X-ray periodicities in sources observed by the RXTE ASM

The X-ray intensities measured from 230 X-ray sources observed by the RXTE All-Sky Monitor (ASM) were analyzed for periodic behavior. The ASM has been observing sources for nine years in the 1.5-12 keV energy range. In this search, we investigated a frequency range of 5 d⁻¹ to 144 d⁻¹ for periodic modulation. The search was carried out by applying the Fast Fourier Transform on the ASM data and whitening the resulting power density spectrum using a local averaging technique. A power threshold was set to determine the statistical significance of a peak in the power density spectrum. The search verified the orbital frequencies of four known X-ray binaries and also identified four previously unreported periodicities. The 5.7232 d⁻¹ orbital frequency of GX 9+9 was observed for the first time in ASM data, although this modulation had been observed before. The 6.0999 d⁻¹ peak found for XTE J1723-376 has not been reported before and may be an orbital frequency.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2005

Author dc:creator

• Shivamoggi, Vasudha B

Advisor dc:contributor.advisor

• Alan M. Levine.

• Physics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/32909

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/32909