Study of ultra-high energy emission from Cygnus X-3 and Hercules X-1
The CYGNUS experiment, consisting of an extensive air shower detector and a muon detector, was built at Los Alamos, New Mexico (latitude 36 N, longitude 107W, altitude 2310 meters), to search for point sources of ultra-high energy (>10/sup 14/ eV) particles. These particles must be long-lived neutral particles because of the long source distances and the presence of the intragalactic magnetic field. Gamma rays are the most likely candidates because of the short neutron lifetime and the small neutrino cross section. Therefore, the muon content of the source showers is examined to determine if these events are muon poor as is expected for gamma-initiated showers. The data set from April 1986 to July 1987 is searched for continual emission from Cygnus X-3 and Hercules X-1, and an upper bound to flux is determined for both sources. The flux limit for Cygnus X-3, 2.0 /times/ 10/sup /minus/13/ cm/sup /minus/2/ sec/sup /minus/1/ above 50 TeV, is lower than previous ultra-high energy observations. Hercules X-1 has never been observed continually at ultra-high energies. Cygnus X-3 is observed for a shorter interval of time, beginning on 17 April 1986 and ending 1 June 1986. There is one chance in 300 that the observation is due to a random fluctuation. The signal is correlated with the 4.8 hour orbital period, and the muon content of the showers in the signal is inconsistent with the conventional prediction of gamma- initiated showers. An episodic signal is also reported for Hercules X-1, and it consists of two bursts of less than one hour duration on 24 July 1986. The probability is one chance in 12,000 that this observation is not associated with Hercules X-1. The signal is pulsed at frequency near, but significantly different from, the x-ray pulsar frequency. The muon content of the signal showers is also anomalous, assuming the showers are initiated by gamma rays. 62 refs., 60 figs.
- Research Organization:
- Los Alamos National Lab., NM (USA)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 6862675
- Report Number(s):
- LA-11431-T; ON: DE89004543
- Resource Relation:
- Other Information: Thesis (Ph.D.). Paper copy only, copy does not permit microfiche production
- Country of Publication:
- United States
- Language:
- English
Similar Records
A study of ultra high energy radiation associated with Hercules X-1
Ultra-high energy signals from Hercules X-1
Related Subjects
GENERAL PHYSICS
COSMIC GAMMA SOURCES
MUON DETECTION
GAMMA DETECTION
COSMIC GAMMA BURSTS
EQUATIONS
GAMMA ASTRONOMY
NUMERICAL DATA
PULSARS
SHOWER COUNTERS
ASTRONOMY
CHARGED PARTICLE DETECTION
COSMIC RADIATION
COSMIC RADIO SOURCES
COSMIC RAY SOURCES
DATA
DETECTION
INFORMATION
IONIZING RADIATIONS
MEASURING INSTRUMENTS
PRIMARY COSMIC RADIATION
RADIATION DETECTION
RADIATION DETECTORS
RADIATIONS
640101* - Astrophysics & Cosmology- Cosmic Radiation