MULTIWAVELENGTH OBSERVATIONS OF LS I +61{sup 0} 303 WITH VERITAS, SWIFT, AND RXTE

Journal Article · Sat Aug 01 04:00:00 EDT 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/700/2/1034; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21313816

Acciari, V A ^[1]; Aliu, E ^[2]; Arlen, T; Chow, Y C ^[3]; Bautista, M; Cogan, P ^[4]; Beilicke, M; Bugaev, V ^[5]; Benbow, W ^[6]; Boettcher, M ^[7]; Bradbury, S M; Daniel, M ^[8]; Butt, Y; Butt, Y ^[9]; Byrum, K ^[10]; Cannon, A ^[11]; Cesarini, A ^[12]; Ciupik, L ^[13]; Colin, P ^[14]

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1. Department of Life and Physical Sciences, Galway-Mayo Institute of Technology, Dublin Road, Galway (Ireland)
2. Department of Physics and Astronomy and the Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)
3. Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)
4. Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada)
5. Department of Physics, Washington University, St. Louis, MO 63130 (United States)
6. Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States)
7. Astrophysical Institute, Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States)
8. School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom)
9. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
10. Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)
11. School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)
12. School of Physics, National University of Ireland, Galway (Ireland)
13. Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States)
14. Physics Department, University of Utah, Salt Lake City, UT 84112 (United States)

We present results from a long-term monitoring campaign on the TeV binary LSI +61{sup 0} 303 with VERITAS at energies above 500 GeV, and in the 2-10 keV hard X-ray bands with RXTE and Swift, sampling nine 26.5 day orbital cycles between 2006 September and 2008 February. The binary was observed by VERITAS to be variable, with all integrated observations resulting in a detection at the 8.8{sigma} (2006/2007) and 7.3{sigma} (2007/2008) significance level for emission above 500 GeV. The source was detected during active periods with flux values ranging from 5% to 20% of the Crab Nebula, varying over the course of a single orbital cycle. Additionally, the observations conducted in the 2007-2008 observing season show marginal evidence (at the 3.6{sigma} significance level) for TeV emission outside the apastron passage of the compact object around the Be star. Contemporaneous hard X-ray observations with RXTE and Swift show large variability with flux values typically varying between 0.5 and 3.0 x10{sup -11} erg cm{sup -2} s{sup -1} over a single orbital cycle. The contemporaneous X-ray and TeV data are examined and it is shown that the TeV sampling is not dense enough to detect a correlation between the two bands.

• OSTI ID: 21313816
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 700; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS
CRAB NEBULA
EMISSION
GAMMA RADIATION
GEV RANGE 100-1000
HARD X RADIATION
STARS
TEV RANGE