an element of length along the direction of electric current flow around the ring

[**R / |R|]** = unit vector along the direction of R

Consider a ring of radius "Ro" and an axial measurement point at distance "Z" from the current ring along the ring axis.

Then along the ring axis the net magnetic field **B** at the measurement point is axial and is given by:

**B** = [(Mu / 4 Pi) Ip 2 Pi Ro / (Ro^2 + Z^2)] sin(Theta)

where:

(Theta) = angle between unit vector (**R** / |R|) and the ring axis.

However:

sin(Theta) = Ro / (Ro^2 + Z^2)^0.5

Thus the net magnetic field **B** along the current ring axis due to ring current I is given by::

**B** = [(Mu / 4 Pi) Ip 2 Pi Ro / (Ro^2 + Z^2)] sin(Theta)

= [(Mu / 4 Pi) Ip 2 Pi Ro / (Ro^2 + Z^2)][ Ro / (Ro^2 + Z^2)^0.5]

= [(Mu Ip) / 2] [Ro^2 / (Ro^2 + Z^2)^1.5]

The magnetic field energy density along the ring axis at Z = Z is:

Um = B^2 / 2 Mu

= [(Mu Ip) / 2]^2 [Ro^2 / (Ro^2 + Z^2)^1.5]^2 / 2 Mu

= [Mu Ip^2 / 8] [Ro^4 / (Ro^2 + Z^2)^3]

Thus for Z >> Ra the magnetic field energy density Um is proportional to (1 / Z)^6. Hence at large distances the magnetic field energy density becomes negligibly small as compared to the electric field energy density.

At the center of the ring where Z = 0 the magnetic field is:

**Bpo = [(Mu Ip) / (2 Ro)**

The corresponding magnetic field energy density Umo at the center of the ring is:

Umo = Bpo^2 / 2 Mu

= [Mu Ip^2 / 8 Ro^2]

Note that Umo is the magnetic field energy density at R = 0, H = 0 corresponding to current Ip circulating at R = Ro.

Along the ring axis the total electromagnetic energy density U is given by:

**U** = Ue + Um

= [Mu C^2 Qs^2 / (32 Pi^2)] [Z^2 / (Ro^2 + Z^2)^3] + [Mu Ip^2 / 8] [Ro^4 / (Ro^2 + Z^2)^3]

= [Mu C^2 Qs^2 / (32 Pi^2)] {[Z^2 / (Ro^2 + Z^2)^3] + {[Mu Ip^2 Ro^2 / 8] /[Mu C^2 Qa^2 / (32 Pi^2)]} [Ro^2 / (Ro^2 + Z^2)^3]

**If:**

{[Mu Ip^2 Ro^2 / 8] /[Mu C^2 Qs^2 / (32 Pi^2)]} = 1

or if:

{[ Ip^2 Ro^2 ] / [ C^2 Qs^2 / (4 Pi^2)]} = 1

or if

{[ Ip^2 Ro^2 4 Pi^2 ] / [ C^2 Qs^2]} = 1

or if:

{[ Ip Ro 2 Pi ] / [ C Qs]} = 1

or if

**Ip = C Qs / (2 Pi Ro)**

then the total energy density U is given by:

U = **[Mu C^2 Qs^2 / (32 Pi^2)] [1 / (Ra^2 + Z^2)^2]**

Assume that the net static charge Qs circulates around the ring at the speed of light or that Qs is a net charge consisting of both positive and negative charges circulating in opposite directions so that the requirement on Ip is met. This is the basic condition for the existence of a spheromak. In order to exist a spheromak requires both a net charge Qs and a poloidally circulating current Ip. As shown on the web page titled PLASMA HOSE the charge hose existence requires that:

Ih = Qs C / Lh

Note that the net charge Qs of an atomic particle might consist of the sum of positive and negative charge quanta known as quarks that individually circulate at less than the speed of light, but due to the constraints of charge hose behave as if the net charge is circulating at the speed of light. Hence:

Ip = [Qs C / 2 Pi Ro]

giving:

Upo = [Mu Ip^2 / 8 Ra^2]

= [Mu [Qs C / 2 Pi Ro]^2 / 8 Ro^2]

= [(Mu Qs^2 C^2) / (32 Pi^2 Ro^4)]

The magnetic field energy density Um along the ring axis is given by:

Um = [Mu Ip^2 / 8] [Ro^4 / (Ro^2 + Z^2)^3]

= [Mu [Qs C / 2 Pi Ro]^2 / 8] [Ro^4 / (Ro^2 + Z^2)^3]

= [Mu Qs^2 C^2 / 32 Pi^2] [Ro^2 / (Ro^2 + Z^2)^3]

Ue = [Mu C^2 Qs^2 / (32 Pi^2)] [Z^2 / (Ro^2 + Z^2)^3]

**TOTAL FIELD ENERGY DENSITY OUTSIDE THE SPHEROMAK WALL:**

The magnetic field energy density Um along the ring axis is given by:

Um = [Mu Qs^2 C^2 / 32 Pi^2] [Ro^2 / (Ro^2 + Zb^2)^3]

Recall that the electric field energy density Ue along the ring axis was given by:

Ue = [Mu C^2 Qs^2 / (32 Pi^2)] [Z^2 / (Ro^2 + Z^2)^3]

Then along the ring axis the total field energy density U is given by:

U = Um + Ue

= [Mu Qs^2 C^2 / 32 Pi^2] [Ro^2 / (Ro^2 + Z^2)^3] + [Mu C^2 Qs^2 / (32 Pi^2)] [Z^2 / (Ro^2 + Z^2)^3]

= [Mu Qs^2 C^2 / 32 Pi^2]{[Ro^2 / (Ro^2 + Z^2)^3] + [Z^2 / (Ro^2 + Z^2)^3]}

= [Mu Qs^2 C^2 / 32 Pi^2]{[(Ro^2 + Z^2) / (Ro^2 + Z^2)^3]

= **[Mu Qs^2 C^2 / 32 Pi^2] / [(Ro^2 + Z^2)^2]**

This expression, which applies along the axis of a thin charge and current ring of radius Ro, suggests several likely features of the energy density function of a spheromak outside the spheromak wall. At the center of the spheromak where Z = 0, Ue = 0 the energy density must be finite at about:

Uo = Umo = [Mu Qs^2 C^2 / 32 Pi^2 Ro^4]

and elsewhere along the spheromak axis the total energy density will likely be given by:

U = [Mu Qs^2 C^2 / 32 Pi^2] / [(Ro^2 + Z^2)^2]

The spacial geometry of a spheromak is more complicated than a thin charge and current ring. However, the above simple analysis gives an indication of the general form of a spheromak's energy density function outside the spheromak wall. The advantage of the above analysis is that it is simple. It is easy to get lost in the mathematical complexity of the detailed spheromak analysis.

However, in general the distance from the center of the spheromak is (R^2 + H^2) and the effective spheromak radius is Ro so we can reasonably guess that the spheromak total energy density function outside the spheromak wall will likely take the form:

**U** = [Mu Qs^2 C^2 / 32 Pi^2] / [(Ro^2 + R^2 + H^2)^2]

= [Mu Qs^2 C^2 / 32 Pi^2 Ro^4] [(Ro^2) / (Ro^2 + R^2 + H^2)]^2

= **Uo [(Ro^2) / (Ro^2 + R^2 + H^2)]^2**

where:

**Uo = [(Mu Qs^2 C^2) / (32 Pi^2 Ro^4)]**

Then the magnetic field energy density outside the spheromak wall will likely be:

**Um = Umo [(Ro^2 Ro^4) / (Ro^2 + R^2 + H^2)^3]**

and the electric field energy density outside the spheromak wall will likely be:

**Ue = Ueo [((R^2 + H^2) Ro^4) / (Ro^2 + R^2 + H^2)^3]**

where:

**Umo = Ueo = Uo**

Note that:

**U = Um + Ue**

= Umo [(Ro^2 Ro^4) / (Ro^2 + R^2 + H^2)^3] + Ueo [((R^2 + H^2) Ro^4) / (Ro^2 + R^2 + H^2)^3]

= Uo [((Ro^2 Ro^4) + (R^2 + H^2) Ro^4) / (Ro^2 + R^2 + H^2)^3]

= Uo [Ro^4 / (Ro^2 + R^2 + H^2)^2]

**= Uo [Ro^2 / (Ro^2 + R^2 + H^2)]^2**

as expected.

This web page last updated February 4, 2018.

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