Observations of Pt-Ne hollow cathode lamps similar to those used on the Cosmic Origins Spectrograph: photometry and vacuum testing

摘要

We report accelerated vacuum aging tests on two Pt-Ne lamps identical and/or similar to those installed on the Cosmic Origins Spectrograph (COS) to be installed in the Hubble Space Telescope (HST) in the fall of 2008. One additional lamp was aged in air at the National Institute of Standards and Technology (NIST). All lamps were tested at a 50% duty cycle (30 s on/off) at flight nominal (10 mA) constant current until failure. Calibrated spectra of all lamps were taken at NIST using the 10.7-m normal incidence vacuum spectrograph at various points in the life of the lamps. In this paper we report the results of the photometric, electrical, and thermal monitoring of the vacuum tested lamps, while the spectroscopic and air aging results are given in a companion paper (Nave et al., 2008, SPIE 7011-134). We conclude that the lamps will satisfy the requirements of the HST/COS mission in terms of lifetime, cycles, and thermal and spectral stability.