Observations of Pt/Ne hollow cathode lamps similar to those used on the Cosmic Origins Spectrograph: spectroscopy and air testing

摘要

We report accelerated aging tests on three Pt/Ne lamps from the same manufacturing run as lamps installed on the Cosmic Origins Spectrograph (COS). Initial radiometrically calibrated spectra were taken for each lamp at the National Institute of Standards and Technology (NIST). One lamp was aged in air at NIST at a current of 10 mA and 50 % duty cycle (30 s on, 30 s off) until failure. Calibrated spectra were taken after 206 h, 500 h, 778 h, 783 h and 897 h of operation. Two other lamps were aged by the COS instrument development team in a thermal vacuum chamber, with calibrated spectra taken at NIST after 500 h of operation. In all three lamps, total output dropped by less than 15 % over 500 h. We conclude that the lamps will satisfy the requirements of COS in both lifetime and spectral stability.