An Optical Survey of the Position Error Contours of Unidentified High-Energy Gamma-Ray Sources at Galactic Latitude |<i>b</i>| &gt; 20°

Bloom, S. D.; Dale, Daniel A.; Cool, R. J.; Dupczak, K.; Miller, C. J.; Haugsjaa, A.; Peters, Charee; Tornikoski, M.; Wallace, Paul; Pierce, Michael

doi:10.1086/421375

Cited by 5 publications

(1 citation statement)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(5) V -band interstellar absorption referred from Schlegel et al (1998). ( 6 (1977); 17 Hauser et al (2010); 18 Sandage (1972); 19 Tramacere, Rea (2009); 20 Webb et al (1990); 21 Kikuchi (1988); 22 Gaskell (1982); 23 Impey, Tapia (1988); 24 Barbieri et al (1983); 25 Kataoka et al (2008); 26 Fan, Lin (2000a); 27 Sillanpaa et al (1985); 28 Takalo et al (1990); 29 Soldi et al (2008); 30 Raiteri et al (2008a); 31 Takalo et al (1998); 32 Zekl et al (1981); 33 Yoshida et al (2008); 34 Wills et al (1992); 35 Morton et al (2008); 36 Villata et al (2006b); 37 Corso et al (1988); 38 Tapia et al (1977); 39 Xie et al (2002); 40 Fan et al (1998); 41 Raiteri et al (1999); 42 Nesci et al (2002);43 Miller (1978); 44 Smith et al (1987); 45 Pica et al (1988);46 Liu et al (1995); 47 Qian et al (2002); 48 Bloom et al (2004); 49 Carini et al (1998); 50 Massaro et al (1996); 51 Brissenden et al (1990); 52 Griffiths et al (1989); 53 Fan, Lin (2000b); 54 Kapanadze (2009); 55 Liu et al (1997); 56 Villata et al (2000); 57…”

Section: Samplementioning

confidence: 99%

Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization

Ikejiri¹,

Uemura²,

Sasada³

et al. 2011

Publications of the Astronomical Society of Japan

166

153

View full text Add to dashboard Cite

We report on the correlation between the flux, color and polarization variations on time scales of daysmonths in blazars, and discuss their universal aspects. We performed monitoring of 42 blazars in the optical and near-infrared bands from 2008 to 2010 using TRISPEC attached to the "Kanata" 1.5-m telescope. We found that 28 blazars exhibited "bluer-when-brighter" trends in their whole or a part of time-series data sets. This corresponds to 88% of objects that were observed for > 10 days. Thus, our observation unambiguously confirmed that the "bluer-when-brighter" trend is common in the emission from blazar jets. This trend was apparently generated by a variation component with a constant and relatively blue color and an underlying red component. Prominent short-term flares on time scales of days-weeks tended to exhibit a spectral hysteresis; their rising phases were bluer than their decay phases around the flare maxima. In contrast to the strong flux-color correlation, the correlation of the flux and polarization degree was relatively weak; only 10 objects showed significant positive correlations. Rotations of polarization were detected only in three objects: PKS 1510−089, 3C 454.3, and PKS 1749+096, and possibly in S5 0716+714. We also investigated the dependence of the degree of variability on the luminosity and the synchrotron peak frequency, ν peak . As a result, we found that lower luminosity and higher ν peak objects had smaller variations in their amplitudes both in the flux, color, and polarization degree. Our observation suggests the presence of several distinct emitting sources, which have different variation time-scales, colors, and polarizations. We propose that the energy injection by, for example, internal shocks in relativistic shells is a major factor for blazar variations on time scales of both days and months.

show abstract

Section: Samplementioning

confidence: 99%

Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization

Ikejiri¹,

Uemura²,

Sasada³

et al. 2011

Publications of the Astronomical Society of Japan

166

153

View full text Add to dashboard Cite

show abstract

A Multiwavelength Investigation of Unidentified EGRET Sources

Wallace

Bloom

Lewis

Multiwavelength Approach to Unidentified Gamma-Ray Sources

View full text Add to dashboard Cite

A Multiwavelength Investigation of Unidentified Egret Sources

Wallace

Bloom

Lewis

2005

Astrophys Space Sci

Self Cite

View full text Add to dashboard Cite

Statistical studies indicate that the 271 point sources of high-energy gamma rays belong to two groups: a galactic population and an isotropic extragalactic population. Many unidentified extragalactic sources are certainly blazars, and it is the intention of this work to uncover gamma-ray blazars missed by previous attempts. Until recently, searches for blazar counterparts to unidentified EGRET sources have focused on finding AGN that have 5-GHz radio flux densities S 5 near or above 1 Jy. However, the recent blazar identification of 3EG J2006-2321 (S 5 = 260 mJy) and other work suggest that careful studies of weaker flat-spectrum sources may be fruitful. In this spirit, error circles of four high-latitude unidentified EGRET sources have been searched for 5-GHz sources. The gammaray sources are 3EG J1133+0033, 3EG J1212+2304, 3EG J1222+2315, and 3EG J1227+4302. Within the error contours of each of the four sources are found six radio candidates; by observing the positions of the radio sources with the 0.81-m Tenagra II telescope it is determined that 14 of these 24 radio sources have optical counterparts with R < 22. Eight of these from two different EGRET sources have been observed in the B, V , and R bands in more than one epoch and the analysis of these data is ongoing. Any sources that are found to be variable will be the objects of multi-epoch polarimetry studies.

show abstract

An Optical Survey of the Position Error Contours of Unidentified High-Energy Gamma-Ray Sources at Galactic Latitude |b| > 20°

Cited by 5 publications

References 20 publications

Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization

Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization

A Multiwavelength Investigation of Unidentified EGRET Sources

A Multiwavelength Investigation of Unidentified Egret Sources

Contact Info

Product

Resources

About