RU171557U1 - A device for igniting a discharge in an atomic hydrogen source for an atomic maser - Google Patents

Abstract

The utility model relates to the field of optical instrumentation and relates to a device for igniting a discharge in an atomic hydrogen source for an atomic maser. The device includes an RF generator located in the housing for ignition of an RF discharge, a discharge flask, and an ultraviolet radiation source. The discharge flask is connected to the system of admission and evacuation of hydrogen atoms. The source of ultraviolet radiation is installed so that the RF field generated by the RF generator is sufficient to ignite the discharge in the discharge flask. The technical result consists in increasing the reliability of ignition of an RF discharge. 3 s.p. f-ly. 1 ill.

Description

The utility model relates to atomic frequency standards and can be used as a device for igniting a discharge in an atomic hydrogen source when creating active and passive quantum hydrogen frequency standards (hydrogen masers) to obtain highly stable oscillations.

One of the main elements of a hydrogen maser is a source of hydrogen atoms with an RF generator [1] and a vacuum pump with a sorting magnet and a thermostatically controlled, shielded from magnetic fields microwave resonator located inside the path of a beam of hydrogen atoms, inside which there is a storage discharge bulb that is connected to the system of admission and evacuation of hydrogen atoms [2].

In a hydrogen maser, atomic hydrogen is produced in the source of atomic hydrogen by dissociation of molecular hydrogen in a discharge flask when a high-frequency (HF) electric discharge is excited in it at a low pressure (HF generator).

Studies have shown that the ignition voltage of an RF discharge in a discharge flask increases with time due to aging of the flask walls, the accumulation of impurities in the volume and on the inner surface of the discharge flask, as well as other poorly studied factors, which is a common drawback (technical problem) of known designs of hydrogen masers. In this regard, the voltage of the RF field created by the RF generator, at some points in time, is lower than the ignition voltage of the discharge (but higher than the burning voltage), therefore, the discharge in the bulb does not ignite and the dissociation of molecular hydrogen does not occur, which is a technical problem of known analogues , the solution of which is carried out by the claimed design of the proposed device.

Closest to the claimed device is the design of the device for igniting an RF discharge in a source of hydrogen atoms of a hydrogen maser, described in [1], using an RF discharge created by an RF generator.

The technical result provided by the utility model is to increase the reliability of ignition of an RF discharge in a discharge flask of an atomic hydrogen source of a maser and, accordingly, the operational efficiency of quantum hydrogen frequency standards created on their basis.

The solution to this problem is achieved by the fact that an ultraviolet source is introduced into the device for igniting a discharge in an atomic hydrogen source for an atomic maser, including an RF generator (main) located in the housing for igniting an RF discharge in a discharge flask connected to a system for introducing and pumping out hydrogen atoms radiation (UVI), set so that its radiation lowers the ignition voltage of the RF discharge in hydrogen, as a result of the intensity of the RF field created by the main RF generator, it is enough to ignite row in the discharge flask.

The UVI source is made in the form of an electrodeless mercury lamp with a switch-off source of its combustion installed in front of and coaxially with a hole made in the base of the housing under the RF generator and coaxially with the discharge bulb.

To carry out the shielding of external devices from radiation from the UVI source, the area of the mercury lamp with its burning source is closed by a shielding cover.

In embodiments of the device for shielding RF radiation and eliminating interference from one (main) RF generator to the UV radiation source, the hole is closed with a metal grid, and a reflector is installed behind the UV radiation source to focus it.

The figure schematically shows a General view (longitudinal section) of the claimed device.

A device for igniting a discharge in an atomic hydrogen source contains an RF generator 2 located in the housing 1 (an RF radiation source) for igniting an RF discharge in a discharge flask 3 connected to a system for introducing and pumping out hydrogen atoms (not shown in the figure), an ultraviolet radiation source in the form of a mercury lamp 4 with a switchable source of combustion 5 (additional RF generator). To extinguish the mercury lamp, a time relay is used (not shown in the figure), which disables the source of the RF field 5, which supports the combustion of the mercury lamp 4, automatically after a while. A mercury lamp 4 is installed in front and coaxially with a hole 6 made in the base 7 of the housing 1 under the RF generator 2 (which is coaxially mounted to the discharge bulb 3). The hole 6 itself is closed with a metal mesh 8.

The area of the mercury lamp 4 with its burning source 5 is closed by a shielding cover 9.

In an embodiment of the ignition device behind the mercury lamp, a reflector (not shown) can be installed.

The operation of a hydrogen maser directly depends on the initial process of dissociation of molecular hydrogen upon excitation in a discharge flask of an RF discharge. The introduction of a source of ultraviolet radiation in the form of a mercury lamp 4 into the region of the RF generator 2, reducing the voltage of the discharge ignition and the formation of plasma, improves the stability of the initial process of molecular hydrogen dissociation. This is due to the fact that mercury has a wide (linear) emission spectrum and one of its emission lines coincides in frequency with the hydrogen emission line. It is on this spectral line that additional energy is transferred from the mercury lamp to hydrogen molecules, which leads to a decrease in the ignition voltage of the plasma discharge and the dissociation of molecules.

After ignition and plasma formation, the radiation of the mercury lamp is extinguished. Since at this time the need for its emission disappears, since the burning voltage of the RF discharge is lower than the ignition voltage and the field strength created by the RF generator, which was insufficient for the primary ignition of the discharge, is sufficient to maintain combustion.

Thus, it becomes possible to increase the reliability of ignition of the RF discharge in the discharge flask of the maser atomic hydrogen source and, accordingly, the reliability of the atomic hydrogen source, and, ultimately, the hydrogen frequency standard that it is part of. This is especially important in the conditions of operation of frequency standards in the equipment of the GLONASS space navigation system.

Literature

1. “Standards of frequency and time based on quantum generators and discriminators” edited by B.P. Fateeva, M., “Sov. Radio, 1978 p. 59, fig. 2.10.

2 Utility model RU patent No. 87836.

Claims (4)

1. A device for igniting a discharge in an atomic hydrogen source for an atomic maser, including an RF generator located in the housing for igniting an RF discharge in a discharge flask connected to a system for introducing and pumping out hydrogen atoms, characterized in that an ultraviolet radiation source installed therein is installed so that the RF field strength generated by the RF generator is sufficient to ignite the discharge in the discharge flask. 2. The device for igniting a discharge in a source of atomic hydrogen for an atomic maser according to claim 1, characterized in that the source of ultraviolet radiation is made in the form of a mercury lamp with a switchable source of its combustion, installed in front of and aligned with the hole made in the base of the housing under the RF generator . 3. The device for igniting a discharge in a source of atomic hydrogen for an atomic maser according to claim 2, characterized in that the hole is closed by a metal mesh. 4. The device for igniting a discharge in an atomic hydrogen source for an atomic maser according to claim 2, characterized in that a reflector is installed behind the ultraviolet radiation source.

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